NCBI Conserved Domain Search

Immunoglobulin (Ig)-like domain of human neurofascin (NF); member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the first immunoglobulin (Ig)-like domain of human neurofascin (NF). NF belongs to the L1 subfamily of cell adhesion molecules (CAMs) and is comprised of an extracellular region having six Ig-like domains and five fibronectin type III domains, a transmembrane region, and a cytoplasmic domain. NF has many alternatively spliced isoforms having different temporal expression patterns during development. NF participates in axon subcellular targeting and synapse formation, however little is known of the functions of the different isoforms. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lacks a C" strand.

Pssm-ID: 409459 Cd Length: 95 Bit Score: 211.76 E-value: 4.56e-64

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369   35 PTITKQSAKDHIVDPRDNILIECEAKGNPAPSFHWTRNSRFFNIAKDPRVSMRRRSGTLVIDFRSGGRPEEYEGEYQCFA 114
Cdd:cd05875      1 PTITKQSAKDYIVDPRDNILIECEAKGNPVPTFHWTRNGKFFNVAKDPRVSMRRRSGTLVIDFRGGGRPEDYEGEYQCFA 80

                           90
                   ....*....|....*
gi 2217265369  115 RNKFGTALSNRIRLQ 129
Cdd:cd05875     81 RNKFGTALSNKIRLQ 95

Immunoglobulin (Ig)-like domain of the L1 cell adhesion molecule (CAM) and similar proteins; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the first immunoglobulin (Ig)-like domain of the L1 cell adhesion molecule (CAM). L1 belongs to the L1 subfamily of cell adhesion molecules (CAMs) and is comprised of an extracellular region having six Ig-like domains and five fibronectin type III domains, a transmembrane region and an intracellular domain. L1 is primarily expressed in the nervous system and is involved in its development and function. L1 is associated with an X-linked recessive disorder, X-linked hydrocephalus, MASA syndrome, or spastic paraplegia type 1, that involves abnormalities of axonal growth. This group also contains NrCAM [Ng(neuronglia)CAM-related cell adhesion molecule], which is primarily expressed in the nervous system, and human neurofascin. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lacks a C" strand.

Pssm-ID: 409396 [Multi-domain] Cd Length: 94 Bit Score: 184.15 E-value: 2.48e-54

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369   35 PTITKQSAKDHIVDPRDNILIECEAKGNPAPSFHWTRNSRFFNIAKDPRVSMRRRSGTLVIDFRSGGrPEEYEGEYQCFA 114
Cdd:cd05733      1 PTITEQSPKDYIVDPRDNITIKCEAKGNPQPTFRWTKDGKFFDPAKDPRVSMRRRSGTLVIDNHNGG-PEDYQGEYQCYA 79

                           90
                   ....*....|....*
gi 2217265369  115 RNKFGTALSNRIRLQ 129
Cdd:cd05733     80 SNELGTAISNEIRLV 94

Second immunoglobulin (Ig)-like domain of the L1 cell adhesion molecule (CAM), and similar domains; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the second immunoglobulin (Ig)-like domain of the L1 cell adhesion molecule (CAM) and similar proteins. L1 belongs to the L1 subfamily of cell adhesion molecules (CAMs) and is comprised of an extracellular region having six Ig-like domains, five fibronectin type III domains, a transmembrane region, and an intracellular domain. L1 is primarily expressed in the nervous system and is involved in its development and function. L1 is associated with an X-linked recessive disorder, X-linked hydrocephalus, MASA syndrome, or spastic paraplegia type 1 that involves abnormalities of axonal growth. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409432 Cd Length: 91 Bit Score: 178.07 E-value: 3.09e-52

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  138 KENLDPVVVQEGAPLTLQCNPPPGLPSPVIFWMSSSMEPITQDKRVSQGHNGDLYFSNVMLQDMQTDYSCNARFHFTHTI 217
Cdd:cd05845      1 KEKIDPVEVEEGDPVVLPCNPPKGAPPPRIYWMNSSLEHITQDERVSMGQNGDLYFSNVMEQDSHPDYICHAHFPGTRTI 80

                           90
                   ....*....|.
gi 2217265369  218 QQKNPFTLKVL 228
Cdd:cd05845     81 VQKEPITLKVL 91

Third immunoglobulin (Ig)-like domain of the L1 cell adhesion molecule (CAM), and similar domains; The members here are composed of the third immunoglobulin (Ig)-like domain of the L1 cell adhesion molecule (CAM). L1 belongs to the L1 subfamily of cell adhesion molecules (CAMs) and is comprised of an extracellular region having six Ig-like domains and five fibronectin type III domains, a transmembrane region and an intracellular domain. L1 is primarily expressed in the nervous system and is involved in its development and function. L1 is associated with an X-linked recessive disorder, X-linked hydrocephalus, MASA syndrome, and spastic paraplegia type 1, that involves abnormalities of axonal growth. This group also contains the chicken neuron-glia cell adhesion molecule, Ng-CAM and human neurofascin.

Pssm-ID: 409394 [Multi-domain] Cd Length: 83 Bit Score: 167.59 E-value: 8.83e-49

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  246 TASSQMVLRGMDLLLECIASGVPTPDIAWYKKGGDLPSDKAKFENFNKALRITNVSEEDSGEYFCLASNKMGSIRHTISV 325
Cdd:cd05731      1 SESSTMVLRGGVLLLECIAEGLPTPDIRWIKLGGELPKGRTKFENFNKTLKIENVSEADSGEYQCTASNTMGSARHTISV 80


                   ...
gi 2217265369  326 RVK 328
Cdd:cd05731     81 TVE 83

Fourth immunoglobulin (Ig)-like domain of NrCAM (NgCAM-related cell adhesion molecule); The members here are composed of the fourth immunoglobulin (Ig)-like domain of NrCAM (NgCAM-related cell adhesion molecule). NrCAM belongs to the L1 subfamily of cell adhesion molecules (CAMs) and is comprised of an extracellular region having six IG-like domains and five fibronectin type III domains, a transmembrane region, and an intracellular domain. NrCAM is primarily expressed in the nervous system.

Pssm-ID: 409454 Cd Length: 89 Bit Score: 148.98 E-value: 4.06e-42

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  332 YWLDEPKNLILAPGEDGRLVCRANGNPKPTVQWMVNGEPLQSAPPNPNREVAGDTIIFRDTQISSRAVYQCNTSNEHGYL 411
Cdd:cd05868      1 YWITAPTNLVLSPGEDGTLICRANGNPKPSISWLTNGVPIEIAPTDPSRKVDGDTIIFSKVQERSSAVYQCNASNEYGYL 80


                   ....*....
gi 2217265369  412 LANAFVSVL 420
Cdd:cd05868     81 LANAFVNVL 89

Immunoglobulin (Ig)-like domain of NrCAM (Ng (neuronglia) CAM-related cell adhesion molecule); member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the first immunoglobulin (Ig)-like domain of NrCAM (Ng (neuronglia) CAM-related cell adhesion molecule). NrCAM belongs to the L1 subfamily of cell adhesion molecules (CAMs) and is comprised of an extracellular region having six Ig-like domains and five fibronectin type III domains, a transmembrane region, and an intracellular domain. NrCAM is primarily expressed in the nervous system.

Pssm-ID: 409458 Cd Length: 95 Bit Score: 142.82 E-value: 7.02e-40

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369   35 PTITKQSAKDHIVDPRDNILIECEAKGNPAPSFHWTRNSRFFNIAKDPRVSMRRRSGTLVIDFRSGGRPEEYEGEYQCFA 114
Cdd:cd05874      1 PTITHQSPKDYIVDPRENIVIQCEAKGKPPPSFSWTRNGTHFDIDKDPKVTMKPNTGTLVINIMNGEKAEAYEGVYQCTA 80

                           90
                   ....*....|..
gi 2217265369  115 RNKFGTALSNRI 126
Cdd:cd05874     81 RNERGAAVSNNI 92

Fourth immunoglobulin (Ig)-like domain of L1, Ng-CAM (Neuron-glia CAM cell adhesion molecule), and NrCAM (Ng-CAM-related); The members here are composed of the fourth immunoglobulin (Ig)-like domain of L1, Ng-CAM (Neuron-glia CAM cell adhesion molecule), and NrCAM (Ng-CAM-related). These proteins belong to the L1 subfamily of cell adhesion molecules (CAMs) and are comprised of an extracellular region having six Ig-like domains and five fibronectin type III domains, a transmembrane region and an intracellular domain. These molecules are primarily expressed in the nervous system. L1 is associated with an X-linked recessive disorder, X-linked hydrocephalus, MASA syndrome, or spastic paraplegia type 1, that involves abnormalities of axonal growth.

Pssm-ID: 409367 [Multi-domain] Cd Length: 89 Bit Score: 135.27 E-value: 2.68e-37

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  332 YWLDEPKNLILAPGEDGRLVCRANGNPKPTVQWMVNGEPLQSAPPNPNREVAGDTIIFRDTQISSRAVYQCNTSNEHGYL 411
Cdd:cd04978      1 YWIIEPPSLVLSPGETGELICEAEGNPQPTITWRLNGVPIEPAPEDMRRTVDGRTLIFSNLQPNDTAVYQCNASNVHGYL 80


                   ....*....
gi 2217265369  412 LANAFVSVL 420
Cdd:cd04978     81 LANAFLHVL 89

Bravo-like intracellular region; This is the very C-terminal intracellular region of neural adhesion molecule L1 proteins that are also known as Bravo or NrCAM. It lies upstream of the IG and Fn3 domains and has the highly conserved motif FIGEY. The function is not known.

Pssm-ID: 464016 Cd Length: 88 Bit Score: 131.67 E-value: 4.19e-36

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369 1233 KRSRGGKYPVREKKDVPLGPEDPKEEDGSF-DYSDEDNKPLQGSQTSLDGTIKQQESD--DSLVDYGEGGEGQFNEDGSF 1309
Cdd:pfam13882    1 KRNKGGKYSVKEKEDAHGDPEDQPMDEDAFgEYSDLDEKPLKSSQPSLSSDSKLVDSDstDSLDDYGDGDGGQFNEDGSF 80


                   ....*...
gi 2217265369 1310 IGQYTVKK 1317
Cdd:pfam13882   81 IGQYGGKK 88

Third immunoglobulin (Ig)-like domain of the L1 cell adhesion molecule (CAM); The members here are composed of the third immunoglobulin (Ig)-like domain of the L1 cell adhesion molecule (CAM). L1 belongs to the L1 subfamily of cell adhesion molecules (CAMs) and is comprised of an extracellular region having six Ig-like domains, five fibronectin type III domains, a transmembrane region and an intracellular domain. L1 is primarily expressed in the nervous system and is involved in its development and function. L1 is associated with an X-linked recessive disorder, X-linked hydrocephalus, MASA syndrome, or spastic paraplegia type 1, that involves abnormalities of axonal growth. This group also contains the chicken neuron-glia cell adhesion molecule, Ng-CAM.

Pssm-ID: 409460 [Multi-domain] Cd Length: 83 Bit Score: 100.37 E-value: 3.68e-25

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  248 SSQMVLRGMDLLLECIASGVPTPDIAWYKKGGDLPSDKAKFENFNKALRITNVSEEDSGEYFCLASNKMGSIRHTISVRV 327
Cdd:cd05876      3 SSLVALRGQSLVLECIAEGLPTPTVKWLRPSGPLPPDRVKYQNHNKTLQLLNVGESDDGEYVCLAENSLGSARHAYYVTV 82


                   .
gi 2217265369  328 K 328
Cdd:cd05876     83 E 83

Fourth immunoglobulin (Ig)-like domain of the L1 cell adhesion molecule (CAM); The members here are composed of the fourth immunoglobulin (Ig)-like domain of the L1 cell adhesion molecule (CAM). L1 is comprised of an extracellular region having six Ig-like domains and five fibronectin type III domains, a transmembrane region, and an intracellular domain. L1 is primarily expressed in the nervous system and is involved in its development and function. L1 is associated with an X-linked recessive disorder, X-linked hydrocephalus, MASA syndrome, and spastic paraplegia type 1, that involves abnormalities of axonal growth. This group also contains the chicken neuron-glia cell adhesion molecule, Ng-CAM.

Pssm-ID: 409453 [Multi-domain] Cd Length: 89 Bit Score: 99.20 E-value: 1.24e-24

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  332 YWLDEPKNLILAPGEDGRLVCRANGNPKPTVQWMVNGEPLQSAPPNPNREVAGDTIIFRDTQISSRAVYQCNTSNEHGYL 411
Cdd:cd05867      1 YWTRRPQSHLYGPGETARLDCQVEGIPTPNITWSINGAPIEGTDPDPRRHVSSGALILTDVQPSDTAVYQCEARNRHGNL 80


                   ....*....
gi 2217265369  412 LANAFVSVL 420
Cdd:cd05867     81 LANAHVHVV 89

Fibronectin type 3 domain; One of three types of internal repeats found in the plasma protein fibronectin. Its tenth fibronectin type III repeat contains an RGD cell recognition sequence in a flexible loop between 2 strands. Approximately 2% of all animal proteins contain the FN3 repeat; including extracellular and intracellular proteins, membrane spanning cytokine receptors, growth hormone receptors, tyrosine phosphatase receptors, and adhesion molecules. FN3-like domains are also found in bacterial glycosyl hydrolases.

Pssm-ID: 238020 [Multi-domain] Cd Length: 93 Bit Score: 78.31 E-value: 2.81e-17

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  622 PDRPRDLELTDLAERSVRLTWIPGDANNSPITDYVVQFEEDqfQPGVWHDHSKYPGSVNSAVLR-LSPYVNYQFRVIAIN 700
Cdd:cd00063      1 PSPPTNLRVTDVTSTSVTLSWTPPEDDGGPITGYVVEYREK--GSGDWKEVEVTPGSETSYTLTgLKPGTEYEFRVRAVN 78

                           90
                   ....*....|..
gi 2217265369  701 EVGSSHPSLPSE 712
Cdd:cd00063     79 GGGESPPSESVT 90

Immunoglobulin like; IG domains that cannot be classified into one of IGv1, IGc1, IGc2, IG.

Pssm-ID: 214653 [Multi-domain] Cd Length: 85 Bit Score: 77.16 E-value: 4.88e-17

                            10        20        30        40        50        60        70        80
                    ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369   248 SSQMVLRGMDLLLECIASGVPTPDIAWYKKGGDLPSDKAKF----ENFNKALRITNVSEEDSGEYFCLASNKMGSIRHTI 323
Cdd:smart00410    2 PSVTVKEGESVTLSCEASGSPPPEVTWYKQGGKLLAESGRFsvsrSGSTSTLTISNVTPEDSGTYTCAATNSSGSASSGT 81


                    ....
gi 2217265369   324 SVRV 327
Cdd:smart00410   82 TLTV 85

Fourth Ig domain of the neural cell adhesion molecule contactin-2, and similar domains; The members here are composed of the fourth Ig domain of the neural cell adhesion molecule contactin-2. Contactins are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. Contactin-2 (also called TAG-1, axonin-1) facilitates cell adhesion by homophilic binding between molecules in apposed membranes. The first four Ig domains form the intermolecular binding fragment which arranges as a compact U-shaped module by contacts between Ig domains 1 and 4, and domains 2 and 3. It has been proposed that a linear zipper-like array forms, from contactin-2 molecules alternatively provided by the two apposed membranes.

Pssm-ID: 143205 [Multi-domain] Cd Length: 85 Bit Score: 73.79 E-value: 7.70e-16

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  333 WLDEPKNLILAPGEDGRLVCRANGNPKPTVQWMVNGEPLqsapPNPNR-EVAGDTIIFRDTQISSRAVYQCNTSNEHGYL 411
Cdd:cd05728      2 WLKVISDTEADIGSSLRWECKASGNPRPAYRWLKNGQPL----ASENRiEVEAGDLRITKLSLSDSGMYQCVAENKHGTI 77


                   ....*...
gi 2217265369  412 LANAFVSV 419
Cdd:cd05728     78 YASAELAV 85

Fifth Ig-like domain of Roundabout (Robo) homolog 1/2, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the fifth Ig-like domain of Roundabout (Robo) homolog 1/2 and similar domains. Robo receptors play a role in the development of the central nervous system (CNS), and are receptors of Slit protein. Slit is a repellant secreted by the neural cells in the midline. Slit acts through Robo to prevent most neurons from crossing the midline from either side. Three mammalian Robo homologs (Robo1, -2, and -3), and three mammalian Slit homologs (Slit-1,-2, -3), have been identified. Commissural axons, which cross the midline, express low levels of Robo; longitudinal axons, which avoid the midline, express high levels of Robo. Robo1, -2, and -3 are expressed by commissural neurons in the vertebrate spinal cord and Slits 1, -2, -3 are expressed at the ventral midline. Robo-3 is a divergent member of the Robo family which instead of being a positive regulator of slit responsiveness, antagonizes slit responsiveness in precrossing axons. The Slit-Robo interaction is mediated by the second leucine-rich repeat (LRR) domain of Slit and the two N-terminal Ig domains of Robo, Ig1 and Ig2. The primary Robo binding site for Slit2 has been shown by surface plasmon resonance experiments and mutational analysis to be is the Ig1 domain, while the Ig2 domain has been proposed to harbor a weak secondary binding site. The fifth Ig-like domain of Robo 1 and 2 is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors

Pssm-ID: 409544 [Multi-domain] Cd Length: 87 Bit Score: 72.53 E-value: 2.56e-15

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|.
gi 2217265369  444 LDCPFFGSPIPTLRWFKngQGSNLDGGNYHVY--ENGSLEIKMIRKEDQGIYTCVATNILGKAENQVRLEV 512
Cdd:cd20952     19 LNCQATGEPVPTISWLK--DGVPLLGKDERITtlENGSLQIKGAEKSDTGEYTCVALNLSGEATWSAVLDV 87

Immunoglobulin I-set domain;

Pssm-ID: 400151 [Multi-domain] Cd Length: 90 Bit Score: 72.29 E-value: 2.63e-15

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  522 PEDQVARRGTTVQLECRVKHDPslKLTVSWLKDDEPLYIGNR--MKKEDD--SLTIFGVAERDQGSYTCVASTELDQDLA 597
Cdd:pfam07679    7 PKDVEVQEGESARFTCTVTGTP--DPEVSWFKDGQPLRSSDRfkVTYEGGtyTLTISNVQPDDSGKYTCVATNSAGEAEA 84


                   ....*.
gi 2217265369  598 KAYLTV 603
Cdd:pfam07679   85 SAELTV 90

Immunoglobulin I-set domain;

Pssm-ID: 400151 [Multi-domain] Cd Length: 90 Bit Score: 70.36 E-value: 1.43e-14

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 2217265369  255 GMDLLLECIASGVPTPDIAWYKKGGDLPSD---KAKFENFNKALRITNVSEEDSGEYFCLASNKMGSIRHTISVRV 327
Cdd:pfam07679   15 GESARFTCTVTGTPDPEVSWFKDGQPLRSSdrfKVTYEGGTYTLTISNVQPDDSGKYTCVATNSAGEAEASAELTV 90

Immunoglobulin domain; This family contains immunoglobulin-like domains.

Pssm-ID: 464046 [Multi-domain] Cd Length: 78 Bit Score: 69.52 E-value: 1.96e-14

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  248 SSQMVLRGMDLLLECIASGVPTPDIAWYKKGG---DLPSDKAKFENFNKALRITNVSEEDSGEYFCLASN 314
Cdd:pfam13927    9 SSVTVREGETVTLTCEATGSPPPTITWYKNGEpisSGSTRSRSLSGSNSTLTISNVTRSDAGTYTCVASN 78

Fibronectin type III domain;

Pssm-ID: 394996 [Multi-domain] Cd Length: 85 Bit Score: 67.83 E-value: 8.71e-14

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  623 DRPRDLELTDLAERSVRLTWIPGDANNSPITDYVVQFEEDQfQPGVWHdHSKYPGSVNSAVLR-LSPYVNYQFRVIAINE 701
Cdd:pfam00041    1 SAPSNLTVTDVTSTSLTVSWTPPPDGNGPITGYEVEYRPKN-SGEPWN-EITVPGTTTSVTLTgLKPGTEYEVRVQAVNG 78


                   ....*..
gi 2217265369  702 VGSSHPS 708
Cdd:pfam00041   79 GGEGPPS 85

Fourth immunoglobulin (Ig)-like domain of hemolin, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the fourth immunoglobulin (Ig)-like domain of hemolin and similar proteins. Hemolin, an insect immunoglobulin superfamily (IgSF) member containing four Ig-like domains, is a lipopolysaccharide-binding immune protein induced during bacterial infection. Hemolin shares significant sequence similarity with the first four Ig-like domains of the transmembrane cell adhesion molecules (CAMs) of the L1 family. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. The fourth Ig-like domain of hemolin is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set domains, members of the I-set have a discontinuous A strand but lack a C" strand. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409570 [Multi-domain] Cd Length: 88 Bit Score: 65.11 E-value: 9.06e-13

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  331 PYWLDEP-KNLILAPGEDGRLVCRANGNPKPTVQWMVNGEPLQSAPPNPNREVAGDTIIfrDTQISSRAVYQCNTSNEHG 409
Cdd:cd20978      1 PKFIQKPeKNVVVKGGQDVTLPCQVTGVPQPKITWLHNGKPLQGPMERATVEDGTLTII--NVQPEDTGYYGCVATNEIG 78

                           90
                   ....*....|
gi 2217265369  410 YLLANAFVSV 419
Cdd:cd20978     79 DIYTETLLHV 88

Immunoglobulin domain; The members here are composed of the immunoglobulin (Ig) domain found in the Ig superfamily. The Ig superfamily is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. Members of this group are components of immunoglobulin, neuroglia, cell surface glycoproteins, including T-cell receptors, CD2, CD4, CD8, and membrane glycoproteins, including butyrophilin and chondroitin sulfate proteoglycan core protein. A predominant feature of most Ig domains is a disulfide bridge connecting the two beta-sheets with a tryptophan residue packed against the disulfide bond. Ig superfamily (IgSF) domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Typically, the V-set domains have A, B, E, and D strands in one sheet and A', G, F, C, C' and C" in the other. The structures in C1-set are smaller than those in the V-set; they have one beta sheet that is formed by strands A, B, E, and D and the other by strands G, F, C, and C'. Moreover, a C1-set Ig domain contains a short C' strand (three residues) and lacks A' and C" strand. Unlike other Ig domain sets, C2-set structures do not have a D strand. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409353 [Multi-domain] Cd Length: 70 Bit Score: 64.66 E-value: 9.98e-13

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 2217265369  258 LLLECIASGVPTPDIAWYKKGGDLPSDKA---KFENFNKALRITNVSEEDSGEYFCLASNKMGSIRHTI 323
Cdd:cd00096      1 VTLTCSASGNPPPTITWYKNGKPLPPSSRdsrRSELGNGTLTISNVTLEDSGTYTCVASNSAGGSASAS 69

Third immunoglobulin (Ig)-like domain in Robo (roundabout) receptors; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the third immunoglobulin (Ig)-like domain in Robo (roundabout) receptors. Robo receptors play a role in the development of the central nervous system (CNS), and are receptors of Slit protein. Slit is a repellant secreted by the neural cells in the midline. Slit acts through Robo to prevent most neurons from crossing the midline from either side. Three mammalian Robo homologs (Robo1, Robo2, Robo3), and three mammalian Slit homologs (Slit-1,Slit-2, Slit-3), have been identified. Commissural axons, which cross the midline, express low levels of Robo; longitudinal axons, which avoid the midline, express high levels of Robo. Robo1, Robo2, and Robo3 are expressed by commissural neurons in the vertebrate spinal cord and Slit-1, Slit-2, and Slit-3 are expressed at the ventral midline. Robo-3 is a divergent member of the Robo family which instead of being a positive regulator of Slit responsiveness, antagonizes Slit responsiveness in precrossing axons. The Slit-Robo interaction is mediated by the second leucine-rich repeat (LRR) domain of Slit and the two N-terminal Ig domains of Robo, Ig1 and Ig2. The primary Robo binding site for Slit2 has been shown by surface plasmon resonance experiments and mutational analysis to be the Ig1 domain, while the Ig2 domain has been proposed to harbor a weak secondary binding site. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409390 [Multi-domain] Cd Length: 83 Bit Score: 64.34 E-value: 1.59e-12

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  429 PRNQlirVILYNRT-RLDCPFFGSPIPTLRWFKNGqgSNLDGGNYHVYENGSLEIKMIRKEDQGIYTCVATNILGKAENQ 507
Cdd:cd05725      4 PQNQ---VVLVDDSaEFQCEVGGDPVPTVRWRKED--GELPKGRYEILDDHSLKIRKVTAGDMGSYTCVAENMVGKIEAS 78


                   ....*
gi 2217265369  508 VRLEV 512
Cdd:cd05725     79 ATLTV 83

Immunoglobulin I-set domain;

Pssm-ID: 400151 [Multi-domain] Cd Length: 90 Bit Score: 64.59 E-value: 1.61e-12

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 2217265369  443 RLDCPFFGSPIPTLRWFKNGQGSNlDGGNYHVYENG---SLEIKMIRKEDQGIYTCVATNILGKAENQVRLEV 512
Cdd:pfam07679   19 RFTCTVTGTPDPEVSWFKDGQPLR-SSDRFKVTYEGgtyTLTISNVQPDDSGKYTCVATNSAGEAEASAELTV 90

Immunoglobulin like; IG domains that cannot be classified into one of IGv1, IGc1, IGc2, IG.

Pssm-ID: 214653 [Multi-domain] Cd Length: 85 Bit Score: 64.06 E-value: 1.97e-12

                            10        20        30        40        50        60        70
                    ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 2217265369   443 RLDCPFFGSPIPTLRWFKNGQGSNLDGGNYHVYENG---SLEIKMIRKEDQGIYTCVATNILGKAENQVRLEV 512
Cdd:smart00410   13 TLSCEASGSPPPEVTWYKQGGKLLAESGRFSVSRSGstsTLTISNVTPEDSGTYTCAATNSSGSASSGTTLTV 85

Immunoglobulin domain; The members here are composed of the immunoglobulin (Ig) domain found in the Ig superfamily. The Ig superfamily is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. Members of this group are components of immunoglobulin, neuroglia, cell surface glycoproteins, including T-cell receptors, CD2, CD4, CD8, and membrane glycoproteins, including butyrophilin and chondroitin sulfate proteoglycan core protein. A predominant feature of most Ig domains is a disulfide bridge connecting the two beta-sheets with a tryptophan residue packed against the disulfide bond. Ig superfamily (IgSF) domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Typically, the V-set domains have A, B, E, and D strands in one sheet and A', G, F, C, C' and C" in the other. The structures in C1-set are smaller than those in the V-set; they have one beta sheet that is formed by strands A, B, E, and D and the other by strands G, F, C, and C'. Moreover, a C1-set Ig domain contains a short C' strand (three residues) and lacks A' and C" strand. Unlike other Ig domain sets, C2-set structures do not have a D strand. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409353 [Multi-domain] Cd Length: 70 Bit Score: 63.12 E-value: 3.32e-12

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 2217265369  443 RLDCPFFGSPIPTLRWFKNGQG--SNLDGGNYHVYENGSLEIKMIRKEDQGIYTCVATNILGKAEN 506
Cdd:cd00096      2 TLTCSASGNPPPTITWYKNGKPlpPSSRDSRRSELGNGTLTISNVTLEDSGTYTCVASNSAGGSAS 67

Third immunoglobulin (Ig)-like domain in Robo (roundabout) receptors; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the third immunoglobulin (Ig)-like domain in Robo (roundabout) receptors. Robo receptors play a role in the development of the central nervous system (CNS), and are receptors of Slit protein. Slit is a repellant secreted by the neural cells in the midline. Slit acts through Robo to prevent most neurons from crossing the midline from either side. Three mammalian Robo homologs (Robo1, Robo2, Robo3), and three mammalian Slit homologs (Slit-1,Slit-2, Slit-3), have been identified. Commissural axons, which cross the midline, express low levels of Robo; longitudinal axons, which avoid the midline, express high levels of Robo. Robo1, Robo2, and Robo3 are expressed by commissural neurons in the vertebrate spinal cord and Slit-1, Slit-2, and Slit-3 are expressed at the ventral midline. Robo-3 is a divergent member of the Robo family which instead of being a positive regulator of Slit responsiveness, antagonizes Slit responsiveness in precrossing axons. The Slit-Robo interaction is mediated by the second leucine-rich repeat (LRR) domain of Slit and the two N-terminal Ig domains of Robo, Ig1 and Ig2. The primary Robo binding site for Slit2 has been shown by surface plasmon resonance experiments and mutational analysis to be the Ig1 domain, while the Ig2 domain has been proposed to harbor a weak secondary binding site. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409390 [Multi-domain] Cd Length: 83 Bit Score: 62.41 E-value: 6.60e-12

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  520 RMPEDQVARRGTTVQLECRVKHDPSLklTVSWLKDDEPLYIGNRMKKEDDSLTIFGVAERDQGSYTCVASTELDQDLAKA 599
Cdd:cd05725      2 KRPQNQVVLVDDSAEFQCEVGGDPVP--TVRWRKEDGELPKGRYEILDDHSLKIRKVTAGDMGSYTCVAENMVGKIEASA 79


                   ....
gi 2217265369  600 YLTV 603
Cdd:cd05725     80 TLTV 83

Sixth immunoglobulin (Ig) domain of contactin; The members here are composed of the sixth immunoglobulin (Ig) domain of contactins. Contactins are neural cell adhesion molecules and are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. The first four Ig domains form the intermolecular binding fragment, which arranges as a compact U-shaped module via contacts between Ig domains 1 and 4, and between Ig domains 2 and 3. Contactin-2 (TAG-1, axonin-1) may play a part in the neuronal processes of neurite outgrowth, axon guidance and fasciculation, and neuronal migration. This group also includes contactin-1 and contactin-5. The different contactins show different expression patterns in the central nervous system. During development and in adulthood, contactin-2 is transiently expressed in subsets of central and peripheral neurons. Contactin-5 is expressed specifically in the rat postnatal nervous system, peaking at about 3 weeks postnatal, and a lack of contactin-5 (NB-2) results in an impairment of neuronal activity in the rat auditory system. Contactin-5 is highly expressed in the adult human brain in the occipital lobe and in the amygdala. Contactin-1 is differentially expressed in tumor tissues and may, through a RhoA mechanism, facilitate invasion and metastasis of human lung adenocarcinoma.

Pssm-ID: 409359 Cd Length: 102 Bit Score: 62.95 E-value: 7.45e-12

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  514 DPTRIYRMPEDQVARRGTTVQLECRVKHDPSLKLTVSW--------LKDDEPLYIGNRMKKEDDSLTIFGVAERDQGSYT 585
Cdd:cd04970      1 DATRITLAPSNADITVGENATLQCHASHDPTLDLTFTWsfngvpidLEKIEGHYRRRYGKDSNGDLEIVNAQLKHAGRYT 80

                           90
                   ....*....|....*...
gi 2217265369  586 CVASTELDQDLAKAYLTV 603
Cdd:cd04970     81 CTAQTVVDSDSASATLVV 98

Third immunoglobulin (Ig)-like domain in Robo (roundabout) receptors; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the third immunoglobulin (Ig)-like domain in Robo (roundabout) receptors. Robo receptors play a role in the development of the central nervous system (CNS), and are receptors of Slit protein. Slit is a repellant secreted by the neural cells in the midline. Slit acts through Robo to prevent most neurons from crossing the midline from either side. Three mammalian Robo homologs (Robo1, Robo2, Robo3), and three mammalian Slit homologs (Slit-1,Slit-2, Slit-3), have been identified. Commissural axons, which cross the midline, express low levels of Robo; longitudinal axons, which avoid the midline, express high levels of Robo. Robo1, Robo2, and Robo3 are expressed by commissural neurons in the vertebrate spinal cord and Slit-1, Slit-2, and Slit-3 are expressed at the ventral midline. Robo-3 is a divergent member of the Robo family which instead of being a positive regulator of Slit responsiveness, antagonizes Slit responsiveness in precrossing axons. The Slit-Robo interaction is mediated by the second leucine-rich repeat (LRR) domain of Slit and the two N-terminal Ig domains of Robo, Ig1 and Ig2. The primary Robo binding site for Slit2 has been shown by surface plasmon resonance experiments and mutational analysis to be the Ig1 domain, while the Ig2 domain has been proposed to harbor a weak secondary binding site. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409390 [Multi-domain] Cd Length: 83 Bit Score: 62.03 E-value: 9.94e-12

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  248 SSQMVLRGMDLLLECIASGVPTPDIAWYKKGGDLPSDKAKFENfNKALRITNVSEEDSGEYFCLASNKMGSIRHTISVRV 327
Cdd:cd05725      5 QNQVVLVDDSAEFQCEVGGDPVPTVRWRKEDGELPKGRYEILD-DHSLKIRKVTAGDMGSYTCVAENMVGKIEASATLTV 83

Second immunoglobulin (Ig)-like domain in Robo (roundabout) receptors; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the second immunoglobulin (Ig)-like domain in Robo (roundabout) receptors. Robo receptors play a role in the development of the central nervous system (CNS), and are receptors of the Slit protein. Slit is a repellant secreted by the neural cells in the midline. Slit acts through Robo to prevent most neurons from crossing the midline from either side. Three mammalian Robo homologs (Robo1, Robo2, and Robo3), and three mammalian Slit homologs (Slit-1,Slit-2, Slit-3), have been identified. Commissural axons, which cross the midline, express low levels of Robo; longitudinal axons, which avoid the midline, express high levels of Robo. Robo1, Robo2, and Robo3 are expressed by commissural neurons in the vertebrate spinal cord and Slit-1, Slit-2, Slit-3 are expressed at the ventral midline. Robo-3 is a divergent member of the Robo family which instead of being a positive regulator of Slit responsiveness, antagonizes Slit responsiveness in precrossing axons. The Slit-Robo interaction is mediated by the second leucine-rich repeat (LRR) domain of Slit and the two N-terminal Ig domains of Robo, Ig1 and Ig2. The primary Robo binding site for Slit-2 has been shown by surface plasmon resonance experiments and mutational analysis to be the Ig1 domain, while the Ig2 domain has been proposed to harbor a weak secondary binding site. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409389 [Multi-domain] Cd Length: 87 Bit Score: 61.65 E-value: 1.48e-11

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|.
gi 2217265369  444 LDC-PFFGSPIPTLRWFKNGQGSNLDGGNYHVYENGSLEIKMIRKEDQGIYTCVATNILGKAENQV-RLEV 512
Cdd:cd05724     17 LECsPPRGHPEPTVSWRKDGQPLNLDNERVRIVDDGNLLIAEARKSDEGTYKCVATNMVGERESRAaRLSV 87

Fifth immunoglobulin (Ig) domain of contactin; The members here are composed of the fifth immunoglobulin (Ig) domain of contactins. Contactins are neural cell adhesion molecules and are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. The first four Ig domains form the intermolecular binding fragment, which arranges as a compact U-shaped module via contacts between Ig domains 1 and 4, and between Ig domains 2 and 3. Contactin-2 (TAG-1, axonin-1) may play a part in the neuronal processes of neurite outgrowth, axon guidance and fasciculation, and neuronal migration. This group also includes contactin-1 and contactin-5. The different contactins show different expression patterns in the central nervous system. During development and in adulthood, contactin-2 is transiently expressed in subsets of central and peripheral neurons. Contactin-5 is expressed specifically in the rat postnatal nervous system, peaking at about 3 weeks postnatal, and a lack of contactin-5 (NB-2) results in an impairment of neuronal activity in the rat auditory system. Contactin-5 is highly expressed in the adult human brain in the occipital lobe and in the amygdala. Contactin-1 is differentially expressed in tumor tissues and may, through a RhoA mechanism, facilitate invasion and metastasis of human lung adenocarcinoma.

Pssm-ID: 409358 [Multi-domain] Cd Length: 89 Bit Score: 61.71 E-value: 1.49e-11

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  431 NQLIRVILYNRTR---LDCPFFGSPIPTLRWFKNGQgsNL-DGGNYHVYENGSLEIKMIRKEDQGIYTCVATNILGKAEN 506
Cdd:cd04969      6 NPVKKKILAAKGGdviIECKPKASPKPTISWSKGTE--LLtNSSRICILPDGSLKIKNVTKSDEGKYTCFAVNFFGKANS 83


                   ....*.
gi 2217265369  507 QVRLEV 512
Cdd:cd04969     84 TGSLSV 89

Fourth immunoglobulin (Ig)-like domain of hemolin, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the fourth immunoglobulin (Ig)-like domain of hemolin and similar proteins. Hemolin, an insect immunoglobulin superfamily (IgSF) member containing four Ig-like domains, is a lipopolysaccharide-binding immune protein induced during bacterial infection. Hemolin shares significant sequence similarity with the first four Ig-like domains of the transmembrane cell adhesion molecules (CAMs) of the L1 family. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. The fourth Ig-like domain of hemolin is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set domains, members of the I-set have a discontinuous A strand but lack a C" strand. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409570 [Multi-domain] Cd Length: 88 Bit Score: 61.64 E-value: 1.66e-11

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  424 PRMLSPRNQLIRVILYNRTRLDCPFFGSPIPTLRWFKNGQGSNLDGGNYHVyENGSLEIKMIRKEDQGIYTCVATNILGK 503
Cdd:cd20978      1 PKFIQKPEKNVVVKGGQDVTLPCQVTGVPQPKITWLHNGKPLQGPMERATV-EDGTLTIINVQPEDTGYYGCVATNEIGD 79


                   ....*....
gi 2217265369  504 AENQVRLEV 512
Cdd:cd20978     80 IYTETLLHV 88

Second immunoglobulin (Ig)-like domain of hemolin, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the second immunoglobulin (Ig)-like domain of hemolin and similar proteins. Hemolin, an insect immunoglobulin superfamily (IgSF) member containing four Ig-like domains, is a lipopolysaccharide-binding immune protein induced during bacterial infection. Hemolin shares significant sequence similarity with the first four Ig-like domains of the transmembrane cell adhesion molecules (CAMs) of the L1 family. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structures of this group show that the second Ig domain lacks this strand and thus belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules, including vascular (VCAM), intercellular (ICAM), neural (NCAM) and mucosal addressin (MADCAM) cell adhesion molecules, as well as junction adhesion molecules (JAM).

Pssm-ID: 409557 Cd Length: 101 Bit Score: 61.88 E-value: 1.69e-11

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  148 EGAPLTLQCNPPPGLPSPVIFW--MSSSMEPI---TQDKRVSQGHNGDLYFSNVMLQDMQTDYS--CNAR 210
Cdd:cd20965     16 EGKPFKLDCNVPPGYPKPTIEWkkQLVSDSSKadtILDRRITISPNGDLYFTNVTKEDVSTDYKyvCVAK 85

Fibronectin type 3 domain; One of three types of internal repeats found in the plasma protein fibronectin. Its tenth fibronectin type III repeat contains an RGD cell recognition sequence in a flexible loop between 2 strands. Approximately 2% of all animal proteins contain the FN3 repeat; including extracellular and intracellular proteins, membrane spanning cytokine receptors, growth hormone receptors, tyrosine phosphatase receptors, and adhesion molecules. FN3-like domains are also found in bacterial glycosyl hydrolases.

Pssm-ID: 238020 [Multi-domain] Cd Length: 93 Bit Score: 61.36 E-value: 2.69e-11

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  926 PSAPRRFRVRQPNLETINLEWDHPEHPNGIMIGYTLKYVAFNGTKVgkQIVENFSPNQTKFTVQRTDPVSRYRFTLSART 1005
Cdd:cd00063      1 PSPPTNLRVTDVTSTSVTLSWTPPEDDGGPITGYVVEYREKGSGDW--KEVEVTPGSETSYTLTGLKPGTEYEFRVRAVN 78

                           90
                   ....*....|..
gi 2217265369 1006 QVGSGEAVTEES 1017
Cdd:cd00063     79 GGGESPPSESVT 90

Immunoglobulin domain; This family contains immunoglobulin-like domains.

Pssm-ID: 464046 [Multi-domain] Cd Length: 78 Bit Score: 60.66 E-value: 2.82e-11

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369   34 PPTITKQSaKDHIVDPRDNILIECEAKGNPAPSFHWTRNSRFFNIAKDPRVSMRRRSGTLVIDFRSggrpEEYEGEYQCF 113
Cdd:pfam13927    1 KPVITVSP-SSVTVREGETVTLTCEATGSPPPTITWYKNGEPISSGSTRSRSLSGSNSTLTISNVT----RSDAGTYTCV 75


                   ...
gi 2217265369  114 ARN 116
Cdd:pfam13927   76 ASN 78

Immunoglobulin like; IG domains that cannot be classified into one of IGv1, IGc1, IGc2, IG.

Pssm-ID: 214653 [Multi-domain] Cd Length: 85 Bit Score: 60.60 E-value: 2.99e-11

                            10        20        30        40        50        60        70        80
                    ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369   522 PEDQVARRGTTVQLECRVKHDPSLklTVSWLKDD-EPLYIGNRMK----KEDDSLTIFGVAERDQGSYTCVASTELDQDL 596
Cdd:smart00410    1 PPSVTVKEGESVTLSCEASGSPPP--EVTWYKQGgKLLAESGRFSvsrsGSTSTLTISNVTPEDSGTYTCAATNSSGSAS 78


                    ....*..
gi 2217265369   597 AKAYLTV 603
Cdd:smart00410   79 SGTTLTV 85

Fibronectin type 3 domain; One of three types of internal repeat within the plasma protein, fibronectin. The tenth fibronectin type III repeat contains a RGD cell recognition sequence in a flexible loop between 2 strands. Type III modules are present in both extracellular and intracellular proteins.

Pssm-ID: 214495 [Multi-domain] Cd Length: 83 Bit Score: 59.94 E-value: 5.24e-11

                            10        20        30        40        50        60        70        80
                    ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369   622 PDRPRDLELTDLAERSVRLTWIP--GDANNSPITDYVVQFEEDQFQpgvWHDHSKyPGSVNSAVLR-LSPYVNYQFRVIA 698
Cdd:smart00060    1 PSPPSNLRVTDVTSTSVTLSWEPppDDGITGYIVGYRVEYREEGSE---WKEVNV-TPSSTSYTLTgLKPGTEYEFRVRA 76


                    ....*..
gi 2217265369   699 INEVGSS 705
Cdd:smart00060   77 VNGAGEG 83

Fourth Ig domain of the neural cell adhesion molecule contactin-2, and similar domains; The members here are composed of the fourth Ig domain of the neural cell adhesion molecule contactin-2. Contactins are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. Contactin-2 (also called TAG-1, axonin-1) facilitates cell adhesion by homophilic binding between molecules in apposed membranes. The first four Ig domains form the intermolecular binding fragment which arranges as a compact U-shaped module by contacts between Ig domains 1 and 4, and domains 2 and 3. It has been proposed that a linear zipper-like array forms, from contactin-2 molecules alternatively provided by the two apposed membranes.

Pssm-ID: 143205 [Multi-domain] Cd Length: 85 Bit Score: 59.92 E-value: 5.93e-11

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 2217265369  255 GMDLLLECIASGVPTPDIAWYKKGGDLPSDKaKFENFNKALRITNVSEEDSGEYFCLASNKMGSIRHTISVRV 327
Cdd:cd05728     14 GSSLRWECKASGNPRPAYRWLKNGQPLASEN-RIEVEAGDLRITKLSLSDSGMYQCVAENKHGTIYASAELAV 85

Fibronectin type 3 domain; One of three types of internal repeat within the plasma protein, fibronectin. The tenth fibronectin type III repeat contains a RGD cell recognition sequence in a flexible loop between 2 strands. Type III modules are present in both extracellular and intracellular proteins.

Pssm-ID: 214495 [Multi-domain] Cd Length: 83 Bit Score: 59.55 E-value: 6.82e-11

                            10        20        30        40        50        60        70        80
                    ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369   926 PSAPRRFRVRQPNLETINLEWDHPEHPNGImiGYTLKYVAFNGTKVGKQIVENFSPNQTKFTVQRTDPVSRYRFTLSART 1005
Cdd:smart00060    1 PSPPSNLRVTDVTSTSVTLSWEPPPDDGIT--GYIVGYRVEYREEGSEWKEVNVTPSSTSYTLTGLKPGTEYEFRVRAVN 78


                    ....*
gi 2217265369  1006 QVGSG 1010
Cdd:smart00060   79 GAGEG 83

Fourth immunoglobulin domain of the Drosophila melanogaster Dscam protein, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the fourth immunoglobulin domain of the Drosophila melanogaster Down syndrome cell adhesion molecule (DSCAM) protein and similar proteins. Down syndrome cell adhesion molecule (DSCAM) is a cell adhesion molecule that plays critical roles in neural development, including axon guidance and branching, axon target recognition, self-avoidance and synaptic formation. DSCAM belongs to the immunoglobulin superfamily and contributes to defects in the central nervous system in Down syndrome patients. Vertebrate DSCAMs differ from Drosophila Dscam1 in that they lack the extensive alternative splicing that occurs in the insect gene. Drosophila melanogaster Dscam has 38,016 isoforms generated by the alternative splicing of four variable exon clusters, which allows every neuron in the fly to display a distinctive set of Dscam proteins on its cell surface. Drosophila Dscam1 is a cell-surface protein that plays important roles in neural development and axon tiling of neurons. It is shown that thousands of isoforms bind themselves through specific homophilic (self-binding) interactions, a process which mediates cellular self-recognition. Drosophila Dscam2 is also alternatively spliced and plays a key role in the development of two visual system neurons, monopolar cells L1 and L2. This group is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand.

Pssm-ID: 409548 [Multi-domain] Cd Length: 96 Bit Score: 59.50 E-value: 1.03e-10

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  237 TPSFMYpqgTASSQMVLRGMDLLLECIASGVPTPDIAWYKKGGDLP-SDKAKFENF-------NKALRITNVSEEDSGEY 308
Cdd:cd20956      1 APVLLE---TFSEQTLQPGPSVSLKCVASGNPLPQITWTLDGFPIPeSPRFRVGDYvtsdgdvVSYVNISSVRVEDGGEY 77

                           90
                   ....*....|....*....
gi 2217265369  309 FCLASNKMGSIRHTISVRV 327
Cdd:cd20956     78 TCTATNDVGSVSHSARINV 96

Fourth Ig-like domain from smooth muscle myosin light chain kinase and similar domains ; a member of the I-set of IgSF domains; The members here are composed of the fourth immunoglobulin (Ig)-like domain from smooth muscle myosin light chain kinase (MYLK) and similar domains. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structure of this group shows that the fourth Ig-like domain from myosin light chain kinase lacks this strand and thus belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409568 [Multi-domain] Cd Length: 90 Bit Score: 58.80 E-value: 1.48e-10

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 2217265369  252 VLRGMDLLLECIASGVPTPDIAWYKKGGDLPSDKAKF--ENFNKALRITNVSEEDSGEYFCLASNKMGSIRHTISVRV 327
Cdd:cd20976     13 AVEGQDFVAQCSARGKPVPRITWIRNAQPLQYAADRStcEAGVGELHIQDVLPEDHGTYTCLAKNAAGQVSCSAWVTV 90

Immunoglobulin domain; This family contains immunoglobulin-like domains.

Pssm-ID: 464046 [Multi-domain] Cd Length: 78 Bit Score: 58.35 E-value: 1.54e-10

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 2217265369  423 PPRMLSPRNQLIrVILYNRTRLDCPFFGSPIPTLRWFKNGQ--GSNLDGGNYHVYENGSLEIKMIRKEDQGIYTCVATN 499
Cdd:pfam13927    1 KPVITVSPSSVT-VREGETVTLTCEATGSPPPTITWYKNGEpiSSGSTRSRSLSGSNSTLTISNVTRSDAGTYTCVASN 78

Sixth immunoglobulin (Ig) domain of contactin-2; The members here are composed of the sixth immunoglobulin (Ig) domain of the neural cell adhesion molecule contactin-2-like. Contactins are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. Contactin-2 (TAG-1, axonin-1) facilitates cell adhesion by homophilic binding between molecules in apposed membranes. It may play a part in the neuronal processes of neurite outgrowth, axon guidance and fasciculation, and neuronal migration. The first four Ig domains form the intermolecular binding fragment, which arranges as a compact U-shaped module by contacts between IG domains 1 and 4, and domains 2 and 3. The different contactins show different expression patterns in the central nervous system. During development and in adulthood, contactin-2 is transiently expressed in subsets of central and peripheral neurons. Contactin-2 is also expressed in retinal amacrine cells (AC) in the developing chick retina, corresponding to the period of formation and maturation of AC processes.

Pssm-ID: 409440 Cd Length: 102 Bit Score: 59.29 E-value: 1.58e-10

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  514 DPTRIYRMPEDQVARRGTTVQLECRVKHDPSLKLTVSWLKDDEPL--------YIGNRMKKEDDSLTIFGVAERDQGSYT 585
Cdd:cd05854      1 DATKITLAPSSADINQGENLTLQCHASHDPTMDLTFTWSLDDFPIdldkpnghYRRMEVKETIGDLVIVNAQLSHAGTYT 80

                           90
                   ....*....|....*...
gi 2217265369  586 CVASTELDQDLAKAYLTV 603
Cdd:cd05854     81 CTAQTVVDSASASATLVV 98

Seventh immunoglobulin domain of the Drosophila melanogaster Dscam protein, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the seventh immunoglobulin domain of the Drosophila melanogaster Down syndrome cell adhesion molecule (DSCAM) protein and similar proteins. Down syndrome cell adhesion molecule (DSCAM) is a cell adhesion molecule that plays critical roles in neural development, including axon guidance and branching, axon target recognition, self-avoidance and synaptic formation. DSCAM belongs to the immunoglobulin superfamily and contributes to defects in the central nervous system in Down syndrome patients. Vertebrate DSCAMs differ from Drosophila Dscam1 in that they lack the extensive alternative splicing that occurs in the insect gene. Drosophila melanogaster Dscam has 38,016 isoforms generated by the alternative splicing of four variable exon clusters, which allows every neuron in the fly to display a distinctive set of Dscam proteins on its cell surface. Drosophila Dscam1 is a cell-surface protein that plays important roles in neural development and axon tiling of neurons. It is shown that thousands of isoforms bind themselves through specific homophilic (self-binding) interactions, a process which mediates cellular self-recognition. Drosophila Dscam2 is also alternatively spliced and plays a key role in the development of two visual system neurons, monopolar cells L1 and L2. This group is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand.

Pssm-ID: 409546 [Multi-domain] Cd Length: 96 Bit Score: 58.09 E-value: 3.82e-10

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 2217265369  252 VLRGMDLLLECIASGVPTPDIAWYKKGGDLPSDKAKF--ENF-----NKALRITNVSEEDSGEYFCLASNKMGS 318
Cdd:cd20954     13 VAAGQDVMLHCQADGFPTPTVTWKKATGSTPGEYKDLlyDPNvrilpNGTLVFGHVQKENEGHYLCEAKNGIGS 86

Second immunoglobulin (Ig)-like domain of fibroblast growth factor (FGF) receptor, and similar domains; member of the I-set of IgSF domains; The members here are composed of the second immunoglobulin (Ig)-like domain of fibroblast growth factor (FGF) receptor. FGF receptors bind FGF signaling polypeptides. FGFs participate in multiple processes such as morphogenesis, development, and angiogenesis. FGFs bind to four FGF receptor tyrosine kinases (FGFR1, FGFR2, FGFR3, FGFR4). Receptor diversity is controlled by alternative splicing producing splice variants with different ligand binding characteristics and different expression patterns. FGFRs have an extracellular region comprised of three Ig-like domains, a single transmembrane helix, and an intracellular tyrosine kinase domain. Ligand binding and specificity reside in the Ig-like domains 2 and 3, and the linker region that connects these two. FGFR activation and signaling depend on FGF-induced dimerization, a process involving cell surface heparin or heparin sulfate proteoglycans. This group also contains fibroblast growth factor (FGF) receptor like-1(FGFRL1). FGFRL1 does not have a protein tyrosine kinase domain at its C-terminus; neither does its cytoplasmic domain appear to interact with a signaling partner. It has been suggested that FGFRL1 may not have any direct signaling function, but instead acts as a decoy receptor trapping FGFs and preventing them from binding other receptors.

Pssm-ID: 409393 [Multi-domain] Cd Length: 95 Bit Score: 57.61 E-value: 4.44e-10

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 2217265369  260 LECIASGVPTPDIAWYKKGGDLPSDKA----KFENFNKALRITNVSEEDSGEYFCLASNKMGSIRHTISVRV 327
Cdd:cd05729     24 LECGAGGNPMPNITWLKDGKEFKKEHRiggtKVEEKGWSLIIERAIPRDKGKYTCIVENEYGSINHTYDVDV 95

First immunoglobulin (Ig)-like constant domain in Robo (roundabout) receptors, and similar domains; The members here are composed of the first immunoglobulin (Ig)-like domain in Roundabout (Robo) receptors. Robo receptors play a role in the development of the central nervous system (CNS), and are receptors of Slit protein. Slit is a repellant secreted by the neural cells in the midline. Slit acts through Robo to prevent most neurons from crossing the midline from either side. Three mammalian Robo homologs (Robo1, Robo2, and Robo3), and three mammalian Slit homologs (Slit1, Slit2, Slit3), have been identified. Commissural axons, which cross the midline, express low levels of Robo; longitudinal axons, which avoid the midline, express high levels of Robo. Robo1, Robo2, and Robo3 are expressed by commissural neurons in the vertebrate spinal cord and Slit1, Slit2,and Slit3 are expressed at the ventral midline. Robo3 is a divergent member of the Robo family which instead of being a positive regulator of Slit responsiveness, antagonizes Slit responsiveness in precrossing axons. The Slit-Robo interaction is mediated by the second leucine-rich repeat (LRR) domain of Slit and the two N-terminal Ig domains of Robo, Ig1 and Ig2. The primary Robo binding site for Slit2 has been shown by surface plasmon resonance experiments and mutational analysis to be is the Ig1 domain, while the Ig2 domain has been proposed to harbor a weak secondary binding site.

Pssm-ID: 409490 [Multi-domain] Cd Length: 99 Bit Score: 57.95 E-value: 4.75e-10

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369   35 PTITKQSaKDHIVDPRDNILIECEAKGNPAPSFHWTRNSRFFNIAKDPRVSMRR--RSGTLV-IDFRSGGRPEEYEGEYQ 111
Cdd:cd07693      1 PRIVEHP-SDLIVSKGDPATLNCKAEGRPTPTIQWLKNGQPLETDKDDPRSHRIvlPSGSLFfLRVVHGRKGRSDEGVYV 79

                           90       100
                   ....*....|....*....|
gi 2217265369  112 CFARNKFGTALSNRIRLQVS 131
Cdd:cd07693     80 CVAHNSLGEAVSRNASLEVA 99

First immunoglobulin (Ig) domain of contactin-5; member of the I-set of Ig superfamily domains; The members here are composed of the first immunoglobulin (Ig) domain of the neural cell adhesion molecule contactin-5. Contactins are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains, anchored to the membrane by glycosylphosphatidylinositol. The different contactins show different expression patterns in the central nervous system. In rats, a lack of contactin-5 (NB-2) results in an impairment of the neuronal activity in the auditory system. Contactin-5 is expressed specifically in the postnatal nervous system, peaking at about 3 weeks postnatal. Contactin-5 is highly expressed in the adult human brain in the occipital lobe and in the amygdala; lower levels of expression have been detected in the corpus callosum, caudate nucleus, and spinal cord. This group belongs to the I-set of IgSF domains.

Pssm-ID: 409435 Cd Length: 96 Bit Score: 57.65 E-value: 5.27e-10

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369   44 DHIVDPRDN----ILIECEAKGNPAPSFHWTRNSRFFNIAKDPRVSMrrRSGTLVIDfrsggRPEEYE--GEYQCFARNK 117
Cdd:cd05848      9 DDAIFPTDSdekkVILNCEARGNPVPTYRWLRNGTEIDTESDYRYSL--IDGNLIIS-----NPSEVKdsGRYQCLATNS 81

                           90
                   ....*....|..
gi 2217265369  118 FGTALSNRIRLQ 129
Cdd:cd05848     82 IGSILSREALLQ 93

Fifth Ig-like domain of Roundabout (Robo) homolog 1/2, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the fifth Ig-like domain of Roundabout (Robo) homolog 1/2 and similar domains. Robo receptors play a role in the development of the central nervous system (CNS), and are receptors of Slit protein. Slit is a repellant secreted by the neural cells in the midline. Slit acts through Robo to prevent most neurons from crossing the midline from either side. Three mammalian Robo homologs (Robo1, -2, and -3), and three mammalian Slit homologs (Slit-1,-2, -3), have been identified. Commissural axons, which cross the midline, express low levels of Robo; longitudinal axons, which avoid the midline, express high levels of Robo. Robo1, -2, and -3 are expressed by commissural neurons in the vertebrate spinal cord and Slits 1, -2, -3 are expressed at the ventral midline. Robo-3 is a divergent member of the Robo family which instead of being a positive regulator of slit responsiveness, antagonizes slit responsiveness in precrossing axons. The Slit-Robo interaction is mediated by the second leucine-rich repeat (LRR) domain of Slit and the two N-terminal Ig domains of Robo, Ig1 and Ig2. The primary Robo binding site for Slit2 has been shown by surface plasmon resonance experiments and mutational analysis to be is the Ig1 domain, while the Ig2 domain has been proposed to harbor a weak secondary binding site. The fifth Ig-like domain of Robo 1 and 2 is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors

Pssm-ID: 409544 [Multi-domain] Cd Length: 87 Bit Score: 57.12 E-value: 6.67e-10

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  522 PEDQVARRGTTVQLECRVKHDPSLklTVSWLKDDEPLYIGN-RMKK-EDDSLTIFGVAERDQGSYTCVASTELDQDLAKA 599
Cdd:cd20952      6 PQNQTVAVGGTVVLNCQATGEPVP--TISWLKDGVPLLGKDeRITTlENGSLQIKGAEKSDTGEYTCVALNLSGEATWSA 83


                   ....
gi 2217265369  600 YLTV 603
Cdd:cd20952     84 VLDV 87

Second immunoglobulin (Ig)-like domain of fibroblast growth factor (FGF) receptor_like-1(FGFRL1); member of the I-set of IgSF domains; The members here are composed of the second immunoglobulin (Ig)-like domain of fibroblast growth factor (FGF) receptor like-1(FGFRL1). FGFRL1 is comprised of a signal peptide, three extracellular Ig-like modules, a transmembrane segment, and a short intracellular domain. FGFRL1 is expressed preferentially in skeletal tissues. Similar to FGF receptors, the expressed protein interacts specifically with heparin and with FGF2. FGFRL1 does not have a protein tyrosine kinase domain at its C-terminus; neither does its cytoplasmic domain appear to interact with a signaling partner. It has been suggested that FGFRL1 may not have any direct signaling function, but instead acts as a decoy receptor trapping FGFs and preventing them from binding other receptors.

Pssm-ID: 409442 Cd Length: 92 Bit Score: 56.79 E-value: 1.04e-09

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  243 PQGTASSQMVLR------GMDLLLECIASGVPTPDIAWYKKGGDLPSDKAKFENFNK-ALRITNVSEEDSGEYFCLASNK 315
Cdd:cd05856      1 PRFTQPAKMRRRviarpvGSSVRLKCVASGNPRPDITWLKDNKPLTPPEIGENKKKKwTLSLKNLKPEDSGKYTCHVSNR 80

                           90
                   ....*....|..
gi 2217265369  316 MGSIRHTISVRV 327
Cdd:cd05856     81 AGEINATYKVDV 92

Second Ig-like domain of the giant muscle protein titin Z1z2 in the sarcomeric Z-disk, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the second immunoglobulin (Ig)-like domain of the giant muscle protein titin Z1z2 in the sarcomeric Z-disk and similar proteins. Titin is a key component in the assembly and functioning of vertebrate striated muscles. By providing connections at the level of individual microfilaments, it contributes to the fine balance of forces between the two halves of the sarcomere. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structure of the titin Z1z2 lacks this strand and thus it belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409564 [Multi-domain] Cd Length: 91 Bit Score: 56.44 E-value: 1.05e-09

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 2217265369  249 SQMVLRGMDLLLECIASGVPTPDIAWYKKGGDL---PSDKAKFENFNKALRITNVSEEDSGEYFCLASNKMGS 318
Cdd:cd20972     10 SQEVAEGSKVRLECRVTGNPTPVVRWFCEGKELqnsPDIQIHQEGDLHSLIIAEAFEEDTGRYSCLATNSVGS 82

Immunoglobulin domain I1 of the titin I-band and similar proteins; a member of the I-set of IgSF domains; The members here are composed of the immunoglobulin domain I1 of the titin I-band and similar proteins. Titin is a key component in the assembly and functioning of vertebrate striated muscles. By providing connections at the level of individual microfilaments, it contributes to the fine balance of forces between the two halves of the sarcomere. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. The two sheets are linked together by a conserved disulfide bond between B strand and F strand. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. The Ig I1 domain of the titin I-band is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409543 [Multi-domain] Cd Length: 94 Bit Score: 56.66 E-value: 1.19e-09

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 2217265369  345 GEDGRLVCRANGNPKPTVQWMVNGEPLQSAPPNPNREVAGD----TIIFRDTQISSRAVYQCNTSNEHGYLLANAFVSV 419
Cdd:cd20951     15 KSDAKLRVEVQGKPDPEVKWYKNGVPIDPSSIPGKYKIESEygvhVLHIRRVTVEDSAVYSAVAKNIHGEASSSASVVV 93

agrin-responsive first immunoglobulin-like domains (Ig1) of the MuSK ectodomain; a member of the I-set of IgSF domains; The members here are composed of the first immunoglobulin-like domains (Ig1) of the Muscle-specific kinase (MuSK). MuSK is a receptor tyrosine kinase specifically expressed in skeletal muscle, where it plays a central role in the formation and maintenance of the neuromuscular junction (NMJ). MuSK is activated by agrin, a neuron-derived heparan sulfate proteoglycan. The activation of MUSK in myotubes regulates the formation of NMJs through the regulation of different processes including the specific expression of genes in subsynaptic nuclei, the reorganization of the actin cytoskeleton and the clustering of the acetylcholine receptors (AChR) in the postsynaptic membrane. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structure of the MuSK lacks this strand and thus it belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409562 [Multi-domain] Cd Length: 92 Bit Score: 56.36 E-value: 1.47e-09

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 2217265369  252 VLRGMDLLLECIASGVPTPDIAWYKKGG--DLPSDKAKFENFNKALRITNVSEEDSGEYFCLASNKM-GSIRHTISVRV 327
Cdd:cd20970     14 AREGENATFMCRAEGSPEPEISWTRNGNliIEFNTRYIVRENGTTLTIRNIRRSDMGIYLCIASNGVpGSVEKRITLQV 92

Immunoglobulin domain; This family contains immunoglobulin-like domains.

Pssm-ID: 464046 [Multi-domain] Cd Length: 78 Bit Score: 55.65 E-value: 1.47e-09

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 2217265369  522 PEDQVARRGTTVQLECRVKHDPslKLTVSWLKDDEPLYIGNRMKKEDD----SLTIFGVAERDQGSYTCVAS 589
Cdd:pfam13927    8 PSSVTVREGETVTLTCEATGSP--PPTITWYKNGEPISSGSTRSRSLSgsnsTLTISNVTRSDAGTYTCVAS 77

Third immunoglobulin (Ig)-like domain of Neural Cell Adhesion Molecule 1 (NCAM-1); member of the I-set of IgSF domains; The members here are composed of the third immunoglobulin (Ig)-like domain of Neural Cell Adhesion Molecule (NCAM-1). NCAM plays important roles in the development and regeneration of the central nervous system, in synaptogenesis and neural migration. NCAM mediates cell-cell and cell-substratum recognition and adhesion via homophilic (NCAM-NCAM), and heterophilic (NCAM-non-NCAM), interactions. NCAM is expressed as three major isoforms having different intracellular extensions. The extracellular portion of NCAM has five N-terminal Ig-like domains and two fibronectin type III domains. The double zipper adhesion complex model for NCAM homophilic binding involves Ig1, Ig2, and Ig3. By this model, Ig1 and Ig2 mediate dimerization of NCAM molecules situated on the same cell surface (cis interactions), and Ig3 domains mediate interactions between NCAM molecules expressed on the surface of opposing cells (trans interactions) through binding to the Ig1 and Ig2 domains. The adhesive ability of NCAM is modulated by the addition of polysialic acid chains to the fifth Ig-like domain.

Pssm-ID: 143207 [Multi-domain] Cd Length: 95 Bit Score: 56.09 E-value: 1.51e-09

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 2217265369  255 GMDLLLECIASGVPTPDIAWYKKGGDLPSDKAKFeNFNK---ALRITNVSEEDSGEYFCLASNKMGSIRHTISVRVKA 329
Cdd:cd05730     18 GQSVTLACDADGFPEPTMTWTKDGEPIESGEEKY-SFNEdgsEMTILDVDKLDEAEYTCIAENKAGEQEAEIHLKVFA 94

Fifth immunoglobulin domain of the Drosophila melanogaster Dscam protein, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the fifth immunoglobulin domain of the Drosophila melanogaster Down syndrome cell adhesion molecule (DSCAM) protein and similar proteins. Down syndrome cell adhesion molecule (DSCAM) is a cell adhesion molecule that plays critical roles in neural development, including axon guidance and branching, axon target recognition, self-avoidance and synaptic formation. DSCAM belongs to the immunoglobulin superfamily and contributes to defects in the central nervous system in Down syndrome patients. Vertebrate DSCAMs differ from Drosophila Dscam1 in that they lack the extensive alternative splicing that occurs in the insect gene. Drosophila melanogaster Dscam has 38,016 isoforms generated by the alternative splicing of four variable exon clusters, which allows every neuron in the fly to display a distinctive set of Dscam proteins on its cell surface. Drosophila Dscam1 is a cell-surface protein that plays important roles in neural development and axon tiling of neurons. It is shown that thousands of isoforms bind themselves through specific homophilic (self-binding) interactions, a process which mediates cellular self-recognition. Drosophila Dscam2 is also alternatively spliced and plays a key role in the development of two visual system neurons, monopolar cells L1 and L2. This group is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand.

Pssm-ID: 409550 [Multi-domain] Cd Length: 89 Bit Score: 56.04 E-value: 1.63e-09

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|.
gi 2217265369  441 RTRLDCPFFGSPIPTLRWFKNGQgsNL-DGGNYHVYENGSLEIKMI-RKEDQGIYTCVATN 499
Cdd:cd20958     17 TLRLHCPVAGYPISSITWEKDGR--RLpLNHRQRVFPNGTLVIENVqRSSDEGEYTCTARN 75

Third immunoglobulin (Ig)-like domain of peroxidasin; The members here are composed of the third immunoglobulin (Ig)-like domain in peroxidasin. Peroxidasin has a peroxidase domain and interacting extracellular motifs containing four Ig-like domains. It has been suggested that peroxidasin is secreted and has functions related to the stabilization of the extracellular matrix. It may play a part in various other important processes such as removal and destruction of cells which have undergone programmed cell death and protection of the organism against non-self.

Pssm-ID: 143222 [Multi-domain] Cd Length: 74 Bit Score: 55.33 E-value: 1.66e-09

                           10        20        30        40        50
                   ....*....|....*....|....*....|....*....|....*....|....*....
gi 2217265369  262 CIASGVPTPDIAWYKKGGDLPSDKAKFENFNKALRITNVSEEDSGEYFCLASNKMGSIR 320
Cdd:cd05745      9 CEAQGYPQPVIAWTKGGSQLSVDRRHLVLSSGTLRISRVALHDQGQYECQAVNIVGSQR 67

Fifth immunoglobulin (Ig) domain of contactin; The members here are composed of the fifth immunoglobulin (Ig) domain of contactins. Contactins are neural cell adhesion molecules and are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. The first four Ig domains form the intermolecular binding fragment, which arranges as a compact U-shaped module via contacts between Ig domains 1 and 4, and between Ig domains 2 and 3. Contactin-2 (TAG-1, axonin-1) may play a part in the neuronal processes of neurite outgrowth, axon guidance and fasciculation, and neuronal migration. This group also includes contactin-1 and contactin-5. The different contactins show different expression patterns in the central nervous system. During development and in adulthood, contactin-2 is transiently expressed in subsets of central and peripheral neurons. Contactin-5 is expressed specifically in the rat postnatal nervous system, peaking at about 3 weeks postnatal, and a lack of contactin-5 (NB-2) results in an impairment of neuronal activity in the rat auditory system. Contactin-5 is highly expressed in the adult human brain in the occipital lobe and in the amygdala. Contactin-1 is differentially expressed in tumor tissues and may, through a RhoA mechanism, facilitate invasion and metastasis of human lung adenocarcinoma.

Pssm-ID: 409358 [Multi-domain] Cd Length: 89 Bit Score: 55.93 E-value: 1.77e-09

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 2217265369  252 VLRGMDLLLECIASGVPTPDIAWYKKGGDLPSDKAKFENFNKALRITNVSEEDSGEYFCLASNKMGSIRHTISVRV 327
Cdd:cd04969     14 AAKGGDVIIECKPKASPKPTISWSKGTELLTNSSRICILPDGSLKIKNVTKSDEGKYTCFAVNFFGKANSTGSLSV 89

Immunoglobulin domain; This family contains immunoglobulin-like domains.

Pssm-ID: 464046 [Multi-domain] Cd Length: 78 Bit Score: 55.26 E-value: 1.95e-09

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 2217265369  336 EPKNLILAPGEDGRLVCRANGNPKPTVQWMVNGEPLQSAPPNPNREVAGD-TIIFRDTQISSRAVYQCNTSN 406
Cdd:pfam13927    7 SPSSVTVREGETVTLTCEATGSPPPTITWYKNGEPISSGSTRSRSLSGSNsTLTISNVTRSDAGTYTCVASN 78

Fifth Ig-like domain of Roundabout (Robo) homolog 1/2, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the fifth Ig-like domain of Roundabout (Robo) homolog 1/2 and similar domains. Robo receptors play a role in the development of the central nervous system (CNS), and are receptors of Slit protein. Slit is a repellant secreted by the neural cells in the midline. Slit acts through Robo to prevent most neurons from crossing the midline from either side. Three mammalian Robo homologs (Robo1, -2, and -3), and three mammalian Slit homologs (Slit-1,-2, -3), have been identified. Commissural axons, which cross the midline, express low levels of Robo; longitudinal axons, which avoid the midline, express high levels of Robo. Robo1, -2, and -3 are expressed by commissural neurons in the vertebrate spinal cord and Slits 1, -2, -3 are expressed at the ventral midline. Robo-3 is a divergent member of the Robo family which instead of being a positive regulator of slit responsiveness, antagonizes slit responsiveness in precrossing axons. The Slit-Robo interaction is mediated by the second leucine-rich repeat (LRR) domain of Slit and the two N-terminal Ig domains of Robo, Ig1 and Ig2. The primary Robo binding site for Slit2 has been shown by surface plasmon resonance experiments and mutational analysis to be is the Ig1 domain, while the Ig2 domain has been proposed to harbor a weak secondary binding site. The fifth Ig-like domain of Robo 1 and 2 is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors

Pssm-ID: 409544 [Multi-domain] Cd Length: 87 Bit Score: 55.58 E-value: 2.13e-09

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  250 QMVLRGMDLLLECIASGVPTPDIAWYKKGGDLPSDKAKFENF-NKALRITNVSEEDSGEYFCLASNKMGS 318
Cdd:cd20952      9 QTVAVGGTVVLNCQATGEPVPTISWLKDGVPLLGKDERITTLeNGSLQIKGAEKSDTGEYTCVALNLSGE 78

Immunoglobulin (Ig)-like ectodomain of the LRIG1 (Leucine-rich Repeats And Immunoglobulin-like Domains Protein 1) and similar proteins; member of the I-set of IgSF domains; The members here are composed of subgroup of the immunoglobulin (Ig) domain found in the Ig superfamily. The Ig superfamily is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. A predominant feature of most Ig domains is a disulfide bridge connecting the two beta-sheets with a tryptophan residue packed against the disulfide bond. The ectodomain of LRIG1 has two distinct regions: the proposed 15 LRRs and three Ig-like domains closer to the membrane. LRIG1 has been reported to interact with many receptor tyrosine kinases, GDNF/c-Ret, E-cadherin, JAK/STAT, c-Met, and the EGFR family signaling systems. Immunoglobulin Superfamily (IgSF) domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. The structure of the LRIG1 extracellular Ig domain lacks a C" strand and thus is better described as a member of the I-set of IgSF domains.

Pssm-ID: 409420 [Multi-domain] Cd Length: 91 Bit Score: 55.70 E-value: 2.42e-09

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|....
gi 2217265369  260 LECIASGVPTPDIAWYKKGG-DLPSDKAKFENF---NKALRITNVSEEDSGEYFCLASNKMGSI 319
Cdd:cd05763     19 LECAATGHPTPQIAWQKDGGtDFPAARERRMHVmpeDDVFFIVDVKIEDTGVYSCTAQNSAGSI 82

Fibronectin type III domain;

Pssm-ID: 394996 [Multi-domain] Cd Length: 85 Bit Score: 55.11 E-value: 3.35e-09

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  927 SAPRRFRVRQPNLETINLEWDHPEHPNGIMIGYTLKYVAFNGTKVGKQIVEnfSPNQTKFTVQRTDPVSRYRFTLSARTQ 1006
Cdd:pfam00041    1 SAPSNLTVTDVTSTSLTVSWTPPPDGNGPITGYEVEYRPKNSGEPWNEITV--PGTTTSVTLTGLKPGTEYEVRVQAVNG 78


                   ....*
gi 2217265369 1007 VGSGE 1011
Cdd:pfam00041   79 GGEGP 83

First immunoglobulin (Ig)-like domain in neogenin, and similar domains; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the first immunoglobulin (Ig)-like domain in neogenin and related proteins. Neogenin is a cell surface protein which is expressed in the developing nervous system of vertebrate embryos in the growing nerve cells. It is also expressed in other embryonic tissues and may play a general role in developmental processes such as cell migration, cell-cell recognition, and tissue growth regulation. Included in this group is the tumor suppressor protein DCC which is deleted in colorectal carcinoma. DCC and neogenin each have four Ig-like domains followed by six fibronectin type III domains, a transmembrane domain, and an intracellular domain. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409387 Cd Length: 97 Bit Score: 55.18 E-value: 3.85e-09

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369   50 RDNILIECEAKGNPAPSFHWTRNSRFFNIAKDPRVSMrRRSGTLVID---FRSGGRPEeyEGEYQCFARNK-FGTALSNR 125
Cdd:cd05722     16 GGPVVLNCSAESDPPPKIEWKKDGVLLNLVSDERRQQ-LPNGSLLITsvvHSKHNKPD--EGFYQCVAQNEsLGSIVSRT 92


                   ....*
gi 2217265369  126 IRLQV 130
Cdd:cd05722     93 ARVTV 97

Immunoglobulin domain; The members here are composed of the immunoglobulin (Ig) domain found in the Ig superfamily. The Ig superfamily is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. Members of this group are components of immunoglobulin, neuroglia, cell surface glycoproteins, including T-cell receptors, CD2, CD4, CD8, and membrane glycoproteins, including butyrophilin and chondroitin sulfate proteoglycan core protein. A predominant feature of most Ig domains is a disulfide bridge connecting the two beta-sheets with a tryptophan residue packed against the disulfide bond. Ig superfamily (IgSF) domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Typically, the V-set domains have A, B, E, and D strands in one sheet and A', G, F, C, C' and C" in the other. The structures in C1-set are smaller than those in the V-set; they have one beta sheet that is formed by strands A, B, E, and D and the other by strands G, F, C, and C'. Moreover, a C1-set Ig domain contains a short C' strand (three residues) and lacks A' and C" strand. Unlike other Ig domain sets, C2-set structures do not have a D strand. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409353 [Multi-domain] Cd Length: 70 Bit Score: 54.26 E-value: 3.92e-09

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|..
gi 2217265369  349 RLVCRANGNPKPTVQWMVNGEPLQSAPPNPNREVAGD-TIIFRDTQISSRAVYQCNTSNEHG 409
Cdd:cd00096      2 TLTCSASGNPPPTITWYKNGKPLPPSSRDSRRSELGNgTLTISNVTLEDSGTYTCVASNSAG 63

Fibronectin type 3 domain [General function prediction only];

Pssm-ID: 442628 [Multi-domain] Cd Length: 603 Bit Score: 60.79 E-value: 4.31e-09

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  596 LAKAYLTVLADQATPTNRLAALPKGRPDRPRDLELTDLAERSVRLTWIPGDANNSPITDYVVQFEEDQFQPGVwhDHSKY 675
Cdd:COG3401    111 LTSSDEVPSPAVGTATTATAVAGGAATAGTYALGAGLYGVDGANASGTTASSVAGAGVVVSPDTSATAAVATT--SLTVT 188

                           90       100       110       120       130       140       150       160
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  676 PGSVNSAVLRLSPYVNYQFRVIAINEVGSSHPSlPSERYRTSGAPPESnPGDVKGEGTRKNNMEITWTPMNATSAFGpnl 755
Cdd:COG3401    189 STTLVDGGGDIEPGTTYYYRVAATDTGGESAPS-NEVSVTTPTTPPSA-PTGLTATADTPGSVTLSWDPVTESDATG--- 263

                          170       180       190       200       210       220       230       240
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  756 rYIVKwRRRETREAWNNV-TVWGSRYVV-----GQTpvyvpYEIRVQAENDFGKGPEPESVIGYSGEDYPRAAPTEVKVR 829
Cdd:COG3401    264 -YRVY-RSNSGDGPFTKVaTVTTTSYTDtgltnGTT-----YYYRVTAVDAAGNESAPSNVVSVTTDLTPPAAPSGLTAT 336

                          250       260       270
                   ....*....|....*....|....*....|....*
gi 2217265369  830 VMNSTAISLQWNRVYSDTVQGqlreYRAYYWRESS 864
Cdd:COG3401    337 AVGSSSITLSWTASSDADVTG----YNVYRSTSGG 367

agrin-responsive first immunoglobulin-like domains (Ig1) of the MuSK ectodomain; a member of the I-set of IgSF domains; The members here are composed of the first immunoglobulin-like domains (Ig1) of the Muscle-specific kinase (MuSK). MuSK is a receptor tyrosine kinase specifically expressed in skeletal muscle, where it plays a central role in the formation and maintenance of the neuromuscular junction (NMJ). MuSK is activated by agrin, a neuron-derived heparan sulfate proteoglycan. The activation of MUSK in myotubes regulates the formation of NMJs through the regulation of different processes including the specific expression of genes in subsynaptic nuclei, the reorganization of the actin cytoskeleton and the clustering of the acetylcholine receptors (AChR) in the postsynaptic membrane. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structure of the MuSK lacks this strand and thus it belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409562 [Multi-domain] Cd Length: 92 Bit Score: 54.82 E-value: 4.34e-09

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|.
gi 2217265369  444 LDCPFFGSPIPTLRWFKNGQGSNLDGGNYHVYENGS-LEIKMIRKEDQGIYTCVATN-ILGKAENQVRLEV 512
Cdd:cd20970     22 FMCRAEGSPEPEISWTRNGNLIIEFNTRYIVRENGTtLTIRNIRRSDMGIYLCIASNgVPGSVEKRITLQV 92

Fourth immunoglobulin (Ig)-like domain of hemolin, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the fourth immunoglobulin (Ig)-like domain of hemolin and similar proteins. Hemolin, an insect immunoglobulin superfamily (IgSF) member containing four Ig-like domains, is a lipopolysaccharide-binding immune protein induced during bacterial infection. Hemolin shares significant sequence similarity with the first four Ig-like domains of the transmembrane cell adhesion molecules (CAMs) of the L1 family. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. The fourth Ig-like domain of hemolin is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set domains, members of the I-set have a discontinuous A strand but lack a C" strand. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409570 [Multi-domain] Cd Length: 88 Bit Score: 54.32 E-value: 5.72e-09

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 2217265369  252 VLRGMDLLLECIASGVPTPDIAWYKKGGDL--PSDKAKFENFnkALRITNVSEEDSGEYFCLASNKMGSIRHTISVRV 327
Cdd:cd20978     13 VKGGQDVTLPCQVTGVPQPKITWLHNGKPLqgPMERATVEDG--TLTIINVQPEDTGYYGCVATNEIGDIYTETLLHV 88

Immunoglobulin I-set domain;

Pssm-ID: 400151 [Multi-domain] Cd Length: 90 Bit Score: 54.19 E-value: 6.82e-09

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  331 PYWLDEPKNLILAPGEDGRLVCRANGNPKPTVQWMVNGEPLQSAPPNPNREVAGD-TIIFRDTQISSRAVYQCNTSNEHG 409
Cdd:pfam07679    1 PKFTQKPKDVEVQEGESARFTCTVTGTPDPEVSWFKDGQPLRSSDRFKVTYEGGTyTLTISNVQPDDSGKYTCVATNSAG 80

                           90
                   ....*....|
gi 2217265369  410 YLLANAFVSV 419
Cdd:pfam07679   81 EAEASAELTV 90

Third immunoglobulin (Ig) domain of contactin-1; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the third immunoglobulin (Ig) domain of the neural cell adhesion molecule contactin-1. Contactins are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. Contactin-1 is differentially expressed in tumor tissues and may through a RhoA mechanism, facilitate invasion and metastasis of human lung adenocarcinoma. This group belongs to the I-set of IgSF domains.

Pssm-ID: 143259 Cd Length: 88 Bit Score: 53.87 E-value: 7.75e-09

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 2217265369  253 LRGMDLLLECIASGVPTPDIAWYKKGGDLPSdKAKFENFNKALRITNVSEEDSGEYFCLASNKMGSIRHTISVRVK 328
Cdd:cd05851     14 LKGQNVTLECFALGNPVPVIRWRKILEPMPA-TAEISMSGAVLKIFNIQPEDEGTYECEAENIKGKDKHQARVYVQ 88

First immunoglobulin (Ig)-like constant domain in Robo (roundabout) receptors, and similar domains; The members here are composed of the first immunoglobulin (Ig)-like domain in Roundabout (Robo) receptors. Robo receptors play a role in the development of the central nervous system (CNS), and are receptors of Slit protein. Slit is a repellant secreted by the neural cells in the midline. Slit acts through Robo to prevent most neurons from crossing the midline from either side. Three mammalian Robo homologs (Robo1, Robo2, and Robo3), and three mammalian Slit homologs (Slit1, Slit2, Slit3), have been identified. Commissural axons, which cross the midline, express low levels of Robo; longitudinal axons, which avoid the midline, express high levels of Robo. Robo1, Robo2, and Robo3 are expressed by commissural neurons in the vertebrate spinal cord and Slit1, Slit2,and Slit3 are expressed at the ventral midline. Robo3 is a divergent member of the Robo family which instead of being a positive regulator of Slit responsiveness, antagonizes Slit responsiveness in precrossing axons. The Slit-Robo interaction is mediated by the second leucine-rich repeat (LRR) domain of Slit and the two N-terminal Ig domains of Robo, Ig1 and Ig2. The primary Robo binding site for Slit2 has been shown by surface plasmon resonance experiments and mutational analysis to be is the Ig1 domain, while the Ig2 domain has been proposed to harbor a weak secondary binding site.

Pssm-ID: 409490 [Multi-domain] Cd Length: 99 Bit Score: 53.71 E-value: 1.20e-08

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  331 PYWLDEPKNLILAPGEDGRLVCRANGNPKPTVQWMVNGEPLQS--APPNPNREVAGDTIIFRDTQISSR------AVYQC 402
Cdd:cd07693      1 PRIVEHPSDLIVSKGDPATLNCKAEGRPTPTIQWLKNGQPLETdkDDPRSHRIVLPSGSLFFLRVVHGRkgrsdeGVYVC 80


                   ....*..
gi 2217265369  403 NTSNEHG 409
Cdd:cd07693     81 VAHNSLG 87

Immunoglobulin domain; The members here are composed of the immunoglobulin (Ig) domain found in the Ig superfamily. The Ig superfamily is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. Members of this group are components of immunoglobulin, neuroglia, cell surface glycoproteins, including T-cell receptors, CD2, CD4, CD8, and membrane glycoproteins, including butyrophilin and chondroitin sulfate proteoglycan core protein. A predominant feature of most Ig domains is a disulfide bridge connecting the two beta-sheets with a tryptophan residue packed against the disulfide bond. Ig superfamily (IgSF) domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Typically, the V-set domains have A, B, E, and D strands in one sheet and A', G, F, C, C' and C" in the other. The structures in C1-set are smaller than those in the V-set; they have one beta sheet that is formed by strands A, B, E, and D and the other by strands G, F, C, and C'. Moreover, a C1-set Ig domain contains a short C' strand (three residues) and lacks A' and C" strand. Unlike other Ig domain sets, C2-set structures do not have a D strand. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409353 [Multi-domain] Cd Length: 70 Bit Score: 52.72 E-value: 1.23e-08

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|....
gi 2217265369  533 VQLECRVKHDPslKLTVSWLKDDEPL----YIGNRMKKEDDSLTIFGVAERDQGSYTCVASTEL 592
Cdd:cd00096      1 VTLTCSASGNP--PPTITWYKNGKPLppssRDSRRSELGNGTLTISNVTLEDSGTYTCVASNSA 62

Immunoglobulin (Ig)-like domain in neuregulins; The members here are composed of the immunoglobulin (Ig)-like domain in neuregulins (NRGs). NRGs are signaling molecules which participate in cell-cell interactions in the nervous system, breast, heart, and other organ systems, and are implicated in the pathology of diseases including schizophrenia, multiple sclerosis, and breast cancer. There are four members of the neuregulin gene family (NRG-1, NRG-2, NRG-3, and NRG-4). The NRG-1 protein, binds to and activates the tyrosine kinases receptors ErbB3 and ErbB4, initiating signaling cascades. The other NRGs proteins bind one or the other or both of these ErbBs. NRG-1 has multiple functions: in the brain it regulates various processes such as radial glia formation and neuronal migration, dendritic development, and expression of neurotransmitters receptors, while in the peripheral nervous system NRG-1 regulates processes such as target cell differentiation, and Schwann cell survival. There are many NRG-1 isoforms which arise from the alternative splicing of mRNA. Less is known of the functions of the other NRGs. NRG-2 and NRG-3 are expressed predominantly in the nervous system. NRG-2 is expressed by motor neurons and terminal Schwann cells, and is concentrated near synaptic sites and may be a signal that regulates synaptic differentiation. NRG-4 has been shown to direct pancreatic islet cell development towards the delta-cell lineage.

Pssm-ID: 409408 [Multi-domain] Cd Length: 92 Bit Score: 53.67 E-value: 1.27e-08

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  249 SQMVLRGMDLLLECIASGV-PTPDIAWYKKGGDL---PSDKAKFENFNKA--LRITNVSEEDSGEYFCLASNKMGSIRHT 322
Cdd:cd05750      8 SQTVQEGSKLVLKCEATSEnPSPRYRWFKDGKELnrkRPKNIKIRNKKKNseLQINKAKLEDSGEYTCVVENILGKDTVT 87


                   ....*
gi 2217265369  323 ISVRV 327
Cdd:cd05750     88 GNVTV 92

Fourth Ig domain of the neural cell adhesion molecule contactin-2, and similar domains; The members here are composed of the fourth Ig domain of the neural cell adhesion molecule contactin-2. Contactins are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. Contactin-2 (also called TAG-1, axonin-1) facilitates cell adhesion by homophilic binding between molecules in apposed membranes. The first four Ig domains form the intermolecular binding fragment which arranges as a compact U-shaped module by contacts between Ig domains 1 and 4, and domains 2 and 3. It has been proposed that a linear zipper-like array forms, from contactin-2 molecules alternatively provided by the two apposed membranes.

Pssm-ID: 143205 [Multi-domain] Cd Length: 85 Bit Score: 53.37 E-value: 1.27e-08

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|..
gi 2217265369  438 LYNRTRLDCPFFGSPIPTLRWFKNGQGSNLDGGNYhvYENGSLEIKMIRKEDQGIYTCVATN 499
Cdd:cd05728     13 IGSSLRWECKASGNPRPAYRWLKNGQPLASENRIE--VEAGDLRITKLSLSDSGMYQCVAEN 72

Third immunoglobulin (Ig) domain of contactin; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the third immunoglobulin (Ig) domain of contactins. Contactins are neural cell adhesion molecules and are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. The first four Ig domains form the intermolecular binding fragment, which arranges as a compact U-shaped module via contacts between Ig domains 1 and 4, and between Ig domains 2 and 3. Contactin-2 (TAG-1, axonin-1) may play a part in the neuronal processes of neurite outgrowth, axon guidance and fasciculation, and neuronal migration. This group also includes contactin-1 and contactin-5. The different contactins show different expression patterns in the central nervous system. During development and in adulthood, contactin-2 is transiently expressed in subsets of central and peripheral neurons. Contactin-5 is expressed specifically in the rat postnatal nervous system, peaking at about 3 weeks postnatal, and a lack of contactin-5 (NB-2) results in an impairment of neuronal activity in the rat auditory system. Contactin-5 is highly expressed in the adult human brain in the occipital lobe and in the amygdala. Contactin-1 is differentially expressed in tumor tissues and may, through a RhoA mechanism, facilitate invasion and metastasis of human lung adenocarcinoma. This group belongs to the I-set of IgSF domains.

Pssm-ID: 409357 [Multi-domain] Cd Length: 88 Bit Score: 53.32 E-value: 1.31e-08

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 2217265369  253 LRGMDLLLECIASGVPTPDIAWYKKGGDLPSDKAKFENfNKALRITNVSEEDSGEYFCLASNKMG 317
Cdd:cd04968     14 LKGQTVTLECFALGNPVPQIKWRKVDGSPSSQWEITTS-EPVLEIPNVQFEDEGTYECEAENSRG 77

Immunoglobulin domain I1 of the titin I-band and similar proteins; a member of the I-set of IgSF domains; The members here are composed of the immunoglobulin domain I1 of the titin I-band and similar proteins. Titin is a key component in the assembly and functioning of vertebrate striated muscles. By providing connections at the level of individual microfilaments, it contributes to the fine balance of forces between the two halves of the sarcomere. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. The two sheets are linked together by a conserved disulfide bond between B strand and F strand. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. The Ig I1 domain of the titin I-band is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409543 [Multi-domain] Cd Length: 94 Bit Score: 53.58 E-value: 1.34e-08

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 2217265369  443 RLDCPFFGSPIPTLRWFKNGQ--GSNLDGGNYHVYENG---SLEIKMIRKEDQGIYTCVATNILGKAENQVRLEVK 513
Cdd:cd20951     19 KLRVEVQGKPDPEVKWYKNGVpiDPSSIPGKYKIESEYgvhVLHIRRVTVEDSAVYSAVAKNIHGEASSSASVVVE 94

Fibronectin type 3 domain; One of three types of internal repeats found in the plasma protein fibronectin. Its tenth fibronectin type III repeat contains an RGD cell recognition sequence in a flexible loop between 2 strands. Approximately 2% of all animal proteins contain the FN3 repeat; including extracellular and intracellular proteins, membrane spanning cytokine receptors, growth hormone receptors, tyrosine phosphatase receptors, and adhesion molecules. FN3-like domains are also found in bacterial glycosyl hydrolases.

Pssm-ID: 238020 [Multi-domain] Cd Length: 93 Bit Score: 53.27 E-value: 1.61e-08

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  822 APTEVKVRVMNSTAISLQWNRVYSDtvQGQLREYRAYYWRESSllknlwvSQKRQQASFPGDRLRGVVSRLFPYSNYKLE 901
Cdd:cd00063      3 PPTNLRVTDVTSTSVTLSWTPPEDD--GGPITGYVVEYREKGS-------GDWKEVEVTPGSETSYTLTGLKPGTEYEFR 73

                           90       100
                   ....*....|....*....|
gi 2217265369  902 MVVVNGRGDGPRSETKEFTT 921
Cdd:cd00063     74 VRAVNGGGESPPSESVTVTT 93

First immunoglobulin (Ig) domain of contactin; member of the I-set of (Ig) superfamily domains; The members here are composed of the first immunoglobulin (Ig) domain of contactins. Contactins are neural cell adhesion molecules and are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. The first four Ig domains form the intermolecular binding fragment, which arranges as a compact U-shaped module via contacts between Ig domains 1 and 4, and between Ig domains 2 and 3. Contactin-2 (TAG-1, axonin-1) may play a part in the neuronal processes of neurite outgrowth, axon guidance and fasciculation, and neuronal migration. This group also includes contactin-1 and contactin-5. The different contactins show different expression patterns in the central nervous system. During development and in adulthood, contactin-2 is transiently expressed in subsets of central and peripheral neurons. Contactin-5 is expressed specifically in the rat postnatal nervous system, peaking at about 3 weeks postnatal, and a lack of contactin-5 (NB-2) results in an impairment of neuronal activity in the rat auditory system. Contactin-5 is highly expressed in the adult human brain in the occipital lobe and in the amygdala. Contactin-1 is differentially expressed in tumor tissues and may, through a RhoA mechanism, facilitate invasion and metastasis of human lung adenocarcinoma. This group belongs to the I-set of IgSF domains.

Pssm-ID: 409356 [Multi-domain] Cd Length: 96 Bit Score: 53.40 E-value: 1.72e-08

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369   44 DHIVDPRDN----ILIECEAKGNPAPSFHWTRNSRFFNIAKDPRVSMrrRSGTLVIDfrsggRPEEYE--GEYQCFARNK 117
Cdd:cd04967      9 DDTIFPEDSdekkVALNCRARANPVPSYRWLMNGTEIDLESDYRYSL--VDGTLVIS-----NPSKAKdaGHYQCLATNT 81

                           90
                   ....*....|..
gi 2217265369  118 FGTALSNRIRLQ 129
Cdd:cd04967     82 VGSVLSREATLQ 93

Immunoglobulin domain; This domain contains immunoglobulin-like domains.

Pssm-ID: 464026 [Multi-domain] Cd Length: 79 Bit Score: 52.78 E-value: 1.73e-08

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  243 PQGTASSQMVLRGMDLLLECIASGVPTPDIAWYKKGGDLPSDKAKFenfnkalrITNVSEEDSGEYFCLASNKMGSIR-- 320
Cdd:pfam13895    2 PVLTPSPTVVTEGEPVTLTCSAPGNPPPSYTWYKDGSAISSSPNFF--------TLSVSAEDSGTYTCVARNGRGGKVsn 73


                   ....*.
gi 2217265369  321 -HTISV 325
Cdd:pfam13895   74 pVELTV 79

Fibronectin type 3 domain; One of three types of internal repeats found in the plasma protein fibronectin. Its tenth fibronectin type III repeat contains an RGD cell recognition sequence in a flexible loop between 2 strands. Approximately 2% of all animal proteins contain the FN3 repeat; including extracellular and intracellular proteins, membrane spanning cytokine receptors, growth hormone receptors, tyrosine phosphatase receptors, and adhesion molecules. FN3-like domains are also found in bacterial glycosyl hydrolases.

Pssm-ID: 238020 [Multi-domain] Cd Length: 93 Bit Score: 52.88 E-value: 2.10e-08

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  723 SNPGDVKGEGTRKNNMEITWTPmnATSAFGPNLRYIVKWRRRETREaWNNVTVWGS---RYVVGQTPVYVPYEIRVQAEN 799
Cdd:cd00063      2 SPPTNLRVTDVTSTSVTLSWTP--PEDDGGPITGYVVEYREKGSGD-WKEVEVTPGsetSYTLTGLKPGTEYEFRVRAVN 78

                           90
                   ....*....|....
gi 2217265369  800 DFGKGPEPESVIGY 813
Cdd:cd00063     79 GGGESPPSESVTVT 92

immunoglobulin-like domain of telokin and similar proteins; a member of the I-set of IgSF domains; The members here are composed of the immunoglobulin (Ig) domain in telokin, the C-terminal domain of myosin light chain kinase which is identical to telokin, and similar proteins. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structure of the telokin Ig domain lacks this strand and thus it belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409565 [Multi-domain] Cd Length: 88 Bit Score: 52.58 E-value: 2.31e-08

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  524 DQVARRGTTVQLECRVKHDPSLKltVSWLKDDEPLYIGNRMKKEDD-----SLTIFGVAERDQGSYTCVASTELDQDLAK 598
Cdd:cd20973      6 DKEVVEGSAARFDCKVEGYPDPE--VKWMKDDNPIVESRRFQIDQDedglcSLIISDVCGDDSGKYTCKAVNSLGEATCS 83


                   ....*
gi 2217265369  599 AYLTV 603
Cdd:cd20973     84 AELTV 88

Immunoglobulin (Ig)-like domain of myotilin, palladin, and myopalladin; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the immunoglobulin (Ig)-like domain in myotilin, palladin, and myopalladin. Myotilin, palladin, and myopalladin function as scaffolds that regulate actin organization. Myotilin and myopalladin are most abundant in skeletal and cardiac muscle; palladin is ubiquitously expressed in the organs of developing vertebrates and plays a key role in cellular morphogenesis. The three family members each interact with specific molecular partners with all three binding to alpha-actinin; In addition, palladin also binds to vasodilator-stimulated phosphoprotein (VASP) and ezrin, myotilin binds to filamin and actin, and myopalladin also binds to nebulin and cardiac ankyrin repeat protein (CARP). This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409405 [Multi-domain] Cd Length: 91 Bit Score: 52.88 E-value: 2.35e-08

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 2217265369  442 TRLDCPFFGSPIPTLRWFKNGQGSNLDGGN-YHVYENG--SLEIKMIRKEDQGIYTCVATNILGKAENQVRLEV 512
Cdd:cd05744     18 CRFDCKVSGLPTPDLFWQLNGKPVRPDSAHkMLVRENGrhSLIIEPVTKRDAGIYTCIARNRAGENSFNAELVV 91

Second immunoglobulin (Ig)-like domain of fibroblast growth factor (FGF) receptor; member of the I-set of IgSF domains; The members here are composed of the second immunoglobulin (Ig)-like domain of fibroblast growth factor (FGF) receptor. FGF receptors bind FGF signaling polypeptides. FGFs participate in multiple processes such as morphogenesis, development, and angiogenesis. FGFs bind to four FGF receptor tyrosine kinases (FGFR1, FGFR2, FGFR3, FGFR4). Receptor diversity is controlled by alternative splicing producing splice variants with different ligand binding characteristics and different expression patterns. FGFRs have an extracellular region comprised of three IG-like domains, a single transmembrane helix, and an intracellular tyrosine kinase domain. Ligand binding and specificity reside in the Ig-like domains 2 and 3, and the linker region that connects these two. FGFR activation and signaling depend on FGF-induced dimerization, a process involving cell surface heparin or heparin sulfate proteoglycans.

Pssm-ID: 409443 [Multi-domain] Cd Length: 95 Bit Score: 52.55 E-value: 2.83e-08

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 2217265369  260 LECIASGVPTPDIAWYKKGGDLPSDKA----KFENFNKALRITNVSEEDSGEYFCLASNKMGSIRHTISVRV 327
Cdd:cd05857     24 FRCPAAGNPTPTMRWLKNGKEFKQEHRiggyKVRNQHWSLIMESVVPSDKGNYTCVVENEYGSINHTYHLDV 95

Immunoglobulin domain; The members here are composed of the immunoglobulin (Ig) domain found in the Ig superfamily. The Ig superfamily is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. Members of this group are components of immunoglobulin, neuroglia, cell surface glycoproteins, including T-cell receptors, CD2, CD4, CD8, and membrane glycoproteins, including butyrophilin and chondroitin sulfate proteoglycan core protein. A predominant feature of most Ig domains is a disulfide bridge connecting the two beta-sheets with a tryptophan residue packed against the disulfide bond. Ig superfamily (IgSF) domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Typically, the V-set domains have A, B, E, and D strands in one sheet and A', G, F, C, C' and C" in the other. The structures in C1-set are smaller than those in the V-set; they have one beta sheet that is formed by strands A, B, E, and D and the other by strands G, F, C, and C'. Moreover, a C1-set Ig domain contains a short C' strand (three residues) and lacks A' and C" strand. Unlike other Ig domain sets, C2-set structures do not have a D strand. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409353 [Multi-domain] Cd Length: 70 Bit Score: 51.18 E-value: 4.71e-08

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 2217265369   55 IECEAKGNPAPSFHWTRNSRFFNIAKDPRVSMRRRSGTLVIDfrsgGRPEEYEGEYQCFARNKFGTALS 123
Cdd:cd00096      3 LTCSASGNPPPTITWYKNGKPLPPSSRDSRRSELGNGTLTIS----NVTLEDSGTYTCVASNSAGGSAS 67

Fifth immunoglobulin (Ig) domain of contactin-1; The members here are composed of the fifth immunoglobulin (Ig) domain of the neural cell adhesion molecule contactin-1. Contactins are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. Contactin-1 is differentially expressed in tumor tissues and may through a RhoA mechanism, facilitate invasion and metastasis of human lung adenocarcinoma.

Pssm-ID: 409438 Cd Length: 89 Bit Score: 51.92 E-value: 5.06e-08

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  423 PPRMLSPRNQLIRVILYNRTRLDCPFFGSPIPTLRWFKnGQGSNLDGGNYHVYENGSLEIKMIRKEDQGIYTCVATNILG 502
Cdd:cd05852      1 PTFEFNPMKKKILAAKGGRVIIECKPKAAPKPKFSWSK-GTELLVNNSRISIWDDGSLEILNITKLDEGSYTCFAENNRG 79

                           90
                   ....*....|
gi 2217265369  503 KAENQVRLEV 512
Cdd:cd05852     80 KANSTGVLSV 89

First immunoglobulin (Ig) domain of contactin-2; member of the I-set of Ig superfamily domains; The members here are composed of the first immunoglobulin (Ig) domain of the neural cell adhesion molecule contactin-2-like. Contactins are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. Contactin-2 (TAG-1, axonin-1) facilitates cell adhesion by homophilic binding between molecules in apposed membranes. It may play a part in the neuronal processes of neurite outgrowth, axon guidance and fasciculation, and neuronal migration. The first four Ig domains form the intermolecular binding fragment, which arranges as a compact U-shaped module by contacts between IG domains 1 and 4, and domains 2 and 3. The different contactins show different expression patterns in the central nervous system. During development and in adulthood, contactin-2 is transiently expressed in subsets of central and peripheral neurons. Contactin-2 is also expressed in retinal amacrine cells in the developing chick retina, corresponding to the period of formation and maturation of AC processes. This group belongs to the I-set of IgSF domains.

Pssm-ID: 409437 [Multi-domain] Cd Length: 97 Bit Score: 51.85 E-value: 5.10e-08

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  331 PYWLDEPKNLILAPG---EDGRLVCRANGNPKPTVQWMVNGEPLQSAPPNPNREVAGDTIIFRDTQISSRAVYQCNTSNE 407
Cdd:cd05850      3 PVFEEQPSSTLFPEGsaeEKVTLACRARASPPATYRWKMNGTELKMEPDSRYRLVAGNLVISNPVKAKDAGSYQCLASNR 82


                   ..
gi 2217265369  408 HG 409
Cdd:cd05850     83 RG 84

Third immunoglobulin (Ig) domain of contactin; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the third immunoglobulin (Ig) domain of contactins. Contactins are neural cell adhesion molecules and are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. The first four Ig domains form the intermolecular binding fragment, which arranges as a compact U-shaped module via contacts between Ig domains 1 and 4, and between Ig domains 2 and 3. Contactin-2 (TAG-1, axonin-1) may play a part in the neuronal processes of neurite outgrowth, axon guidance and fasciculation, and neuronal migration. This group also includes contactin-1 and contactin-5. The different contactins show different expression patterns in the central nervous system. During development and in adulthood, contactin-2 is transiently expressed in subsets of central and peripheral neurons. Contactin-5 is expressed specifically in the rat postnatal nervous system, peaking at about 3 weeks postnatal, and a lack of contactin-5 (NB-2) results in an impairment of neuronal activity in the rat auditory system. Contactin-5 is highly expressed in the adult human brain in the occipital lobe and in the amygdala. Contactin-1 is differentially expressed in tumor tissues and may, through a RhoA mechanism, facilitate invasion and metastasis of human lung adenocarcinoma. This group belongs to the I-set of IgSF domains.

Pssm-ID: 409357 [Multi-domain] Cd Length: 88 Bit Score: 51.39 E-value: 5.95e-08

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 2217265369  444 LDCPFFGSPIPTLRWFKngqgsnLDGGNYHVYE----NGSLEIKMIRKEDQGIYTCVATNILGKAENQVRLEV 512
Cdd:cd04968     21 LECFALGNPVPQIKWRK------VDGSPSSQWEittsEPVLEIPNVQFEDEGTYECEAENSRGKDTVQGRIIV 87

Fibronectin type 3 domain; One of three types of internal repeat within the plasma protein, fibronectin. The tenth fibronectin type III repeat contains a RGD cell recognition sequence in a flexible loop between 2 strands. Type III modules are present in both extracellular and intracellular proteins.

Pssm-ID: 214495 [Multi-domain] Cd Length: 83 Bit Score: 51.46 E-value: 6.11e-08

                            10        20        30        40        50        60        70        80
                    ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369   723 SNPGDVKGEGTRKNNMEITWTPMNATSAFGPNLRYIVKWrrRETREAWNNVTVWGS--RYVVGQTPVYVPYEIRVQAEND 800
Cdd:smart00060    2 SPPSNLRVTDVTSTSVTLSWEPPPDDGITGYIVGYRVEY--REEGSEWKEVNVTPSstSYTLTGLKPGTEYEFRVRAVNG 79


                    ....
gi 2217265369   801 FGKG 804
Cdd:smart00060   80 AGEG 83

Second immunoglobulin (Ig)-like domain of fibroblast growth factor (FGF) receptor; member of the I-set of IgSF domains; The members here are composed of the second immunoglobulin (Ig)-like domain of fibroblast growth factor (FGF) receptor. FGF receptors bind FGF signaling polypeptides. FGFs participate in multiple processes such as morphogenesis, development, and angiogenesis. FGFs bind to four FGF receptor tyrosine kinases (FGFR1, FGFR2, FGFR3, FGFR4). Receptor diversity is controlled by alternative splicing producing splice variants with different ligand binding characteristics and different expression patterns. FGFRs have an extracellular region comprised of three IG-like domains, a single transmembrane helix, and an intracellular tyrosine kinase domain. Ligand binding and specificity reside in the Ig-like domains 2 and 3, and the linker region that connects these two. FGFR activation and signaling depend on FGF-induced dimerization, a process involving cell surface heparin or heparin sulfate proteoglycans.

Pssm-ID: 409443 [Multi-domain] Cd Length: 95 Bit Score: 51.78 E-value: 6.36e-08

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 2217265369  440 NRTRLDCPFFGSPIPTLRWFKNGQGSNLDG--GNYHV-YENGSLEIKMIRKEDQGIYTCVATNILGKAENQVRLEV 512
Cdd:cd05857     20 NTVKFRCPAAGNPTPTMRWLKNGKEFKQEHriGGYKVrNQHWSLIMESVVPSDKGNYTCVVENEYGSINHTYHLDV 95

Immunoglobulin like; IG domains that cannot be classified into one of IGv1, IGc1, IGc2, IG.

Pssm-ID: 214653 [Multi-domain] Cd Length: 85 Bit Score: 51.35 E-value: 6.49e-08

                            10        20        30        40        50        60        70        80
                    ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369   337 PKNLILAPGEDGRLVCRANGNPKPTVQWMVNGEPLQSAPPNPNREVAGD--TIIFRDTQISSRAVYQCNTSNEHGYLLAN 414
Cdd:smart00410    1 PPSVTVKEGESVTLSCEASGSPPPEVTWYKQGGKLLAESGRFSVSRSGStsTLTISNVTPEDSGTYTCAATNSSGSASSG 80


                    ....*
gi 2217265369   415 AFVSV 419
Cdd:smart00410   81 TTLTV 85

Fibronectin type 3 domain [General function prediction only];

Pssm-ID: 442628 [Multi-domain] Cd Length: 603 Bit Score: 56.93 E-value: 7.91e-08

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  766 TREAWNNVTVWGSRYVVGQTPVYVP---YEIRVQAENDFGKGPEPESVIGYSGEDYPrAAPTEVKVRVMNSTAISLQWNR 842
Cdd:COG3401    177 TAAVATTSLTVTSTTLVDGGGDIEPgttYYYRVAATDTGGESAPSNEVSVTTPTTPP-SAPTGLTATADTPGSVTLSWDP 255

                           90       100       110       120       130       140       150       160
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  843 VYSDTVQGqlreYRAYYWRESSllkNLWVS-QKRQQASFpgdrlrgVVSRLFPYSNYKLEMVVVNGRGD-GPRSETKEFT 920
Cdd:COG3401    256 VTESDATG----YRVYRSNSGD---GPFTKvATVTTTSY-------TDTGLTNGTTYYYRVTAVDAAGNeSAPSNVVSVT 321

                          170       180       190       200       210       220       230       240
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  921 TPEGVPSAPRRFRVRQPNLETINLEWDHPehPNGIMIGYTLKYVAFNGTKVGKqIVEnfSPNQTKFTVQRTDPVSRYRFT 1000
Cdd:COG3401    322 TDLTPPAAPSGLTATAVGSSSITLSWTAS--SDADVTGYNVYRSTSGGGTYTK-IAE--TVTTTSYTDTGLTPGTTYYYK 396

                          250       260       270       280       290
                   ....*....|....*....|....*....|....*....|....*....|.
gi 2217265369 1001 LSARTQVG-----SGEAVTEESPAPPNEATPTAAPPTLPPTTVGATGAVSS 1046
Cdd:COG3401    397 VTAVDAAGnesapSEEVSATTASAASGESLTASVDAVPLTDVAGATAAASA 447

Fifth immunoglobulin (Ig) domain of contactin; The members here are composed of the fifth immunoglobulin (Ig) domain of contactins. Contactins are neural cell adhesion molecules and are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. The first four Ig domains form the intermolecular binding fragment, which arranges as a compact U-shaped module via contacts between Ig domains 1 and 4, and between Ig domains 2 and 3. Contactin-2 (TAG-1, axonin-1) may play a part in the neuronal processes of neurite outgrowth, axon guidance and fasciculation, and neuronal migration. This group also includes contactin-1 and contactin-5. The different contactins show different expression patterns in the central nervous system. During development and in adulthood, contactin-2 is transiently expressed in subsets of central and peripheral neurons. Contactin-5 is expressed specifically in the rat postnatal nervous system, peaking at about 3 weeks postnatal, and a lack of contactin-5 (NB-2) results in an impairment of neuronal activity in the rat auditory system. Contactin-5 is highly expressed in the adult human brain in the occipital lobe and in the amygdala. Contactin-1 is differentially expressed in tumor tissues and may, through a RhoA mechanism, facilitate invasion and metastasis of human lung adenocarcinoma.

Pssm-ID: 409358 [Multi-domain] Cd Length: 89 Bit Score: 51.31 E-value: 8.05e-08

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369   35 PTITKQSAKDHIVDPRD-NILIECEAKGNPAPSFHWTRNSRffNIAKDPRVSMrRRSGTLVIdfRSGGRPEeyEGEYQCF 113
Cdd:cd04969      1 PDFELNPVKKKILAAKGgDVIIECKPKASPKPTISWSKGTE--LLTNSSRICI-LPDGSLKI--KNVTKSD--EGKYTCF 73

                           90
                   ....*....|
gi 2217265369  114 ARNKFGTALS 123
Cdd:cd04969     74 AVNFFGKANS 83

Third immunoglobulin domain of the Drosophila melanogaster Dscam protein, and similar domains; a member of the Constant 2 (C2)-set of IgSF domains; The members here are composed of the third immunoglobulin domain of the Drosophila melanogaster Down syndrome cell adhesion molecule (DSCAM) protein and similar proteins. Down syndrome cell adhesion molecule (DSCAM) is a cell adhesion molecule that plays critical roles in neural development, including axon guidance and branching, axon target recognition, self-avoidance and synaptic formation. DSCAM belongs to the immunoglobulin superfamily and contributes to defects in the central nervous system in Down syndrome patients. Vertebrate DSCAMs differ from Drosophila Dscam1 in that they lack the extensive alternative splicing that occurs in the insect gene. Drosophila melanogaster Dscam has 38,016 isoforms generated by the alternative splicing of four variable exon clusters, which allows every neuron in the fly to display a distinctive set of Dscam proteins on its cell surface. Drosophila Dscam1 is a cell-surface protein that plays important roles in neural development and axon tiling of neurons. It is shown that thousands of isoforms bind themselves through specific homophilic (self-binding) interactions, a process which mediates cellular self-recognition. Drosophila Dscam2 is also alternatively spliced and plays a key role in the development of two visual system neurons, monopolar cells L1 and L2. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. This group belongs to the C2-set of IgSF domains, having A, B, and E strands in one beta-sheet and A', G, F, C, and C' in the other. Unlike other Ig domain sets, the C2-set lacks the D strand.

Pssm-ID: 409549 [Multi-domain] Cd Length: 88 Bit Score: 50.99 E-value: 8.63e-08

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 2217265369  250 QMVLRGMDLLLECIASGVPTPDIAWYKKGGDLPSDKAKFENFNKALRITNVSEEDSGEYFCLASNKMGSIRHTISVRV 327
Cdd:cd20957     11 QTVDFGRTAVFNCSVTGNPIHTVLWMKDGKPLGHSSRVQILSEDVLVIPSVKREDKGMYQCFVRNDGDSAQATAELKL 88

Immunoglobulin like; IG domains that cannot be classified into one of IGv1, IGc1, IGc2, IG.

Pssm-ID: 214653 [Multi-domain] Cd Length: 85 Bit Score: 50.97 E-value: 9.41e-08

                            10        20        30        40        50        60        70        80
                    ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369    43 KDHIVDPRDNILIECEAKGNPAPSFHWTRNSRFFnIAKDPRVSMRRRSGTLVIDFRSGGRpeEYEGEYQCFARNKFGTAL 122
Cdd:smart00410    2 PSVTVKEGESVTLSCEASGSPPPEVTWYKQGGKL-LAESGRFSVSRSGSTSTLTISNVTP--EDSGTYTCAATNSSGSAS 78


                    ....*...
gi 2217265369   123 SNrIRLQV 130
Cdd:smart00410   79 SG-TTLTV 85

Immunoglobulin like; IG domains that cannot be classified into one of IGv1, IGc1, IGc2, IG.

Pssm-ID: 214653 [Multi-domain] Cd Length: 85 Bit Score: 50.58 E-value: 9.98e-08

                            10        20        30        40        50        60        70        80
                    ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369   143 PVVVQEGAPLTLQCnPPPGLPSPVIFWMSSSMEPITQDKRVS---QGHNGDLYFSNVMLQDmQTDYSCNARfhfTHTIQQ 219
Cdd:smart00410    3 SVTVKEGESVTLSC-EASGSPPPEVTWYKQGGKLLAESGRFSvsrSGSTSTLTISNVTPED-SGTYTCAAT---NSSGSA 77


                    ....*...
gi 2217265369   220 KNPFTLKV 227
Cdd:smart00410   78 SSGTTLTV 85

Second immunoglobulin (Ig)-like domain of a Follistatin-related protein 5, and similar domains; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the second immunoglobulin (Ig)-like domain found in human Follistatin-related protein 5 (FSTL5) and a follistatin-like molecule encoded by the CNS-related Mahya gene. Mahya genes have been retained in certain Bilaterian branches during evolution. They are conserved in Hymenoptera and Deuterostomes, but are absent from other metazoan species such as fruit fly and nematode. Mahya proteins are secretory, with a follistatin-like domain (Kazal-type serine/threonine protease inhibitor domain and EF-hand calcium-binding domain), two Ig-like domains, and a novel C-terminal domain. Mahya may be involved in learning and memory and in processing of sensory information in Hymenoptera and vertebrates. Follistatin is a secreted, multidomain protein that binds activins with high affinity and antagonizes their signaling.

Pssm-ID: 409399 [Multi-domain] Cd Length: 93 Bit Score: 51.11 E-value: 1.06e-07

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 2217265369  444 LDCPFFGSPIPTLRWFKNGQGSNLD-GGNYHVYENGS-LEIKMIRKEDQGIYTCVATNILGKAENQVRLEVKD 514
Cdd:cd05736     20 LRCHAEGIPLPRVQWLKNGMDINPKlSKQLTLIANGSeLHISNVRYEDTGAYTCIAKNEGGVDEDISSLFVED 92

Fourth Ig-like domain from smooth muscle myosin light chain kinase and similar domains ; a member of the I-set of IgSF domains; The members here are composed of the fourth immunoglobulin (Ig)-like domain from smooth muscle myosin light chain kinase (MYLK) and similar domains. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structure of this group shows that the fourth Ig-like domain from myosin light chain kinase lacks this strand and thus belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409568 [Multi-domain] Cd Length: 90 Bit Score: 50.71 E-value: 1.16e-07

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  444 LDCPFFGSPIPTLRWFKNGQGSNLDGGNYHV-YENGSLEIKMIRKEDQGIYTCVATNILGKAENQVRLEV 512
Cdd:cd20976     21 AQCSARGKPVPRITWIRNAQPLQYAADRSTCeAGVGELHIQDVLPEDHGTYTCLAKNAAGQVSCSAWVTV 90

agrin-responsive second immunoglobulin-like domains (Ig2) of the Muscle-specific kinase (MuSK) ectodomain; a member of the I-set of Ig superfamily domains; The members here are composed of the second immunoglobulin-like (Ig) domains of the Muscle-specific kinase (MuSK) ectodomain. MuSK is a receptor tyrosine kinase specifically expressed in skeletal muscle, where it plays a central role in the formation and maintenance of the neuromuscular junction (NMJ). MuSK is activated by agrin, a neuron-derived heparan sulfate proteoglycan. The activation of MUSK in myotubes regulates the formation of NMJs through the regulation of different processes including the specific expression of genes in subsynaptic nuclei, the reorganization of the actin cytoskeleton and the clustering of the acetylcholine receptors (AChR) in the postsynaptic membrane. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structure of the MuSK lacks this strand and thus it belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409560 [Multi-domain] Cd Length: 88 Bit Score: 50.70 E-value: 1.25e-07

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  434 IRVILYNRTRLDCPFFGSPIPTLRWFKnGQGSNLDGGNYHVYENGSLEIKMIRKEDQGIYTCVATNILGKAENQ-VRLEV 512
Cdd:cd20968      9 VTIIEGLKAVLPCTTMGNPKPSVSWIK-GDDLIKENNRIAVLESGSLRIHNVQKEDAGQYRCVAKNSLGIAYSKpVTIEV 87


                   .
gi 2217265369  513 K 513
Cdd:cd20968     88 E 88

agrin-responsive first immunoglobulin-like domains (Ig1) of the MuSK ectodomain; a member of the I-set of IgSF domains; The members here are composed of the first immunoglobulin-like domains (Ig1) of the Muscle-specific kinase (MuSK). MuSK is a receptor tyrosine kinase specifically expressed in skeletal muscle, where it plays a central role in the formation and maintenance of the neuromuscular junction (NMJ). MuSK is activated by agrin, a neuron-derived heparan sulfate proteoglycan. The activation of MUSK in myotubes regulates the formation of NMJs through the regulation of different processes including the specific expression of genes in subsynaptic nuclei, the reorganization of the actin cytoskeleton and the clustering of the acetylcholine receptors (AChR) in the postsynaptic membrane. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structure of the MuSK lacks this strand and thus it belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409562 [Multi-domain] Cd Length: 92 Bit Score: 50.58 E-value: 1.27e-07

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369   38 TKQSAKDHIVDPRDNILIECEAKGNPAPSFHWTRNSRFFnIAKDPRVSMRRRSGTLVIdfRSGGRPEeyEGEYQCFARNK 117
Cdd:cd20970      5 TPQPSFTVTAREGENATFMCRAEGSPEPEISWTRNGNLI-IEFNTRYIVRENGTTLTI--RNIRRSD--MGIYLCIASNG 79

                           90
                   ....*....|...
gi 2217265369  118 FGTALSNRIRLQV 130
Cdd:cd20970     80 VPGSVEKRITLQV 92

agrin-responsive second immunoglobulin-like domains (Ig2) of the Muscle-specific kinase (MuSK) ectodomain; a member of the I-set of Ig superfamily domains; The members here are composed of the second immunoglobulin-like (Ig) domains of the Muscle-specific kinase (MuSK) ectodomain. MuSK is a receptor tyrosine kinase specifically expressed in skeletal muscle, where it plays a central role in the formation and maintenance of the neuromuscular junction (NMJ). MuSK is activated by agrin, a neuron-derived heparan sulfate proteoglycan. The activation of MUSK in myotubes regulates the formation of NMJs through the regulation of different processes including the specific expression of genes in subsynaptic nuclei, the reorganization of the actin cytoskeleton and the clustering of the acetylcholine receptors (AChR) in the postsynaptic membrane. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structure of the MuSK lacks this strand and thus it belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409560 [Multi-domain] Cd Length: 88 Bit Score: 50.70 E-value: 1.29e-07

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 2217265369  252 VLRGMDLLLECIASGVPTPDIAWYKkGGDLPSDKAKFENFNK-ALRITNVSEEDSGEYFCLASNKMGS 318
Cdd:cd20968     11 IIEGLKAVLPCTTMGNPKPSVSWIK-GDDLIKENNRIAVLESgSLRIHNVQKEDAGQYRCVAKNSLGI 77

First immunoglobulin (Ig) domain of contactin; member of the I-set of (Ig) superfamily domains; The members here are composed of the first immunoglobulin (Ig) domain of contactins. Contactins are neural cell adhesion molecules and are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. The first four Ig domains form the intermolecular binding fragment, which arranges as a compact U-shaped module via contacts between Ig domains 1 and 4, and between Ig domains 2 and 3. Contactin-2 (TAG-1, axonin-1) may play a part in the neuronal processes of neurite outgrowth, axon guidance and fasciculation, and neuronal migration. This group also includes contactin-1 and contactin-5. The different contactins show different expression patterns in the central nervous system. During development and in adulthood, contactin-2 is transiently expressed in subsets of central and peripheral neurons. Contactin-5 is expressed specifically in the rat postnatal nervous system, peaking at about 3 weeks postnatal, and a lack of contactin-5 (NB-2) results in an impairment of neuronal activity in the rat auditory system. Contactin-5 is highly expressed in the adult human brain in the occipital lobe and in the amygdala. Contactin-1 is differentially expressed in tumor tissues and may, through a RhoA mechanism, facilitate invasion and metastasis of human lung adenocarcinoma. This group belongs to the I-set of IgSF domains.

Pssm-ID: 409356 [Multi-domain] Cd Length: 96 Bit Score: 50.70 E-value: 1.40e-07

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  331 PYWLDEPKNLILAPGEDGR---LVCRANGNPKPTVQWMVNGEPLQSAPPNPNREVAGDTIIFRDTQISSRAVYQCNTSNE 407
Cdd:cd04967      2 PVFEEQPDDTIFPEDSDEKkvaLNCRARANPVPSYRWLMNGTEIDLESDYRYSLVDGTLVISNPSKAKDAGHYQCLATNT 81


                   ....*.
gi 2217265369  408 HGYLLA 413
Cdd:cd04967     82 VGSVLS 87

Immunoglobulin domain I1 of the titin I-band and similar proteins; a member of the I-set of IgSF domains; The members here are composed of the immunoglobulin domain I1 of the titin I-band and similar proteins. Titin is a key component in the assembly and functioning of vertebrate striated muscles. By providing connections at the level of individual microfilaments, it contributes to the fine balance of forces between the two halves of the sarcomere. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. The two sheets are linked together by a conserved disulfide bond between B strand and F strand. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. The Ig I1 domain of the titin I-band is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409543 [Multi-domain] Cd Length: 94 Bit Score: 50.50 E-value: 1.43e-07

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  249 SQMVLRGMDLLLECIASGVPTPDIAWYKKG----GDLPSDKAKFENFN--KALRITNVSEEDSGEYFCLASNKMGSIRHT 322
Cdd:cd20951      9 SHTVWEKSDAKLRVEVQGKPDPEVKWYKNGvpidPSSIPGKYKIESEYgvHVLHIRRVTVEDSAVYSAVAKNIHGEASSS 88


                   ....*.
gi 2217265369  323 ISVRVK 328
Cdd:cd20951     89 ASVVVE 94

Second immunoglobulin (Ig)-like domain of a Follistatin-related protein 5, and similar domains; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the second immunoglobulin (Ig)-like domain found in human Follistatin-related protein 5 (FSTL5) and a follistatin-like molecule encoded by the CNS-related Mahya gene. Mahya genes have been retained in certain Bilaterian branches during evolution. They are conserved in Hymenoptera and Deuterostomes, but are absent from other metazoan species such as fruit fly and nematode. Mahya proteins are secretory, with a follistatin-like domain (Kazal-type serine/threonine protease inhibitor domain and EF-hand calcium-binding domain), two Ig-like domains, and a novel C-terminal domain. Mahya may be involved in learning and memory and in processing of sensory information in Hymenoptera and vertebrates. Follistatin is a secreted, multidomain protein that binds activins with high affinity and antagonizes their signaling.

Pssm-ID: 409399 [Multi-domain] Cd Length: 93 Bit Score: 49.95 E-value: 2.41e-07

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 2217265369  260 LECIASGVPTPDIAWYKKGGDLP---SDKAKFENFNKALRITNVSEEDSGEYFCLASNKMGSIRHTISVRVK 328
Cdd:cd05736     20 LRCHAEGIPLPRVQWLKNGMDINpklSKQLTLIANGSELHISNVRYEDTGAYTCIAKNEGGVDEDISSLFVE 91

Fourth immunoglobulin (Ig)-like domain in Robo (roundabout) receptors; member of the I-set of Ig superfamily (IgSF) domains; Members here are composed the fourth immunoglobulin (Ig)-like domain in Robo (roundabout) receptors. Robo receptors play a role in the development of the central nervous system (CNS), and are receptors of Slit protein. Slit is a repellant secreted by the neural cells in the midline. Slit acts through Robo to prevent most neurons from crossing the midline from either side. Three mammalian Robo homologs (Robo1, Robo2, Robo3), and three mammalian Slit homologs (Slit-1, Slit-2, Slit-3), have been identified. Commissural axons, which cross the midline, express low levels of Robo; longitudinal axons, which avoid the midline, express high levels of Robo. Robo1, Robo2, and Robo3 are expressed by commissural neurons in the vertebrate spinal cord and Slit-1, Slit-2, and Slit-3 are expressed at the ventral midline. Robo-3 is a divergent member of the Robo family which instead of being a positive regulator of Slit responsiveness, antagonizes Slit responsiveness in precrossing axons. The Slit-Robo interaction is mediated by the second leucine-rich repeat (LRR) domain of Slit and the two N-terminal Ig domains of Robo, Ig1 and Ig2. The primary Robo binding site for Slit2 has been shown by surface plasmon resonance experiments and mutational analysis to be the Ig1 domain, while the Ig2 domain has been proposed to harbor a weak secondary binding site. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409391 [Multi-domain] Cd Length: 98 Bit Score: 49.95 E-value: 2.61e-07

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  336 EPKNLILAPGEDGRLVCRANGNPKPTVQWMVNGE-----PLQSAPPNPNREVA--GDTIIfRDTQISSRAVYQCNTSNEH 408
Cdd:cd05726      5 KPRDQVVALGRTVTFQCETKGNPQPAIFWQKEGSqnllfPYQPPQPSSRFSVSptGDLTI-TNVQRSDVGYYICQALNVA 83

                           90
                   ....*....|....
gi 2217265369  409 GYLLANAFVSVLDV 422
Cdd:cd05726     84 GSILAKAQLEVTDV 97

Fourth immunoglobulin (Ig)-like domain of hemolin, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the fourth immunoglobulin (Ig)-like domain of hemolin and similar proteins. Hemolin, an insect immunoglobulin superfamily (IgSF) member containing four Ig-like domains, is a lipopolysaccharide-binding immune protein induced during bacterial infection. Hemolin shares significant sequence similarity with the first four Ig-like domains of the transmembrane cell adhesion molecules (CAMs) of the L1 family. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. The fourth Ig-like domain of hemolin is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set domains, members of the I-set have a discontinuous A strand but lack a C" strand. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409570 [Multi-domain] Cd Length: 88 Bit Score: 49.31 E-value: 3.01e-07

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  522 PEDQVARRGT-TVQLECRVKHDPSLKltVSWLKDDEPLyIGN--RMKKEDDSLTIFGVAERDQGSYTCVASTELDQDLAK 598
Cdd:cd20978      7 PEKNVVVKGGqDVTLPCQVTGVPQPK--ITWLHNGKPL-QGPmeRATVEDGTLTIINVQPEDTGYYGCVATNEIGDIYTE 83


                   ....*
gi 2217265369  599 AYLTV 603
Cdd:cd20978     84 TLLHV 88

First immunoglobulin (Ig)-like domain of fibroblast growth factor receptor (FGFR); member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the first immunoglobulin (Ig)-like domain of fibroblast growth factor receptor (FGFR). Fibroblast growth factors (FGFs) participate in morphogenesis, development, angiogenesis, and wound healing. These FGF-stimulated processes are mediated by four FGFR tyrosine kinases (FGRF1-4). FGFRs are comprised of an extracellular portion consisting of three Ig-like domains, a transmembrane helix, and a cytoplasmic portion having protein tyrosine kinase activity. The highly conserved Ig-like domains 2 and 3, and the linker region between D2 and D3 define a general binding site for all FGFs.

Pssm-ID: 409362 Cd Length: 94 Bit Score: 49.51 E-value: 3.74e-07

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  515 PTRIYRMPEDQVARRGTTVQLECRVKHDPSlklTVSWLKDDEPLYIGNRMKKEDDSLTIFGVAERDQGSYTCVASTELDQ 594
Cdd:cd04973      9 PTYQISEVESYSAHPGDLLQLRCRLRDDVQ---SINWTKDGVQLGENNRTRITGEEVQIKDAVPRDSGLYACVTSSPSGS 85


                   .
gi 2217265369  595 D 595
Cdd:cd04973     86 D 86

Second immunoglobulin (Ig)-like domain of fibroblast growth factor (FGF) receptor, and similar domains; member of the I-set of IgSF domains; The members here are composed of the second immunoglobulin (Ig)-like domain of fibroblast growth factor (FGF) receptor. FGF receptors bind FGF signaling polypeptides. FGFs participate in multiple processes such as morphogenesis, development, and angiogenesis. FGFs bind to four FGF receptor tyrosine kinases (FGFR1, FGFR2, FGFR3, FGFR4). Receptor diversity is controlled by alternative splicing producing splice variants with different ligand binding characteristics and different expression patterns. FGFRs have an extracellular region comprised of three Ig-like domains, a single transmembrane helix, and an intracellular tyrosine kinase domain. Ligand binding and specificity reside in the Ig-like domains 2 and 3, and the linker region that connects these two. FGFR activation and signaling depend on FGF-induced dimerization, a process involving cell surface heparin or heparin sulfate proteoglycans. This group also contains fibroblast growth factor (FGF) receptor like-1(FGFRL1). FGFRL1 does not have a protein tyrosine kinase domain at its C-terminus; neither does its cytoplasmic domain appear to interact with a signaling partner. It has been suggested that FGFRL1 may not have any direct signaling function, but instead acts as a decoy receptor trapping FGFs and preventing them from binding other receptors.

Pssm-ID: 409393 [Multi-domain] Cd Length: 95 Bit Score: 49.53 E-value: 3.78e-07

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  424 PRMLSP---RNQLIRVILYNRTRLDCPFFGSPIPTLRWFKNGQ---GSNLDGGnYHVYENG-SLEIKMIRKEDQGIYTCV 496
Cdd:cd05729      1 PRFTDTekmEEREHALPAANKVRLECGAGGNPMPNITWLKDGKefkKEHRIGG-TKVEEKGwSLIIERAIPRDKGKYTCI 79

                           90
                   ....*....|....*.
gi 2217265369  497 ATNILGKAENQVRLEV 512
Cdd:cd05729     80 VENEYGSINHTYDVDV 95

Immunoglobulin (Ig)-like domain of myotilin, palladin, and myopalladin; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the immunoglobulin (Ig)-like domain in myotilin, palladin, and myopalladin. Myotilin, palladin, and myopalladin function as scaffolds that regulate actin organization. Myotilin and myopalladin are most abundant in skeletal and cardiac muscle; palladin is ubiquitously expressed in the organs of developing vertebrates and plays a key role in cellular morphogenesis. The three family members each interact with specific molecular partners with all three binding to alpha-actinin; In addition, palladin also binds to vasodilator-stimulated phosphoprotein (VASP) and ezrin, myotilin binds to filamin and actin, and myopalladin also binds to nebulin and cardiac ankyrin repeat protein (CARP). This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409405 [Multi-domain] Cd Length: 91 Bit Score: 49.03 E-value: 4.39e-07

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  238 PSFMYPQGtasSQMVLRGMDLLLECIASGVPTPDIAWYKKGGDL-PSDKAKF---ENFNKALRITNVSEEDSGEYFCLAS 313
Cdd:cd05744      1 PHFLQAPG---DLEVQEGRLCRFDCKVSGLPTPDLFWQLNGKPVrPDSAHKMlvrENGRHSLIIEPVTKRDAGIYTCIAR 77


                   ....
gi 2217265369  314 NKMG 317
Cdd:cd05744     78 NRAG 81

Second Ig-like domain of the giant muscle protein titin Z1z2 in the sarcomeric Z-disk, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the second immunoglobulin (Ig)-like domain of the giant muscle protein titin Z1z2 in the sarcomeric Z-disk and similar proteins. Titin is a key component in the assembly and functioning of vertebrate striated muscles. By providing connections at the level of individual microfilaments, it contributes to the fine balance of forces between the two halves of the sarcomere. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structure of the titin Z1z2 lacks this strand and thus it belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409564 [Multi-domain] Cd Length: 91 Bit Score: 49.12 E-value: 4.56e-07

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  423 PPRMLS-PRNQLIRVilYNRTRLDCPFFGSPIPTLRWFKNGQ--GSNLDggnYHVYENGSLEIKMIRK---EDQGIYTCV 496
Cdd:cd20972      1 PPQFIQkLRSQEVAE--GSKVRLECRVTGNPTPVVRWFCEGKelQNSPD---IQIHQEGDLHSLIIAEafeEDTGRYSCL 75

                           90
                   ....*....|....*.
gi 2217265369  497 ATNILGKAENQVRLEV 512
Cdd:cd20972     76 ATNSVGSDTTSAEIFV 91

Immunoglobulin (Ig)-like domain found in Perlecan and similar proteins; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the third immunoglobulin (Ig)-like domain found in Perlecan. Perlecan is a large multi-domain heparin sulfate proteoglycan, important in tissue development and organogenesis. Perlecan can be represented as 5 major portions; its fourth major portion (domain IV) is a tandem repeat of immunoglobulin-like domains (Ig2-Ig15) which can vary in size due to alternative splicing. Perlecan binds many cellular and extracellular ligands. Its domain IV region has many binding sites. Some of these have been mapped at the level of individual Ig-like domains, including a site restricted to the Ig5 domain for heparin/sulfatide, a site restricted to the Ig3 domain for nidogen-1 and nidogen-2, a site restricted to Ig4-5 for fibronectin, and sites restricted to Ig2 and to Ig13-15 for fibulin-2. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409412 Cd Length: 85 Bit Score: 48.71 E-value: 4.97e-07

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 2217265369  248 SSQMVLRGMDLLLECIA-SGVPTPDIAWYKKGGDLPSDKakfENFNKALRITNVSEEDSGEYFCLASN 314
Cdd:cd05754      9 RSQEVRPGADVSFICRAkSKSPAYTLVWTRVNGTLPSRA---MDFNGILTIRNVQLSDAGTYVCTGSN 73

Immunoglobulin (Ig)-like ectodomain of the LRIG1 (Leucine-rich Repeats And Immunoglobulin-like Domains Protein 1) and similar proteins; member of the I-set of IgSF domains; The members here are composed of subgroup of the immunoglobulin (Ig) domain found in the Ig superfamily. The Ig superfamily is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. A predominant feature of most Ig domains is a disulfide bridge connecting the two beta-sheets with a tryptophan residue packed against the disulfide bond. The ectodomain of LRIG1 has two distinct regions: the proposed 15 LRRs and three Ig-like domains closer to the membrane. LRIG1 has been reported to interact with many receptor tyrosine kinases, GDNF/c-Ret, E-cadherin, JAK/STAT, c-Met, and the EGFR family signaling systems. Immunoglobulin Superfamily (IgSF) domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. The structure of the LRIG1 extracellular Ig domain lacks a C" strand and thus is better described as a member of the I-set of IgSF domains.

Pssm-ID: 409420 [Multi-domain] Cd Length: 91 Bit Score: 48.38 E-value: 7.45e-07

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  520 RMPEDQVARRGTTVQLECRVKHDPSLKltVSWLKD---DEPLYIGNRMK--KEDDSLTIFGVAERDQGSYTCVASTELDQ 594
Cdd:cd05763      4 KTPHDITIRAGSTARLECAATGHPTPQ--IAWQKDggtDFPAARERRMHvmPEDDVFFIVDVKIEDTGVYSCTAQNSAGS 81

                           90
                   ....*....|
gi 2217265369  595 DLAKAYLTVL 604
Cdd:cd05763     82 ISANATLTVL 91

Fourth immunoglobulin (Ig)-like domain of peroxidasin; The members here are composed of the fourth immunoglobulin (Ig)-like domain in peroxidasin. Peroxidasin has a peroxidase domain and interacting extracellular motifs containing four Ig-like domains. It has been suggested that peroxidasin is secreted, and has functions related to the stabilization of the extracellular matrix. It may play a part in various other important processes such as removal and destruction of cells which have undergone programmed cell death and protection of the organism against non-self.

Pssm-ID: 143223 Cd Length: 69 Bit Score: 47.56 E-value: 7.81e-07

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 2217265369  443 RLDCPFFGSPIPTLRWFKNGQGSNlDGGNYHVYENGSLEIKMIRKEDQGIYTCVATNILGKAENQVRL 510
Cdd:cd05746      2 QIPCSAQGDPEPTITWNKDGVQVT-ESGKFHISPEGYLAIRDVGVADQGRYECVARNTIGYASVSMVL 68

Seventh immunoglobulin domain of the Drosophila melanogaster Dscam protein, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the seventh immunoglobulin domain of the Drosophila melanogaster Down syndrome cell adhesion molecule (DSCAM) protein and similar proteins. Down syndrome cell adhesion molecule (DSCAM) is a cell adhesion molecule that plays critical roles in neural development, including axon guidance and branching, axon target recognition, self-avoidance and synaptic formation. DSCAM belongs to the immunoglobulin superfamily and contributes to defects in the central nervous system in Down syndrome patients. Vertebrate DSCAMs differ from Drosophila Dscam1 in that they lack the extensive alternative splicing that occurs in the insect gene. Drosophila melanogaster Dscam has 38,016 isoforms generated by the alternative splicing of four variable exon clusters, which allows every neuron in the fly to display a distinctive set of Dscam proteins on its cell surface. Drosophila Dscam1 is a cell-surface protein that plays important roles in neural development and axon tiling of neurons. It is shown that thousands of isoforms bind themselves through specific homophilic (self-binding) interactions, a process which mediates cellular self-recognition. Drosophila Dscam2 is also alternatively spliced and plays a key role in the development of two visual system neurons, monopolar cells L1 and L2. This group is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand.

Pssm-ID: 409546 [Multi-domain] Cd Length: 96 Bit Score: 48.46 E-value: 8.70e-07

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  423 PPR-MLSPRNqlIRVILYNRTRLDCPFFGSPIPTLRWfKNGQGSN-------LDGGNYHVYENGSLEIKMIRKEDQGIYT 494
Cdd:cd20954      1 PPRwIVEPVD--ANVAAGQDVMLHCQADGFPTPTVTW-KKATGSTpgeykdlLYDPNVRILPNGTLVFGHVQKENEGHYL 77


                   ....*...
gi 2217265369  495 CVATNILG 502
Cdd:cd20954     78 CEAKNGIG 85

agrin-responsive first immunoglobulin-like domains (Ig1) of the MuSK ectodomain; a member of the I-set of IgSF domains; The members here are composed of the first immunoglobulin-like domains (Ig1) of the Muscle-specific kinase (MuSK). MuSK is a receptor tyrosine kinase specifically expressed in skeletal muscle, where it plays a central role in the formation and maintenance of the neuromuscular junction (NMJ). MuSK is activated by agrin, a neuron-derived heparan sulfate proteoglycan. The activation of MUSK in myotubes regulates the formation of NMJs through the regulation of different processes including the specific expression of genes in subsynaptic nuclei, the reorganization of the actin cytoskeleton and the clustering of the acetylcholine receptors (AChR) in the postsynaptic membrane. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structure of the MuSK lacks this strand and thus it belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409562 [Multi-domain] Cd Length: 92 Bit Score: 48.27 E-value: 9.20e-07

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  522 PEDQVARRGTTVQLECRVKHDPslKLTVSWLKDD---EPLYIGNRMKKEDDSLTIFGVAERDQGSYTCVASTELDQDLAK 598
Cdd:cd20970      9 SFTVTAREGENATFMCRAEGSP--EPEISWTRNGnliIEFNTRYIVRENGTTLTIRNIRRSDMGIYLCIASNGVPGSVEK 86


                   ..
gi 2217265369  599 AY 600
Cdd:cd20970     87 RI 88

Fibronectin type III domain;

Pssm-ID: 394996 [Multi-domain] Cd Length: 85 Bit Score: 48.18 E-value: 9.21e-07

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  822 APTEVKVRVMNSTAISLQWNRvySDTVQGQLREYRAYYWRESSLLKNLWVSQKRQQASFpgdrlrgVVSRLFPYSNYKLE 901
Cdd:pfam00041    2 APSNLTVTDVTSTSLTVSWTP--PPDGNGPITGYEVEYRPKNSGEPWNEITVPGTTTSV-------TLTGLKPGTEYEVR 72

                           90
                   ....*....|...
gi 2217265369  902 MVVVNGRGDGPRS 914
Cdd:pfam00041   73 VQAVNGGGEGPPS 85

Fibronectin type III domain;

Pssm-ID: 394996 [Multi-domain] Cd Length: 85 Bit Score: 47.79 E-value: 1.10e-06

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 2217265369 1115 WNVTVLP-NSKWANITWKHNF---GPGTDFVVEYIDSNHT--KKTVPVKAQAQPIQLTDLYPGMTYTLRVYSRDNEGIS 1187
Cdd:pfam00041    4 SNLTVTDvTSTSLTVSWTPPPdgnGPITGYEVEYRPKNSGepWNEITVPGTTTSVTLTGLKPGTEYEVRVQAVNGGGEG 82

Third immunoglobulin (Ig)-like domain of Neural Cell Adhesion Molecule 1 (NCAM-1); member of the I-set of IgSF domains; The members here are composed of the third immunoglobulin (Ig)-like domain of Neural Cell Adhesion Molecule (NCAM-1). NCAM plays important roles in the development and regeneration of the central nervous system, in synaptogenesis and neural migration. NCAM mediates cell-cell and cell-substratum recognition and adhesion via homophilic (NCAM-NCAM), and heterophilic (NCAM-non-NCAM), interactions. NCAM is expressed as three major isoforms having different intracellular extensions. The extracellular portion of NCAM has five N-terminal Ig-like domains and two fibronectin type III domains. The double zipper adhesion complex model for NCAM homophilic binding involves Ig1, Ig2, and Ig3. By this model, Ig1 and Ig2 mediate dimerization of NCAM molecules situated on the same cell surface (cis interactions), and Ig3 domains mediate interactions between NCAM molecules expressed on the surface of opposing cells (trans interactions) through binding to the Ig1 and Ig2 domains. The adhesive ability of NCAM is modulated by the addition of polysialic acid chains to the fifth Ig-like domain.

Pssm-ID: 143207 [Multi-domain] Cd Length: 95 Bit Score: 48.00 E-value: 1.10e-06

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 2217265369  442 TRLDCPFFGSPIPTLRWFKNGQGSNLDGGNYHVYENGS-LEIKMIRKEDQGIYTCVATNILGKAENQVRLEV 512
Cdd:cd05730     21 VTLACDADGFPEPTMTWTKDGEPIESGEEKYSFNEDGSeMTILDVDKLDEAEYTCIAENKAGEQEAEIHLKV 92

Fourth immunoglobulin (Ig)-like domain in neogenin, and similar domains; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the fourth immunoglobulin (Ig)-like domain in neogenin and related proteins. Neogenin is a cell surface protein which is expressed in the developing nervous system of vertebrate embryos in the growing nerve cells. It is also expressed in other embryonic tissues, and may play a general role in developmental processes such as cell migration, cell-cell recognition, and tissue growth regulation. Included in this group is the tumor suppressor protein DCC which is deleted in colorectal carcinoma. DCC and neogenin each have four Ig-like domains followed by six fibronectin type III domains, a transmembrane domain, and an intracellular domain. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409388 Cd Length: 84 Bit Score: 47.58 E-value: 1.15e-06

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 2217265369  256 MDLLLECIASGVPTPDIAWYKKGGD-LPSDKAKFENfNKALRITNVSEEDSGEYFCLASNKMGSIR 320
Cdd:cd05723     13 MDIVFECEVTGKPTPTVKWVKNGDVvIPSDYFKIVK-EHNLQVLGLVKSDEGFYQCIAENDVGNAQ 77

Immunoglobulin I-set domain of the Leucine-rich repeat and immunoglobin-like domain-containing protein 1 (Lingo-1); The members here are composed of the immunoglobulin I-set (IgI) domain of the Leucine-rich repeat and immunoglobin-like domain-containing protein 1 (Lingo-1). Human Lingo-1 is a central nervous system-specific transmembrane glycoprotein also known as LERN-1, which functions as a negative regulator of neuronal survival, axonal regeneration, and oligodendrocyte differentiation and myelination. Lingo-1 is a key component of the Nogo receptor signaling complex (RTN4R/NGFR) in RhoA activation responsible for some inhibition of axonal regeneration by myelin-associated factors. The ligand-binding ectodomain of human Lingo-1 contains a bimodular, kinked structure composed of leucine-rich repeat (LRR) and immunoglobulin (Ig)-like modules. Diseases associated with Lingo-1 include mental retardation, autosomal recessive 64 and essential tremor. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structure of the Lingo-1 lacks this strand and thus it belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409561 Cd Length: 92 Bit Score: 48.15 E-value: 1.20e-06

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  423 PPRMLSPRNQLIRVILYNRTRLDCPFFGSPIPTLRWFKNGQG--SNLDGGNYHVYENGSLEIKMIRKEDQGIYTCVATNI 500
Cdd:cd20969      1 RAAIRDRKAQQVFVDEGHTVQFVCRADGDPPPAILWLSPRKHlvSAKSNGRLTVFPDGTLEVRYAQVQDNGTYLCIAANA 80

                           90
                   ....*....|..
gi 2217265369  501 LGKAENQVRLEV 512
Cdd:cd20969     81 GGNDSMPAHLHV 92

IL-beta-binding protein; Provisional

Pssm-ID: 165149 [Multi-domain] Cd Length: 326 Bit Score: 51.94 E-value: 1.21e-06

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  478 GSLEIKMIRKEDQGIYTCVATNILG-KAENQ---VRLEVKD----PTriYRMPEDQVARRGTTVQLECRVK-HDPSLKLT 548
Cdd:PHA02785   177 GIITIEDVRKNDAGYYTCVLKYIYGdKTYNVtriVKLEVRDriipPT--MQLPEGVVTSIGSNLTIACRVSlRPPTTDAD 254

                           90       100       110       120       130
                   ....*....|....*....|....*....|....*....|....*....|....*....
gi 2217265369  549 VSWL-------KDDEP----LYIGNRMKKED------DSLTIFGVAERDQGSYTCVAST 590
Cdd:PHA02785   255 VFWIsngmyyeEDDEDgdgrISVANKIYTTDkrrvitSRLNINPVKEEDATTFTCMAFT 313

Immunoglobulin domain of human Synaptic Adhesion-Like Molecule 5 (SALM5) and similar proteins; member of the I-set of IgSF domains; This group contains the immunoglobulin domain of human Synaptic Adhesion-Like Molecule 5 (SALM5) and similar proteins. The SALM (for synaptic adhesion-like molecules; also known as Lrfn for leucine-rich repeat and fibronectin type III domain containing) family of adhesion molecules consists of five known members: SALM1/Lrfn2, SALM2/Lrfn1, SALM3/Lrfn4, SALM4/Lrfn3, and SALM5/Lrfn5. SALMs share a similar domain structure, containing leucine-rich repeats (LRRs), an immunoglobulin (Ig) domain, and a fibronectin III (FNIII) domain, followed by a transmembrane domain and a C-terminal PDZ-binding motif. SALM5 is implicated in autism spectrum disorders (ASDs) and schizophrenia, induces presynaptic differentiation in contacting axons. SALM5 interacts with the Ig domains of LAR (Leukocyte common Antigen-Related) family receptor protein tyrosine phosphatases (LAR-RPTPs; LAR, PTPdelta, and PTPsigma). In addition, PTPdelta is implicated in ASDs, ADHD, bipolar disorder, and restless leg syndrome. Studies have shown that LAR-RPTPs are novel and splicing-dependent presynaptic ligands for SALM5, and that they mediate SALM5-dependent presynaptic differentiation. Furthermore, SALM5 maintains AMPA receptor (AMPAR)-mediated excitatory synaptic transmission through mechanisms involving the interaction of SALM5 with LAR-RPTPs. This group belongs to the I-set of immunoglobulin superfamily (IgSF) domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand.

Pssm-ID: 409421 [Multi-domain] Cd Length: 88 Bit Score: 47.86 E-value: 1.24e-06

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  435 RVILYNRTRLDCPFFGSPIPTLRWFknGQGSNLDGGNYH--VYENGSLEIKMIRKEDQGIYTCVATNILGKAENQVRLEV 512
Cdd:cd05764     11 RVLEGQRATLRCKARGDPEPAIHWI--SPEGKLISNSSRtlVYDNGTLDILITTVKDTGAFTCIASNPAGEATARVELHI 88

Fourth Ig domain of the neural cell adhesion molecule contactin-2, and similar domains; The members here are composed of the fourth Ig domain of the neural cell adhesion molecule contactin-2. Contactins are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. Contactin-2 (also called TAG-1, axonin-1) facilitates cell adhesion by homophilic binding between molecules in apposed membranes. The first four Ig domains form the intermolecular binding fragment which arranges as a compact U-shaped module by contacts between Ig domains 1 and 4, and domains 2 and 3. It has been proposed that a linear zipper-like array forms, from contactin-2 molecules alternatively provided by the two apposed membranes.

Pssm-ID: 143205 [Multi-domain] Cd Length: 85 Bit Score: 47.59 E-value: 1.39e-06

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369   40 QSAKDHIVDPRDNILIECEAKGNPAPSFHWTRNSRffNIAKDPRVSMrrRSGTLVIDFRSggrpEEYEGEYQCFARNKFG 119
Cdd:cd05728      4 KVISDTEADIGSSLRWECKASGNPRPAYRWLKNGQ--PLASENRIEV--EAGDLRITKLS----LSDSGMYQCVAENKHG 75


                   ....*
gi 2217265369  120 TALSN 124
Cdd:cd05728     76 TIYAS 80

Seventh immunoglobulin domain of the Drosophila melanogaster Dscam protein, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the seventh immunoglobulin domain of the Drosophila melanogaster Down syndrome cell adhesion molecule (DSCAM) protein and similar proteins. Down syndrome cell adhesion molecule (DSCAM) is a cell adhesion molecule that plays critical roles in neural development, including axon guidance and branching, axon target recognition, self-avoidance and synaptic formation. DSCAM belongs to the immunoglobulin superfamily and contributes to defects in the central nervous system in Down syndrome patients. Vertebrate DSCAMs differ from Drosophila Dscam1 in that they lack the extensive alternative splicing that occurs in the insect gene. Drosophila melanogaster Dscam has 38,016 isoforms generated by the alternative splicing of four variable exon clusters, which allows every neuron in the fly to display a distinctive set of Dscam proteins on its cell surface. Drosophila Dscam1 is a cell-surface protein that plays important roles in neural development and axon tiling of neurons. It is shown that thousands of isoforms bind themselves through specific homophilic (self-binding) interactions, a process which mediates cellular self-recognition. Drosophila Dscam2 is also alternatively spliced and plays a key role in the development of two visual system neurons, monopolar cells L1 and L2. This group is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand.

Pssm-ID: 409546 [Multi-domain] Cd Length: 96 Bit Score: 47.69 E-value: 1.44e-06

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369   46 IVDPRD-------NILIECEAKGNPAPSFHWTRNS-----RFFNIAKDPRVSMRRrSGTLVIDFRSggrpEEYEGEYQCF 113
Cdd:cd20954      5 IVEPVDanvaagqDVMLHCQADGFPTPTVTWKKATgstpgEYKDLLYDPNVRILP-NGTLVFGHVQ----KENEGHYLCE 79

                           90
                   ....*....|....*..
gi 2217265369  114 ARNKFGTALSNRIRLQV 130
Cdd:cd20954     80 AKNGIGSGLSKVIFLKV 96

Second immunoglobulin (Ig)-like domain of protein tyrosine kinase (PTK) 7; The members here are composed of the second immunoglobulin (Ig)-like domain in protein tyrosine kinase (PTK) 7, also known as CCK4. PTK7 is a subfamily of the receptor protein tyrosine kinase family, and is referred to as an RPTK-like molecule. RPTKs transduce extracellular signals across the cell membrane and play important roles in regulating cell proliferation, migration, and differentiation. PTK7 is organized as an extracellular portion having seven Ig-like domains, a single transmembrane region, and a cytoplasmic tyrosine kinase-like domain. PTK7 is considered a pseudokinase as it has several unusual residues in some of the highly conserved tyrosine kinase (TK) motifs; it is predicted to lack TK activity. PTK7 may function as a cell-adhesion molecule. PTK7 mRNA is expressed at high levels in placenta, melanocytes, liver, lung, pancreas, and kidney. PTK7 is overexpressed in several cancers, including melanoma and colon cancer lines.

Pssm-ID: 409417 Cd Length: 95 Bit Score: 47.62 E-value: 1.47e-06

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369   35 PTITKQSAKDHIVDPRDNILIECEAKGNPAPSFHWTRNSrffNIAKDPR----VSMRRRSGTLvidfRSGGrpEEYEGEY 110
Cdd:cd05760      1 PVVLKHPASAAEIQPSSRVTLRCHIDGHPRPTYQWFRDG---TPLSDGQgnysVSSKERTLTL----RSAG--PDDSGLY 71

                           90
                   ....*....|....*
gi 2217265369  111 QCFARNKFGTALSNR 125
Cdd:cd05760     72 YCCAHNAFGSVCSSQ 86

Second C-terminal immunoglobulin (Ig)-like domain of palladin; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the C-terminal immunoglobulin (Ig)-like domain of palladin. Palladin belongs to the palladin-myotilin-myopalladin family. Proteins belonging to this family contain multiple Ig-like domains and function as scaffolds, modulating actin cytoskeleton. Palladin binds to alpha-actinin ezrin, vasodilator-stimulated phosphoprotein VASP, SPIN90 (also known as DIP or mDia interacting protein), and Src. Palladin also binds F-actin directly, via its Ig3 domain. Palladin is expressed as several alternatively spliced isoforms, having various combinations of Ig-like domains, in a cell-type-specific manner. It has been suggested that palladin's different Ig-like domains may be specialized for distinct functions. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409582 Cd Length: 91 Bit Score: 47.79 E-value: 1.53e-06

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 2217265369  443 RLDCPFFGSPIPTLRWFKNGQGSNLDGGNYH-VYENG--SLEIKMIRKEDQGIYTCVATNILGkaENQVRLEV 512
Cdd:cd20990     19 RMDCKVSGLPTPDLSWQLDGKPIRPDSAHKMlVRENGvhSLIIEPVTSRDAGIYTCIATNRAG--QNSFNLEL 89

Immunoglobulin (Ig)-like domain of titin and similar proteins; The members here are composed of the immunoglobulin (Ig)-like domain found in titin-like proteins and similar proteins. Titin (also called connectin) is a fibrous sarcomeric protein specifically found in vertebrate striated muscle. Titin is a giant protein; depending on isoform composition, it ranges from 2970 to 3700 kDa, and is of a length that spans half a sarcomere. Titin largely consists of multiple repeats of Ig-like and fibronectin type 3 (FN-III)-like domains. Titin connects the ends of myosin thick filaments to Z disks and extends along the thick filament to the H zone. It appears to function similarly to an elastic band, keeping the myosin filaments centered in the sarcomere during muscle contraction or stretching. Within the sarcomere, titin is also attached to or is associated with myosin binding protein C (MyBP-C). MyBP-C appears to contribute to the generation of passive tension by titin and like titin has repeated Ig-like and FN-III domains. Also included in this group are worm twitchin and insect projectin, thick filament proteins of invertebrate muscle which also have repeated Ig-like and FN-III domains.

Pssm-ID: 409406 [Multi-domain] Cd Length: 82 Bit Score: 47.20 E-value: 1.77e-06

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  251 MVLRGMDLLLECIASGVPTPDIAWYKKGGDL-PSDKAKFENFNKA--LRITNVSEEDSGEYFCLASNKMGSIRHTISVRV 327
Cdd:cd05748      3 VVRAGESLRLDIPIKGRPTPTVTWSKDGQPLkETGRVQIETTASStsLVIKNAKRSDSGKYTLTLKNSAGEKSATINVKV 82

Third immunoglobulin domain of the Drosophila melanogaster Dscam protein, and similar domains; a member of the Constant 2 (C2)-set of IgSF domains; The members here are composed of the third immunoglobulin domain of the Drosophila melanogaster Down syndrome cell adhesion molecule (DSCAM) protein and similar proteins. Down syndrome cell adhesion molecule (DSCAM) is a cell adhesion molecule that plays critical roles in neural development, including axon guidance and branching, axon target recognition, self-avoidance and synaptic formation. DSCAM belongs to the immunoglobulin superfamily and contributes to defects in the central nervous system in Down syndrome patients. Vertebrate DSCAMs differ from Drosophila Dscam1 in that they lack the extensive alternative splicing that occurs in the insect gene. Drosophila melanogaster Dscam has 38,016 isoforms generated by the alternative splicing of four variable exon clusters, which allows every neuron in the fly to display a distinctive set of Dscam proteins on its cell surface. Drosophila Dscam1 is a cell-surface protein that plays important roles in neural development and axon tiling of neurons. It is shown that thousands of isoforms bind themselves through specific homophilic (self-binding) interactions, a process which mediates cellular self-recognition. Drosophila Dscam2 is also alternatively spliced and plays a key role in the development of two visual system neurons, monopolar cells L1 and L2. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. This group belongs to the C2-set of IgSF domains, having A, B, and E strands in one beta-sheet and A', G, F, C, and C' in the other. Unlike other Ig domain sets, the C2-set lacks the D strand.

Pssm-ID: 409549 [Multi-domain] Cd Length: 88 Bit Score: 47.14 E-value: 1.99e-06

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  522 PEDQVARRGTTVQLECRVKHDPSLklTVSWLKDDEPLYIGNRMK-KEDDSLTIFGVAERDQGSYTCVASTELDQDLAKAY 600
Cdd:cd20957      8 PPVQTVDFGRTAVFNCSVTGNPIH--TVLWMKDGKPLGHSSRVQiLSEDVLVIPSVKREDKGMYQCFVRNDGDSAQATAE 85


                   .
gi 2217265369  601 L 601
Cdd:cd20957     86 L 86

First immunoglobulin (Ig) domain of contactin-5; member of the I-set of Ig superfamily domains; The members here are composed of the first immunoglobulin (Ig) domain of the neural cell adhesion molecule contactin-5. Contactins are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains, anchored to the membrane by glycosylphosphatidylinositol. The different contactins show different expression patterns in the central nervous system. In rats, a lack of contactin-5 (NB-2) results in an impairment of the neuronal activity in the auditory system. Contactin-5 is expressed specifically in the postnatal nervous system, peaking at about 3 weeks postnatal. Contactin-5 is highly expressed in the adult human brain in the occipital lobe and in the amygdala; lower levels of expression have been detected in the corpus callosum, caudate nucleus, and spinal cord. This group belongs to the I-set of IgSF domains.

Pssm-ID: 409435 Cd Length: 96 Bit Score: 47.24 E-value: 2.45e-06

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  331 PYWLDEPKNLILAPGEDGRLV---CRANGNPKPTVQWMVNGEPLQSAPPNPNREVAGDTIIFRDTQISSRAVYQCNTSNE 407
Cdd:cd05848      2 PVFVQEPDDAIFPTDSDEKKVilnCEARGNPVPTYRWLRNGTEIDTESDYRYSLIDGNLIISNPSEVKDSGRYQCLATNS 81


                   ....*.
gi 2217265369  408 HGYLLA 413
Cdd:cd05848     82 IGSILS 87

C5 immunoglobulin (Ig) domain of cardiac myosin binding protein C (MyBP-C); The members here are composed of the C5 immunoglobulin (Ig) domain of cardiac myosin binding protein C (MyBP-C). MyBP-C consists of repeated domains, Ig and fibronectin type 3, and various linkers. Three isoforms of MYBP-C exist: slow-skeletal (ssMyBP-C), fast-skeletal (fsMyBP-C), and cardiac (cMyBP-C). cMYBP-C has insertions between and inside domains and an additional cardiac-specific Ig domain at the N-terminus. For cMYBP_C an interaction has been demonstrated between this C5 domain and the Ig C8 domain.

Pssm-ID: 409475 Cd Length: 86 Bit Score: 46.76 E-value: 2.48e-06

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  434 IRVILYNRTRLDCPFFGSPIPTLRWFKNGQGSNLDGGNYHV---YENGSLEIKMIRKEDQGIYTCVATNILGkaENQVRL 510
Cdd:cd05894      5 IVVVAGNKLRLDVPISGEPAPTVTWSRGDKAFTATEGRVRVesyKDLSSFVIEGAEREDEGVYTITVTNPVG--EDHASL 82


                   ...
gi 2217265369  511 EVK 513
Cdd:cd05894     83 FVK 85

Immunoglobulin (Ig)-like domain in neuregulins; The members here are composed of the immunoglobulin (Ig)-like domain in neuregulins (NRGs). NRGs are signaling molecules which participate in cell-cell interactions in the nervous system, breast, heart, and other organ systems, and are implicated in the pathology of diseases including schizophrenia, multiple sclerosis, and breast cancer. There are four members of the neuregulin gene family (NRG-1, NRG-2, NRG-3, and NRG-4). The NRG-1 protein, binds to and activates the tyrosine kinases receptors ErbB3 and ErbB4, initiating signaling cascades. The other NRGs proteins bind one or the other or both of these ErbBs. NRG-1 has multiple functions: in the brain it regulates various processes such as radial glia formation and neuronal migration, dendritic development, and expression of neurotransmitters receptors, while in the peripheral nervous system NRG-1 regulates processes such as target cell differentiation, and Schwann cell survival. There are many NRG-1 isoforms which arise from the alternative splicing of mRNA. Less is known of the functions of the other NRGs. NRG-2 and NRG-3 are expressed predominantly in the nervous system. NRG-2 is expressed by motor neurons and terminal Schwann cells, and is concentrated near synaptic sites and may be a signal that regulates synaptic differentiation. NRG-4 has been shown to direct pancreatic islet cell development towards the delta-cell lineage.

Pssm-ID: 409408 [Multi-domain] Cd Length: 92 Bit Score: 47.12 E-value: 2.48e-06

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 2217265369  450 GSPIPTLRWFKNGQGSNLDGGNYHVYENGS----LEIKMIRKEDQGIYTCVATNILGKAENQVRLEV 512
Cdd:cd05750     26 ENPSPRYRWFKDGKELNRKRPKNIKIRNKKknseLQINKAKLEDSGEYTCVVENILGKDTVTGNVTV 92

Second C-terminal immunoglobulin (Ig)-like domain of palladin; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the C-terminal immunoglobulin (Ig)-like domain of palladin. Palladin belongs to the palladin-myotilin-myopalladin family. Proteins belonging to this family contain multiple Ig-like domains and function as scaffolds, modulating actin cytoskeleton. Palladin binds to alpha-actinin ezrin, vasodilator-stimulated phosphoprotein VASP, SPIN90 (also known as DIP or mDia interacting protein), and Src. Palladin also binds F-actin directly, via its Ig3 domain. Palladin is expressed as several alternatively spliced isoforms, having various combinations of Ig-like domains, in a cell-type-specific manner. It has been suggested that palladin's different Ig-like domains may be specialized for distinct functions. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409582 Cd Length: 91 Bit Score: 47.02 E-value: 2.64e-06

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  238 PSFMYPQGTASSQmvlRGMDLLLECIASGVPTPDIAWYKKGGDLPSDKAK----FENFNKALRITNVSEEDSGEYFCLAS 313
Cdd:cd20990      1 PHFLQAPGDLTVQ---EGKLCRMDCKVSGLPTPDLSWQLDGKPIRPDSAHkmlvRENGVHSLIIEPVTSRDAGIYTCIAT 77


                   ....
gi 2217265369  314 NKMG 317
Cdd:cd20990     78 NRAG 81

Fourth immunoglobulin (Ig)-like domain of L1, Ng-CAM (Neuron-glia CAM cell adhesion molecule), and NrCAM (Ng-CAM-related); The members here are composed of the fourth immunoglobulin (Ig)-like domain of L1, Ng-CAM (Neuron-glia CAM cell adhesion molecule), and NrCAM (Ng-CAM-related). These proteins belong to the L1 subfamily of cell adhesion molecules (CAMs) and are comprised of an extracellular region having six Ig-like domains and five fibronectin type III domains, a transmembrane region and an intracellular domain. These molecules are primarily expressed in the nervous system. L1 is associated with an X-linked recessive disorder, X-linked hydrocephalus, MASA syndrome, or spastic paraplegia type 1, that involves abnormalities of axonal growth.

Pssm-ID: 409367 [Multi-domain] Cd Length: 89 Bit Score: 46.67 E-value: 2.84e-06

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 2217265369  248 SSQMVLRGMDLLLECIASGVPTPDIAWYKKG---GDLPSDKAKFENfNKALRITNVSEEDSGEYFCLASNKMGSI 319
Cdd:cd04978      7 PSLVLSPGETGELICEAEGNPQPTITWRLNGvpiEPAPEDMRRTVD-GRTLIFSNLQPNDTAVYQCNASNVHGYL 80

Immunoglobulin I-set domain of the Leucine-rich repeat and immunoglobin-like domain-containing protein 1 (Lingo-1); The members here are composed of the immunoglobulin I-set (IgI) domain of the Leucine-rich repeat and immunoglobin-like domain-containing protein 1 (Lingo-1). Human Lingo-1 is a central nervous system-specific transmembrane glycoprotein also known as LERN-1, which functions as a negative regulator of neuronal survival, axonal regeneration, and oligodendrocyte differentiation and myelination. Lingo-1 is a key component of the Nogo receptor signaling complex (RTN4R/NGFR) in RhoA activation responsible for some inhibition of axonal regeneration by myelin-associated factors. The ligand-binding ectodomain of human Lingo-1 contains a bimodular, kinked structure composed of leucine-rich repeat (LRR) and immunoglobulin (Ig)-like modules. Diseases associated with Lingo-1 include mental retardation, autosomal recessive 64 and essential tremor. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structure of the Lingo-1 lacks this strand and thus it belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409561 Cd Length: 92 Bit Score: 46.61 E-value: 3.57e-06

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  328 KAAPYWLDEPKNLILapgedgrlVCRANGNPKPTVQWMVNGEPLQSAPPNPN-REVAGDTIIFRDTQISSRAVYQCNTSN 406
Cdd:cd20969      8 KAQQVFVDEGHTVQF--------VCRADGDPPPAILWLSPRKHLVSAKSNGRlTVFPDGTLEVRYAQVQDNGTYLCIAAN 79


                   ...
gi 2217265369  407 EHG 409
Cdd:cd20969     80 AGG 82

Third immunoglobulin (Ig) domain of contactin-1; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the third immunoglobulin (Ig) domain of the neural cell adhesion molecule contactin-1. Contactins are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. Contactin-1 is differentially expressed in tumor tissues and may through a RhoA mechanism, facilitate invasion and metastasis of human lung adenocarcinoma. This group belongs to the I-set of IgSF domains.

Pssm-ID: 143259 Cd Length: 88 Bit Score: 46.55 E-value: 3.68e-06

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  434 IRVILYNRTRLDCPFFGSPIPTLRWFKNGQGSNldgGNYHVYENGS-LEIKMIRKEDQGIYTCVATNILGKAENQVRLEV 512
Cdd:cd05851     11 TYALKGQNVTLECFALGNPVPVIRWRKILEPMP---ATAEISMSGAvLKIFNIQPEDEGTYECEAENIKGKDKHQARVYV 87


                   .
gi 2217265369  513 K 513
Cdd:cd05851     88 Q 88

Fourth Ig-like domain from smooth muscle myosin light chain kinase and similar domains ; a member of the I-set of IgSF domains; The members here are composed of the fourth immunoglobulin (Ig)-like domain from smooth muscle myosin light chain kinase (MYLK) and similar domains. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structure of this group shows that the fourth Ig-like domain from myosin light chain kinase lacks this strand and thus belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409568 [Multi-domain] Cd Length: 90 Bit Score: 46.47 E-value: 3.71e-06

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369   34 PPTITKQSAKDHIVDPRDNILiECEAKGNPAPSFHWTRNSRFFNIAKDpRVSMRRRSGTLVIdfrSGGRPEEYeGEYQCF 113
Cdd:cd20976      1 APSFSSVPKDLEAVEGQDFVA-QCSARGKPVPRITWIRNAQPLQYAAD-RSTCEAGVGELHI---QDVLPEDH-GTYTCL 74


                   ....*...
gi 2217265369  114 ARNKFGTA 121
Cdd:cd20976     75 AKNAAGQV 82

Third immunoglobulin (Ig) domain of contactin; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the third immunoglobulin (Ig) domain of contactins. Contactins are neural cell adhesion molecules and are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. The first four Ig domains form the intermolecular binding fragment, which arranges as a compact U-shaped module via contacts between Ig domains 1 and 4, and between Ig domains 2 and 3. Contactin-2 (TAG-1, axonin-1) may play a part in the neuronal processes of neurite outgrowth, axon guidance and fasciculation, and neuronal migration. This group also includes contactin-1 and contactin-5. The different contactins show different expression patterns in the central nervous system. During development and in adulthood, contactin-2 is transiently expressed in subsets of central and peripheral neurons. Contactin-5 is expressed specifically in the rat postnatal nervous system, peaking at about 3 weeks postnatal, and a lack of contactin-5 (NB-2) results in an impairment of neuronal activity in the rat auditory system. Contactin-5 is highly expressed in the adult human brain in the occipital lobe and in the amygdala. Contactin-1 is differentially expressed in tumor tissues and may, through a RhoA mechanism, facilitate invasion and metastasis of human lung adenocarcinoma. This group belongs to the I-set of IgSF domains.

Pssm-ID: 409357 [Multi-domain] Cd Length: 88 Bit Score: 46.39 E-value: 3.86e-06

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  515 PTRIYRMPEDQVARRGTTVQLECRVKHDPSLklTVSWLKDDEPLYIGNRMKKEDDSLTIFGVAERDQGSYTCVASTELDQ 594
Cdd:cd04968      1 PSIKVRFPADTYALKGQTVTLECFALGNPVP--QIKWRKVDGSPSSQWEITTSEPVLEIPNVQFEDEGTYECEAENSRGK 78


                   ....*....
gi 2217265369  595 DLAKAYLTV 603
Cdd:cd04968     79 DTVQGRIIV 87

immunoglobulin-like domain of telokin and similar proteins; a member of the I-set of IgSF domains; The members here are composed of the immunoglobulin (Ig) domain in telokin, the C-terminal domain of myosin light chain kinase which is identical to telokin, and similar proteins. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structure of the telokin Ig domain lacks this strand and thus it belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409565 [Multi-domain] Cd Length: 88 Bit Score: 46.41 E-value: 4.09e-06

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 2217265369  443 RLDCPFFGSPIPTLRWFKNGQG---SNLDGGNYHVYENGSLEIKMIRKEDQGIYTCVATNILGKAENQVRLEV 512
Cdd:cd20973     16 RFDCKVEGYPDPEVKWMKDDNPiveSRRFQIDQDEDGLCSLIISDVCGDDSGKYTCKAVNSLGEATCSAELTV 88

Fifth immunoglobulin (Ig) domain of contactin; The members here are composed of the fifth immunoglobulin (Ig) domain of contactins. Contactins are neural cell adhesion molecules and are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. The first four Ig domains form the intermolecular binding fragment, which arranges as a compact U-shaped module via contacts between Ig domains 1 and 4, and between Ig domains 2 and 3. Contactin-2 (TAG-1, axonin-1) may play a part in the neuronal processes of neurite outgrowth, axon guidance and fasciculation, and neuronal migration. This group also includes contactin-1 and contactin-5. The different contactins show different expression patterns in the central nervous system. During development and in adulthood, contactin-2 is transiently expressed in subsets of central and peripheral neurons. Contactin-5 is expressed specifically in the rat postnatal nervous system, peaking at about 3 weeks postnatal, and a lack of contactin-5 (NB-2) results in an impairment of neuronal activity in the rat auditory system. Contactin-5 is highly expressed in the adult human brain in the occipital lobe and in the amygdala. Contactin-1 is differentially expressed in tumor tissues and may, through a RhoA mechanism, facilitate invasion and metastasis of human lung adenocarcinoma.

Pssm-ID: 409358 [Multi-domain] Cd Length: 89 Bit Score: 46.30 E-value: 4.37e-06

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 2217265369  526 VARRGTTVQLECRVKHDPslKLTVSWLKDDEPLYIGNRMKKEDD-SLTIFGVAERDQGSYTCVASTELDQDLAKAYLTV 603
Cdd:cd04969     13 LAAKGGDVIIECKPKASP--KPTISWSKGTELLTNSSRICILPDgSLKIKNVTKSDEGKYTCFAVNFFGKANSTGSLSV 89

First immunoglobulin (Ig)-like domain in neogenin, and similar domains; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the first immunoglobulin (Ig)-like domain in neogenin and related proteins. Neogenin is a cell surface protein which is expressed in the developing nervous system of vertebrate embryos in the growing nerve cells. It is also expressed in other embryonic tissues and may play a general role in developmental processes such as cell migration, cell-cell recognition, and tissue growth regulation. Included in this group is the tumor suppressor protein DCC which is deleted in colorectal carcinoma. DCC and neogenin each have four Ig-like domains followed by six fibronectin type III domains, a transmembrane domain, and an intracellular domain. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409387 Cd Length: 97 Bit Score: 46.32 E-value: 4.42e-06

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|..
gi 2217265369  444 LDCPFFGSPIPTLRWFKNGQGSNLDGG-NYHVYENGSLEIKMI-----RKEDQGIYTCVATN 499
Cdd:cd05722     21 LNCSAESDPPPKIEWKKDGVLLNLVSDeRRQQLPNGSLLITSVvhskhNKPDEGFYQCVAQN 82

Fibronectin type III domain;

Pssm-ID: 394996 [Multi-domain] Cd Length: 85 Bit Score: 45.87 E-value: 4.67e-06

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  723 SNPGDVKGEGTRKNNMEITWTPmnATSAFGPNLRYIVKWRRRETREAWNNVTVWGSRY---VVGQTPvYVPYEIRVQAEN 799
Cdd:pfam00041    1 SAPSNLTVTDVTSTSLTVSWTP--PPDGNGPITGYEVEYRPKNSGEPWNEITVPGTTTsvtLTGLKP-GTEYEVRVQAVN 77


                   ....*..
gi 2217265369  800 DFGKGPE 806
Cdd:pfam00041   78 GGGEGPP 84

First Ig-like domain of the giant muscle protein titin Z1z2 in the sarcomeric Z-disk and similar proteins; a member of the I-set of IgSF domains; The members here are composed of the first immunoglobulin (Ig)-like domain of the giant muscle protein titin Z1z2 in the sarcomeric Z-disk and similar proteins. Titin is a key component in the assembly and functioning of vertebrate striated muscles. By providing connections at the level of individual microfilaments, it contributes to the fine balance of forces between the two halves of the sarcomere. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structure of the titin Z1z2 lacks this strand and thus it belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409566 [Multi-domain] Cd Length: 93 Bit Score: 46.19 E-value: 4.71e-06

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  248 SSQMVLRGMDLLLECIASGVPTPDIAWYKKG-----GDLPSDKAKFENFNKALRITNVSEEDSGEYFCLASNKMGSIRHT 322
Cdd:cd20974      8 QSVVVLEGSTATFEAHVSGKPVPEVSWFRDGqvistSTLPGVQISFSDGRAKLSIPAVTKANSGRYSLTATNGSGQATST 87


                   ....*.
gi 2217265369  323 ISVRVK 328
Cdd:cd20974     88 AELLVL 93

Immunoglobulin (Ig)-like domain of the human basement membrane heparan sulfate proteoglycan perlecan and similar proteins; The members here are composed of the immunoglobulin (Ig)-like domain of the human basement membrane heparan sulfate proteoglycan perlecan, also known as HSPG2, and similar proteins. Perlecan consists of five domains: domain I has three putative heparan sulfate attachment sites, domain II has four LDL receptor-like repeats, and one Ig-like repeat, domain III resembles the short arm of laminin chains, domain IV has multiple Ig-like repeats (21 repeats in human perlecan), and domain V resembles the globular G domain of the laminin A chain and internal repeats of EGF. Perlecan may participate in a variety of biological functions including cell binding, LDL-metabolism, basement membrane assembly and selective permeability, calcium binding, and growth- and neurite-promoting activities.

Pssm-ID: 143220 Cd Length: 78 Bit Score: 45.56 E-value: 5.00e-06

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 2217265369  255 GMDLLLECIASGVPTPDIAWYKKGGDLPSDKA---KFENFNKALRITNVSEEDSGEYFCLASNKMGSI 319
Cdd:cd05743      1 GETVEFTCVATGVPTPIINWRLNWGHVPDSARvsiTSEGGYGTLTIRDVKESDQGAYTCEAINTRGMV 68

Fibronectin type 3 domain; One of three types of internal repeats found in the plasma protein fibronectin. Its tenth fibronectin type III repeat contains an RGD cell recognition sequence in a flexible loop between 2 strands. Approximately 2% of all animal proteins contain the FN3 repeat; including extracellular and intracellular proteins, membrane spanning cytokine receptors, growth hormone receptors, tyrosine phosphatase receptors, and adhesion molecules. FN3-like domains are also found in bacterial glycosyl hydrolases.

Pssm-ID: 238020 [Multi-domain] Cd Length: 93 Bit Score: 46.34 E-value: 5.10e-06

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369 1116 NVTVLPNSK-WANITWK---HNFGPGTDFVVEYIDSNHTK-KTVPVKAQAQP-IQLTDLYPGMTYTLRVYSRDNEGIS-- 1187
Cdd:cd00063      6 NLRVTDVTStSVTLSWTppeDDGGPITGYVVEYREKGSGDwKEVEVTPGSETsYTLTGLKPGTEYEFRVRAVNGGGESpp 85


                   ....*...
gi 2217265369 1188 STVITFMT 1195
Cdd:cd00063     86 SESVTVTT 93

Second Ig-like domain of Junctional adhesion molecule-1 (JAM1); a member of the I-set of IgSF domains; The members here are composed of the second Ig-like domain of Junctional adhesion molecule-1 (JAM1). JAM1 is an immunoglobulin superfamily (IgSF) protein with two Ig-like domains in its extracellular region; it plays a role in the formation of endothelial and epithelial tight junction and acts as a receptor for mammalian reovirus sigma-1. The IgSF is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. The two sheets are linked together by a conserved disulfide bond between B strand and F strand. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. The second Ig-like domain of JAM1 is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, the A strand of the I-set is discontinuous but lacks a C" strand. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors.

Pssm-ID: 409542 Cd Length: 97 Bit Score: 46.16 E-value: 5.93e-06

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 2217265369  266 GVPTPDIAWYKKGGDLPSDKAKFENFNKA----------LRITNVSEEDSGEYFCLASNKMGSIRHTISVRVKA 329
Cdd:cd20950     24 GSPPSEYTWFKDGVVMPTNPKSTRAFSNSsysldpttgeLVFDPLSASDTGEYSCEARNGYGTPMRSNAVRMEA 97

Immunoglobulin (Ig)-like domain of the L1 cell adhesion molecule (CAM) and similar proteins; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the first immunoglobulin (Ig)-like domain of the L1 cell adhesion molecule (CAM). L1 belongs to the L1 subfamily of cell adhesion molecules (CAMs) and is comprised of an extracellular region having six Ig-like domains and five fibronectin type III domains, a transmembrane region and an intracellular domain. L1 is primarily expressed in the nervous system and is involved in its development and function. L1 is associated with an X-linked recessive disorder, X-linked hydrocephalus, MASA syndrome, or spastic paraplegia type 1, that involves abnormalities of axonal growth. This group also contains NrCAM [Ng(neuronglia)CAM-related cell adhesion molecule], which is primarily expressed in the nervous system, and human neurofascin. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lacks a C" strand.

Pssm-ID: 409396 [Multi-domain] Cd Length: 94 Bit Score: 45.86 E-value: 6.25e-06

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  337 PKNLILAPGEDGRLVCRANGNPKPTVQWMVNGEP--LQSAPPNPNREVAGDTII-FRDTQISS-RAVYQCNTSNEHGYLL 412
Cdd:cd05733      8 PKDYIVDPRDNITIKCEAKGNPQPTFRWTKDGKFfdPAKDPRVSMRRRSGTLVIdNHNGGPEDyQGEYQCYASNELGTAI 87


                   ..
gi 2217265369  413 AN 414
Cdd:cd05733     88 SN 89

Fibronectin type 3 domain; One of three types of internal repeat within the plasma protein, fibronectin. The tenth fibronectin type III repeat contains a RGD cell recognition sequence in a flexible loop between 2 strands. Type III modules are present in both extracellular and intracellular proteins.

Pssm-ID: 214495 [Multi-domain] Cd Length: 83 Bit Score: 45.30 E-value: 7.29e-06

                            10        20        30        40        50        60        70        80
                    ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369   822 APTEVKVRVMNSTAISLQWNRVYSDTVQGQLREYRAYYWRESSLLKNLWVSQKRQQASFPGdrlrgvvsrLFPYSNYKLE 901
Cdd:smart00060    3 PPSNLRVTDVTSTSVTLSWEPPPDDGITGYIVGYRVEYREEGSEWKEVNVTPSSTSYTLTG---------LKPGTEYEFR 73

                            90
                    ....*....|
gi 2217265369   902 MVVVNGRGDG 911
Cdd:smart00060   74 VRAVNGAGEG 83

C-terminal immunoglobulin (Ig)-like domain of myomesin and M-protein; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the C-terminal immunoglobulin (Ig)-like domain of myomesin and M-protein (also known as myomesin-2). Myomesin and M-protein are both structural proteins localized to the M-band, a transverse structure in the center of the sarcomere, and are candidates for M-band bridges. Both proteins are modular, consisting mainly of repetitive Ig-like and fibronectin type III (FnIII) domains. Myomesin is expressed in all types of vertebrate striated muscle; M-protein has a muscle-type specific expression pattern. Myomesin is present in both slow and fast fibers; M-protein is present only in fast fibers. It has been suggested that myomesin acts as a molecular spring with alternative splicing as a means of modifying its elasticity.

Pssm-ID: 319300 Cd Length: 92 Bit Score: 45.66 E-value: 7.36e-06

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  252 VLRGMDLLLECIASGVPTPDIAWYKKGGDLpsdkAKFENFNKALR--------ITNVSEEDSGEYFCLASNKMGS--IRH 321
Cdd:cd05737     13 IMEGKTLNLTCNVWGDPPPEVSWLKNDQAL----AFLDHCNLKVEagrtvyftINGVSSEDSGKYGLVVKNKYGSetSDV 88


                   ....
gi 2217265369  322 TISV 325
Cdd:cd05737     89 TVSV 92

Third immunoglobulin (Ig)-like domain of hemolin, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the third immunoglobulin (Ig)-like domain of hemolin and similar proteins. Hemolin, an insect immunoglobulin superfamily (IgSF) member containing four Ig-like domains, is a lipopolysaccharide-binding immune protein induced during bacterial infection. Hemolin shares significant sequence similarity with the first four Ig-like domains of the transmembrane cell adhesion molecules (CAMs) of the L1 family. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. The third Ig-like domain of hemolin is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand. I-set domains are found in several cell adhesion molecules, including vascular (VCAM), intercellular (ICAM), neural (NCAM) and mucosal addressin (MADCAM) cell adhesion molecules, as well as junction adhesion molecules (JAM).

Pssm-ID: 409569 Cd Length: 93 Bit Score: 45.84 E-value: 7.47e-06

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  243 PQGTASSQMVLRGMDLLLECIASGVPTPDIAWYKKGGDL---PSDKAKFENFN--KALRITNVSEEDSGEYFCLASNKMG 317
Cdd:cd20977      3 PQYVSKDMMAKAGDVTMIYCMYGSNPTAHPNYFKNGKDVngnPEDRITRHNRTsgKRLLFKTTLPEDEGVYTCEVDNGVG 82

                           90
                   ....*....|.
gi 2217265369  318 -SIRHTISVRV 327
Cdd:cd20977     83 kPQKHSLKLTV 93

Immunoglobulin I-set domain;

Pssm-ID: 400151 [Multi-domain] Cd Length: 90 Bit Score: 45.33 E-value: 8.24e-06

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369   35 PTITKQSaKDHIVDPRDNILIECEAKGNPAPSFHWTRNSRffNIAKDPRVSMRRRSG--TLVIDfrsgGRPEEYEGEYQC 112
Cdd:pfam07679    1 PKFTQKP-KDVEVQEGESARFTCTVTGTPDPEVSWFKDGQ--PLRSSDRFKVTYEGGtyTLTIS----NVQPDDSGKYTC 73

                           90
                   ....*....|....*...
gi 2217265369  113 FARNKFGTAlSNRIRLQV 130
Cdd:pfam07679   74 VATNSAGEA-EASAELTV 90

Fourth immunoglobulin (Ig)-like domain in neogenin, and similar domains; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the fourth immunoglobulin (Ig)-like domain in neogenin and related proteins. Neogenin is a cell surface protein which is expressed in the developing nervous system of vertebrate embryos in the growing nerve cells. It is also expressed in other embryonic tissues, and may play a general role in developmental processes such as cell migration, cell-cell recognition, and tissue growth regulation. Included in this group is the tumor suppressor protein DCC which is deleted in colorectal carcinoma. DCC and neogenin each have four Ig-like domains followed by six fibronectin type III domains, a transmembrane domain, and an intracellular domain. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409388 Cd Length: 84 Bit Score: 45.27 E-value: 9.03e-06

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 2217265369  444 LDCPFFGSPIPTLRWFKNGQGSnLDGGNYHVYENGSLEIKMIRKEDQGIYTCVATNILGKAENQVRL 510
Cdd:cd05723     17 FECEVTGKPTPTVKWVKNGDVV-IPSDYFKIVKEHNLQVLGLVKSDEGFYQCIAENDVGNAQASAQL 82

Fourth Ig domain of the neural cell adhesion molecule contactin-2, and similar domains; The members here are composed of the fourth Ig domain of the neural cell adhesion molecule contactin-2. Contactins are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. Contactin-2 (also called TAG-1, axonin-1) facilitates cell adhesion by homophilic binding between molecules in apposed membranes. The first four Ig domains form the intermolecular binding fragment which arranges as a compact U-shaped module by contacts between Ig domains 1 and 4, and domains 2 and 3. It has been proposed that a linear zipper-like array forms, from contactin-2 molecules alternatively provided by the two apposed membranes.

Pssm-ID: 143205 [Multi-domain] Cd Length: 85 Bit Score: 45.28 E-value: 9.51e-06

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  522 PEDQVARRGTTVQLECRVKHDPslKLTVSWLKDDEPLYIGNRMKKEDDSLTIFGVAERDQGSYTCVASTELDQDLAKAYL 601
Cdd:cd05728      6 ISDTEADIGSSLRWECKASGNP--RPAYRWLKNGQPLASENRIEVEAGDLRITKLSLSDSGMYQCVAENKHGTIYASAEL 83


                   ..
gi 2217265369  602 TV 603
Cdd:cd05728     84 AV 85

Fifth Ig-like domain of Roundabout (Robo) homolog 1/2, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the fifth Ig-like domain of Roundabout (Robo) homolog 1/2 and similar domains. Robo receptors play a role in the development of the central nervous system (CNS), and are receptors of Slit protein. Slit is a repellant secreted by the neural cells in the midline. Slit acts through Robo to prevent most neurons from crossing the midline from either side. Three mammalian Robo homologs (Robo1, -2, and -3), and three mammalian Slit homologs (Slit-1,-2, -3), have been identified. Commissural axons, which cross the midline, express low levels of Robo; longitudinal axons, which avoid the midline, express high levels of Robo. Robo1, -2, and -3 are expressed by commissural neurons in the vertebrate spinal cord and Slits 1, -2, -3 are expressed at the ventral midline. Robo-3 is a divergent member of the Robo family which instead of being a positive regulator of slit responsiveness, antagonizes slit responsiveness in precrossing axons. The Slit-Robo interaction is mediated by the second leucine-rich repeat (LRR) domain of Slit and the two N-terminal Ig domains of Robo, Ig1 and Ig2. The primary Robo binding site for Slit2 has been shown by surface plasmon resonance experiments and mutational analysis to be is the Ig1 domain, while the Ig2 domain has been proposed to harbor a weak secondary binding site. The fifth Ig-like domain of Robo 1 and 2 is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors

Pssm-ID: 409544 [Multi-domain] Cd Length: 87 Bit Score: 45.18 E-value: 1.10e-05

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369   37 ITKQSAKDHIVDPRDNILIECEAKGNPAPSFHWTRNSRFFnIAKDPRVSMrRRSGTLVIdfrSGGRPEEyEGEYQCFARN 116
Cdd:cd20952      1 IILQGPQNQTVAVGGTVVLNCQATGEPVPTISWLKDGVPL-LGKDERITT-LENGSLQI---KGAEKSD-TGEYTCVALN 74


                   ....*.
gi 2217265369  117 KFGTAL 122
Cdd:cd20952     75 LSGEAT 80

Immunoglobulin (Ig)-like ectodomain of the LRIG1 (Leucine-rich Repeats And Immunoglobulin-like Domains Protein 1) and similar proteins; member of the I-set of IgSF domains; The members here are composed of subgroup of the immunoglobulin (Ig) domain found in the Ig superfamily. The Ig superfamily is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. A predominant feature of most Ig domains is a disulfide bridge connecting the two beta-sheets with a tryptophan residue packed against the disulfide bond. The ectodomain of LRIG1 has two distinct regions: the proposed 15 LRRs and three Ig-like domains closer to the membrane. LRIG1 has been reported to interact with many receptor tyrosine kinases, GDNF/c-Ret, E-cadherin, JAK/STAT, c-Met, and the EGFR family signaling systems. Immunoglobulin Superfamily (IgSF) domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. The structure of the LRIG1 extracellular Ig domain lacks a C" strand and thus is better described as a member of the I-set of IgSF domains.

Pssm-ID: 409420 [Multi-domain] Cd Length: 91 Bit Score: 44.92 E-value: 1.26e-05

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  337 PKNLILAPGEDGRLVCRANGNPKPTVQWMVNGEPLQSAPPNPNREVAGDTIIF--RDTQISSRAVYQCNTSNEHGYLLAN 414
Cdd:cd05763      6 PHDITIRAGSTARLECAATGHPTPQIAWQKDGGTDFPAARERRMHVMPEDDVFfiVDVKIEDTGVYSCTAQNSAGSISAN 85


                   ....*.
gi 2217265369  415 AFVSVL 420
Cdd:cd05763     86 ATLTVL 91

Immunoglobulin (Ig)-like domain of myotilin, palladin, and myopalladin; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the immunoglobulin (Ig)-like domain in myotilin, palladin, and myopalladin. Myotilin, palladin, and myopalladin function as scaffolds that regulate actin organization. Myotilin and myopalladin are most abundant in skeletal and cardiac muscle; palladin is ubiquitously expressed in the organs of developing vertebrates and plays a key role in cellular morphogenesis. The three family members each interact with specific molecular partners with all three binding to alpha-actinin; In addition, palladin also binds to vasodilator-stimulated phosphoprotein (VASP) and ezrin, myotilin binds to filamin and actin, and myopalladin also binds to nebulin and cardiac ankyrin repeat protein (CARP). This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409405 [Multi-domain] Cd Length: 91 Bit Score: 44.41 E-value: 1.76e-05

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  331 PYWLDEPKNLILAPGEDGRLVCRANGNPKPTVQWMVNGEPLQ--SAPPNPNREVAGDTIIFRDTQISSRAVYQCNTSNEH 408
Cdd:cd05744      1 PHFLQAPGDLEVQEGRLCRFDCKVSGLPTPDLFWQLNGKPVRpdSAHKMLVRENGRHSLIIEPVTKRDAGIYTCIARNRA 80

                           90
                   ....*....|....
gi 2217265369  409 GyllANAFVSVLDV 422
Cdd:cd05744     81 G---ENSFNAELVV 91

Third immunoglobulin (Ig)-like domain of the receptor protein tyrosine phosphatase (RPTP)-F (also known as LAR), type IIa; member of the I-set of IgSF domains; The members here are composed of the third immunoglobulin (Ig)-like domain found in the receptor protein tyrosine phosphatase (RPTP)-F, also known as LAR. LAR belongs to the RPTP type IIa subfamily. Members of this subfamily are cell adhesion molecule-like proteins involved in central nervous system (CNS) development. They have large extracellular portions comprised of multiple Ig-like domains and two to nine fibronectin type III (FNIII) domains and a cytoplasmic portion having two tandem phosphatase domains. Included in this group is Drosophila LAR (DLAR).

Pssm-ID: 409401 Cd Length: 82 Bit Score: 44.12 E-value: 1.77e-05

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  248 SSQMVLRGMDLLLECIASGVPTPDIAWYKKGGDLPSDKAKFENFNkALRITNVSEedSGEYFCLASNKMGSIRHTISVRV 327
Cdd:cd05739      5 SNHEVMPGGSVNLTCVAVGAPMPYVKWMKGGEELTKEDEMPVGRN-VLELTNIYE--SANYTCVAISSLGMIEATAQVTV 81


                   .
gi 2217265369  328 K 328
Cdd:cd05739     82 K 82

First immunoglobulin (Ig) domain of contactin-5; member of the I-set of Ig superfamily domains; The members here are composed of the first immunoglobulin (Ig) domain of the neural cell adhesion molecule contactin-5. Contactins are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains, anchored to the membrane by glycosylphosphatidylinositol. The different contactins show different expression patterns in the central nervous system. In rats, a lack of contactin-5 (NB-2) results in an impairment of the neuronal activity in the auditory system. Contactin-5 is expressed specifically in the postnatal nervous system, peaking at about 3 weeks postnatal. Contactin-5 is highly expressed in the adult human brain in the occipital lobe and in the amygdala; lower levels of expression have been detected in the corpus callosum, caudate nucleus, and spinal cord. This group belongs to the I-set of IgSF domains.

Pssm-ID: 409435 Cd Length: 96 Bit Score: 44.55 E-value: 1.99e-05

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 2217265369  258 LLLECIASGVPTPDIAWYKKGG--DLPSDkAKFENFNKALRITNVSE-EDSGEYFCLASNKMGSI 319
Cdd:cd05848     22 VILNCEARGNPVPTYRWLRNGTeiDTESD-YRYSLIDGNLIISNPSEvKDSGRYQCLATNSIGSI 85

Second immunoglobulin (Ig)-like domain of fibroblast growth factor (FGF) receptor; member of the I-set of IgSF domains; The members here are composed of the second immunoglobulin (Ig)-like domain of fibroblast growth factor (FGF) receptor. FGF receptors bind FGF signaling polypeptides. FGFs participate in multiple processes such as morphogenesis, development, and angiogenesis. FGFs bind to four FGF receptor tyrosine kinases (FGFR1, FGFR2, FGFR3, FGFR4). Receptor diversity is controlled by alternative splicing producing splice variants with different ligand binding characteristics and different expression patterns. FGFRs have an extracellular region comprised of three IG-like domains, a single transmembrane helix, and an intracellular tyrosine kinase domain. Ligand binding and specificity reside in the Ig-like domains 2 and 3, and the linker region that connects these two. FGFR activation and signaling depend on FGF-induced dimerization, a process involving cell surface heparin or heparin sulfate proteoglycans.

Pssm-ID: 409443 [Multi-domain] Cd Length: 95 Bit Score: 44.46 E-value: 2.07e-05

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  331 PYWLDEP---KNLILAP-GEDGRLVCRANGNPKPTVQWMVNGEPLQsappnPNREVAG-------DTIIFRDTQISSRAV 399
Cdd:cd05857      1 PYWTNPEkmeKKLHAVPaANTVKFRCPAAGNPTPTMRWLKNGKEFK-----QEHRIGGykvrnqhWSLIMESVVPSDKGN 75

                           90
                   ....*....|
gi 2217265369  400 YQCNTSNEHG 409
Cdd:cd05857     76 YTCVVENEYG 85

Fourth immunoglobulin (Ig)-like domain of hemolin, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the fourth immunoglobulin (Ig)-like domain of hemolin and similar proteins. Hemolin, an insect immunoglobulin superfamily (IgSF) member containing four Ig-like domains, is a lipopolysaccharide-binding immune protein induced during bacterial infection. Hemolin shares significant sequence similarity with the first four Ig-like domains of the transmembrane cell adhesion molecules (CAMs) of the L1 family. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. The fourth Ig-like domain of hemolin is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set domains, members of the I-set have a discontinuous A strand but lack a C" strand. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409570 [Multi-domain] Cd Length: 88 Bit Score: 44.31 E-value: 2.17e-05

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369   35 PTITKQSAKDHIVDPRDNILIECEAKGNPAPSFHWTRNSRFFnIAKDPRVSMRRrsGTLVIdfrSGGRPEEyEGEYQCFA 114
Cdd:cd20978      1 PKFIQKPEKNVVVKGGQDVTLPCQVTGVPQPKITWLHNGKPL-QGPMERATVED--GTLTI---INVQPED-TGYYGCVA 73


                   ....*.
gi 2217265369  115 RNKFGT 120
Cdd:cd20978     74 TNEIGD 79

First immunoglobulin (Ig)-like domain of hemolin, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the first immunoglobulin (Ig)-like domain of hemolin and similar proteins. Hemolin, an insect immunoglobulin superfamily (IgSF) member containing four Ig-like domains, is a lipopolysaccharide-binding immune protein induced during bacterial infection. Hemolin shares significant sequence similarity with the first four Ig-like domains of the transmembrane cell adhesion molecules (CAMs) of the L1 family. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. The first Ig-like domain of hemolin is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand. I-set domains are found in several cell adhesion molecules, including vascular (VCAM), intercellular (ICAM), neural (NCAM) and mucosal addressin (MADCAM) cell adhesion molecules, as well as junction adhesion molecules (JAM).

Pssm-ID: 409571 Cd Length: 91 Bit Score: 44.48 E-value: 2.20e-05

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 2217265369   55 IECEAKG-NPAPSFHWTRNSRFFNIAKDpRVSMRRRSGTLVidFRsggRPEEY-EGEYQCFARNKFGTALSNRIRLQ 129
Cdd:cd20979     20 LECVTEGgDQGVKYSWLKDGKSFNWQEH-NVAQRKDEGSLV--FL---KPQASdEGQYQCFAETPAGVASSRVISFR 90

Third immunoglobulin domain of the Drosophila melanogaster Dscam protein, and similar domains; a member of the Constant 2 (C2)-set of IgSF domains; The members here are composed of the third immunoglobulin domain of the Drosophila melanogaster Down syndrome cell adhesion molecule (DSCAM) protein and similar proteins. Down syndrome cell adhesion molecule (DSCAM) is a cell adhesion molecule that plays critical roles in neural development, including axon guidance and branching, axon target recognition, self-avoidance and synaptic formation. DSCAM belongs to the immunoglobulin superfamily and contributes to defects in the central nervous system in Down syndrome patients. Vertebrate DSCAMs differ from Drosophila Dscam1 in that they lack the extensive alternative splicing that occurs in the insect gene. Drosophila melanogaster Dscam has 38,016 isoforms generated by the alternative splicing of four variable exon clusters, which allows every neuron in the fly to display a distinctive set of Dscam proteins on its cell surface. Drosophila Dscam1 is a cell-surface protein that plays important roles in neural development and axon tiling of neurons. It is shown that thousands of isoforms bind themselves through specific homophilic (self-binding) interactions, a process which mediates cellular self-recognition. Drosophila Dscam2 is also alternatively spliced and plays a key role in the development of two visual system neurons, monopolar cells L1 and L2. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. This group belongs to the C2-set of IgSF domains, having A, B, and E strands in one beta-sheet and A', G, F, C, and C' in the other. Unlike other Ig domain sets, the C2-set lacks the D strand.

Pssm-ID: 409549 [Multi-domain] Cd Length: 88 Bit Score: 44.06 E-value: 2.24e-05

                           10        20        30        40        50
                   ....*....|....*....|....*....|....*....|....*....|....*...
gi 2217265369  444 LDCPFFGSPIPTLRWFKNGQ--GSNldgGNYHVYENGSLEIKMIRKEDQGIYTCVATN 499
Cdd:cd20957     21 FNCSVTGNPIHTVLWMKDGKplGHS---SRVQILSEDVLVIPSVKREDKGMYQCFVRN 75

First immunoglobulin (Ig)-like constant domain in Robo (roundabout) receptors, and similar domains; The members here are composed of the first immunoglobulin (Ig)-like domain in Roundabout (Robo) receptors. Robo receptors play a role in the development of the central nervous system (CNS), and are receptors of Slit protein. Slit is a repellant secreted by the neural cells in the midline. Slit acts through Robo to prevent most neurons from crossing the midline from either side. Three mammalian Robo homologs (Robo1, Robo2, and Robo3), and three mammalian Slit homologs (Slit1, Slit2, Slit3), have been identified. Commissural axons, which cross the midline, express low levels of Robo; longitudinal axons, which avoid the midline, express high levels of Robo. Robo1, Robo2, and Robo3 are expressed by commissural neurons in the vertebrate spinal cord and Slit1, Slit2,and Slit3 are expressed at the ventral midline. Robo3 is a divergent member of the Robo family which instead of being a positive regulator of Slit responsiveness, antagonizes Slit responsiveness in precrossing axons. The Slit-Robo interaction is mediated by the second leucine-rich repeat (LRR) domain of Slit and the two N-terminal Ig domains of Robo, Ig1 and Ig2. The primary Robo binding site for Slit2 has been shown by surface plasmon resonance experiments and mutational analysis to be is the Ig1 domain, while the Ig2 domain has been proposed to harbor a weak secondary binding site.

Pssm-ID: 409490 [Multi-domain] Cd Length: 99 Bit Score: 44.46 E-value: 2.27e-05

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  517 RIYRMPEDQVARRGTTVQLECRVKHDPSlkLTVSWLKDDEPLYI------GNRMKKEDDSLTIFGV-----AERDQGSYT 585
Cdd:cd07693      2 RIVEHPSDLIVSKGDPATLNCKAEGRPT--PTIQWLKNGQPLETdkddprSHRIVLPSGSLFFLRVvhgrkGRSDEGVYV 79


                   ....*..
gi 2217265369  586 CVASTEL 592
Cdd:cd07693     80 CVAHNSL 86

Fourth Ig-like domain from smooth muscle myosin light chain kinase and similar domains ; a member of the I-set of IgSF domains; The members here are composed of the fourth immunoglobulin (Ig)-like domain from smooth muscle myosin light chain kinase (MYLK) and similar domains. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structure of this group shows that the fourth Ig-like domain from myosin light chain kinase lacks this strand and thus belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409568 [Multi-domain] Cd Length: 90 Bit Score: 44.16 E-value: 2.28e-05

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  330 APYWLDEPKNLILAPGEDGRLVCRANGNPKPTVQWMVNGEPLQSAPPNPNREVAGDTIIFRDTQISSRAVYQCNTSNEHG 409
Cdd:cd20976      1 APSFSSVPKDLEAVEGQDFVAQCSARGKPVPRITWIRNAQPLQYAADRSTCEAGVGELHIQDVLPEDHGTYTCLAKNAAG 80

                           90
                   ....*....|
gi 2217265369  410 YLLANAFVSV 419
Cdd:cd20976     81 QVSCSAWVTV 90

Fibronectin type 3 domain; One of three types of internal repeat within the plasma protein, fibronectin. The tenth fibronectin type III repeat contains a RGD cell recognition sequence in a flexible loop between 2 strands. Type III modules are present in both extracellular and intracellular proteins.

Pssm-ID: 214495 [Multi-domain] Cd Length: 83 Bit Score: 44.14 E-value: 2.36e-05

                            10        20        30        40        50        60        70
                    ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 2217265369  1116 NVTVLPNSK-WANITWKH-NFGPGTDFVVEYI----DSNHTKKTVPVKAQAQPIQLTDLYPGMTYTLRVYSRDNEGIS 1187
Cdd:smart00060    6 NLRVTDVTStSVTLSWEPpPDDGITGYIVGYRveyrEEGSEWKEVNVTPSSTSYTLTGLKPGTEYEFRVRAVNGAGEG 83

First immunoglobulin (Ig)-like domain in neogenin, and similar domains; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the first immunoglobulin (Ig)-like domain in neogenin and related proteins. Neogenin is a cell surface protein which is expressed in the developing nervous system of vertebrate embryos in the growing nerve cells. It is also expressed in other embryonic tissues and may play a general role in developmental processes such as cell migration, cell-cell recognition, and tissue growth regulation. Included in this group is the tumor suppressor protein DCC which is deleted in colorectal carcinoma. DCC and neogenin each have four Ig-like domains followed by six fibronectin type III domains, a transmembrane domain, and an intracellular domain. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409387 Cd Length: 97 Bit Score: 44.39 E-value: 2.56e-05

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 2217265369  253 LRGMDLLLECIASGVPTPDIAWYKKGG--DLPSDKAKFENFNKALRITNV-----SEEDSGEYFCLASNK-MGSI 319
Cdd:cd05722     14 MRGGPVVLNCSAESDPPPKIEWKKDGVllNLVSDERRQQLPNGSLLITSVvhskhNKPDEGFYQCVAQNEsLGSI 88

Fourth immunoglobulin (Ig)-like domain of L1, Ng-CAM (Neuron-glia CAM cell adhesion molecule), and NrCAM (Ng-CAM-related); The members here are composed of the fourth immunoglobulin (Ig)-like domain of L1, Ng-CAM (Neuron-glia CAM cell adhesion molecule), and NrCAM (Ng-CAM-related). These proteins belong to the L1 subfamily of cell adhesion molecules (CAMs) and are comprised of an extracellular region having six Ig-like domains and five fibronectin type III domains, a transmembrane region and an intracellular domain. These molecules are primarily expressed in the nervous system. L1 is associated with an X-linked recessive disorder, X-linked hydrocephalus, MASA syndrome, or spastic paraplegia type 1, that involves abnormalities of axonal growth.

Pssm-ID: 409367 [Multi-domain] Cd Length: 89 Bit Score: 43.98 E-value: 2.63e-05

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 2217265369   46 IVDPRDNILIECEAKGNPAPSFHWTRNSRFFNIAKdPRVSMRRRSGTLVIDFRSggrpEEYEGEYQCFARNKFGTALSN 124
Cdd:cd04978     10 VLSPGETGELICEAEGNPQPTITWRLNGVPIEPAP-EDMRRTVDGRTLIFSNLQ----PNDTAVYQCNASNVHGYLLAN 83

Third immunoglobulin (Ig)-like domain of the L1 cell adhesion molecule (CAM); The members here are composed of the third immunoglobulin (Ig)-like domain of the L1 cell adhesion molecule (CAM). L1 belongs to the L1 subfamily of cell adhesion molecules (CAMs) and is comprised of an extracellular region having six Ig-like domains, five fibronectin type III domains, a transmembrane region and an intracellular domain. L1 is primarily expressed in the nervous system and is involved in its development and function. L1 is associated with an X-linked recessive disorder, X-linked hydrocephalus, MASA syndrome, or spastic paraplegia type 1, that involves abnormalities of axonal growth. This group also contains the chicken neuron-glia cell adhesion molecule, Ng-CAM.

Pssm-ID: 409460 [Multi-domain] Cd Length: 83 Bit Score: 43.75 E-value: 2.78e-05

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  526 VARRGTTVQLECRVKHDPSLklTVSWLKDDEPLyIGNRMKKE--DDSLTIFGVAERDQGSYTCVASTELDQDLAKAYLTV 603
Cdd:cd05876      6 VALRGQSLVLECIAEGLPTP--TVKWLRPSGPL-PPDRVKYQnhNKTLQLLNVGESDDGEYVCLAENSLGSARHAYYVTV 82

Immunoglobulin (Ig)-like domain of titin and similar proteins; The members here are composed of the immunoglobulin (Ig)-like domain found in titin-like proteins and similar proteins. Titin (also called connectin) is a fibrous sarcomeric protein specifically found in vertebrate striated muscle. Titin is a giant protein; depending on isoform composition, it ranges from 2970 to 3700 kDa, and is of a length that spans half a sarcomere. Titin largely consists of multiple repeats of Ig-like and fibronectin type 3 (FN-III)-like domains. Titin connects the ends of myosin thick filaments to Z disks and extends along the thick filament to the H zone. It appears to function similarly to an elastic band, keeping the myosin filaments centered in the sarcomere during muscle contraction or stretching. Within the sarcomere, titin is also attached to or is associated with myosin binding protein C (MyBP-C). MyBP-C appears to contribute to the generation of passive tension by titin and like titin has repeated Ig-like and FN-III domains. Also included in this group are worm twitchin and insect projectin, thick filament proteins of invertebrate muscle which also have repeated Ig-like and FN-III domains.

Pssm-ID: 409406 [Multi-domain] Cd Length: 82 Bit Score: 43.73 E-value: 2.80e-05

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 2217265369  443 RLDCPFFGSPIPTLRWFKNGQGSNLDG-GNYHVYE-NGSLEIKMIRKEDQGIYTCVATNILGKAENQVRLEV 512
Cdd:cd05748     11 RLDIPIKGRPTPTVTWSKDGQPLKETGrVQIETTAsSTSLVIKNAKRSDSGKYTLTLKNSAGEKSATINVKV 82

Immunoglobulin (Ig)-like domain found in neuregulin (NRG)-1; The members here are composed of the immunoglobulin (Ig)-like domain found in neuregulin (NRG)-1. There are many NRG-1 isoforms which arise from the alternative splicing of mRNA. NRG-1 belongs to the neuregulin gene family which is comprised of four genes. This group represents NRG-1. NRGs are signaling molecules which participate in cell-cell interactions in the nervous system, breast, and heart, and other organ systems, and are implicated in the pathology of diseases including schizophrenia, multiple sclerosis, and breast cancer. The NRG-1 protein binds to and activates the tyrosine kinases receptors ErbB3 and ErbB4, initiating signaling cascades. NRG-1 has multiple functions, for example, in the brain it regulates various processes such as radial glia formation and neuronal migration, dendritic development, and expression of neurotransmitters receptors in the peripheral nervous system NRG-1 regulates processes such as target cell differentiation, and Schwann cell survival.

Pssm-ID: 409476 Cd Length: 93 Bit Score: 44.21 E-value: 2.86e-05

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  249 SQMVLRGMDLLLECIA-SGVPTPDIAWYKKGGDLpSDKAKFENFN-------KALRITNVSEEDSGEYFCLASNKMGSIR 320
Cdd:cd05895      8 SQEVAAGSKLVLRCETsSEYPSLRFKWFKNGKEI-NRKNKPENIKiqkkkkkSELRINKASLADSGEYMCKVSSKLGNDS 86


                   ....*..
gi 2217265369  321 HTISVRV 327
Cdd:cd05895     87 ASANVTI 93

Immunoglobulin domain; Members of the immunoglobulin superfamily are found in hundreds of proteins of different functions. Examples include antibodies, the giant muscle kinase titin and receptor tyrosine kinases. Immunoglobulin-like domains may be involved in protein-protein and protein-ligand interactions.

Pssm-ID: 395002 Cd Length: 86 Bit Score: 43.72 E-value: 3.17e-05

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 2217265369  252 VLRGMDLLLECIAS-GVPTPDIAWYKKGGDLPSDKAKFENFNK----ALRITNVSEEDSGEYFCLASN 314
Cdd:pfam00047    8 VLEGDSATLTCSAStGSPGPDVTWSKEGGTLIESLKVKHDNGRttqsSLLISNVTKEDAGTYTCVVNN 75

Fifth immunoglobulin (Ig) domain of contactin-1; The members here are composed of the fifth immunoglobulin (Ig) domain of the neural cell adhesion molecule contactin-1. Contactins are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. Contactin-1 is differentially expressed in tumor tissues and may through a RhoA mechanism, facilitate invasion and metastasis of human lung adenocarcinoma.

Pssm-ID: 409438 Cd Length: 89 Bit Score: 43.83 E-value: 3.26e-05

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 2217265369  521 MPEDQVARRGTTVQLECRVKHDPSLKLtvSWLKDDEPLYIGNRMKKEDD-SLTIFGVAERDQGSYTCVA 588
Cdd:cd05852      8 MKKKILAAKGGRVIIECKPKAAPKPKF--SWSKGTELLVNNSRISIWDDgSLEILNITKLDEGSYTCFA 74

Immunoglobulin (Ig)-like domain of human titin C terminus and similar proteins; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the fifth immunoglobulin (Ig)-like domain from the C-terminus of human titin x and similar proteins. Titin (also called connectin) is a fibrous sarcomeric protein specifically found in vertebrate striated muscle. Titin is gigantic; depending on isoform composition it ranges from 2970 to 3700 kDa, and is of a length that spans half a sarcomere. Titin largely consists of multiple repeats of Ig-like and fibronectin type 3 (FN-III)-like domains. Titin connects the ends of myosin thick filaments to Z disks and extends along the thick filament to the H zone and appears to function similar to an elastic band, keeping the myosin filaments centered in the sarcomere during muscle contraction or stretching. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 143224 [Multi-domain] Cd Length: 92 Bit Score: 43.88 E-value: 3.70e-05

                           10        20        30        40
                   ....*....|....*....|....*....|....*....|.
gi 2217265369  334 LDEPKNLILAPGEDGRLVCRANGNPKPTVQWMVNGEPLQSA 374
Cdd:cd05747      7 LTKPRSLTVSEGESARFSCDVDGEPAPTVTWMREGQIIVSS 47

Immunoglobulin (Ig)-like domain found in Perlecan and similar proteins; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the third immunoglobulin (Ig)-like domain found in Perlecan. Perlecan is a large multi-domain heparin sulfate proteoglycan, important in tissue development and organogenesis. Perlecan can be represented as 5 major portions; its fourth major portion (domain IV) is a tandem repeat of immunoglobulin-like domains (Ig2-Ig15) which can vary in size due to alternative splicing. Perlecan binds many cellular and extracellular ligands. Its domain IV region has many binding sites. Some of these have been mapped at the level of individual Ig-like domains, including a site restricted to the Ig5 domain for heparin/sulfatide, a site restricted to the Ig3 domain for nidogen-1 and nidogen-2, a site restricted to Ig4-5 for fibronectin, and sites restricted to Ig2 and to Ig13-15 for fibulin-2. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409412 Cd Length: 85 Bit Score: 43.31 E-value: 3.74e-05

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  522 PEDQVARRGTTVQLECRVKhDPSLKLTVSWLKDDEPLyiGNRMKKEDDSLTIFGVAERDQGSYTCVASTELDQDLAKAYL 601
Cdd:cd05754      8 PRSQEVRPGADVSFICRAK-SKSPAYTLVWTRVNGTL--PSRAMDFNGILTIRNVQLSDAGTYVCTGSNMLDTDEATATL 84

Second immunoglobulin (Ig)-like domain of a Follistatin-related protein 5, and similar domains; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the second immunoglobulin (Ig)-like domain found in human Follistatin-related protein 5 (FSTL5) and a follistatin-like molecule encoded by the CNS-related Mahya gene. Mahya genes have been retained in certain Bilaterian branches during evolution. They are conserved in Hymenoptera and Deuterostomes, but are absent from other metazoan species such as fruit fly and nematode. Mahya proteins are secretory, with a follistatin-like domain (Kazal-type serine/threonine protease inhibitor domain and EF-hand calcium-binding domain), two Ig-like domains, and a novel C-terminal domain. Mahya may be involved in learning and memory and in processing of sensory information in Hymenoptera and vertebrates. Follistatin is a secreted, multidomain protein that binds activins with high affinity and antagonizes their signaling.

Pssm-ID: 409399 [Multi-domain] Cd Length: 93 Bit Score: 43.79 E-value: 3.78e-05

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  517 RIYrmPEDQVARRGTTVQLECRVKHDPSLKLTvsWLKDDEPLyignrMKKEDDSLTIFG---------VAERDQGSYTCV 587
Cdd:cd05736      4 RVY--PEFQAKEPGVEASLRCHAEGIPLPRVQ--WLKNGMDI-----NPKLSKQLTLIAngselhisnVRYEDTGAYTCI 74

                           90
                   ....*....|..
gi 2217265369  588 ASTE--LDQDLA 597
Cdd:cd05736     75 AKNEggVDEDIS 86

Second immunoglobulin (Ig)-like domain of the receptor protein tyrosine phosphatase (RPTP)-F; member of the I-set of IgSF domains; The members here are composed of the second immunoglobulin (Ig)-like domain found in the receptor protein tyrosine phosphatase (RPTP)-F, also known as LAR. LAR belongs to the RPTP type IIa subfamily. Members of this subfamily are cell adhesion molecule-like proteins involved in central nervous system (CNS) development. They have large extracellular portions comprised of multiple Ig-like domains and two to nine fibronectin type III (FNIII) domains and a cytoplasmic portion having two tandem phosphatase domains.

Pssm-ID: 409400 [Multi-domain] Cd Length: 91 Bit Score: 43.46 E-value: 4.00e-05

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  419 VLDVPPRMlsprnqliRVILYNRT-RLDCPFFGSPIPTLRWFKNGQGSNLDGGNYHV--YENGSLEIKMIRKEDQGIYTC 495
Cdd:cd05738      1 IIDMGPQL--------KVVEKARTaTMLCAASGNPDPEISWFKDFLPVDTATSNGRIkqLRSGALQIENSEESDQGKYEC 72


                   ....*..
gi 2217265369  496 VATNILG 502
Cdd:cd05738     73 VATNSAG 79

Immunoglobulin (Ig)-like domain of Down Syndrome Cell Adhesion molecule (DSCAM); The members here are composed of the immunoglobulin (Ig)-like domain of Down Syndrome Cell Adhesion molecule (DSCAM). DSCAM is a cell adhesion molecule expressed largely in the developing nervous system. The gene encoding DSCAM is located at human chromosome 21q22, the locus associated with the intellectual disability phenotype of Down Syndrome. DSCAM is predicted to be the largest member of the IG superfamily. It has been demonstrated that DSCAM can mediate cation-independent homophilic intercellular adhesion.

Pssm-ID: 409397 [Multi-domain] Cd Length: 97 Bit Score: 43.64 E-value: 4.21e-05

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 2217265369  255 GMDLLLECIASGVPTPDIAW-YKKGGDLPSDKAKFEN-------FNKALRITNVSEEDSGEYFCLASNKMGS 318
Cdd:cd05734     16 GKAVVLNCSADGYPPPTIVWkHSKGSGVPQFQHIVPLngriqllSNGSLLIKHVLEEDSGYYLCKVSNDVGA 87

Fifth Ig-like domain of Roundabout (Robo) homolog 1/2, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the fifth Ig-like domain of Roundabout (Robo) homolog 1/2 and similar domains. Robo receptors play a role in the development of the central nervous system (CNS), and are receptors of Slit protein. Slit is a repellant secreted by the neural cells in the midline. Slit acts through Robo to prevent most neurons from crossing the midline from either side. Three mammalian Robo homologs (Robo1, -2, and -3), and three mammalian Slit homologs (Slit-1,-2, -3), have been identified. Commissural axons, which cross the midline, express low levels of Robo; longitudinal axons, which avoid the midline, express high levels of Robo. Robo1, -2, and -3 are expressed by commissural neurons in the vertebrate spinal cord and Slits 1, -2, -3 are expressed at the ventral midline. Robo-3 is a divergent member of the Robo family which instead of being a positive regulator of slit responsiveness, antagonizes slit responsiveness in precrossing axons. The Slit-Robo interaction is mediated by the second leucine-rich repeat (LRR) domain of Slit and the two N-terminal Ig domains of Robo, Ig1 and Ig2. The primary Robo binding site for Slit2 has been shown by surface plasmon resonance experiments and mutational analysis to be is the Ig1 domain, while the Ig2 domain has been proposed to harbor a weak secondary binding site. The fifth Ig-like domain of Robo 1 and 2 is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors

Pssm-ID: 409544 [Multi-domain] Cd Length: 87 Bit Score: 43.25 E-value: 4.23e-05

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  334 LDEPKNLILAPGEDGRLVCRANGNPKPTVQWMVNGEPLQSAPPNPNREVAGdTIIFRDTQISSRAVYQCNTSNEHGYLLA 413
Cdd:cd20952      3 LQGPQNQTVAVGGTVVLNCQATGEPVPTISWLKDGVPLLGKDERITTLENG-SLQIKGAEKSDTGEYTCVALNLSGEATW 81


                   ....*.
gi 2217265369  414 NAFVSV 419
Cdd:cd20952     82 SAVLDV 87

Immunoglobulin domain; Members of the immunoglobulin superfamily are found in hundreds of proteins of different functions. Examples include antibodies, the giant muscle kinase titin and receptor tyrosine kinases. Immunoglobulin-like domains may be involved in protein-protein and protein-ligand interactions.

Pssm-ID: 395002 Cd Length: 86 Bit Score: 42.95 E-value: 5.07e-05

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  521 MPEDQVARRGTTVQLECRVKHDPSLkLTVSWLKDD----EPLYIG-NRMKKEDDSLTIFGVAERDQGSYTCVASTELDQD 595
Cdd:pfam00047    2 APPTVTVLEGDSATLTCSASTGSPG-PDVTWSKEGgtliESLKVKhDNGRTTQSSLLISNVTKEDAGTYTCVVNNPGGSA 80

First immunoglobulin (Ig)-like constant domain in Robo (roundabout) receptors, and similar domains; The members here are composed of the first immunoglobulin (Ig)-like domain in Roundabout (Robo) receptors. Robo receptors play a role in the development of the central nervous system (CNS), and are receptors of Slit protein. Slit is a repellant secreted by the neural cells in the midline. Slit acts through Robo to prevent most neurons from crossing the midline from either side. Three mammalian Robo homologs (Robo1, Robo2, and Robo3), and three mammalian Slit homologs (Slit1, Slit2, Slit3), have been identified. Commissural axons, which cross the midline, express low levels of Robo; longitudinal axons, which avoid the midline, express high levels of Robo. Robo1, Robo2, and Robo3 are expressed by commissural neurons in the vertebrate spinal cord and Slit1, Slit2,and Slit3 are expressed at the ventral midline. Robo3 is a divergent member of the Robo family which instead of being a positive regulator of Slit responsiveness, antagonizes Slit responsiveness in precrossing axons. The Slit-Robo interaction is mediated by the second leucine-rich repeat (LRR) domain of Slit and the two N-terminal Ig domains of Robo, Ig1 and Ig2. The primary Robo binding site for Slit2 has been shown by surface plasmon resonance experiments and mutational analysis to be is the Ig1 domain, while the Ig2 domain has been proposed to harbor a weak secondary binding site.

Pssm-ID: 409490 [Multi-domain] Cd Length: 99 Bit Score: 43.31 E-value: 5.20e-05

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  444 LDCPFFGSPIPTLRWFKNGQ---GSNLDGGNYH-VYENGSLEIKMI-----RKEDQGIYTCVATNILGKA 504
Cdd:cd07693     20 LNCKAEGRPTPTIQWLKNGQpleTDKDDPRSHRiVLPSGSLFFLRVvhgrkGRSDEGVYVCVAHNSLGEA 89

Immunoglobulin (Ig)-like domain of myotilin, palladin, and myopalladin; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the immunoglobulin (Ig)-like domain in myotilin, palladin, and myopalladin. Myotilin, palladin, and myopalladin function as scaffolds that regulate actin organization. Myotilin and myopalladin are most abundant in skeletal and cardiac muscle; palladin is ubiquitously expressed in the organs of developing vertebrates and plays a key role in cellular morphogenesis. The three family members each interact with specific molecular partners with all three binding to alpha-actinin; In addition, palladin also binds to vasodilator-stimulated phosphoprotein (VASP) and ezrin, myotilin binds to filamin and actin, and myopalladin also binds to nebulin and cardiac ankyrin repeat protein (CARP). This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409405 [Multi-domain] Cd Length: 91 Bit Score: 43.25 E-value: 5.20e-05

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  520 RMPEDQVARRGTTVQLECRVKHDPSLKLTvsWLKDDEPLYIGNRMKKEDD-----SLTIFGVAERDQGSYTCVASTELDQ 594
Cdd:cd05744      5 QAPGDLEVQEGRLCRFDCKVSGLPTPDLF--WQLNGKPVRPDSAHKMLVRengrhSLIIEPVTKRDAGIYTCIARNRAGE 82


                   ....*....
gi 2217265369  595 DLAKAYLTV 603
Cdd:cd05744     83 NSFNAELVV 91

Second C-terminal immunoglobulin (Ig)-like domain of palladin; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the C-terminal immunoglobulin (Ig)-like domain of palladin. Palladin belongs to the palladin-myotilin-myopalladin family. Proteins belonging to this family contain multiple Ig-like domains and function as scaffolds, modulating actin cytoskeleton. Palladin binds to alpha-actinin ezrin, vasodilator-stimulated phosphoprotein VASP, SPIN90 (also known as DIP or mDia interacting protein), and Src. Palladin also binds F-actin directly, via its Ig3 domain. Palladin is expressed as several alternatively spliced isoforms, having various combinations of Ig-like domains, in a cell-type-specific manner. It has been suggested that palladin's different Ig-like domains may be specialized for distinct functions. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409582 Cd Length: 91 Bit Score: 43.17 E-value: 5.35e-05

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  331 PYWLDEPKNLILAPGEDGRLVCRANGNPKPTVQWMVNGEPLQ--SAPPNPNREVAGDTIIFRDTQISSRAVYQCNTSNEH 408
Cdd:cd20990      1 PHFLQAPGDLTVQEGKLCRMDCKVSGLPTPDLSWQLDGKPIRpdSAHKMLVRENGVHSLIIEPVTSRDAGIYTCIATNRA 80


                   .
gi 2217265369  409 G 409
Cdd:cd20990     81 G 81

Fourth immunoglobulin domain of the Drosophila melanogaster Dscam protein, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the fourth immunoglobulin domain of the Drosophila melanogaster Down syndrome cell adhesion molecule (DSCAM) protein and similar proteins. Down syndrome cell adhesion molecule (DSCAM) is a cell adhesion molecule that plays critical roles in neural development, including axon guidance and branching, axon target recognition, self-avoidance and synaptic formation. DSCAM belongs to the immunoglobulin superfamily and contributes to defects in the central nervous system in Down syndrome patients. Vertebrate DSCAMs differ from Drosophila Dscam1 in that they lack the extensive alternative splicing that occurs in the insect gene. Drosophila melanogaster Dscam has 38,016 isoforms generated by the alternative splicing of four variable exon clusters, which allows every neuron in the fly to display a distinctive set of Dscam proteins on its cell surface. Drosophila Dscam1 is a cell-surface protein that plays important roles in neural development and axon tiling of neurons. It is shown that thousands of isoforms bind themselves through specific homophilic (self-binding) interactions, a process which mediates cellular self-recognition. Drosophila Dscam2 is also alternatively spliced and plays a key role in the development of two visual system neurons, monopolar cells L1 and L2. This group is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand.

Pssm-ID: 409548 [Multi-domain] Cd Length: 96 Bit Score: 43.32 E-value: 5.53e-05

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 2217265369  444 LDCPFFGSPIPTLRWFKNGQGSNLDG----GNYhVYENG----SLEIKMIRKEDQGIYTCVATNILGKAENQVRLEV 512
Cdd:cd20956     21 LKCVASGNPLPQITWTLDGFPIPESPrfrvGDY-VTSDGdvvsYVNISSVRVEDGGEYTCTATNDVGSVSHSARINV 96

Immunoglobulin-like Ig0 domain of basigin-1 (BSG1) and similar proteins; The members here are composed of the immunoglobulin (Ig) domain of the collagenase stimulatory factor, basigin-1 (BSG1; also known as Cluster of Differentiation 147 (CD147) and Extracellular Matrix Metalloproteinase Inducer (EMMPRIN)) and similar proteins. CD147 is a transmembrane glycoprotein that belongs to the immunoglobulin superfamily. It is expressed in nearly all cells including platelets and fibroblasts and is involved in inflammatory diseases, and cancer progression. CD147 is highly expressed in several cancers and used as a prognostic marker. The two primary isoforms of CD147 that are related to cancer progression have been identified: CD147 Ig1-Ig2 (also called Basigin-2) that is ubiquitously expressed in most tissues and CD147 Ig0-Ig1-Ig2 (also called Basigin-1) that is retinal specific and implicated in retinoblastoma. Studies showed that CD147 Ig0 domain is a potent stimulator of interleukin-6 and suggest that the CD147 Ig0 dimer is the functional unit required for activity.

Pssm-ID: 409534 Cd Length: 116 Bit Score: 43.80 E-value: 5.65e-05

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  428 SPRNQliRVILYNRTRLDCPFFGSPIPTLRWFKNGQGSN------LDG---------GNYHVYENGSLEIKMIRKEDQGI 492
Cdd:cd20940      6 SPLSQ--QRLVGDSVELHCEAVGSPIPEIQWWFEGQEPNeicsqlWDGarldrvhinATYHQHATSTISIDNLTEEDTGT 83


                   ....*..
gi 2217265369  493 YTCVATN 499
Cdd:cd20940     84 YECRASN 90

First immunoglobulin domain of the Drosophila melanogaster Dscam protein, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the first immunoglobulin domain of the Drosophila melanogaster Down syndrome cell adhesion molecule (DSCAM) protein and similar proteins. Down syndrome cell adhesion molecule (DSCAM) is a cell adhesion molecule that plays critical roles in neural development, including axon guidance and branching, axon target recognition, self-avoidance and synaptic formation. DSCAM belongs to the immunoglobulin superfamily and contributes to defects in the central nervous system in Down syndrome patients. Vertebrate DSCAMs differ from Drosophila Dscam1 in that they lack the extensive alternative splicing that occurs in the insect gene. Drosophila melanogaster Dscam has 38,016 isoforms generated by the alternative splicing of four variable exon clusters, which allows every neuron in the fly to display a distinctive set of Dscam proteins on its cell surface. Drosophila Dscam1 is a cell-surface protein that plays important roles in neural development and axon tiling of neurons. It is shown that thousands of isoforms bind themselves through specific homophilic (self-binding) interactions, a process which mediates cellular self-recognition. Drosophila Dscam2 is also alternatively spliced and plays a key role in the development of two visual system neurons, monopolar cells L1 and L2. This group is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand.

Pssm-ID: 409547 Cd Length: 99 Bit Score: 43.17 E-value: 6.00e-05

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 2217265369   55 IECEAKGNPAPSFHWTRnSRFFNIAKDPRVSMRRRSGTLVI-DFRSGGRPEEYEGE-YQCFARNKFGTALSNRIRLQ 129
Cdd:cd20955     22 IECKASGNPMPEIIWIR-SDGTAVGDVPGLRQISSDGKLVFpPFRAEDYRQEVHAQvYACLARNQFGSIISRDVHVR 97

Immunoglobulin domain of human Synaptic Adhesion-Like Molecule 5 (SALM5) and similar proteins; member of the I-set of IgSF domains; This group contains the immunoglobulin domain of human Synaptic Adhesion-Like Molecule 5 (SALM5) and similar proteins. The SALM (for synaptic adhesion-like molecules; also known as Lrfn for leucine-rich repeat and fibronectin type III domain containing) family of adhesion molecules consists of five known members: SALM1/Lrfn2, SALM2/Lrfn1, SALM3/Lrfn4, SALM4/Lrfn3, and SALM5/Lrfn5. SALMs share a similar domain structure, containing leucine-rich repeats (LRRs), an immunoglobulin (Ig) domain, and a fibronectin III (FNIII) domain, followed by a transmembrane domain and a C-terminal PDZ-binding motif. SALM5 is implicated in autism spectrum disorders (ASDs) and schizophrenia, induces presynaptic differentiation in contacting axons. SALM5 interacts with the Ig domains of LAR (Leukocyte common Antigen-Related) family receptor protein tyrosine phosphatases (LAR-RPTPs; LAR, PTPdelta, and PTPsigma). In addition, PTPdelta is implicated in ASDs, ADHD, bipolar disorder, and restless leg syndrome. Studies have shown that LAR-RPTPs are novel and splicing-dependent presynaptic ligands for SALM5, and that they mediate SALM5-dependent presynaptic differentiation. Furthermore, SALM5 maintains AMPA receptor (AMPAR)-mediated excitatory synaptic transmission through mechanisms involving the interaction of SALM5 with LAR-RPTPs. This group belongs to the I-set of immunoglobulin superfamily (IgSF) domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand.

Pssm-ID: 409421 [Multi-domain] Cd Length: 88 Bit Score: 42.85 E-value: 6.25e-05

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 2217265369  252 VLRGMDLLLECIASGVPTPDIAWYKKGGDLPSDKAKFENF-NKALRITNVSEEDSGEYFCLASNKMGSIRHTISVRV 327
Cdd:cd05764     12 VLEGQRATLRCKARGDPEPAIHWISPEGKLISNSSRTLVYdNGTLDILITTVKDTGAFTCIASNPAGEATARVELHI 88

immunoglobulin-like domain of telokin and similar proteins; a member of the I-set of IgSF domains; The members here are composed of the immunoglobulin (Ig) domain in telokin, the C-terminal domain of myosin light chain kinase which is identical to telokin, and similar proteins. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structure of the telokin Ig domain lacks this strand and thus it belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409565 [Multi-domain] Cd Length: 88 Bit Score: 42.95 E-value: 6.44e-05

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 2217265369  260 LECIASGVPTPDIAWYKKGGDL-PSDKAKF---ENFNKALRITNVSEEDSGEYFCLASNKMGSIRHTISVRV 327
Cdd:cd20973     17 FDCKVEGYPDPEVKWMKDDNPIvESRRFQIdqdEDGLCSLIISDVCGDDSGKYTCKAVNSLGEATCSAELTV 88

First immunoglobulin (Ig) domain of contactin; member of the I-set of (Ig) superfamily domains; The members here are composed of the first immunoglobulin (Ig) domain of contactins. Contactins are neural cell adhesion molecules and are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. The first four Ig domains form the intermolecular binding fragment, which arranges as a compact U-shaped module via contacts between Ig domains 1 and 4, and between Ig domains 2 and 3. Contactin-2 (TAG-1, axonin-1) may play a part in the neuronal processes of neurite outgrowth, axon guidance and fasciculation, and neuronal migration. This group also includes contactin-1 and contactin-5. The different contactins show different expression patterns in the central nervous system. During development and in adulthood, contactin-2 is transiently expressed in subsets of central and peripheral neurons. Contactin-5 is expressed specifically in the rat postnatal nervous system, peaking at about 3 weeks postnatal, and a lack of contactin-5 (NB-2) results in an impairment of neuronal activity in the rat auditory system. Contactin-5 is highly expressed in the adult human brain in the occipital lobe and in the amygdala. Contactin-1 is differentially expressed in tumor tissues and may, through a RhoA mechanism, facilitate invasion and metastasis of human lung adenocarcinoma. This group belongs to the I-set of IgSF domains.

Pssm-ID: 409356 [Multi-domain] Cd Length: 96 Bit Score: 43.00 E-value: 6.58e-05

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  241 MYPQGTASSQMVLrgmdlllECIASGVPTPDIAWYKKGGDL---PSDKAKFENFNkaLRITNVSE-EDSGEYFCLASNKM 316
Cdd:cd04967     12 IFPEDSDEKKVAL-------NCRARANPVPSYRWLMNGTEIdleSDYRYSLVDGT--LVISNPSKaKDAGHYQCLATNTV 82


                   ....*.
gi 2217265369  317 GSIRHT 322
Cdd:cd04967     83 GSVLSR 88

Second immunoglobulin (Ig)-like domain of the receptor protein tyrosine phosphatase (RPTP)-F; member of the I-set of IgSF domains; The members here are composed of the second immunoglobulin (Ig)-like domain found in the receptor protein tyrosine phosphatase (RPTP)-F, also known as LAR. LAR belongs to the RPTP type IIa subfamily. Members of this subfamily are cell adhesion molecule-like proteins involved in central nervous system (CNS) development. They have large extracellular portions comprised of multiple Ig-like domains and two to nine fibronectin type III (FNIII) domains and a cytoplasmic portion having two tandem phosphatase domains.

Pssm-ID: 409400 [Multi-domain] Cd Length: 91 Bit Score: 43.08 E-value: 6.78e-05

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|..
gi 2217265369  262 CIASGVPTPDIAWYKKGgdLPSDKAKFENFNKALR-----ITNVSEEDSGEYFCLASNKMGS 318
Cdd:cd05738     21 CAASGNPDPEISWFKDF--LPVDTATSNGRIKQLRsgalqIENSEESDQGKYECVATNSAGT 80

C-terminal immunoglobulin-like domain of the myosin-associated giant protein kinase Twitchin, and similar domains; member of the I-set IgSF domains; The members here are composed of the C-terminal immunoglobulin-like domain of the myosin-associated giant protein kinase Twitchin and similar proteins, including Caenorhabditis elegans and Aplysia californica Twitchin, Drosophila melanogaster Projectin, and similar proteins. These are very large muscle proteins containing multiple immunoglobulin (Ig)-like and fibronectin type III (FN3) domains and a single kinase domain near the C-terminus. In humans these proteins are called Titin. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. The Ig-like domain of the Twitchin is a member of the I-set IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins (titin, telokin, and twitchin), the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D.

Pssm-ID: 409541 [Multi-domain] Cd Length: 89 Bit Score: 42.70 E-value: 6.79e-05

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  446 CPFFGSPIPTLRWFKNGQ---GSNLDGGNYHVYENGsLEIKMIRKEDQGIYTCVATNILGKAENQVRLEV 512
Cdd:cd20949     21 CEVKGEPQPNVTWHFNGQpisASVADMSKYRILADG-LLINKVTQDDTGEYTCRAYQVNSIASDMQERTV 89

Second immunoglobulin (Ig)-like domain of fibroblast growth factor (FGF) receptor_like-1(FGFRL1); member of the I-set of IgSF domains; The members here are composed of the second immunoglobulin (Ig)-like domain of fibroblast growth factor (FGF) receptor like-1(FGFRL1). FGFRL1 is comprised of a signal peptide, three extracellular Ig-like modules, a transmembrane segment, and a short intracellular domain. FGFRL1 is expressed preferentially in skeletal tissues. Similar to FGF receptors, the expressed protein interacts specifically with heparin and with FGF2. FGFRL1 does not have a protein tyrosine kinase domain at its C-terminus; neither does its cytoplasmic domain appear to interact with a signaling partner. It has been suggested that FGFRL1 may not have any direct signaling function, but instead acts as a decoy receptor trapping FGFs and preventing them from binding other receptors.

Pssm-ID: 409442 Cd Length: 92 Bit Score: 42.92 E-value: 6.87e-05

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  338 KNLILAP-GEDGRLVCRANGNPKPTVQWMVNGEPLQSAPPNPNREVAGdTIIFRDTQISSRAVYQCNTSNEHGYLLANAF 416
Cdd:cd05856     11 RRVIARPvGSSVRLKCVASGNPRPDITWLKDNKPLTPPEIGENKKKKW-TLSLKNLKPEDSGKYTCHVSNRAGEINATYK 89


                   ...
gi 2217265369  417 VSV 419
Cdd:cd05856     90 VDV 92

Fourth immunoglobulin (Ig)-like domain of L1, Ng-CAM (Neuron-glia CAM cell adhesion molecule), and NrCAM (Ng-CAM-related); The members here are composed of the fourth immunoglobulin (Ig)-like domain of L1, Ng-CAM (Neuron-glia CAM cell adhesion molecule), and NrCAM (Ng-CAM-related). These proteins belong to the L1 subfamily of cell adhesion molecules (CAMs) and are comprised of an extracellular region having six Ig-like domains and five fibronectin type III domains, a transmembrane region and an intracellular domain. These molecules are primarily expressed in the nervous system. L1 is associated with an X-linked recessive disorder, X-linked hydrocephalus, MASA syndrome, or spastic paraplegia type 1, that involves abnormalities of axonal growth.

Pssm-ID: 409367 [Multi-domain] Cd Length: 89 Bit Score: 42.44 E-value: 9.02e-05

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  522 PEDQVARRGTTVQLECRVKHDPslKLTVSWLKDDEPLYI---GNRMKKEDDSLTIFGVAERDQGSYTCVASTELDQDLAK 598
Cdd:cd04978      6 PPSLVLSPGETGELICEAEGNP--QPTITWRLNGVPIEPapeDMRRTVDGRTLIFSNLQPNDTAVYQCNASNVHGYLLAN 83


                   ....*.
gi 2217265369  599 AYLTVL 604
Cdd:cd04978     84 AFLHVL 89

Immunoglobulin (Ig)-like domain of NrCAM (Ng (neuronglia) CAM-related cell adhesion molecule); member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the first immunoglobulin (Ig)-like domain of NrCAM (Ng (neuronglia) CAM-related cell adhesion molecule). NrCAM belongs to the L1 subfamily of cell adhesion molecules (CAMs) and is comprised of an extracellular region having six Ig-like domains and five fibronectin type III domains, a transmembrane region, and an intracellular domain. NrCAM is primarily expressed in the nervous system.

Pssm-ID: 409458 Cd Length: 95 Bit Score: 42.66 E-value: 9.45e-05

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  337 PKNLILAPGEDGRLVCRANGNPKPTVQWMVNG-------EPLQSAPPNpnrevAGDTIIfrDTQISSRA-----VYQCNT 404
Cdd:cd05874      8 PKDYIVDPRENIVIQCEAKGKPPPSFSWTRNGthfdidkDPKVTMKPN-----TGTLVI--NIMNGEKAeayegVYQCTA 80

                           90
                   ....*....|...
gi 2217265369  405 SNEHGYLLANAFV 417
Cdd:cd05874     81 RNERGAAVSNNIV 93

Immunoglobulin (Ig)-like domain of human carcinoembryonic antigen (CEA) related cell adhesion molecule (CEACAM) domains 2, 4, and 6, and similar domains; The members here are composed of the second, fourth, and sixth immunoglobulin (Ig)-like domains in human carcinoembryonic antigen (CEA) related cell adhesion molecule (CEACAM) protein subfamily. The CEA family is a group of anchored or secreted glycoproteins expressed by epithelial cells, leukocytes, endothelial cells, and placenta. The CEA family is divided into the CEACAM and pregnancy-specific glycoprotein (PSG) subfamilies. This group represents the CEACAM subfamily. CEACAM1 has many important cellular functions; it is a cell adhesion molecule and a signaling molecule that regulates the growth of tumor cells, an angiogenic factor, and a receptor for bacterial and viral pathogens, including mouse hepatitis virus (MHV). In mice, four isoforms of CEACAM1 generated by alternative splicing have either two [D1, D4] or four [D1-D4] Ig-like domains on the cell surface.

Pssm-ID: 409402 [Multi-domain] Cd Length: 89 Bit Score: 42.38 E-value: 1.03e-04

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|..
gi 2217265369  260 LECIASGvPTPDIAWYKKGGDLP-SDKAKFENFNKALRITNVSEEDSGEYFCLASNKMGSIR 320
Cdd:cd05740     20 LTCEPET-QNTSYLWWFNGQSLPvTPRLTLSNGNRTLTLLNVTREDAGAYQCEISNPVSANR 80

Sixth immunoglobulin (Ig) domain of contactin-4; The members here are composed of the sixth immunoglobulin (Ig) domain of the neural cell adhesion molecule contactin-4. Contactins are neural cell adhesion molecules, and are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. The different contactins show different expression patterns in the central nervous system. Highest expression of contactin-4 is in testes, thyroid, small intestine, uterus, and brain. Contactin-4 plays a role in the response of neuroblastoma cells to differentiating agents, such as retinoids. The contactin 4 gene is associated with cerebellar degeneration in spinocerebellar ataxia type 16.

Pssm-ID: 409439 Cd Length: 102 Bit Score: 42.69 E-value: 1.05e-04

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  514 DPTRIYRMPEDQVARRGTTVQLECRVKHDPSLKLTVSWL---------KDDEPLyigNRMKKEDDS--LTIFGVAERDQG 582
Cdd:cd05853      1 DPTRVMVPPSSMDVTVGESIVLPCQVSHDHSLDIVFTWSfnghlidfqKDGDHF---ERVGGQDSAgdLMIRSIQLKHAG 77

                           90       100
                   ....*....|....*....|.
gi 2217265369  583 SYTCVASTELDQDLAKAYLTV 603
Cdd:cd05853     78 KYVCMVQTSVDKLSAAADLIV 98

Seventh immunoglobulin domain of the Drosophila melanogaster Dscam protein, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the seventh immunoglobulin domain of the Drosophila melanogaster Down syndrome cell adhesion molecule (DSCAM) protein and similar proteins. Down syndrome cell adhesion molecule (DSCAM) is a cell adhesion molecule that plays critical roles in neural development, including axon guidance and branching, axon target recognition, self-avoidance and synaptic formation. DSCAM belongs to the immunoglobulin superfamily and contributes to defects in the central nervous system in Down syndrome patients. Vertebrate DSCAMs differ from Drosophila Dscam1 in that they lack the extensive alternative splicing that occurs in the insect gene. Drosophila melanogaster Dscam has 38,016 isoforms generated by the alternative splicing of four variable exon clusters, which allows every neuron in the fly to display a distinctive set of Dscam proteins on its cell surface. Drosophila Dscam1 is a cell-surface protein that plays important roles in neural development and axon tiling of neurons. It is shown that thousands of isoforms bind themselves through specific homophilic (self-binding) interactions, a process which mediates cellular self-recognition. Drosophila Dscam2 is also alternatively spliced and plays a key role in the development of two visual system neurons, monopolar cells L1 and L2. This group is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand.

Pssm-ID: 409546 [Multi-domain] Cd Length: 96 Bit Score: 42.30 E-value: 1.25e-04

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  331 PYWLDEPKNLILAPGEDGRLVCRANGNPKPTVQWMvngeplQSAPPNPN--REVAGD---------TIIFRDTQISSRAV 399
Cdd:cd20954      2 PRWIVEPVDANVAAGQDVMLHCQADGFPTPTVTWK------KATGSTPGeyKDLLYDpnvrilpngTLVFGHVQKENEGH 75

                           90
                   ....*....|
gi 2217265369  400 YQCNTSNEHG 409
Cdd:cd20954     76 YLCEAKNGIG 85

Second Ig domain of the neural cell adhesion molecule contactin-2, and similar domains; The members here are composed of the second Ig domain of the neural cell adhesion molecule contactin-2. Contactins are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. Contactin-2 (also called TAG-1, axonin-1) facilitates cell adhesion by homophilic binding between molecules in apposed membranes. The first four Ig domains form the intermolecular binding fragment which arranges as a compact U-shaped module by contacts between Ig domains 1 and 4, and domains 2 and 3. It has been proposed that a linear zipper-like array forms, from contactin-2 molecules alternatively provided by the two apposed membranes.

Pssm-ID: 409392 Cd Length: 88 Bit Score: 42.17 E-value: 1.25e-04

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 2217265369  142 DPVVVQEGAPLTLQCNPPPGLPSPVIFWMSSSMEP-ITQDKR--VSQgHNGDLYFSNVMLQDMqTDYSCNARFH 212
Cdd:cd05727      3 DEVKVKEGWGVVLFCDPPPHYPDLSYRWLLNEFPNfIPEDGRrfVSQ-TNGNLYIAKVEASDR-GNYSCFVSSP 74

Second immunoglobulin (Ig)-like domain of fibroblast growth factor (FGF) receptor, and similar domains; member of the I-set of IgSF domains; The members here are composed of the second immunoglobulin (Ig)-like domain of fibroblast growth factor (FGF) receptor. FGF receptors bind FGF signaling polypeptides. FGFs participate in multiple processes such as morphogenesis, development, and angiogenesis. FGFs bind to four FGF receptor tyrosine kinases (FGFR1, FGFR2, FGFR3, FGFR4). Receptor diversity is controlled by alternative splicing producing splice variants with different ligand binding characteristics and different expression patterns. FGFRs have an extracellular region comprised of three Ig-like domains, a single transmembrane helix, and an intracellular tyrosine kinase domain. Ligand binding and specificity reside in the Ig-like domains 2 and 3, and the linker region that connects these two. FGFR activation and signaling depend on FGF-induced dimerization, a process involving cell surface heparin or heparin sulfate proteoglycans. This group also contains fibroblast growth factor (FGF) receptor like-1(FGFRL1). FGFRL1 does not have a protein tyrosine kinase domain at its C-terminus; neither does its cytoplasmic domain appear to interact with a signaling partner. It has been suggested that FGFRL1 may not have any direct signaling function, but instead acts as a decoy receptor trapping FGFs and preventing them from binding other receptors.

Pssm-ID: 409393 [Multi-domain] Cd Length: 95 Bit Score: 42.21 E-value: 1.28e-04

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  331 PYWLDEPK---NLILAP-GEDGRLVCRANGNPKPTVQWMVNGEPL---QSAPPNPNREvAGDTIIFRDTQISSRAVYQCN 403
Cdd:cd05729      1 PRFTDTEKmeeREHALPaANKVRLECGAGGNPMPNITWLKDGKEFkkeHRIGGTKVEE-KGWSLIIERAIPRDKGKYTCI 79


                   ....*.
gi 2217265369  404 TSNEHG 409
Cdd:cd05729     80 VENEYG 85

Second immunoglobulin (Ig)-like domain of protein tyrosine kinase (PTK) 7; The members here are composed of the second immunoglobulin (Ig)-like domain in protein tyrosine kinase (PTK) 7, also known as CCK4. PTK7 is a subfamily of the receptor protein tyrosine kinase family, and is referred to as an RPTK-like molecule. RPTKs transduce extracellular signals across the cell membrane and play important roles in regulating cell proliferation, migration, and differentiation. PTK7 is organized as an extracellular portion having seven Ig-like domains, a single transmembrane region, and a cytoplasmic tyrosine kinase-like domain. PTK7 is considered a pseudokinase as it has several unusual residues in some of the highly conserved tyrosine kinase (TK) motifs; it is predicted to lack TK activity. PTK7 may function as a cell-adhesion molecule. PTK7 mRNA is expressed at high levels in placenta, melanocytes, liver, lung, pancreas, and kidney. PTK7 is overexpressed in several cancers, including melanoma and colon cancer lines.

Pssm-ID: 409417 Cd Length: 95 Bit Score: 42.22 E-value: 1.29e-04

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 2217265369  248 SSQMVLRgmdllleCIASGVPTPDIAWYKKGGDLPSDKAKFENFNKALRIT--NVSEEDSGEYFCLASNKMGSI 319
Cdd:cd05760     16 SSRVTLR-------CHIDGHPRPTYQWFRDGTPLSDGQGNYSVSSKERTLTlrSAGPDDSGLYYCCAHNAFGSV 82

Fourth immunoglobulin (Ig)-like domain of NrCAM (NgCAM-related cell adhesion molecule); The members here are composed of the fourth immunoglobulin (Ig)-like domain of NrCAM (NgCAM-related cell adhesion molecule). NrCAM belongs to the L1 subfamily of cell adhesion molecules (CAMs) and is comprised of an extracellular region having six IG-like domains and five fibronectin type III domains, a transmembrane region, and an intracellular domain. NrCAM is primarily expressed in the nervous system.

Pssm-ID: 409454 Cd Length: 89 Bit Score: 42.28 E-value: 1.29e-04

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 2217265369   51 DNILIeCEAKGNPAPSFHWTRNSRFFNIAkdPRVSMRRRSGTLVIdfrSGGRPEEYEGEYQCFARNKFGTALSN 124
Cdd:cd05868     16 DGTLI-CRANGNPKPSISWLTNGVPIEIA--PTDPSRKVDGDTII---FSKVQERSSAVYQCNASNEYGYLLAN 83

First immunoglobulin (Ig) domain of contactin-5; member of the I-set of Ig superfamily domains; The members here are composed of the first immunoglobulin (Ig) domain of the neural cell adhesion molecule contactin-5. Contactins are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains, anchored to the membrane by glycosylphosphatidylinositol. The different contactins show different expression patterns in the central nervous system. In rats, a lack of contactin-5 (NB-2) results in an impairment of the neuronal activity in the auditory system. Contactin-5 is expressed specifically in the postnatal nervous system, peaking at about 3 weeks postnatal. Contactin-5 is highly expressed in the adult human brain in the occipital lobe and in the amygdala; lower levels of expression have been detected in the corpus callosum, caudate nucleus, and spinal cord. This group belongs to the I-set of IgSF domains.

Pssm-ID: 409435 Cd Length: 96 Bit Score: 42.24 E-value: 1.33e-04

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  444 LDCPFFGSPIPTLRWFKNGQGSNLDGGNYHVYENGSLEIKMIRK-EDQGIYTCVATNILG 502
Cdd:cd05848     24 LNCEARGNPVPTYRWLRNGTEIDTESDYRYSLIDGNLIISNPSEvKDSGRYQCLATNSIG 83

First immunoglobulin (Ig)-like constant domain in Robo (roundabout) receptors, and similar domains; The members here are composed of the first immunoglobulin (Ig)-like domain in Roundabout (Robo) receptors. Robo receptors play a role in the development of the central nervous system (CNS), and are receptors of Slit protein. Slit is a repellant secreted by the neural cells in the midline. Slit acts through Robo to prevent most neurons from crossing the midline from either side. Three mammalian Robo homologs (Robo1, Robo2, and Robo3), and three mammalian Slit homologs (Slit1, Slit2, Slit3), have been identified. Commissural axons, which cross the midline, express low levels of Robo; longitudinal axons, which avoid the midline, express high levels of Robo. Robo1, Robo2, and Robo3 are expressed by commissural neurons in the vertebrate spinal cord and Slit1, Slit2,and Slit3 are expressed at the ventral midline. Robo3 is a divergent member of the Robo family which instead of being a positive regulator of Slit responsiveness, antagonizes Slit responsiveness in precrossing axons. The Slit-Robo interaction is mediated by the second leucine-rich repeat (LRR) domain of Slit and the two N-terminal Ig domains of Robo, Ig1 and Ig2. The primary Robo binding site for Slit2 has been shown by surface plasmon resonance experiments and mutational analysis to be is the Ig1 domain, while the Ig2 domain has been proposed to harbor a weak secondary binding site.

Pssm-ID: 409490 [Multi-domain] Cd Length: 99 Bit Score: 42.15 E-value: 1.35e-04

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  248 SSQMVLRGMDLLLECIASGVPTPDIAWYKKGGDLPSDKAKFENFNKAL--------RITN--VSEEDSGEYFCLASNKMG 317
Cdd:cd07693      8 SDLIVSKGDPATLNCKAEGRPTPTIQWLKNGQPLETDKDDPRSHRIVLpsgslfflRVVHgrKGRSDEGVYVCVAHNSLG 87


                   ...
gi 2217265369  318 SIR 320
Cdd:cd07693     88 EAV 90

Third immunoglobulin (Ig)-like domain of peroxidasin; The members here are composed of the third immunoglobulin (Ig)-like domain in peroxidasin. Peroxidasin has a peroxidase domain and interacting extracellular motifs containing four Ig-like domains. It has been suggested that peroxidasin is secreted and has functions related to the stabilization of the extracellular matrix. It may play a part in various other important processes such as removal and destruction of cells which have undergone programmed cell death and protection of the organism against non-self.

Pssm-ID: 143222 [Multi-domain] Cd Length: 74 Bit Score: 41.46 E-value: 1.55e-04

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 2217265369  446 CPFFGSPIPTLRWFKNGQGSNLDGgNYHVYENGSLEIKMIRKEDQGIYTCVATNILGKAENQVRLEV 512
Cdd:cd05745      9 CEAQGYPQPVIAWTKGGSQLSVDR-RHLVLSSGTLRISRVALHDQGQYECQAVNIVGSQRTVAQLTV 74

First immunoglobulin (Ig) domain of contactin-1; member of the I-set of Ig superfamily domains; The members here are composed of the first immunoglobulin (Ig) domain of the neural cell adhesion molecule contactin-1. Contactins are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. Contactin-1 is differentially expressed in tumor tissues and may, through a RhoA mechanism, facilitate invasion and metastasis of human lung adenocarcinoma. This group belongs to the I-set of IgSF domains.

Pssm-ID: 409436 [Multi-domain] Cd Length: 95 Bit Score: 41.86 E-value: 1.70e-04

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 2217265369   55 IECEAKGNPAPSFHWTRNSRFFNIAKDpRVSMrrRSGTLVIDfrsggRPEEYE--GEYQCFARNKFGTALSNRIRL 128
Cdd:cd05849     24 VNCRARANPFPIYKWRKNNLDIDLTND-RYSM--VGGNLVIN-----NPDKYKdaGRYVCIVSNIYGKVRSREATL 91

First immunoglobulin (Ig) domain of contactin-1; member of the I-set of Ig superfamily domains; The members here are composed of the first immunoglobulin (Ig) domain of the neural cell adhesion molecule contactin-1. Contactins are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. Contactin-1 is differentially expressed in tumor tissues and may, through a RhoA mechanism, facilitate invasion and metastasis of human lung adenocarcinoma. This group belongs to the I-set of IgSF domains.

Pssm-ID: 409436 [Multi-domain] Cd Length: 95 Bit Score: 41.86 E-value: 1.73e-04

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|....
gi 2217265369  260 LECIASGVPTPDIAWYKKGGDLPSDKAKFENFNKALRITNVSE-EDSGEYFCLASNKMGSIRHT 322
Cdd:cd05849     24 VNCRARANPFPIYKWRKNNLDIDLTNDRYSMVGGNLVINNPDKyKDAGRYVCIVSNIYGKVRSR 87

Second immunoglobulin (Ig)-like domain in Robo (roundabout) receptors; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the second immunoglobulin (Ig)-like domain in Robo (roundabout) receptors. Robo receptors play a role in the development of the central nervous system (CNS), and are receptors of the Slit protein. Slit is a repellant secreted by the neural cells in the midline. Slit acts through Robo to prevent most neurons from crossing the midline from either side. Three mammalian Robo homologs (Robo1, Robo2, and Robo3), and three mammalian Slit homologs (Slit-1,Slit-2, Slit-3), have been identified. Commissural axons, which cross the midline, express low levels of Robo; longitudinal axons, which avoid the midline, express high levels of Robo. Robo1, Robo2, and Robo3 are expressed by commissural neurons in the vertebrate spinal cord and Slit-1, Slit-2, Slit-3 are expressed at the ventral midline. Robo-3 is a divergent member of the Robo family which instead of being a positive regulator of Slit responsiveness, antagonizes Slit responsiveness in precrossing axons. The Slit-Robo interaction is mediated by the second leucine-rich repeat (LRR) domain of Slit and the two N-terminal Ig domains of Robo, Ig1 and Ig2. The primary Robo binding site for Slit-2 has been shown by surface plasmon resonance experiments and mutational analysis to be the Ig1 domain, while the Ig2 domain has been proposed to harbor a weak secondary binding site. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409389 [Multi-domain] Cd Length: 87 Bit Score: 41.62 E-value: 1.78e-04

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 2217265369  144 VVVQEGAPLTLQCNPPPGLPSPVIFWMSSSMEPITQDKRVSQGHNGDLYFSNVMLQDMQTdYSCNA 209
Cdd:cd05724      7 TQVAVGEMAVLECSPPRGHPEPTVSWRKDGQPLNLDNERVRIVDDGNLLIAEARKSDEGT-YKCVA 71

Immunoglobulin (Ig)-like domain of Down Syndrome Cell Adhesion molecule (DSCAM); The members here are composed of the immunoglobulin (Ig)-like domain of Down Syndrome Cell Adhesion molecule (DSCAM). DSCAM is a cell adhesion molecule expressed largely in the developing nervous system. The gene encoding DSCAM is located at human chromosome 21q22, the locus associated with the intellectual disability phenotype of Down Syndrome. DSCAM is predicted to be the largest member of the IG superfamily. It has been demonstrated that DSCAM can mediate cation-independent homophilic intercellular adhesion.

Pssm-ID: 409397 [Multi-domain] Cd Length: 97 Bit Score: 41.71 E-value: 1.82e-04

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  423 PPR-MLSPRNQliRVILYNRTRLDCPFFGSPIPTLRW-FKNGQGSN------LDGGNYHVYENGSLEIKMIRKEDQGIYT 494
Cdd:cd05734      1 PPRfVVQPNDQ--DGIYGKAVVLNCSADGYPPPTIVWkHSKGSGVPqfqhivPLNGRIQLLSNGSLLIKHVLEEDSGYYL 78


                   ....*...
gi 2217265369  495 CVATNILG 502
Cdd:cd05734     79 CKVSNDVG 86

Second immunoglobulin (Ig)-like domain in Robo (roundabout) receptors; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the second immunoglobulin (Ig)-like domain in Robo (roundabout) receptors. Robo receptors play a role in the development of the central nervous system (CNS), and are receptors of the Slit protein. Slit is a repellant secreted by the neural cells in the midline. Slit acts through Robo to prevent most neurons from crossing the midline from either side. Three mammalian Robo homologs (Robo1, Robo2, and Robo3), and three mammalian Slit homologs (Slit-1,Slit-2, Slit-3), have been identified. Commissural axons, which cross the midline, express low levels of Robo; longitudinal axons, which avoid the midline, express high levels of Robo. Robo1, Robo2, and Robo3 are expressed by commissural neurons in the vertebrate spinal cord and Slit-1, Slit-2, Slit-3 are expressed at the ventral midline. Robo-3 is a divergent member of the Robo family which instead of being a positive regulator of Slit responsiveness, antagonizes Slit responsiveness in precrossing axons. The Slit-Robo interaction is mediated by the second leucine-rich repeat (LRR) domain of Slit and the two N-terminal Ig domains of Robo, Ig1 and Ig2. The primary Robo binding site for Slit-2 has been shown by surface plasmon resonance experiments and mutational analysis to be the Ig1 domain, while the Ig2 domain has been proposed to harbor a weak secondary binding site. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409389 [Multi-domain] Cd Length: 87 Bit Score: 41.62 E-value: 1.88e-04

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  522 PEDQVARRGTTVQLEC---RVKHDPslklTVSWLKDDEPLYIGNRMKK--EDDSLTIFGVAERDQGSYTCVAS-TELDQD 595
Cdd:cd05724      4 PSDTQVAVGEMAVLECsppRGHPEP----TVSWRKDGQPLNLDNERVRivDDGNLLIAEARKSDEGTYKCVATnMVGERE 79


                   ....*...
gi 2217265369  596 LAKAYLTV 603
Cdd:cd05724     80 SRAARLSV 87

C-terminal immunoglobulin (Ig)-like domain of M-protein; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the C-terminal immunoglobulin (Ig)-like domain of M-protein (also known as myomesin-2). M-protein is a structural protein localized to the M-band, a transverse structure in the center of the sarcomere, and is a candidate for M-band bridges. M-protein is modular consisting mainly of repetitive IG-like and fibronectin type III (FnIII) domains and has a muscle-type specific expression pattern. M-protein is present in fast fibers.

Pssm-ID: 143299 Cd Length: 92 Bit Score: 41.82 E-value: 1.92e-04

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  252 VLRGMDLLLECIASGVPTPDIAWYKKGGDL-PSD-------KAKFenfnKALRITNVSEEDSGEYFCLASNKMGSIRHTI 323
Cdd:cd05891     13 IMEGKTLNLTCTVFGNPDPEVIWFKNDQDIeLSEhysvkleQGKY----ASLTIKGVTSEDSGKYSINVKNKYGGETVDV 88


                   ....
gi 2217265369  324 SVRV 327
Cdd:cd05891     89 TVSV 92

Fourth immunoglobulin (Ig)-like domain in neogenin, and similar domains; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the fourth immunoglobulin (Ig)-like domain in neogenin and related proteins. Neogenin is a cell surface protein which is expressed in the developing nervous system of vertebrate embryos in the growing nerve cells. It is also expressed in other embryonic tissues, and may play a general role in developmental processes such as cell migration, cell-cell recognition, and tissue growth regulation. Included in this group is the tumor suppressor protein DCC which is deleted in colorectal carcinoma. DCC and neogenin each have four Ig-like domains followed by six fibronectin type III domains, a transmembrane domain, and an intracellular domain. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409388 Cd Length: 84 Bit Score: 41.41 E-value: 1.93e-04

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369   31 LTQPPTITKQSAKDhivdprdnILIECEAKGNPAPSFHWTRN------SRFFNIAKDPrvsmrrrsgtlviDFRSGGRPE 104
Cdd:cd05723      1 LKKPSNIYAHESMD--------IVFECEVTGKPTPTVKWVKNgdvvipSDYFKIVKEH-------------NLQVLGLVK 59

                           90
                   ....*....|....*....
gi 2217265369  105 EYEGEYQCFARNKFGTALS 123
Cdd:cd05723     60 SDEGFYQCIAENDVGNAQA 78

Third immunoglobulin (Ig)-like domain of Neural Cell Adhesion Molecule 1 (NCAM-1); member of the I-set of IgSF domains; The members here are composed of the third immunoglobulin (Ig)-like domain of Neural Cell Adhesion Molecule (NCAM-1). NCAM plays important roles in the development and regeneration of the central nervous system, in synaptogenesis and neural migration. NCAM mediates cell-cell and cell-substratum recognition and adhesion via homophilic (NCAM-NCAM), and heterophilic (NCAM-non-NCAM), interactions. NCAM is expressed as three major isoforms having different intracellular extensions. The extracellular portion of NCAM has five N-terminal Ig-like domains and two fibronectin type III domains. The double zipper adhesion complex model for NCAM homophilic binding involves Ig1, Ig2, and Ig3. By this model, Ig1 and Ig2 mediate dimerization of NCAM molecules situated on the same cell surface (cis interactions), and Ig3 domains mediate interactions between NCAM molecules expressed on the surface of opposing cells (trans interactions) through binding to the Ig1 and Ig2 domains. The adhesive ability of NCAM is modulated by the addition of polysialic acid chains to the fifth Ig-like domain.

Pssm-ID: 143207 [Multi-domain] Cd Length: 95 Bit Score: 41.84 E-value: 1.94e-04

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 2217265369  345 GEDGRLVCRANGNPKPTVQWMVNGEPLQSAPPNPNREVAGDTIIFRDTQISSRAVYQCNTSNEHG 409
Cdd:cd05730     18 GQSVTLACDADGFPEPTMTWTKDGEPIESGEEKYSFNEDGSEMTILDVDKLDEAEYTCIAENKAG 82

Immunoglobulin (Ig)-like domain of vascular endothelial growth factor receptor 2 (VEGFR-2); member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the immunoglobulin (Ig)-like domain of vascular endothelial growth factor receptor 2 (VEGFR-2). The VEGFRs have an extracellular component with seven Ig-like domains, a transmembrane segment, and an intracellular tyrosine kinase domain interrupted by a kinase-insert domain. VEGFRs bind VEGFs with high affinity at the Ig-like domains. VEGFR-2 (KDR/Flk-1) is a major mediator of the mitogenic, angiogenic and microvascular permeability-enhancing effects of VEGF-A; VEGF-A is important to the growth and maintenance of vascular endothelial cells and to the development of new blood- and lymphatic-vessels in physiological and pathological states. VEGF-A also interacts with VEGFR-1, which it binds more strongly than VEGFR-2. VEGFR-1 and VEGFR-2 may mediate a chemotactic and a survival signal in hematopoietic stem cells or leukemia cells. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409450 Cd Length: 89 Bit Score: 41.45 E-value: 2.03e-04

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 2217265369  432 QLIRVILYNRTRLDCPFFGSPIPTLRWFKNGQGSNldgGNYHVYENGSLEIKMIRKEDQGIYTCVATNILGKAE 505
Cdd:cd05864     10 SLVEAKVGERVRIPVKYLGYPPPEIKWYKNGIPIE---SNHTIKAGHVLTIMEVTEKDAGNYTVVLTNPISKEK 80

Second immunoglobulin (Ig)-like domain in Robo (roundabout) receptors; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the second immunoglobulin (Ig)-like domain in Robo (roundabout) receptors. Robo receptors play a role in the development of the central nervous system (CNS), and are receptors of the Slit protein. Slit is a repellant secreted by the neural cells in the midline. Slit acts through Robo to prevent most neurons from crossing the midline from either side. Three mammalian Robo homologs (Robo1, Robo2, and Robo3), and three mammalian Slit homologs (Slit-1,Slit-2, Slit-3), have been identified. Commissural axons, which cross the midline, express low levels of Robo; longitudinal axons, which avoid the midline, express high levels of Robo. Robo1, Robo2, and Robo3 are expressed by commissural neurons in the vertebrate spinal cord and Slit-1, Slit-2, Slit-3 are expressed at the ventral midline. Robo-3 is a divergent member of the Robo family which instead of being a positive regulator of Slit responsiveness, antagonizes Slit responsiveness in precrossing axons. The Slit-Robo interaction is mediated by the second leucine-rich repeat (LRR) domain of Slit and the two N-terminal Ig domains of Robo, Ig1 and Ig2. The primary Robo binding site for Slit-2 has been shown by surface plasmon resonance experiments and mutational analysis to be the Ig1 domain, while the Ig2 domain has been proposed to harbor a weak secondary binding site. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409389 [Multi-domain] Cd Length: 87 Bit Score: 41.23 E-value: 2.06e-04

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  336 EPKNLILAPGEDGRLVCRA-NGNPKPTVQWMVNGEPLQSAPPnPNREVAGDTIIFRDTQISSRAVYQCNTSNEHGYLLAN 414
Cdd:cd05724      3 EPSDTQVAVGEMAVLECSPpRGHPEPTVSWRKDGQPLNLDNE-RVRIVDDGNLLIAEARKSDEGTYKCVATNMVGERESR 81


                   ....*.
gi 2217265369  415 -AFVSV 419
Cdd:cd05724     82 aARLSV 87

Second immunoglobulin (Ig)-like domain in Robo (roundabout) receptors; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the second immunoglobulin (Ig)-like domain in Robo (roundabout) receptors. Robo receptors play a role in the development of the central nervous system (CNS), and are receptors of the Slit protein. Slit is a repellant secreted by the neural cells in the midline. Slit acts through Robo to prevent most neurons from crossing the midline from either side. Three mammalian Robo homologs (Robo1, Robo2, and Robo3), and three mammalian Slit homologs (Slit-1,Slit-2, Slit-3), have been identified. Commissural axons, which cross the midline, express low levels of Robo; longitudinal axons, which avoid the midline, express high levels of Robo. Robo1, Robo2, and Robo3 are expressed by commissural neurons in the vertebrate spinal cord and Slit-1, Slit-2, Slit-3 are expressed at the ventral midline. Robo-3 is a divergent member of the Robo family which instead of being a positive regulator of Slit responsiveness, antagonizes Slit responsiveness in precrossing axons. The Slit-Robo interaction is mediated by the second leucine-rich repeat (LRR) domain of Slit and the two N-terminal Ig domains of Robo, Ig1 and Ig2. The primary Robo binding site for Slit-2 has been shown by surface plasmon resonance experiments and mutational analysis to be the Ig1 domain, while the Ig2 domain has been proposed to harbor a weak secondary binding site. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409389 [Multi-domain] Cd Length: 87 Bit Score: 41.23 E-value: 2.12e-04

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 2217265369  248 SSQMVLRGMDLLLECIAS-GVPTPDIAWYKKGGDLPSDKAKFENFNKA-LRITNVSEEDSGEYFCLASNKMG 317
Cdd:cd05724      5 SDTQVAVGEMAVLECSPPrGHPEPTVSWRKDGQPLNLDNERVRIVDDGnLLIAEARKSDEGTYKCVATNMVG 76

Immunoglobulin variable domain (IgV); The members here are composed of the immunoglobulin variable domain (IgV). The IgV family contains the standard Ig superfamily V-set AGFCC'C"/DEB domain topology, and are components of immunoglobulin (Ig) and T cell receptors. The basic structure of Ig molecules is a tetramer of two light chains and two heavy chains linked by disulfide bonds. In Ig, each chain is composed of one variable domain (IgV) and one or more constant domains (IgC); these names reflect the fact that the variability in sequences is higher in the variable domain than in the constant domain. Within the variable domain, there are regions of even more variability called the hypervariable or complementarity-determining regions (CDRs) which are responsible for antigen binding. A predominant feature of most Ig domains is the disulfide bridge connecting 2 beta-sheets with a tryptophan residue packed against the disulfide bond. Ig superfamily (IgSF) domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Typically, the V-set domains have A, B, E and, D strands in one sheet and A', G, F, C, C', and C" strands in the other.

Pssm-ID: 409355 [Multi-domain] Cd Length: 111 Bit Score: 41.94 E-value: 2.13e-04

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  248 SSQMVLRGMDLLLECIASG-VPTPDIAWYK----------------KGGDLPSDKAKFE-NFNKA----LRITNVSEEDS 305
Cdd:cd00099      6 RSLSVQEGESVTLSCEVSSsFSSTYIYWYRqkpgqgpefliylsssKGKTKGGVPGRFSgSRDGTssfsLTISNLQPEDS 85

                           90
                   ....*....|..
gi 2217265369  306 GEYFCLASNKMG 317
Cdd:cd00099     86 GTYYCAVSESGG 97

Fourth immunoglobulin (Ig)-like domain of the L1 cell adhesion molecule (CAM); The members here are composed of the fourth immunoglobulin (Ig)-like domain of the L1 cell adhesion molecule (CAM). L1 is comprised of an extracellular region having six Ig-like domains and five fibronectin type III domains, a transmembrane region, and an intracellular domain. L1 is primarily expressed in the nervous system and is involved in its development and function. L1 is associated with an X-linked recessive disorder, X-linked hydrocephalus, MASA syndrome, and spastic paraplegia type 1, that involves abnormalities of axonal growth. This group also contains the chicken neuron-glia cell adhesion molecule, Ng-CAM.

Pssm-ID: 409453 [Multi-domain] Cd Length: 89 Bit Score: 41.42 E-value: 2.18e-04

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369   43 KDHIVDPRDNILIECEAKGNPAPSFHWTRNS-RFFNIAKDPRvsMRRRSGTLVIdfrSGGRPEEyEGEYQCFARNKFGTA 121
Cdd:cd05867      7 QSHLYGPGETARLDCQVEGIPTPNITWSINGaPIEGTDPDPR--RHVSSGALIL---TDVQPSD-TAVYQCEARNRHGNL 80


                   ...
gi 2217265369  122 LSN 124
Cdd:cd05867     81 LAN 83

Third immunoglobulin (Ig)-like domain of the L1 cell adhesion molecule (CAM), and similar domains; The members here are composed of the third immunoglobulin (Ig)-like domain of the L1 cell adhesion molecule (CAM). L1 belongs to the L1 subfamily of cell adhesion molecules (CAMs) and is comprised of an extracellular region having six Ig-like domains and five fibronectin type III domains, a transmembrane region and an intracellular domain. L1 is primarily expressed in the nervous system and is involved in its development and function. L1 is associated with an X-linked recessive disorder, X-linked hydrocephalus, MASA syndrome, and spastic paraplegia type 1, that involves abnormalities of axonal growth. This group also contains the chicken neuron-glia cell adhesion molecule, Ng-CAM and human neurofascin.

Pssm-ID: 409394 [Multi-domain] Cd Length: 83 Bit Score: 41.24 E-value: 2.23e-04

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 2217265369  525 QVARRGTTVQLECRVKHDPSLKltVSWLKDDEPLYiGNRMKKED--DSLTIFGVAERDQGSYTCVAS 589
Cdd:cd05731      5 TMVLRGGVLLLECIAEGLPTPD--IRWIKLGGELP-KGRTKFENfnKTLKIENVSEADSGEYQCTAS 68

Fifth immunoglobulin domain of the Drosophila melanogaster Dscam protein, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the fifth immunoglobulin domain of the Drosophila melanogaster Down syndrome cell adhesion molecule (DSCAM) protein and similar proteins. Down syndrome cell adhesion molecule (DSCAM) is a cell adhesion molecule that plays critical roles in neural development, including axon guidance and branching, axon target recognition, self-avoidance and synaptic formation. DSCAM belongs to the immunoglobulin superfamily and contributes to defects in the central nervous system in Down syndrome patients. Vertebrate DSCAMs differ from Drosophila Dscam1 in that they lack the extensive alternative splicing that occurs in the insect gene. Drosophila melanogaster Dscam has 38,016 isoforms generated by the alternative splicing of four variable exon clusters, which allows every neuron in the fly to display a distinctive set of Dscam proteins on its cell surface. Drosophila Dscam1 is a cell-surface protein that plays important roles in neural development and axon tiling of neurons. It is shown that thousands of isoforms bind themselves through specific homophilic (self-binding) interactions, a process which mediates cellular self-recognition. Drosophila Dscam2 is also alternatively spliced and plays a key role in the development of two visual system neurons, monopolar cells L1 and L2. This group is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand.

Pssm-ID: 409550 [Multi-domain] Cd Length: 89 Bit Score: 41.40 E-value: 2.30e-04

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  252 VLRGMDLLLECIASGVPTPDIAWYKKGGDLPSDKAK--FEnfNKALRITNV-SEEDSGEYFCLASNKMG-SIRHTISVRV 327
Cdd:cd20958     12 AVAGQTLRLHCPVAGYPISSITWEKDGRRLPLNHRQrvFP--NGTLVIENVqRSSDEGEYTCTARNQQGqSASRSVFVKV 89

Fifth immunoglobulin (Ig)-like domain of the carcinoembryonic antigen (CEA) related cell adhesion molecule 5 (CEACAM5) and similar domains; member of the C2-set IgSF domains; The members here are composed of the fifth immunoglobulin (Ig)-like domain of the carcinoembryonic antigen (CEA) related cell adhesion molecule 5 (CEACAM5) and similar domains. The CEA family is a group of anchored or secreted glycoproteins, expressed by epithelial cells, leukocytes, endothelial cells and placenta. The CEA family is divided into the CEACAM and pregnancy-specific glycoprotein (PSG) subfamilies. Carcinoembryonic antigen-related cell adhesion molecule 5 (CEACAM5), also known as CD66e (Cluster of Differentiation 66e), is a cell surface glycoprotein that plays a role in cell adhesion, intracellular signaling and tumor progression. Diseases associated with CEACAM5 include lung cancer and rectum cancer. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. This group belongs to the C2-set of IgSF domains, having A, B, and E strands in one beta-sheet and A', G, F, C' in the other. Unlike other Ig domain sets, the C2-set lacks the D strand.

Pssm-ID: 409540 Cd Length: 76 Bit Score: 40.94 E-value: 2.31e-04

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 2217265369  253 LRGMDLLLECIASGVPTPDIAWYKKGgdlpsdkaKFENFNKALRITNVSEEDSGEYFCLASNKMGS 318
Cdd:cd20948      8 LSGENLNLSCHAASNPPAQYSWTING--------TFQTSSQELFLPAITENNEGTYTCSAHNSLTG 65

Second immunoglobulin (Ig)-like domain of interleukin-1 receptor (IL1R), and similar domains; The members here are composed of the second immunoglobulin (Ig)-like domain of interleukin-1 receptor (IL1R). IL-1 alpha and IL-1 beta are cytokines which participate in the regulation of inflammation, immune responses, and hematopoiesis. These cytokines bind to the IL-1 receptor type 1 (IL1R1), which is activated on additional association with interleukin-1 receptor accessory protein (IL1RAP). IL-1 also binds a second receptor designated type II (IL1R2). Mature IL1R1 consists of three IG-like domains, a transmembrane domain, and a large cytoplasmic domain. Mature IL1R2 is organized similarly except that it has a short cytoplasmic domain. The latter does not initiate signal transduction. A naturally occurring cytokine IL-1RA (IL-1 receptor antagonist) is widely expressed and binds to IL-1 receptors, inhibiting the binding of IL-1 alpha and IL-1 beta. This group also contains ILIR-like 1 (IL1R1L) which maps to the same chromosomal location as IL1R1 and IL1R2.

Pssm-ID: 409586 Cd Length: 94 Bit Score: 41.30 E-value: 2.45e-04

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|...
gi 2217265369  270 PDIAWYKKGGDLPSDKAKFENFNKALRITNVSEEDSGEYFCLAS----NKMGSIRHTISVRVK 328
Cdd:cd20994     31 PKVQWYKDCKPLLLDDKRFAGLESDLLIFNVTVQDQGNYTCHTSytymGKQYNISRTISLIVL 93

Immunoglobulin I-set domain of the Leucine-rich repeat and immunoglobin-like domain-containing protein 1 (Lingo-1); The members here are composed of the immunoglobulin I-set (IgI) domain of the Leucine-rich repeat and immunoglobin-like domain-containing protein 1 (Lingo-1). Human Lingo-1 is a central nervous system-specific transmembrane glycoprotein also known as LERN-1, which functions as a negative regulator of neuronal survival, axonal regeneration, and oligodendrocyte differentiation and myelination. Lingo-1 is a key component of the Nogo receptor signaling complex (RTN4R/NGFR) in RhoA activation responsible for some inhibition of axonal regeneration by myelin-associated factors. The ligand-binding ectodomain of human Lingo-1 contains a bimodular, kinked structure composed of leucine-rich repeat (LRR) and immunoglobulin (Ig)-like modules. Diseases associated with Lingo-1 include mental retardation, autosomal recessive 64 and essential tremor. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structure of the Lingo-1 lacks this strand and thus it belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409561 Cd Length: 92 Bit Score: 41.22 E-value: 2.55e-04

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  515 PTRIYRMPEDQV-ARRGTTVQLECRVKHDPSLklTVSWLKDDEPLYIGnrmkKEDDSLTIF--GVAE------RDQGSYT 585
Cdd:cd20969      1 RAAIRDRKAQQVfVDEGHTVQFVCRADGDPPP--AILWLSPRKHLVSA----KSNGRLTVFpdGTLEvryaqvQDNGTYL 74

                           90
                   ....*....|....*...
gi 2217265369  586 CVASTELDQDLAKAYLTV 603
Cdd:cd20969     75 CIAANAGGNDSMPAHLHV 92

First immunoglobulin (Ig) domain of contactin-2; member of the I-set of Ig superfamily domains; The members here are composed of the first immunoglobulin (Ig) domain of the neural cell adhesion molecule contactin-2-like. Contactins are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. Contactin-2 (TAG-1, axonin-1) facilitates cell adhesion by homophilic binding between molecules in apposed membranes. It may play a part in the neuronal processes of neurite outgrowth, axon guidance and fasciculation, and neuronal migration. The first four Ig domains form the intermolecular binding fragment, which arranges as a compact U-shaped module by contacts between IG domains 1 and 4, and domains 2 and 3. The different contactins show different expression patterns in the central nervous system. During development and in adulthood, contactin-2 is transiently expressed in subsets of central and peripheral neurons. Contactin-2 is also expressed in retinal amacrine cells in the developing chick retina, corresponding to the period of formation and maturation of AC processes. This group belongs to the I-set of IgSF domains.

Pssm-ID: 409437 [Multi-domain] Cd Length: 97 Bit Score: 41.45 E-value: 2.61e-04

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369   49 PRDNILIECEAKGNPAPSFHWTRNSRFFNIAKDPRvsMRRRSGTLVIDFRSGGRPeeyEGEYQCFARNKFGTALSNRIRL 128
Cdd:cd05850     19 AEEKVTLACRARASPPATYRWKMNGTELKMEPDSR--YRLVAGNLVISNPVKAKD---AGSYQCLASNRRGTVVSREASL 93


                   .
gi 2217265369  129 Q 129
Cdd:cd05850     94 R 94

Third immunoglobulin (Ig)-like domain of Neural Cell Adhesion Molecule 1 (NCAM-1); member of the I-set of IgSF domains; The members here are composed of the third immunoglobulin (Ig)-like domain of Neural Cell Adhesion Molecule (NCAM-1). NCAM plays important roles in the development and regeneration of the central nervous system, in synaptogenesis and neural migration. NCAM mediates cell-cell and cell-substratum recognition and adhesion via homophilic (NCAM-NCAM), and heterophilic (NCAM-non-NCAM), interactions. NCAM is expressed as three major isoforms having different intracellular extensions. The extracellular portion of NCAM has five N-terminal Ig-like domains and two fibronectin type III domains. The double zipper adhesion complex model for NCAM homophilic binding involves Ig1, Ig2, and Ig3. By this model, Ig1 and Ig2 mediate dimerization of NCAM molecules situated on the same cell surface (cis interactions), and Ig3 domains mediate interactions between NCAM molecules expressed on the surface of opposing cells (trans interactions) through binding to the Ig1 and Ig2 domains. The adhesive ability of NCAM is modulated by the addition of polysialic acid chains to the fifth Ig-like domain.

Pssm-ID: 143207 [Multi-domain] Cd Length: 95 Bit Score: 41.46 E-value: 2.70e-04

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  527 ARRGTTVQLECRVKHDPslKLTVSWLKDDEPLYIG-NRMKKEDDS--LTIFGVAERDQGSYTCVASTELDQDLAKAYLTV 603
Cdd:cd05730     15 ANLGQSVTLACDADGFP--EPTMTWTKDGEPIESGeEKYSFNEDGseMTILDVDKLDEAEYTCIAENKAGEQEAEIHLKV 92


                   ..
gi 2217265369  604 LA 605
Cdd:cd05730     93 FA 94

Immunoglobulin V-set domain; This domain is found in antibodies as well as neural protein P0 and CTL4 amongst others.

Pssm-ID: 462230 Cd Length: 109 Bit Score: 41.67 E-value: 2.89e-04

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  246 TASSQMVLRGMDLLLECIASG---VPTPDIAWYK---------------KGGDLPSDKAKFE------NFNKALRITNVS 301
Cdd:pfam07686    2 TPREVTVALGGSVTLPCTYSSsmsEASTSVYWYRqppgkgptfliayysNGSEEGVKKGRFSgrgdpsNGDGSLTIQNLT 81

                           90       100
                   ....*....|....*....|....*..
gi 2217265369  302 EEDSGEYFC-LASNKMGSIRHTISVRV 327
Cdd:pfam07686   82 LSDSGTYTCaVIPSGEGVFGKGTRLTV 108

Eighth immunoglobulin (Ig)-like domain of human myosin light-chain kinase (MLCK) and similar protein; member of the I-set of IgSF domains; The members here are composed of the eighth immunoglobulin (Ig)-like domain of human myosin light-chain kinase (MLCK) and similar proteins. Myosin light-chain kinase (MLCK) is a key regulator of different forms of cell motility involving actin and myosin II. Agonist stimulation of smooth muscle cells increases cytosolic Ca2+ which binds calmodulin. This Ca2+-calmodulin complex in turn binds to and activates MLCK. Activated MLCK leads to the phosphorylation of the 20 kDa myosin regulatory light chain (RLC) of myosin II and the stimulation of actin-activated myosin MgATPase activity. MLCK is widely present in vertebrate tissues; it phosphorylates the 20 kDa RLC of both smooth and nonmuscle myosin II. Phosphorylation leads to the activation of the myosin motor domain and altered structural properties of myosin II. In smooth muscle MLCK it is involved in initiating contraction. In nonmuscle cells, MLCK may participate in cell division and cell motility; it has been suggested MLCK plays a role in cardiomyocyte differentiation and contraction through regulation of nonmuscle myosin II.

Pssm-ID: 409419 Cd Length: 99 Bit Score: 41.48 E-value: 2.92e-04

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  515 PTRIYRMPEDQVARRGTTVQLECRVKHdpSLKLTVSWLKDDEPLYIGNRMKKED----DSLTIFGVAERDQGSYTCVAST 590
Cdd:cd05762      1 PPQIIQFPEDMKVRAGESVELFCKVTG--TQPITCTWMKFRKQIQEGEGIKIENtensSKLTITEGQQEHCGCYTLEVEN 78

                           90       100
                   ....*....|....*....|
gi 2217265369  591 ELDQDLAKAYLTVLaDQATP 610
Cdd:cd05762     79 KLGSRQAQVNLTVV-DKPDP 97

Second immunoglobulin (Ig)-like domain of a Follistatin-related protein 5, and similar domains; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the second immunoglobulin (Ig)-like domain found in human Follistatin-related protein 5 (FSTL5) and a follistatin-like molecule encoded by the CNS-related Mahya gene. Mahya genes have been retained in certain Bilaterian branches during evolution. They are conserved in Hymenoptera and Deuterostomes, but are absent from other metazoan species such as fruit fly and nematode. Mahya proteins are secretory, with a follistatin-like domain (Kazal-type serine/threonine protease inhibitor domain and EF-hand calcium-binding domain), two Ig-like domains, and a novel C-terminal domain. Mahya may be involved in learning and memory and in processing of sensory information in Hymenoptera and vertebrates. Follistatin is a secreted, multidomain protein that binds activins with high affinity and antagonizes their signaling.

Pssm-ID: 409399 [Multi-domain] Cd Length: 93 Bit Score: 41.09 E-value: 3.03e-04

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 2217265369  344 PGEDGRLVCRANGNPKPTVQWMVNGEPLQSAPPNPNREVA-GDTIIFRDTQISSRAVYQCNTSNEHG 409
Cdd:cd05736     14 PGVEASLRCHAEGIPLPRVQWLKNGMDINPKLSKQLTLIAnGSELHISNVRYEDTGAYTCIAKNEGG 80

Third immunoglobulin (Ig)-like domain of the L1 cell adhesion molecule (CAM); The members here are composed of the third immunoglobulin (Ig)-like domain of the L1 cell adhesion molecule (CAM). L1 belongs to the L1 subfamily of cell adhesion molecules (CAMs) and is comprised of an extracellular region having six Ig-like domains, five fibronectin type III domains, a transmembrane region and an intracellular domain. L1 is primarily expressed in the nervous system and is involved in its development and function. L1 is associated with an X-linked recessive disorder, X-linked hydrocephalus, MASA syndrome, or spastic paraplegia type 1, that involves abnormalities of axonal growth. This group also contains the chicken neuron-glia cell adhesion molecule, Ng-CAM.

Pssm-ID: 409460 [Multi-domain] Cd Length: 83 Bit Score: 40.66 E-value: 3.12e-04

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 2217265369   53 ILIECEAKGNPAPSFHWTRNSrffniakDP----RVSMRRRSGTLVIDfrsgGRPEEYEGEYQCFARNKFGTA 121
Cdd:cd05876     13 LVLECIAEGLPTPTVKWLRPS-------GPlppdRVKYQNHNKTLQLL----NVGESDDGEYVCLAENSLGSA 74

Immunoglobulin-like Ig0 domain of basigin-1 (BSG1) and similar proteins; The members here are composed of the immunoglobulin (Ig) domain of the collagenase stimulatory factor, basigin-1 (BSG1; also known as Cluster of Differentiation 147 (CD147) and Extracellular Matrix Metalloproteinase Inducer (EMMPRIN)) and similar proteins. CD147 is a transmembrane glycoprotein that belongs to the immunoglobulin superfamily. It is expressed in nearly all cells including platelets and fibroblasts and is involved in inflammatory diseases, and cancer progression. CD147 is highly expressed in several cancers and used as a prognostic marker. The two primary isoforms of CD147 that are related to cancer progression have been identified: CD147 Ig1-Ig2 (also called Basigin-2) that is ubiquitously expressed in most tissues and CD147 Ig0-Ig1-Ig2 (also called Basigin-1) that is retinal specific and implicated in retinoblastoma. Studies showed that CD147 Ig0 domain is a potent stimulator of interleukin-6 and suggest that the CD147 Ig0 dimer is the functional unit required for activity.

Pssm-ID: 409534 Cd Length: 116 Bit Score: 41.87 E-value: 3.29e-04

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  249 SQMVLRGMDLLLECIASGVPTPDIAWYKKGGDlPS-------DKAKFENFN----------KALRITNVSEEDSGEYFCL 311
Cdd:cd20940      9 SQQRLVGDSVELHCEAVGSPIPEIQWWFEGQE-PNeicsqlwDGARLDRVHinatyhqhatSTISIDNLTEEDTGTYECR 87

                           90       100       110
                   ....*....|....*....|....*....|.
gi 2217265369  312 ASNKMGSIRHTISVRVKaapyWLDEPKNLIL 342
Cdd:cd20940     88 ASNDPDRNHLTRAPKVK----WIRSQANVLV 114

Fifth domain (immunoglobulin-like) of Trk receptors TrkA, TrkB, and TrkC; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the fifth domain of Trk receptors TrkA, TrkB, and TrkC, an immunoglobulin (Ig)-like domain which binds to neurotrophin. The Trk family of receptors are tyrosine kinase receptors. They are activated by dimerization, leading to autophosphorylation of intracellular tyrosine residues, and triggering the signal transduction pathway. TrkA, TrkB, and TrkC share significant sequence homology and domain organization. The first three domains are leucine-rich domains while the fourth and fifth domains are Ig-like domains playing a part in ligand binding. TrkA, TrkB, and TrkC mediate the trophic effects of the neurotrophin Nerve Growth Factor (NGF) family. TrkA is recognized by NGF. TrkB is recognized by brain-derived neurotrophic factor (BDNF) and neurotrophin (NT)-4. TrkC is recognized by NT-3. NT-3 is promiscuous as in some cell systems it activates TrkA and TrkB receptors. TrkA is a receptor found in all major NGF targets, including the sympathetic, trigeminal, and dorsal root ganglia, cholinergic neurons of the basal forebrain, and the striatum. TrKB transcripts are found throughout multiple structures of the central and peripheral nervous systems. The TrkC gene is expressed throughout the mammalian nervous system. This group belongs to the I-set of IgSF domains.

Pssm-ID: 409360 Cd Length: 96 Bit Score: 41.24 E-value: 3.32e-04

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 2217265369  450 GSPIPTLRWFKNGQGSN---------LDGGNYHVYENGSLEIKMIRKEDQGIYTCVATNILGKAENQV 508
Cdd:cd04971     24 GNPKPTLTWYHNGAVLNesdyirteiHYEAATPTEYHGCLKFDNPTHVNNGNYTLVASNEYGQDSKSI 91

Fourth Ig-like domain from smooth muscle myosin light chain kinase and similar domains ; a member of the I-set of IgSF domains; The members here are composed of the fourth immunoglobulin (Ig)-like domain from smooth muscle myosin light chain kinase (MYLK) and similar domains. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structure of this group shows that the fourth Ig-like domain from myosin light chain kinase lacks this strand and thus belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409568 [Multi-domain] Cd Length: 90 Bit Score: 41.08 E-value: 3.35e-04

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  515 PTRIYRMPEDQVARRGTTVQLECRVKHDPSLKLTvsWLKDDEPL-YIGNRMKKEDDS--LTIFGVAERDQGSYTCVASTE 591
Cdd:cd20976      1 APSFSSVPKDLEAVEGQDFVAQCSARGKPVPRIT--WIRNAQPLqYAADRSTCEAGVgeLHIQDVLPEDHGTYTCLAKNA 78

                           90
                   ....*....|..
gi 2217265369  592 LDQDLAKAYLTV 603
Cdd:cd20976     79 AGQVSCSAWVTV 90

Immunoglobulin (Ig)-like domain of vascular endothelial growth factor receptor (VEGFR); member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the immunoglobulin (Ig)-like domain of vascular endothelial growth factor receptor (VEGFR). The VEGFRs have an extracellular component with seven Ig-like domains, a transmembrane segment, and an intracellular tyrosine kinase domain interrupted by a kinase-insert domain. The VEGFR family consists of three members, VEGFR-1 (Flt-1), VEGFR-2 (KDR/Flk-1), and VEGFR-3 (Flt-4). VEGFRs bind VEGFs with high affinity at the Ig-like domains. VEGF-A is important to the growth and maintenance of vascular endothelial cells and to the development of new blood- and lymphatic-vessels in physiological and pathological states. VEGFR-2 is a major mediator of the mitogenic, angiogenic, and microvascular permeability-enhancing effects of VEGF-A. VEGFR-1 may play an inhibitory part in these processes by binding VEGF and interfering with its interaction with VEGFR-2. VEGFR-1 has a signaling role in mediating monocyte chemotaxis. VEGFR-1 and VEGFR-2 may mediate a chemotactic and a survival signal in hematopoietic stem cells or leukemia cells. VEGFR-3 has been shown to be involved in tumor angiogenesis and growth. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409365 Cd Length: 90 Bit Score: 41.05 E-value: 3.40e-04

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  266 GVPTPDIAWYKKGgdLPSDKAKFENFNKALRITNVSEEDSGEYFCLASNKMGSIRHTISV 325
Cdd:cd04976     29 AYPPPEVVWYKDG--LPLTEKARYLTRHSLIIKEVTEEDTGNYTILLSNKQSNVFKNLTA 86

Second Ig-like domain of the giant muscle protein titin Z1z2 in the sarcomeric Z-disk, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the second immunoglobulin (Ig)-like domain of the giant muscle protein titin Z1z2 in the sarcomeric Z-disk and similar proteins. Titin is a key component in the assembly and functioning of vertebrate striated muscles. By providing connections at the level of individual microfilaments, it contributes to the fine balance of forces between the two halves of the sarcomere. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structure of the titin Z1z2 lacks this strand and thus it belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409564 [Multi-domain] Cd Length: 91 Bit Score: 41.03 E-value: 3.42e-04

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  330 APYWLDEPKNLILAPGEDGRLVCRANGNPKPTVQWMVNGEPLQSAPpnpnrevagdtiifrDTQISsravyqcNTSNEHG 409
Cdd:cd20972      1 PPQFIQKLRSQEVAEGSKVRLECRVTGNPTPVVRWFCEGKELQNSP---------------DIQIH-------QEGDLHS 58


                   ....*..
gi 2217265369  410 YLLANAF 416
Cdd:cd20972     59 LIIAEAF 65

Fourth immunoglobulin (Ig)-like domain in Robo (roundabout) receptors; member of the I-set of Ig superfamily (IgSF) domains; Members here are composed the fourth immunoglobulin (Ig)-like domain in Robo (roundabout) receptors. Robo receptors play a role in the development of the central nervous system (CNS), and are receptors of Slit protein. Slit is a repellant secreted by the neural cells in the midline. Slit acts through Robo to prevent most neurons from crossing the midline from either side. Three mammalian Robo homologs (Robo1, Robo2, Robo3), and three mammalian Slit homologs (Slit-1, Slit-2, Slit-3), have been identified. Commissural axons, which cross the midline, express low levels of Robo; longitudinal axons, which avoid the midline, express high levels of Robo. Robo1, Robo2, and Robo3 are expressed by commissural neurons in the vertebrate spinal cord and Slit-1, Slit-2, and Slit-3 are expressed at the ventral midline. Robo-3 is a divergent member of the Robo family which instead of being a positive regulator of Slit responsiveness, antagonizes Slit responsiveness in precrossing axons. The Slit-Robo interaction is mediated by the second leucine-rich repeat (LRR) domain of Slit and the two N-terminal Ig domains of Robo, Ig1 and Ig2. The primary Robo binding site for Slit2 has been shown by surface plasmon resonance experiments and mutational analysis to be the Ig1 domain, while the Ig2 domain has been proposed to harbor a weak secondary binding site. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409391 [Multi-domain] Cd Length: 98 Bit Score: 41.09 E-value: 3.57e-04

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  429 PRNQLirVILYNRTRLDCPFFGSPIPTLRWFKNGQGSNL-------DGGNYHVYENGSLEIKMIRKEDQGIYTCVATNIL 501
Cdd:cd05726      6 PRDQV--VALGRTVTFQCETKGNPQPAIFWQKEGSQNLLfpyqppqPSSRFSVSPTGDLTITNVQRSDVGYYICQALNVA 83

                           90
                   ....*....|...
gi 2217265369  502 GKAENQVRLEVKD 514
Cdd:cd05726     84 GSILAKAQLEVTD 96

First immunoglobulin (Ig) domain of contactin; member of the I-set of (Ig) superfamily domains; The members here are composed of the first immunoglobulin (Ig) domain of contactins. Contactins are neural cell adhesion molecules and are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. The first four Ig domains form the intermolecular binding fragment, which arranges as a compact U-shaped module via contacts between Ig domains 1 and 4, and between Ig domains 2 and 3. Contactin-2 (TAG-1, axonin-1) may play a part in the neuronal processes of neurite outgrowth, axon guidance and fasciculation, and neuronal migration. This group also includes contactin-1 and contactin-5. The different contactins show different expression patterns in the central nervous system. During development and in adulthood, contactin-2 is transiently expressed in subsets of central and peripheral neurons. Contactin-5 is expressed specifically in the rat postnatal nervous system, peaking at about 3 weeks postnatal, and a lack of contactin-5 (NB-2) results in an impairment of neuronal activity in the rat auditory system. Contactin-5 is highly expressed in the adult human brain in the occipital lobe and in the amygdala. Contactin-1 is differentially expressed in tumor tissues and may, through a RhoA mechanism, facilitate invasion and metastasis of human lung adenocarcinoma. This group belongs to the I-set of IgSF domains.

Pssm-ID: 409356 [Multi-domain] Cd Length: 96 Bit Score: 41.07 E-value: 3.70e-04

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  444 LDCPFFGSPIPTLRWFKNGQGSNLDGGNYHVYENGSLEIKM-IRKEDQGIYTCVATNILG 502
Cdd:cd04967     24 LNCRARANPVPSYRWLMNGTEIDLESDYRYSLVDGTLVISNpSKAKDAGHYQCLATNTVG 83

Immunoglobulin (Ig)-like domain of vascular endothelial growth factor receptor 3 (VEGFR-3); member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the immunoglobulin (Ig)-like domain of vascular endothelial growth factor receptor 3 (VEGFR-3). The VEGFRs have an extracellular component with seven Ig-like domains, a transmembrane segment, and an intracellular tyrosine kinase domain interrupted by a kinase-insert domain. VEGFRs bind VEGFs with high affinity at the Ig-like domains. VEGFR-3 (Flt-4) binds two members of the VEGF family (VEGF-C and VEGF-D) and is involved in tumor angiogenesis and growth. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409449 Cd Length: 88 Bit Score: 40.69 E-value: 3.71e-04

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  265 SGVPTPDIAWYKKGGDLPSdkakfENFNKALRITNVSEEDSGEYFCLASNKMGSIRHTIS 324
Cdd:cd05863     29 AAYPPPEFQWYKDGKLISG-----KHSPHSLQIKDVTEASAGTYTLVLWNSAAGLEKRIS 83

agrin-responsive second immunoglobulin-like domains (Ig2) of the Muscle-specific kinase (MuSK) ectodomain; a member of the I-set of Ig superfamily domains; The members here are composed of the second immunoglobulin-like (Ig) domains of the Muscle-specific kinase (MuSK) ectodomain. MuSK is a receptor tyrosine kinase specifically expressed in skeletal muscle, where it plays a central role in the formation and maintenance of the neuromuscular junction (NMJ). MuSK is activated by agrin, a neuron-derived heparan sulfate proteoglycan. The activation of MUSK in myotubes regulates the formation of NMJs through the regulation of different processes including the specific expression of genes in subsynaptic nuclei, the reorganization of the actin cytoskeleton and the clustering of the acetylcholine receptors (AChR) in the postsynaptic membrane. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structure of the MuSK lacks this strand and thus it belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409560 [Multi-domain] Cd Length: 88 Bit Score: 40.30 E-value: 4.70e-04

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 2217265369   54 LIECEAKGNPAPSFHWTRNSRFfnIAKDPRVSMRRrSGTLVIDfrsgGRPEEYEGEYQCFARNKFGTALSNRIRLQV 130
Cdd:cd20968     18 VLPCTTMGNPKPSVSWIKGDDL--IKENNRIAVLE-SGSLRIH----NVQKEDAGQYRCVAKNSLGIAYSKPVTIEV 87

Immunoglobulin (Ig)-like ectodomain of the LRIG1 (Leucine-rich Repeats And Immunoglobulin-like Domains Protein 1) and similar proteins; member of the I-set of IgSF domains; The members here are composed of subgroup of the immunoglobulin (Ig) domain found in the Ig superfamily. The Ig superfamily is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. A predominant feature of most Ig domains is a disulfide bridge connecting the two beta-sheets with a tryptophan residue packed against the disulfide bond. The ectodomain of LRIG1 has two distinct regions: the proposed 15 LRRs and three Ig-like domains closer to the membrane. LRIG1 has been reported to interact with many receptor tyrosine kinases, GDNF/c-Ret, E-cadherin, JAK/STAT, c-Met, and the EGFR family signaling systems. Immunoglobulin Superfamily (IgSF) domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. The structure of the LRIG1 extracellular Ig domain lacks a C" strand and thus is better described as a member of the I-set of IgSF domains.

Pssm-ID: 409420 [Multi-domain] Cd Length: 91 Bit Score: 40.68 E-value: 4.83e-04

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 2217265369  429 PRNqlIRVILYNRTRLDCPFFGSPIPTLRWFKNGqGSNLDGG---NYHVY-ENGSLEIKMIRKEDQGIYTCVATNILG 502
Cdd:cd05763      6 PHD--ITIRAGSTARLECAATGHPTPQIAWQKDG-GTDFPAArerRMHVMpEDDVFFIVDVKIEDTGVYSCTAQNSAG 80

C-terminal immunoglobulin-like domain of the myosin-associated giant protein kinase Twitchin, and similar domains; member of the I-set IgSF domains; The members here are composed of the C-terminal immunoglobulin-like domain of the myosin-associated giant protein kinase Twitchin and similar proteins, including Caenorhabditis elegans and Aplysia californica Twitchin, Drosophila melanogaster Projectin, and similar proteins. These are very large muscle proteins containing multiple immunoglobulin (Ig)-like and fibronectin type III (FN3) domains and a single kinase domain near the C-terminus. In humans these proteins are called Titin. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. The Ig-like domain of the Twitchin is a member of the I-set IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins (titin, telokin, and twitchin), the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D.

Pssm-ID: 409541 [Multi-domain] Cd Length: 89 Bit Score: 40.39 E-value: 4.94e-04

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 2217265369  247 ASSQMVLRGMDLLLECIASGVPTPDIAWYKKGGDLPSDKA---KFENFNKALRITNVSEEDSGEYFCLASNKMG 317
Cdd:cd20949      6 AYVTTVKEGQSATILCEVKGEPQPNVTWHFNGQPISASVAdmsKYRILADGLLINKVTQDDTGEYTCRAYQVNS 79

Third immunoglobulin (Ig)-like domain of the L1 cell adhesion molecule (CAM), and similar domains; The members here are composed of the third immunoglobulin (Ig)-like domain of the L1 cell adhesion molecule (CAM). L1 belongs to the L1 subfamily of cell adhesion molecules (CAMs) and is comprised of an extracellular region having six Ig-like domains and five fibronectin type III domains, a transmembrane region and an intracellular domain. L1 is primarily expressed in the nervous system and is involved in its development and function. L1 is associated with an X-linked recessive disorder, X-linked hydrocephalus, MASA syndrome, and spastic paraplegia type 1, that involves abnormalities of axonal growth. This group also contains the chicken neuron-glia cell adhesion molecule, Ng-CAM and human neurofascin.

Pssm-ID: 409394 [Multi-domain] Cd Length: 83 Bit Score: 40.09 E-value: 5.28e-04

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369   50 RDNIL-IECEAKGNPAPSFHWTR------NSRFF--NIAKdprvsmrrrsgTLVIDFRSggrpEEYEGEYQCFARNKFGT 120
Cdd:cd05731      9 RGGVLlLECIAEGLPTPDIRWIKlggelpKGRTKfeNFNK-----------TLKIENVS----EADSGEYQCTASNTMGS 73


                   .
gi 2217265369  121 A 121
Cdd:cd05731     74 A 74

Sixth immunoglobulin domain of the Drosophila melanogaster Dscam protein, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the sixth immunoglobulin domain of the Drosophila melanogaster Down syndrome cell adhesion molecule (DSCAM) protein and similar proteins. Down syndrome cell adhesion molecule (DSCAM) is a cell adhesion molecule that plays critical roles in neural development, including axon guidance and branching, axon target recognition, self-avoidance and synaptic formation. DSCAM belongs to the immunoglobulin superfamily and contributes to defects in the central nervous system in Down syndrome patients. Vertebrate DSCAMs differ from Drosophila Dscam1 in that they lack the extensive alternative splicing that occurs in the insect gene. Drosophila melanogaster Dscam has 38,016 isoforms generated by the alternative splicing of four variable exon clusters, which allows every neuron in the fly to display a distinctive set of Dscam proteins on its cell surface. Drosophila Dscam1 is a cell-surface protein that plays important roles in neural development and axon tiling of neurons. It is shown that thousands of isoforms bind themselves through specific homophilic (self-binding) interactions, a process which mediates cellular self-recognition. Drosophila Dscam2 is also alternatively spliced and plays a key role in the development of two visual system neurons, monopolar cells L1 and L2. This group is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand.

Pssm-ID: 409551 Cd Length: 94 Bit Score: 40.17 E-value: 6.13e-04

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 2217265369  255 GMDLLLECIASGVPTP-DIAWYKKGGDLPSDKA----KFENFNKALRITNVSEEDSGEYFCLASNKMGSIRHTISVRV 327
Cdd:cd20959     17 GMRAQLHCGVPGGDLPlNIRWTLDGQPISDDLGitvsRLGRRSSILSIDSLEASHAGNYTCHARNSAGSASYTAPLTV 94

Second immunoglobulin (Ig)-like domain of fibroblast growth factor (FGF) receptor, and similar domains; member of the I-set of IgSF domains; The members here are composed of the second immunoglobulin (Ig)-like domain of fibroblast growth factor (FGF) receptor. FGF receptors bind FGF signaling polypeptides. FGFs participate in multiple processes such as morphogenesis, development, and angiogenesis. FGFs bind to four FGF receptor tyrosine kinases (FGFR1, FGFR2, FGFR3, FGFR4). Receptor diversity is controlled by alternative splicing producing splice variants with different ligand binding characteristics and different expression patterns. FGFRs have an extracellular region comprised of three Ig-like domains, a single transmembrane helix, and an intracellular tyrosine kinase domain. Ligand binding and specificity reside in the Ig-like domains 2 and 3, and the linker region that connects these two. FGFR activation and signaling depend on FGF-induced dimerization, a process involving cell surface heparin or heparin sulfate proteoglycans. This group also contains fibroblast growth factor (FGF) receptor like-1(FGFRL1). FGFRL1 does not have a protein tyrosine kinase domain at its C-terminus; neither does its cytoplasmic domain appear to interact with a signaling partner. It has been suggested that FGFRL1 may not have any direct signaling function, but instead acts as a decoy receptor trapping FGFs and preventing them from binding other receptors.

Pssm-ID: 409393 [Multi-domain] Cd Length: 95 Bit Score: 40.28 E-value: 6.22e-04

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 2217265369  530 GTTVQLECRVKHDPslKLTVSWLKDDEPLYI-----GNRMKKEDDSLTIFGVAERDQGSYTCVASTE 591
Cdd:cd05729     19 ANKVRLECGAGGNP--MPNITWLKDGKEFKKehrigGTKVEEKGWSLIIERAIPRDKGKYTCIVENE 83

Third immunoglobulin domain of the Drosophila melanogaster Dscam protein, and similar domains; a member of the Constant 2 (C2)-set of IgSF domains; The members here are composed of the third immunoglobulin domain of the Drosophila melanogaster Down syndrome cell adhesion molecule (DSCAM) protein and similar proteins. Down syndrome cell adhesion molecule (DSCAM) is a cell adhesion molecule that plays critical roles in neural development, including axon guidance and branching, axon target recognition, self-avoidance and synaptic formation. DSCAM belongs to the immunoglobulin superfamily and contributes to defects in the central nervous system in Down syndrome patients. Vertebrate DSCAMs differ from Drosophila Dscam1 in that they lack the extensive alternative splicing that occurs in the insect gene. Drosophila melanogaster Dscam has 38,016 isoforms generated by the alternative splicing of four variable exon clusters, which allows every neuron in the fly to display a distinctive set of Dscam proteins on its cell surface. Drosophila Dscam1 is a cell-surface protein that plays important roles in neural development and axon tiling of neurons. It is shown that thousands of isoforms bind themselves through specific homophilic (self-binding) interactions, a process which mediates cellular self-recognition. Drosophila Dscam2 is also alternatively spliced and plays a key role in the development of two visual system neurons, monopolar cells L1 and L2. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. This group belongs to the C2-set of IgSF domains, having A, B, and E strands in one beta-sheet and A', G, F, C, and C' in the other. Unlike other Ig domain sets, the C2-set lacks the D strand.

Pssm-ID: 409549 [Multi-domain] Cd Length: 88 Bit Score: 40.21 E-value: 6.41e-04

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 2217265369  337 PKNLILAPGEDGRLVCRANGNPKPTVQWMVNGEPLqsapPNPNR--EVAGDTIIFRDTQISSRAVYQCNTSNE 407
Cdd:cd20957      8 PPVQTVDFGRTAVFNCSVTGNPIHTVLWMKDGKPL----GHSSRvqILSEDVLVIPSVKREDKGMYQCFVRND 76

Fourth immunoglobulin (Ig)-like domain of peroxidasin; The members here are composed of the fourth immunoglobulin (Ig)-like domain in peroxidasin. Peroxidasin has a peroxidase domain and interacting extracellular motifs containing four Ig-like domains. It has been suggested that peroxidasin is secreted, and has functions related to the stabilization of the extracellular matrix. It may play a part in various other important processes such as removal and destruction of cells which have undergone programmed cell death and protection of the organism against non-self.

Pssm-ID: 143223 Cd Length: 69 Bit Score: 39.47 E-value: 6.48e-04

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  260 LECIASGVPTPDIAWYKKGGDLpSDKAKFE-NFNKALRITNVSEEDSGEYFCLASNKMGS 318
Cdd:cd05746      3 IPCSAQGDPEPTITWNKDGVQV-TESGKFHiSPEGYLAIRDVGVADQGRYECVARNTIGY 61

Immunoglobulin (Ig)-like domain of the human basement membrane heparan sulfate proteoglycan perlecan and similar proteins; The members here are composed of the immunoglobulin (Ig)-like domain of the human basement membrane heparan sulfate proteoglycan perlecan, also known as HSPG2, and similar proteins. Perlecan consists of five domains: domain I has three putative heparan sulfate attachment sites, domain II has four LDL receptor-like repeats, and one Ig-like repeat, domain III resembles the short arm of laminin chains, domain IV has multiple Ig-like repeats (21 repeats in human perlecan), and domain V resembles the globular G domain of the laminin A chain and internal repeats of EGF. Perlecan may participate in a variety of biological functions including cell binding, LDL-metabolism, basement membrane assembly and selective permeability, calcium binding, and growth- and neurite-promoting activities.

Pssm-ID: 143220 Cd Length: 78 Bit Score: 39.40 E-value: 7.71e-04

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|.
gi 2217265369  345 GEDGRLVCRANGNPKPTVQWMVNGEPLQSAPPNPNREVAG-DTIIFRDTQISSRAVYQCNTSNEHGYLLAN 414
Cdd:cd05743      1 GETVEFTCVATGVPTPIINWRLNWGHVPDSARVSITSEGGyGTLTIRDVKESDQGAYTCEAINTRGMVFGI 71

Third immunoglobulin domain in Cluster of Differentiation (CD) 22; member of the Constant 2 (C2)-set of IgSF domains; The members here are composed of the third immunoglobulin domain in Cluster of Differentiation (CD) 22 (also known as Siglec-2). CD22, a sialic-acid binding immunoglobulin type-lectin (Siglec) family member, is an inhibitory co-receptor of the B-cell receptor (BCR). The inhibitory function of CD22 and its restricted expression on B cells makes CD22 an attractive target against dysregulated B cells that cause autoimmune diseases and B-cell-derived cancers. CD22 plays a vital role in establishing a baseline level of B-cell inhibition, and thus is an important determinant of homeostasis in humoral immunity. Siglecs are primarily expressed on immune cells and recognize sialic acid-containing glycan ligands. Siglecs are organized as an extracellular module composed of Ig-like domains (an N-terminal variable set of Ig-like carbohydrate recognition domains, and 1 to 16 constant Ig-like domains), followed by transmembrane and short cytoplasmic domains. Human Siglecs are classified into two subgroups, one subgroup is comprised of sialoadhesin (Siglec-1), CD22 (Siglec-2), and MAG (Siglec-4, myelin-associated glycoprotein), the other subgroup is comprised of CD33-related Siglecs which include CD33 (Siglec-3) and human Siglecs 5-11. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. This group belongs to the C2-set of IgSF domains, having A, B, and E strands in one beta-sheet and A', G, F, C' in the other. Unlike other Ig domain sets, the C2-set lacks the D strand.

Pssm-ID: 409531 Cd Length: 88 Bit Score: 39.78 E-value: 7.91e-04

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 2217265369  522 PEDQVARRGTTVQLECRVKHDPSLKLTVSWLKDdeplyiGNRMKKEDD-SLTIFGVAERDQGSYTCVASTEL 592
Cdd:cd20937      9 PSDAIVREGDSVTMTCEVSSSNPEYTTVSWLKD------GTSLKKQNTfTLNLREVTKDQSGKYCCQVSNDV 74

Second Ig-like domain of the giant muscle protein titin Z1z2 in the sarcomeric Z-disk, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the second immunoglobulin (Ig)-like domain of the giant muscle protein titin Z1z2 in the sarcomeric Z-disk and similar proteins. Titin is a key component in the assembly and functioning of vertebrate striated muscles. By providing connections at the level of individual microfilaments, it contributes to the fine balance of forces between the two halves of the sarcomere. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structure of the titin Z1z2 lacks this strand and thus it belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409564 [Multi-domain] Cd Length: 91 Bit Score: 39.87 E-value: 8.57e-04

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  515 PTRIYRMPEDQVARRGTTVQLECRVKHDPSLKltVSWLKDDEPLY--IGNRMKKEDD--SLTIFGVAERDQGSYTCVAST 590
Cdd:cd20972      1 PPQFIQKLRSQEVAEGSKVRLECRVTGNPTPV--VRWFCEGKELQnsPDIQIHQEGDlhSLIIAEAFEEDTGRYSCLATN 78

                           90
                   ....*....|...
gi 2217265369  591 ELDQDLAKAYLTV 603
Cdd:cd20972     79 SVGSDTTSAEIFV 91

Immunoglobulin (Ig)-like domain of carcinoembryonic antigen (CEA) related cell adhesion molecule (CEACAM) and similar proteins; The members here are composed of the immunoglobulin (Ig)-like domain in carcinoembryonic antigen (CEA) related cell adhesion molecule (CEACAM) and related domains. The CEA family is a group of anchored or secreted glycoproteins, expressed by epithelial cells, leukocytes, endothelial cells and placenta. The CEA family is divided into the CEACAM and pregnancy-specific glycoprotein (PSG) subfamilies. This group represents the CEACAM subfamily. CEACAM1 has many important cellular functions: it is a cell adhesion molecule and a signaling molecule that regulates the growth of tumor cells, an angiogenic factor, and a receptor for bacterial and viral pathogens, including mouse hepatitis virus (MHV). In mice, four isoforms of CEACAM1 generated by alternative splicing have either two (D1, D4) or four (D1-D4) Ig-like domains on the cell surface. This family corresponds to the D1 Ig-like domain. Also belonging to this group is the N-terminal immunoglobulin (Ig)-like domain of the signaling lymphocyte activation molecule (SLAM) family, CD84-like family. The SLAM family is a group of immune-cell specific receptors that can regulate both adaptive and innate immune responses. SLAM family proteins are organized as an extracellular domain with having two or four Ig-like domains, a single transmembrane segment, and a cytoplasmic region having Tyr-based motifs. The extracellular domain is organized as a membrane-distal Ig variable (IgV) domain that is responsible for ligand recognition and a membrane-proximal truncated Ig constant-2 (IgC2) domain.

Pssm-ID: 409403 Cd Length: 102 Bit Score: 40.19 E-value: 8.89e-04

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|.
gi 2217265369  456 LRWFKNGQG---SNLDGGNYHVYENGSLEIKMIRKEDQGIYTCVATNILGKAEN-QVRLEV 512
Cdd:cd05741     42 AEYENSSDEfraGSAFSGREYIYTNGSLLIQNITLSDTGFYTLESTNIGGKTESaTFQLHV 102

Immunoglobulin domain; Members of the immunoglobulin superfamily are found in hundreds of proteins of different functions. Examples include antibodies, the giant muscle kinase titin and receptor tyrosine kinases. Immunoglobulin-like domains may be involved in protein-protein and protein-ligand interactions.

Pssm-ID: 395002 Cd Length: 86 Bit Score: 39.49 E-value: 1.05e-03

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  429 PRNQLIRVILYNRTRLDC-PFFGSPIPTLRWFKNGQGSNLdgGNYHVYENG-----SLEIKMIRKEDQGIYTCVATNILG 502
Cdd:pfam00047    1 SAPPTVTVLEGDSATLTCsASTGSPGPDVTWSKEGGTLIE--SLKVKHDNGrttqsSLLISNVTKEDAGTYTCVVNNPGG 78


                   ..
gi 2217265369  503 KA 504
Cdd:pfam00047   79 SA 80

Immunoglobulin (Ig)-like domain of semaphorin 4D (Sema4D) and similar proteins; The members here are composed of the immunoglobulin (Ig)-like domain of semaphorin 4D (Sema4D) and similar proteins. Sema4D is a Class IV semaphorin. Semaphorins are classified based on structural features additional to the Sema domain. Sema4D has extracellular Sema and Ig domains, a transmembrane domain, and a short cytoplasmic domain. Sema4D plays a part in the development of GABAergic synapses. Sema4D in addition is an immune semaphorin. It is abundant on resting T cells; its expression is weak on resting B cells and antigen presenting cells (APCs), but is upregulated by various stimuli. The receptor used by Sema4D in the immune system is CD72. Sem4D enhances the activation of B cells and DCs through binding CD72, perhaps by reducing CD72s inhibitory signals. The receptor used by Sema4D in the non-lymphatic tissues is plexin-B1. Sem4D is anchored to the cell surface but its extracellular domain can be released from the cell surface by a metalloprotease-dependent process. Sem4D may mediate its effects in its membrane-bound form and/or its cleaved form.

Pssm-ID: 409457 Cd Length: 87 Bit Score: 39.41 E-value: 1.12e-03

                           10        20        30        40        50
                   ....*....|....*....|....*....|....*....|....*....|..
gi 2217265369  274 WYKKGGDLPSDKAKFENFNKALRITNVSEEDSGEYFCLASNKMGSIRHTISV 325
Cdd:cd05873     29 WKFQGKVLKAESPKYGLYGDGLLIFNASEADAGRYQCLSVEKSKAKTFFQTV 80

Third immunoglobulin (Ig)-like domain of the receptor protein tyrosine phosphatase (RPTP)-F (also known as LAR), type IIa; member of the I-set of IgSF domains; The members here are composed of the third immunoglobulin (Ig)-like domain found in the receptor protein tyrosine phosphatase (RPTP)-F, also known as LAR. LAR belongs to the RPTP type IIa subfamily. Members of this subfamily are cell adhesion molecule-like proteins involved in central nervous system (CNS) development. They have large extracellular portions comprised of multiple Ig-like domains and two to nine fibronectin type III (FNIII) domains and a cytoplasmic portion having two tandem phosphatase domains. Included in this group is Drosophila LAR (DLAR).

Pssm-ID: 409401 Cd Length: 82 Bit Score: 39.11 E-value: 1.14e-03

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  429 PRNQliRVILYNRTRLDCPFFGSPIPTLRWFKNGQgsNLDGGNYHVYENGSLEIKMIRkeDQGIYTCVATNILGKAENQV 508
Cdd:cd05739      4 PSNH--EVMPGGSVNLTCVAVGAPMPYVKWMKGGE--ELTKEDEMPVGRNVLELTNIY--ESANYTCVAISSLGMIEATA 77


                   ....*
gi 2217265369  509 RLEVK 513
Cdd:cd05739     78 QVTVK 82

Immunoglobulin (Ig) constant domain of the complement receptor of the immunoglobulin superfamily (CRIg); The members here are composed of the Immunoglobulin (Ig) constant domain of the complement receptor of the immunoglobulin superfamily (CRIg). The N-terminal domain of CRIg (also referred to as Z39Ig and V-set and Ig domain-containing 4 (VSIG4)) belongs to the IgV family of immunoglobulin-like domains while the C-terminal domain of CRIg belongs to the IgC family of immunoglobulin-like domains. CRIg plays a role in the complement system, an inhibitor of the alternative pathway convertases, and a negative regulator of T cell activation. The Ig superfamily is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. Members of this group are components of immunoglobulin, neuroglia, cell surface glycoproteins such as T-cell receptors, CD2, CD4, CD8, and membrane glycoproteins such as butyrophilin and chondroitin sulfate proteoglycan core protein. A predominant feature of most Ig domains is a disulfide bridge connecting the two beta-sheets with a tryptophan residue packed against the disulfide bond.

Pssm-ID: 409504 Cd Length: 86 Bit Score: 39.35 E-value: 1.15e-03

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 2217265369  252 VLRGMDLLLECIASGVPTPDIAWYKK--GGDLPSDKAKFEN--FNKALritnVSeeDSGEYFCLASNKMGSIRHTISVR 326
Cdd:cd16082     10 VPQGMRISLQCQAWGSPPISYVWYKEqtNNQEPIKVAALSTllFKPAV----VA--DSGSYFCTAKGRVGSEQRSDIVK 82

Immunoglobulin (Ig)-like I-set domain of Neural Cell Adhesion Molecule 1 (NCAM-1) and similar proteins; The members here are composed of the fourth immunoglobulin (Ig)-like domain of Neural Cell Adhesion Molecule (NCAM-1). NCAM plays important roles in the development and regeneration of the central nervous system, in synaptogenesis and neural migration. NCAM mediates cell-cell and cell-substratum recognition and adhesion via homophilic (NCAM-NCAM), and heterophilic (NCAM-non-NCAM), interactions. NCAM is expressed as three major isoforms having different intracellular extensions. The extracellular portion of NCAM has five N-terminal Ig-like domains and two fibronectin type III domains. The double zipper adhesion complex model for NCAM homophilic binding involves Ig1, Ig2, and Ig3. By this model, Ig1 and Ig2 mediate dimerization of NCAM molecules situated on the same cell surface (cis interactions), and Ig3 domains mediate interactions between NCAM molecules expressed on the surface of opposing cells (trans interactions), through binding to the Ig1 and Ig2 domains. The adhesive ability of NCAM is modulated by the addition of polysialic acid chains to the fifth Ig-like domain. Also included in this group is NCAM-2 (also known as OCAM/mamFas II and RNCAM) NCAM-2 is differentially expressed in the developing and mature olfactory epithelium (OE). One of the unique features of I-set domains is the lack of a C" strand. The structures of this group show that the Ig domain lacks this strand and thus is a member of the I-set of Ig domains.

Pssm-ID: 409395 [Multi-domain] Cd Length: 96 Bit Score: 39.43 E-value: 1.18e-03

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 2217265369  260 LECIASGVPTPDIAWyKKGGDLPSDKAKFENFN---------KALRITNVSEEDSGEYFCLASNKMG 317
Cdd:cd05732     21 LTCEAEGDPIPEITW-RRATRGISFEEGDLDGRivvrgharvSSLTLKDVQLTDAGRYDCEASNRIG 86

Fourth immunoglobulin (Ig)-like domain in neogenin, and similar domains; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the fourth immunoglobulin (Ig)-like domain in neogenin and related proteins. Neogenin is a cell surface protein which is expressed in the developing nervous system of vertebrate embryos in the growing nerve cells. It is also expressed in other embryonic tissues, and may play a general role in developmental processes such as cell migration, cell-cell recognition, and tissue growth regulation. Included in this group is the tumor suppressor protein DCC which is deleted in colorectal carcinoma. DCC and neogenin each have four Ig-like domains followed by six fibronectin type III domains, a transmembrane domain, and an intracellular domain. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409388 Cd Length: 84 Bit Score: 39.10 E-value: 1.19e-03

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  522 PEDQVARRGTTVQLECRVKHDPSLklTVSWLKDDEPLYIGNRMK-KEDDSLTIFGVAERDQGSYTCVASTELDQDLAKAY 600
Cdd:cd05723      4 PSNIYAHESMDIVFECEVTGKPTP--TVKWVKNGDVVIPSDYFKiVKEHNLQVLGLVKSDEGFYQCIAENDVGNAQASAQ 81


                   ...
gi 2217265369  601 LTV 603
Cdd:cd05723     82 LII 84

Immunoglobulin (Ig)-like I-set domain of Neural Cell Adhesion Molecule 1 (NCAM-1); The members here are composed of the fourth Ig domain of Neural Cell Adhesion Molecule 1(NCAM-1). NCAM plays important roles in the development and regeneration of the central nervous system, in synaptogenesis and neural migration. NCAM mediates cell-cell and cell-substratum recognition and adhesion via homophilic (NCAM-NCAM) and heterophilic (NCAM-non-NCAM) interactions. NCAM is expressed as three major isoforms having different intracellular extensions. The extracellular portion of NCAM has five N-terminal Ig-like domains and two fibronectin type III domains. The double zipper adhesion complex model for NCAM homophilic binding involves Ig1, Ig2, and Ig3. By this model, Ig1 and Ig2 mediate dimerization of NCAM molecules situated on the same cell surface (cis interactions), and Ig3 domains mediate interactions between NCAM molecules expressed on the surface of opposing cells (trans interactions), through binding to the Ig1 and Ig2 domains. The adhesive ability of NCAM is modulated by the addition of polysialic acid chains to the fifth Ig-like domain. One of the unique features of I-set domains is the lack of a C" strand. The structures of this group show that the Ig domain lacks this strand and thus is a member of the I-set of Ig domains.

Pssm-ID: 143277 [Multi-domain] Cd Length: 97 Bit Score: 39.58 E-value: 1.19e-03

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 2217265369  260 LECIASGVPTPDIAWyKKGGDLPSDKAKFENFN---------KALRITNVSEEDSGEYFCLASNKMG 317
Cdd:cd05869     22 LTCEASGDPIPSITW-RTSTRNISSEEKTLDGHivvrsharvSSLTLKYIQYTDAGEYLCTASNTIG 87

Second immunoglobulin (Ig)-like domain of protein tyrosine kinase (PTK) 7; The members here are composed of the second immunoglobulin (Ig)-like domain in protein tyrosine kinase (PTK) 7, also known as CCK4. PTK7 is a subfamily of the receptor protein tyrosine kinase family, and is referred to as an RPTK-like molecule. RPTKs transduce extracellular signals across the cell membrane and play important roles in regulating cell proliferation, migration, and differentiation. PTK7 is organized as an extracellular portion having seven Ig-like domains, a single transmembrane region, and a cytoplasmic tyrosine kinase-like domain. PTK7 is considered a pseudokinase as it has several unusual residues in some of the highly conserved tyrosine kinase (TK) motifs; it is predicted to lack TK activity. PTK7 may function as a cell-adhesion molecule. PTK7 mRNA is expressed at high levels in placenta, melanocytes, liver, lung, pancreas, and kidney. PTK7 is overexpressed in several cancers, including melanoma and colon cancer lines.

Pssm-ID: 409417 Cd Length: 95 Bit Score: 39.53 E-value: 1.32e-03

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 2217265369  441 RTRLDCPFFGSPIPTLRWFKNGQGSNLDGGNYHVY-ENGSLEIKMIRKEDQGIYTCVATNILGKA 504
Cdd:cd05760     18 RVTLRCHIDGHPRPTYQWFRDGTPLSDGQGNYSVSsKERTLTLRSAGPDDSGLYYCCAHNAFGSV 82

Immunoglobulin I-set domain;

Pssm-ID: 400151 [Multi-domain] Cd Length: 90 Bit Score: 39.16 E-value: 1.34e-03

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 2217265369  141 LDPVVVQEGAPLTLQCNpPPGLPSPVIFWMSSSmEPITQDKRVSQGHNGDLYF---SNVMLQDMQTdYSCNA 209
Cdd:pfam07679    7 PKDVEVQEGESARFTCT-VTGTPDPEVSWFKDG-QPLRSSDRFKVTYEGGTYTltiSNVQPDDSGK-YTCVA 75

C-terminal immunoglobulin (Ig)-like domain of M-protein; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the C-terminal immunoglobulin (Ig)-like domain of M-protein (also known as myomesin-2). M-protein is a structural protein localized to the M-band, a transverse structure in the center of the sarcomere, and is a candidate for M-band bridges. M-protein is modular consisting mainly of repetitive IG-like and fibronectin type III (FnIII) domains and has a muscle-type specific expression pattern. M-protein is present in fast fibers.

Pssm-ID: 143299 Cd Length: 92 Bit Score: 39.12 E-value: 1.34e-03

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|..
gi 2217265369  444 LDCPFFGSPIPTLRWFKNGQGSNLDGGNYHVYENG---SLEIKMIRKEDQGIYTCVATNILG 502
Cdd:cd05891     21 LTCTVFGNPDPEVIWFKNDQDIELSEHYSVKLEQGkyaSLTIKGVTSEDSGKYSINVKNKYG 82

Third immunoglobulin (Ig)-like domain of the L1 cell adhesion molecule (CAM); The members here are composed of the third immunoglobulin (Ig)-like domain of the L1 cell adhesion molecule (CAM). L1 belongs to the L1 subfamily of cell adhesion molecules (CAMs) and is comprised of an extracellular region having six Ig-like domains, five fibronectin type III domains, a transmembrane region and an intracellular domain. L1 is primarily expressed in the nervous system and is involved in its development and function. L1 is associated with an X-linked recessive disorder, X-linked hydrocephalus, MASA syndrome, or spastic paraplegia type 1, that involves abnormalities of axonal growth. This group also contains the chicken neuron-glia cell adhesion molecule, Ng-CAM.

Pssm-ID: 409460 [Multi-domain] Cd Length: 83 Bit Score: 39.12 E-value: 1.36e-03

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|.
gi 2217265369  444 LDCPFFGSPIPTLRWFKNGQGSNLDGGNYHvYENGSLEIKMIRKEDQGIYTCVATNILGKA 504
Cdd:cd05876     15 LECIAEGLPTPTVKWLRPSGPLPPDRVKYQ-NHNKTLQLLNVGESDDGEYVCLAENSLGSA 74

Immunoglobulin I-set domain of the Leucine-rich repeat and immunoglobin-like domain-containing protein 1 (Lingo-1); The members here are composed of the immunoglobulin I-set (IgI) domain of the Leucine-rich repeat and immunoglobin-like domain-containing protein 1 (Lingo-1). Human Lingo-1 is a central nervous system-specific transmembrane glycoprotein also known as LERN-1, which functions as a negative regulator of neuronal survival, axonal regeneration, and oligodendrocyte differentiation and myelination. Lingo-1 is a key component of the Nogo receptor signaling complex (RTN4R/NGFR) in RhoA activation responsible for some inhibition of axonal regeneration by myelin-associated factors. The ligand-binding ectodomain of human Lingo-1 contains a bimodular, kinked structure composed of leucine-rich repeat (LRR) and immunoglobulin (Ig)-like modules. Diseases associated with Lingo-1 include mental retardation, autosomal recessive 64 and essential tremor. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structure of the Lingo-1 lacks this strand and thus it belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409561 Cd Length: 92 Bit Score: 39.30 E-value: 1.52e-03

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 2217265369  255 GMDLLLECIASGVPTPDIAWYKKGGDLPSDKAKFENF---NKALRITNVSEEDSGEYFCLASNKMGSIRHTISVRV 327
Cdd:cd20969     17 GHTVQFVCRADGDPPPAILWLSPRKHLVSAKSNGRLTvfpDGTLEVRYAQVQDNGTYLCIAANAGGNDSMPAHLHV 92

First immunoglobulin (Ig)-like domain in neogenin, and similar domains; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the first immunoglobulin (Ig)-like domain in neogenin and related proteins. Neogenin is a cell surface protein which is expressed in the developing nervous system of vertebrate embryos in the growing nerve cells. It is also expressed in other embryonic tissues and may play a general role in developmental processes such as cell migration, cell-cell recognition, and tissue growth regulation. Included in this group is the tumor suppressor protein DCC which is deleted in colorectal carcinoma. DCC and neogenin each have four Ig-like domains followed by six fibronectin type III domains, a transmembrane domain, and an intracellular domain. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409387 Cd Length: 97 Bit Score: 39.38 E-value: 1.54e-03

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 2217265369  522 PEDQVARRGTTVQLECRVKHDPSLKltVSWLKDDEPLYIG---NRMKKEDDSLTIFGVAER-----DQGSYTCVASTE 591
Cdd:cd05722      8 PSDIVAMRGGPVVLNCSAESDPPPK--IEWKKDGVLLNLVsdeRRQQLPNGSLLITSVVHSkhnkpDEGFYQCVAQNE 83

Second immunoglobulin (Ig)-like domain of fibroblast growth factor (FGF) receptor; member of the I-set of IgSF domains; The members here are composed of the second immunoglobulin (Ig)-like domain of fibroblast growth factor (FGF) receptor. FGF receptors bind FGF signaling polypeptides. FGFs participate in multiple processes such as morphogenesis, development, and angiogenesis. FGFs bind to four FGF receptor tyrosine kinases (FGFR1, FGFR2, FGFR3, FGFR4). Receptor diversity is controlled by alternative splicing producing splice variants with different ligand binding characteristics and different expression patterns. FGFRs have an extracellular region comprised of three IG-like domains, a single transmembrane helix, and an intracellular tyrosine kinase domain. Ligand binding and specificity reside in the Ig-like domains 2 and 3, and the linker region that connects these two. FGFR activation and signaling depend on FGF-induced dimerization, a process involving cell surface heparin or heparin sulfate proteoglycans.

Pssm-ID: 409443 [Multi-domain] Cd Length: 95 Bit Score: 39.07 E-value: 1.79e-03

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 2217265369  530 GTTVQLECRVKHDPslKLTVSWLKDDEPLYIGNRM-----KKEDDSLTIFGVAERDQGSYTCVASTE 591
Cdd:cd05857     19 ANTVKFRCPAAGNP--TPTMRWLKNGKEFKQEHRIggykvRNQHWSLIMESVVPSDKGNYTCVVENE 83

Immunoglobulin Variable (IgV) domain in HERV-H LTR-associating 2 (HHLA2); The members here are composed of the immunoglobulin variable (IgV) region in HERV-H LTR-associating 2 (HHLA2; also known as B7-H7/B7 homolog 7). HHLA2 is a member of the B7 family of immune regulatory proteins. Mature human HHLA2 consists of an extracellular domain (ECD) with three immunoglobulin-like domains, a transmembrane segment, and a cytoplasmic domain. HHLA2 is widely expressed in human cancers including non-small cell lung carcinoma (NSCLS), triple negative breast cancer (TNBC), and melanoma, but has limited expression on normal tissues. Interestingly, unlike other members of B7 family, HHLA2 is not expressed in mice or rats. HHLA2 functions as a T cell coinhibitory molecules as it inhibits the proliferation of activated CD4(+) and CD8(+) T cells and their cytokine production. Furthermore, HHLA2 is constitutively expressed on the surface of human monocytes and is induced on B cells after stimulation, however it is not inducible on T cells.

Pssm-ID: 409512 Cd Length: 107 Bit Score: 39.29 E-value: 1.87e-03

                           10        20        30
                   ....*....|....*....|....*....|....*.
gi 2217265369  477 NGSLEIKMIRKEDQGIYTCVATNILGKAENQVRLEV 512
Cdd:cd16091     72 NASLLLRRVQLQDEGRYKCYTSTIIGNQESFVNLKV 107

Second immunoglobulin domain of the Drosophila melanogaster Dscam protein, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the second immunoglobulin domain of the Drosophila melanogaster Down syndrome cell adhesion molecule (DSCAM) protein and similar proteins. DSCAM is a cell adhesion molecule that plays critical roles in neural development, including axon guidance and branching, axon target recognition, self-avoidance and synaptic formation. DSCAM belongs to the immunoglobulin superfamily and contributes to defects in the central nervous system in Down syndrome patients. Vertebrate DSCAMs differ from Drosophila Dscam1 in that they lack the extensive alternative splicing that occurs in the insect gene. Drosophila melanogaster Dscam has 38,016 isoforms generated by the alternative splicing of four variable exon clusters, which allows every neuron in the fly to display a distinctive set of Dscam proteins on its cell surface. Drosophila Dscam1 is a cell-surface protein that plays important roles in neural development and axon tiling of neurons. It is shown that thousands of isoforms bind themselves through specific homophilic (self-binding) interactions, a process which mediates cellular self-recognition. Drosophila Dscam2 is also alternatively spliced and plays a key role in the development of two visual system neurons, monopolar cells L1 and L2. This group is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand.

Pssm-ID: 409545 Cd Length: 95 Bit Score: 39.06 E-value: 1.96e-03

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  423 PPRMLSPRN-QLIRVILYNRTRLDCPFFGSPIPTLRWFKNGQGSNLDGG---NYHVYE-NGSLEIKMIRKEDQGIYTCVA 497
Cdd:cd20953      1 APKIPGLSKsQPLTVSSASSIALLCPAQGYPAPSFRWYKFIEGTTRKQAvvlNDRVKQvSGTLIIKDAVVEDSGKYLCVV 80


                   ....*
gi 2217265369  498 TNILG 502
Cdd:cd20953     81 NNSVG 85

Third immunoglobulin (Ig)-like domain of fibroblast growth factor receptor (FGFR); member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the third immunoglobulin (Ig)-like domain of fibroblast growth factor receptor (FGFR). Fibroblast growth factors (FGFs) participate in morphogenesis, development, angiogenesis, and wound healing. These FGF-stimulated processes are mediated by four FGFR tyrosine kinases (FGRF1-4). FGFRs are comprised of an extracellular portion consisting of three Ig-like domains, a transmembrane helix, and a cytoplasmic portion having protein tyrosine kinase activity. The highly conserved Ig-like domains 2 and 3, and the linker region between D2 and D3 define a general binding site for FGFs. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409363 Cd Length: 102 Bit Score: 38.94 E-value: 1.97e-03

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  522 PEDQVARRGTTVQLECRVKHDPslKLTVSWLKDDE----PLY------------IGNRMKKEDDSLTIFGVAERDQGSYT 585
Cdd:cd04974      8 PANQTVVLGSDVEFHCKVYSDA--QPHIQWLKHVEvngsKYGpdglpyvtvlkvAGVNTTGEENTLTISNVTFDDAGEYI 85

                           90
                   ....*....|....*..
gi 2217265369  586 CVASTELDQDLAKAYLT 602
Cdd:cd04974     86 CLAGNSIGLSFHSAWLT 102

C-terminal immunoglobulin-like domain of the myosin-associated giant protein kinase Twitchin, and similar domains; member of the I-set IgSF domains; The members here are composed of the C-terminal immunoglobulin-like domain of the myosin-associated giant protein kinase Twitchin and similar proteins, including Caenorhabditis elegans and Aplysia californica Twitchin, Drosophila melanogaster Projectin, and similar proteins. These are very large muscle proteins containing multiple immunoglobulin (Ig)-like and fibronectin type III (FN3) domains and a single kinase domain near the C-terminus. In humans these proteins are called Titin. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. The Ig-like domain of the Twitchin is a member of the I-set IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins (titin, telokin, and twitchin), the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D.

Pssm-ID: 409541 [Multi-domain] Cd Length: 89 Bit Score: 38.85 E-value: 2.04e-03

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 2217265369  528 RRGTTVQLECRVKHDPslKLTVSWLKDDEPLYIG----NRMKKEDDSLTIFGVAERDQGSYTCVA 588
Cdd:cd20949     12 KEGQSATILCEVKGEP--QPNVTWHFNGQPISASvadmSKYRILADGLLINKVTQDDTGEYTCRA 74

Immunoglobulin (Ig)-like domain of the L1 cell adhesion molecule (CAM) and similar proteins; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the first immunoglobulin (Ig)-like domain of the L1 cell adhesion molecule (CAM). L1 belongs to the L1 subfamily of cell adhesion molecules (CAMs) and is comprised of an extracellular region having six Ig-like domains and five fibronectin type III domains, a transmembrane region and an intracellular domain. L1 is primarily expressed in the nervous system and is involved in its development and function. L1 is associated with an X-linked recessive disorder, X-linked hydrocephalus, MASA syndrome, or spastic paraplegia type 1, that involves abnormalities of axonal growth. This group also contains NrCAM [Ng(neuronglia)CAM-related cell adhesion molecule], which is primarily expressed in the nervous system, and human neurofascin. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lacks a C" strand.

Pssm-ID: 409396 [Multi-domain] Cd Length: 94 Bit Score: 38.93 E-value: 2.10e-03

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 2217265369  444 LDCPFFGSPIPTLRWFKNGQGSNLDGG-NYHVYEN-GSLEI--KMIRKED-QGIYTCVATNILGKA-ENQVRL 510
Cdd:cd05733     21 IKCEAKGNPQPTFRWTKDGKFFDPAKDpRVSMRRRsGTLVIdnHNGGPEDyQGEYQCYASNELGTAiSNEIRL 93

Third immunoglobulin (Ig)-like domain of fibroblast growth factor receptor 2 (FGFR2); member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the third immunoglobulin (Ig)-like domain of human fibroblast growth factor receptor 2 (FGFR2). Fibroblast growth factors (FGFs) participate in morphogenesis, development, angiogenesis, and wound healing. These FGF-stimulated processes are mediated by four FGFR tyrosine kinases (FGRF1-4). FGFRs are comprised of an extracellular portion consisting of three Ig-like domains, a transmembrane helix, and a cytoplasmic portion having protein tyrosine kinase activity. The highly conserved Ig-like domains 2 and 3, and the linker region between D2 and D3 define a general binding site for FGFs. FGFR2 is required for male sex determination. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409444 Cd Length: 105 Bit Score: 39.17 E-value: 2.12e-03

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  245 GTASSQMVLRGMDLLLECIASGVPTPDIAWYK----KGGDLPSDKAKFENFNKA------------LRITNVSEEDSGEY 308
Cdd:cd05858      6 GLPANTSVVVGTDAEFVCKVYSDAQPHIQWLKhvekNGSKYGPDGLPYVEVLKTagvnttdkeievLYLRNVTFEDAGEY 85

                           90
                   ....*....|....
gi 2217265369  309 FCLASNKMGSIRHT 322
Cdd:cd05858     86 TCLAGNSIGISHHS 99

Immunoglobulin V-set domain; This domain is found in antibodies as well as neural protein P0 and CTL4 amongst others.

Pssm-ID: 462230 Cd Length: 109 Bit Score: 38.98 E-value: 2.26e-03

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  459 FKNGQGSNLDGGNYHV-----YENGSLEIKMIRKEDQGIYTC-VATNILGKAENQVRLEV 512
Cdd:pfam07686   49 YSNGSEEGVKKGRFSGrgdpsNGDGSLTIQNLTLSDSGTYTCaVIPSGEGVFGKGTRLTV 108

Fourth immunoglobulin (Ig)-like domain in Robo (roundabout) receptors; member of the I-set of Ig superfamily (IgSF) domains; Members here are composed the fourth immunoglobulin (Ig)-like domain in Robo (roundabout) receptors. Robo receptors play a role in the development of the central nervous system (CNS), and are receptors of Slit protein. Slit is a repellant secreted by the neural cells in the midline. Slit acts through Robo to prevent most neurons from crossing the midline from either side. Three mammalian Robo homologs (Robo1, Robo2, Robo3), and three mammalian Slit homologs (Slit-1, Slit-2, Slit-3), have been identified. Commissural axons, which cross the midline, express low levels of Robo; longitudinal axons, which avoid the midline, express high levels of Robo. Robo1, Robo2, and Robo3 are expressed by commissural neurons in the vertebrate spinal cord and Slit-1, Slit-2, and Slit-3 are expressed at the ventral midline. Robo-3 is a divergent member of the Robo family which instead of being a positive regulator of Slit responsiveness, antagonizes Slit responsiveness in precrossing axons. The Slit-Robo interaction is mediated by the second leucine-rich repeat (LRR) domain of Slit and the two N-terminal Ig domains of Robo, Ig1 and Ig2. The primary Robo binding site for Slit2 has been shown by surface plasmon resonance experiments and mutational analysis to be the Ig1 domain, while the Ig2 domain has been proposed to harbor a weak secondary binding site. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409391 [Multi-domain] Cd Length: 98 Bit Score: 38.78 E-value: 2.27e-03

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 2217265369  250 QMVLRGMDLLLECIASGVPTPDIAWYKKGGDL-------PSDKAKFENFNKA-LRITNVSEEDSGEYFCLASNKMGSI 319
Cdd:cd05726      9 QVVALGRTVTFQCETKGNPQPAIFWQKEGSQNllfpyqpPQPSSRFSVSPTGdLTITNVQRSDVGYYICQALNVAGSI 86

Second immunoglobulin (Ig)-like domain of interleukin-1 receptor (IL1R), and similar domains; The members here are composed of the second immunoglobulin (Ig)-like domain of interleukin-1 receptor (IL1R; also known as cluster of differentiation (CD) 121). IL-1 alpha and IL-1 beta are cytokines which participate in the regulation of inflammation, immune responses, and hematopoiesis. These cytokines bind to the IL-1 receptor type 1 (IL1R1), which is activated on additional association with interleukin-1 receptor accessory protein (IL1RAP). IL-1 also binds a second receptor designated type II (IL1R2). Mature IL1R1 consists of three IG-like domains, a transmembrane domain, and a large cytoplasmic domain. Mature IL1R2 is organized similarly except that it has a short cytoplasmic domain. The latter does not initiate signal transduction. A naturally occurring cytokine IL-1RA (IL-1 receptor antagonist) is widely expressed and binds to IL-1 receptors, inhibiting the binding of IL-1 alpha and IL-1 beta. This group also contains ILIR-like 1 (IL1R1L) which maps to the same chromosomal location as IL1R1 and IL1R2.

Pssm-ID: 409415 Cd Length: 92 Bit Score: 38.46 E-value: 2.46e-03

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  269 TPDIAWYKkggdlpsDKAKFENFNK------ALRITNVSEEDSGEYFCLAS-NKMGSIRH---TISVRVK 328
Cdd:cd05757     29 LPPIQWYK-------DCKPLQGDKRfipkgsKLLIQNVTEEDAGNYTCKFTyTHNGKQYNvtrTISLTVT 91

Immunoglobulin (Ig)-like variable (V) domain of the Signal-Regulatory Protein (SIRP); The members here are composed of the immunoglobulin (Ig)-like domain of the Signal-Regulatory Protein (SIRP). The SIRPs belong to the "paired receptors" class of membrane proteins that comprise several genes coding for proteins with similar extracellular regions, but very different transmembrane/cytoplasmic regions with different (activating or inhibitory) signaling potentials. They are commonly on NK cells, but are also on many myeloid cells. Their extracellular region contains three immunoglobulin superfamily domains, a single V-set, and two C1-set IgSF domains. Their cytoplasmic tails that contain either ITIMs or transmembrane regions have positively charged residues that allow an association with adaptor proteins, such as DAP12/KARAP, containing ITAMs. There are 3 distinct SIRP members: alpha, beta, and gamma. SIRP alpha (also known as CD172a or SRC homology 2 domain-containing protein tyrosine phosphatase substrate 1/Shps-1) is a membrane receptor that interacts with a ligand CD47 expressed on many cells and gives an inhibitory signal through immunoreceptor tyrosine-based inhibition motifs in the cytoplasmic region that interact with phosphatases SHP-1 and SHP-2. SIRP beta has a short cytoplasmic region and associates with a transmembrane adapter protein DAP12 containing immunoreceptor tyrosine-based activation motifs to give an activating signal. SIRP gamma contains a very short cytoplasmic region lacking obvious signaling motifs, but also binds CD47 with much less affinity. Members of this group contain standard Ig superfamily V-set AGFCC'C"/DEB domain topology.

Pssm-ID: 409516 Cd Length: 111 Bit Score: 39.08 E-value: 2.47e-03

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  249 SQMVLRGMDLLLEC-IASGVPTPDIAWYK------------KGGDLP-----SDKAKFENFNKALRITNVSEEDSGEYFC 310
Cdd:cd16097      8 SVSVAAGESATLHCtVTSLIPVGPIQWFRgagpgreliynqKEGHFPrvttvSDLTKRNNMDFSIRISNITPADAGTYYC 87


                   ....*
gi 2217265369  311 LASNK 315
Cdd:cd16097     88 VKFRK 92

C-terminal immunoglobulin (Ig)-like domain of myotilin; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the C-terminal immunoglobulin (Ig)-like domain of myotilin. Mytolin belongs to the palladin-myotilin-myopalladin family. Proteins belonging to the latter family contain multiple Ig-like domains and function as scaffolds, modulating the actin cytoskeleton. Myotilin is most abundant in skeletal and cardiac muscle and is involved in maintaining sarcomere integrity. It binds to alpha-actinin, filamin, and actin. Mutations in myotilin lead to muscle disorders. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409473 Cd Length: 92 Bit Score: 38.60 E-value: 2.54e-03

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  430 RNQLIRVILYNRTRLDCPFFGSPIPTLRWFKNGQGSNLDGGNYHVYENGS----LEIKMIRKEDQGIYTCVATNILGKAE 505
Cdd:cd05892      6 KPQNKKVLEGDPVRLECQISAIPPPQIFWKKNNEMLQYNTDRISLYQDNCgricLLIQNANKKDAGWYTVSAVNEAGVVS 85


                   ....*..
gi 2217265369  506 NQVRLEV 512
Cdd:cd05892     86 CNARLDV 92

Second Ig-like domain of Junctional adhesion molecule-1 (JAM1); a member of the I-set of IgSF domains; The members here are composed of the second Ig-like domain of Junctional adhesion molecule-1 (JAM1). JAM1 is an immunoglobulin superfamily (IgSF) protein with two Ig-like domains in its extracellular region; it plays a role in the formation of endothelial and epithelial tight junction and acts as a receptor for mammalian reovirus sigma-1. The IgSF is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. The two sheets are linked together by a conserved disulfide bond between B strand and F strand. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. The second Ig-like domain of JAM1 is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, the A strand of the I-set is discontinuous but lacks a C" strand. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors.

Pssm-ID: 409542 Cd Length: 97 Bit Score: 38.45 E-value: 2.63e-03

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  440 NRTRLDCPFF-GSPIPTLRWFKNGQGSNLDGGNYHVYEN---------GSLEIKMIRKEDQGIYTCVATNILGKAE--NQ 507
Cdd:cd20950     13 NRAVLTCSEPdGSPPSEYTWFKDGVVMPTNPKSTRAFSNssysldpttGELVFDPLSASDTGEYSCEARNGYGTPMrsNA 92


                   ....*
gi 2217265369  508 VRLEV 512
Cdd:cd20950     93 VRMEA 97

Immunoglobulin (Ig)-like domain in neuregulins; The members here are composed of the immunoglobulin (Ig)-like domain in neuregulins (NRGs). NRGs are signaling molecules which participate in cell-cell interactions in the nervous system, breast, heart, and other organ systems, and are implicated in the pathology of diseases including schizophrenia, multiple sclerosis, and breast cancer. There are four members of the neuregulin gene family (NRG-1, NRG-2, NRG-3, and NRG-4). The NRG-1 protein, binds to and activates the tyrosine kinases receptors ErbB3 and ErbB4, initiating signaling cascades. The other NRGs proteins bind one or the other or both of these ErbBs. NRG-1 has multiple functions: in the brain it regulates various processes such as radial glia formation and neuronal migration, dendritic development, and expression of neurotransmitters receptors, while in the peripheral nervous system NRG-1 regulates processes such as target cell differentiation, and Schwann cell survival. There are many NRG-1 isoforms which arise from the alternative splicing of mRNA. Less is known of the functions of the other NRGs. NRG-2 and NRG-3 are expressed predominantly in the nervous system. NRG-2 is expressed by motor neurons and terminal Schwann cells, and is concentrated near synaptic sites and may be a signal that regulates synaptic differentiation. NRG-4 has been shown to direct pancreatic islet cell development towards the delta-cell lineage.

Pssm-ID: 409408 [Multi-domain] Cd Length: 92 Bit Score: 38.26 E-value: 2.70e-03

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369   43 KDHIVDPRDNILIECEAKG-NPAPSFHWTRNSRFFNIAKDPRVSMRRRSGTLVIDFRSGGRpeEYEGEYQCFARNKFGTA 121
Cdd:cd05750      7 KSQTVQEGSKLVLKCEATSeNPSPRYRWFKDGKELNRKRPKNIKIRNKKKNSELQINKAKL--EDSGEYTCVVENILGKD 84


                   ....*....
gi 2217265369  122 lSNRIRLQV 130
Cdd:cd05750     85 -TVTGNVTV 92

Fourth immunoglobulin domain of the Drosophila melanogaster Dscam protein, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the fourth immunoglobulin domain of the Drosophila melanogaster Down syndrome cell adhesion molecule (DSCAM) protein and similar proteins. Down syndrome cell adhesion molecule (DSCAM) is a cell adhesion molecule that plays critical roles in neural development, including axon guidance and branching, axon target recognition, self-avoidance and synaptic formation. DSCAM belongs to the immunoglobulin superfamily and contributes to defects in the central nervous system in Down syndrome patients. Vertebrate DSCAMs differ from Drosophila Dscam1 in that they lack the extensive alternative splicing that occurs in the insect gene. Drosophila melanogaster Dscam has 38,016 isoforms generated by the alternative splicing of four variable exon clusters, which allows every neuron in the fly to display a distinctive set of Dscam proteins on its cell surface. Drosophila Dscam1 is a cell-surface protein that plays important roles in neural development and axon tiling of neurons. It is shown that thousands of isoforms bind themselves through specific homophilic (self-binding) interactions, a process which mediates cellular self-recognition. Drosophila Dscam2 is also alternatively spliced and plays a key role in the development of two visual system neurons, monopolar cells L1 and L2. This group is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand.

Pssm-ID: 409548 [Multi-domain] Cd Length: 96 Bit Score: 38.31 E-value: 2.76e-03

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 2217265369  341 ILAPGEDGRLVCRANGNPKPTVQWMVNGEPLqsaPPNPNREVaGDTIIFRDTQIS----SRA------VYQCNTSNEHG 409
Cdd:cd20956     12 TLQPGPSVSLKCVASGNPLPQITWTLDGFPI---PESPRFRV-GDYVTSDGDVVSyvniSSVrvedggEYTCTATNDVG 86

Immunoglobulin (Ig)-like domain of human neurofascin (NF); member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the first immunoglobulin (Ig)-like domain of human neurofascin (NF). NF belongs to the L1 subfamily of cell adhesion molecules (CAMs) and is comprised of an extracellular region having six Ig-like domains and five fibronectin type III domains, a transmembrane region, and a cytoplasmic domain. NF has many alternatively spliced isoforms having different temporal expression patterns during development. NF participates in axon subcellular targeting and synapse formation, however little is known of the functions of the different isoforms. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lacks a C" strand.

Pssm-ID: 409459 Cd Length: 95 Bit Score: 38.42 E-value: 2.83e-03

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  426 MLSPRNQLIrvilynrtrLDCPFFGSPIPTLRWFKNGQGSNL--DGGNYHVYENGSLEIKMI---RKED-QGIYTCVATN 499
Cdd:cd05875     12 IVDPRDNIL---------IECEAKGNPVPTFHWTRNGKFFNVakDPRVSMRRRSGTLVIDFRgggRPEDyEGEYQCFARN 82

                           90
                   ....*....|...
gi 2217265369  500 ILGKA-ENQVRLE 511
Cdd:cd05875     83 KFGTAlSNKIRLQ 95

Second immunoglobulin (Ig)-like domain of Axl/Tyro3 family receptor tyrosine kinases (RTKs); member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the second immunoglobulin (Ig)-like domain in the Axl/Tyro3 family of receptor tyrosine kinases (RTKs). This family includes Axl (also known as Ark, Ufo, and Tyro7), Tyro3 (also known as Sky, Rse, Brt, Dtk, and Tif), and Mer (also known as Nyk, c-Eyk, and Tyro12). Axl/Tyro3 family receptors have an extracellular portion with two Ig-like domains followed by two fibronectin-types III (FNIII) domains, a membrane-spanning single helix, and a cytoplasmic tyrosine kinase domain. Axl, Tyro3, and Mer are widely expressed in adult tissues, though they show higher expression in the brain, lymphatic and vascular systems, and testis. Axl, Tyro3, and Mer bind the vitamin K dependent protein Gas6 with high affinity, and in doing so activate their tyrosine kinase activity. Axl/Gas6 signaling may play a part in cell adhesion processes, prevention of apoptosis, and cell proliferation.

Pssm-ID: 409407 Cd Length: 82 Bit Score: 38.22 E-value: 2.86e-03

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  332 YWLDEPKNLILAPGEDGRLVCRANGNPKP-TVQWMVNGEPLQSAP-PNPNrevagdtiIFRDTQISSRAVYQCNTSNEHG 409
Cdd:cd05749      1 HFTVEPEDLAVTANTPFNLTCQAVGPPEPvEILWWQGGSPLGGPPaPSPS--------VLNVPGLNETTKFSCEAHNAKG 72

Third immunoglobulin (Ig)-like domain of peroxidasin; The members here are composed of the third immunoglobulin (Ig)-like domain in peroxidasin. Peroxidasin has a peroxidase domain and interacting extracellular motifs containing four Ig-like domains. It has been suggested that peroxidasin is secreted and has functions related to the stabilization of the extracellular matrix. It may play a part in various other important processes such as removal and destruction of cells which have undergone programmed cell death and protection of the organism against non-self.

Pssm-ID: 143222 [Multi-domain] Cd Length: 74 Bit Score: 38.00 E-value: 2.90e-03

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 2217265369   57 CEAKGNPAPSFHWTRNSRffniakdpRVSMRRR-----SGTLvidfRSGGRPEEYEGEYQCFARNKFGT 120
Cdd:cd05745      9 CEAQGYPQPVIAWTKGGS--------QLSVDRRhlvlsSGTL----RISRVALHDQGQYECQAVNIVGS 65

Immunoglobulin (Ig)-like domain in neuregulins; The members here are composed of the immunoglobulin (Ig)-like domain in neuregulins (NRGs). NRGs are signaling molecules which participate in cell-cell interactions in the nervous system, breast, heart, and other organ systems, and are implicated in the pathology of diseases including schizophrenia, multiple sclerosis, and breast cancer. There are four members of the neuregulin gene family (NRG-1, NRG-2, NRG-3, and NRG-4). The NRG-1 protein, binds to and activates the tyrosine kinases receptors ErbB3 and ErbB4, initiating signaling cascades. The other NRGs proteins bind one or the other or both of these ErbBs. NRG-1 has multiple functions: in the brain it regulates various processes such as radial glia formation and neuronal migration, dendritic development, and expression of neurotransmitters receptors, while in the peripheral nervous system NRG-1 regulates processes such as target cell differentiation, and Schwann cell survival. There are many NRG-1 isoforms which arise from the alternative splicing of mRNA. Less is known of the functions of the other NRGs. NRG-2 and NRG-3 are expressed predominantly in the nervous system. NRG-2 is expressed by motor neurons and terminal Schwann cells, and is concentrated near synaptic sites and may be a signal that regulates synaptic differentiation. NRG-4 has been shown to direct pancreatic islet cell development towards the delta-cell lineage.

Pssm-ID: 409408 [Multi-domain] Cd Length: 92 Bit Score: 38.26 E-value: 3.25e-03

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  525 QVARRGTTVQLECR-VKHDPSLKLtvSWLKD------DEPLYIGNRMKKEDDSLTIFGVAERDQGSYTCVASTELDQDLA 597
Cdd:cd05750      9 QTVQEGSKLVLKCEaTSENPSPRY--RWFKDgkelnrKRPKNIKIRNKKKNSELQINKAKLEDSGEYTCVVENILGKDTV 86


                   ....*.
gi 2217265369  598 KAYLTV 603
Cdd:cd05750     87 TGNVTV 92

Immunoglobulin domain; This domain contains immunoglobulin-like domains.

Pssm-ID: 464026 [Multi-domain] Cd Length: 79 Bit Score: 37.76 E-value: 3.27e-03

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 2217265369  341 ILAPGEDGRLVCRANGNPKPTVQWMVNGEPLqsaPPNPNrevagdtIIFRDTQISSRAVYQCNTSNEHG 409
Cdd:pfam13895   10 VVTEGEPVTLTCSAPGNPPPSYTWYKDGSAI---SSSPN-------FFTLSVSAEDSGTYTCVARNGRG 68

First immunoglobulin (Ig) domain of contactin-1; member of the I-set of Ig superfamily domains; The members here are composed of the first immunoglobulin (Ig) domain of the neural cell adhesion molecule contactin-1. Contactins are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. Contactin-1 is differentially expressed in tumor tissues and may, through a RhoA mechanism, facilitate invasion and metastasis of human lung adenocarcinoma. This group belongs to the I-set of IgSF domains.

Pssm-ID: 409436 [Multi-domain] Cd Length: 95 Bit Score: 38.40 E-value: 3.30e-03

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|....
gi 2217265369  441 RTRLDCPFFGSPIPTLRWFKNGQGSNLDGGNYHVYeNGSLEIKMIRK-EDQGIYTCVATNILGK 503
Cdd:cd05849     21 KVSVNCRARANPFPIYKWRKNNLDIDLTNDRYSMV-GGNLVINNPDKyKDAGRYVCIVSNIYGK 83

Second immunoglobulin (Ig)-like domain in Robo (roundabout) receptors; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the second immunoglobulin (Ig)-like domain in Robo (roundabout) receptors. Robo receptors play a role in the development of the central nervous system (CNS), and are receptors of the Slit protein. Slit is a repellant secreted by the neural cells in the midline. Slit acts through Robo to prevent most neurons from crossing the midline from either side. Three mammalian Robo homologs (Robo1, Robo2, and Robo3), and three mammalian Slit homologs (Slit-1,Slit-2, Slit-3), have been identified. Commissural axons, which cross the midline, express low levels of Robo; longitudinal axons, which avoid the midline, express high levels of Robo. Robo1, Robo2, and Robo3 are expressed by commissural neurons in the vertebrate spinal cord and Slit-1, Slit-2, Slit-3 are expressed at the ventral midline. Robo-3 is a divergent member of the Robo family which instead of being a positive regulator of Slit responsiveness, antagonizes Slit responsiveness in precrossing axons. The Slit-Robo interaction is mediated by the second leucine-rich repeat (LRR) domain of Slit and the two N-terminal Ig domains of Robo, Ig1 and Ig2. The primary Robo binding site for Slit-2 has been shown by surface plasmon resonance experiments and mutational analysis to be the Ig1 domain, while the Ig2 domain has been proposed to harbor a weak secondary binding site. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409389 [Multi-domain] Cd Length: 87 Bit Score: 38.15 E-value: 3.34e-03

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369   47 VDPRDNI-------LIECEA-KGNPAPSFHWTRNSRFFNIaKDPRVSMRRrSGTLVIDfrsggRPEEY-EGEYQCFARNK 117
Cdd:cd05724      2 VEPSDTQvavgemaVLECSPpRGHPEPTVSWRKDGQPLNL-DNERVRIVD-DGNLLIA-----EARKSdEGTYKCVATNM 74

                           90
                   ....*....|...
gi 2217265369  118 FGTALSNRIRLQV 130
Cdd:cd05724     75 VGERESRAARLSV 87

Immunoglobulin (Ig)-like domain of human neurofascin (NF); member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the first immunoglobulin (Ig)-like domain of human neurofascin (NF). NF belongs to the L1 subfamily of cell adhesion molecules (CAMs) and is comprised of an extracellular region having six Ig-like domains and five fibronectin type III domains, a transmembrane region, and a cytoplasmic domain. NF has many alternatively spliced isoforms having different temporal expression patterns during development. NF participates in axon subcellular targeting and synapse formation, however little is known of the functions of the different isoforms. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lacks a C" strand.

Pssm-ID: 409459 Cd Length: 95 Bit Score: 38.03 E-value: 3.51e-03

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  338 KNLILAPGEDGRLVCRANGNPKPTVQWMVNGEPLQSA--PPNPNREVAGDTIIfrDTQISSR-----AVYQCNTSNEHGY 410
Cdd:cd05875      9 KDYIVDPRDNILIECEAKGNPVPTFHWTRNGKFFNVAkdPRVSMRRRSGTLVI--DFRGGGRpedyeGEYQCFARNKFGT 86


                   ....
gi 2217265369  411 LLAN 414
Cdd:cd05875     87 ALSN 90

Immunoglobulin domain; This domain contains immunoglobulin-like domains.

Pssm-ID: 464026 [Multi-domain] Cd Length: 79 Bit Score: 37.76 E-value: 3.67e-03

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 2217265369  522 PEDQVARRGTTVQLECRVKHDPSLKltVSWLKDDEPLyignrmkKEDDSLTIFGVAERDQGSYTCVAS 589
Cdd:pfam13895    6 PSPTVVTEGEPVTLTCSAPGNPPPS--YTWYKDGSAI-------SSSPNFFTLSVSAEDSGTYTCVAR 64

Immunoglobulin-like domain of human Aortic Preferentially Expressed Protein-1 (APEG-1) and similar proteins; a member of the I-set of IgSF domains; The members here are composed of the immunoglobulin I-set (IgI) domain of the Human Aortic Preferentially Expressed Protein-1 (APEG-1) and similar proteins. APEG-1 is a novel specific smooth muscle differentiation marker predicted to play a role in the growth and differentiation of arterial smooth muscle cells (SMCs). The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structure of the human APEG-1 lacks this strand and thus it belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409567 Cd Length: 91 Bit Score: 38.22 E-value: 3.70e-03

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 2217265369  450 GSPIPTLRWFKNGQGSNLDGGNY-HVYENGSLEIKMIRKE--DQGIYTCVATNILGKAENQVRLEV 512
Cdd:cd20975     26 GEPKPVVSWLRNRQPVRPDQRRFaEEAEGGLCRLRILAAErgDAGFYTCKAVNEYGARQCEARLEV 91

Immunoglobulin (Ig)-like domain of human neurofascin (NF); member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the first immunoglobulin (Ig)-like domain of human neurofascin (NF). NF belongs to the L1 subfamily of cell adhesion molecules (CAMs) and is comprised of an extracellular region having six Ig-like domains and five fibronectin type III domains, a transmembrane region, and a cytoplasmic domain. NF has many alternatively spliced isoforms having different temporal expression patterns during development. NF participates in axon subcellular targeting and synapse formation, however little is known of the functions of the different isoforms. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lacks a C" strand.

Pssm-ID: 409459 Cd Length: 95 Bit Score: 38.03 E-value: 3.80e-03

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 2217265369  257 DLLLECIASGVPTPDIAWYKKGgdlpsdkaKFENFNKALRITNVS---------------EEDSGEYFCLASNKMGS 318
Cdd:cd05875     18 NILIECEAKGNPVPTFHWTRNG--------KFFNVAKDPRVSMRRrsgtlvidfrgggrpEDYEGEYQCFARNKFGT 86

First immunoglobulin-like domains A168 within the A-band segment of human cardiac titin, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the first immunoglobulin-like domain A168 within the A-band segment of human cardiac titin. Titin is a key component in the assembly and functioning of vertebrate striated muscles. By providing connections at the level of individual microfilaments, it contributes to the fine balance of forces between the two halves of the sarcomere. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structures of the titin-A168169 lacks this strand and thus it belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409563 Cd Length: 93 Bit Score: 38.22 E-value: 3.80e-03

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 2217265369  255 GMDLLLECIASGVPTPDIAWYKKGGDLPSDKAKFENFNK----ALRITNVS-EEDSGEYFCLASNKMGS 318
Cdd:cd20971     16 QSNATLVCKVTGHPKPIVKWYRQGKEIIADGLKYRIQEFkggyHQLIIASVtDDDATVYQVRATNQGGS 84

CH3 domain (third constant Ig domain of the heavy chain) in immunoglobulin heavy alpha, gamma, and delta chains, and CH4 domain (fourth constant Ig domain of the heavy chain) in immunoglobulin heavy alpha, epsilon, and mu chains; member of the C1-set of I; The members here are composed of the third and fourth immunoglobulin constant domain (IgC) of alpha, delta, gamma and alpha, epsilon, and mu heavy chains, respectively. This domain is found on the Fc fragment. The basic structure of Ig molecules is a tetramer of two light chains and two heavy chains linked by disulfide bonds. There are two types of light chains: kappa and lambda; each is composed of a constant domain and a variable domain. There are five types of heavy chains: alpha, delta, epsilon, gamma, and mu, all consisting of a variable domain (VH) with three (alpha, delta and gamma) or four (epsilon and mu) constant domains (CH1 to CH4). Ig molecules are modular proteins, in which the variable and constant domains have clear, conserved sequence patterns.

Pssm-ID: 409425 Cd Length: 105 Bit Score: 38.09 E-value: 4.54e-03

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  522 PEDQVARRgTTVQLECRVK-HDPSlKLTVSWLKDDEPL----YIGNRMKKEDDS-------LTIfGVAERDQG-SYTCVA 588
Cdd:cd05768      9 PEEELSLN-ETVTLTCLVKgFYPE-DIFVSWLQNGEPLpsadYKTTAPVPESDGsffvyskLNV-STADWNSGdVFSCVV 85


                   ...
gi 2217265369  589 STE 591
Cdd:cd05768     86 GHE 88

Immunoglobulin (Ig)-like I-set domain of Neural Cell Adhesion Molecule 1 (NCAM-1) and similar proteins; The members here are composed of the fourth immunoglobulin (Ig)-like domain of Neural Cell Adhesion Molecule (NCAM-1). NCAM plays important roles in the development and regeneration of the central nervous system, in synaptogenesis and neural migration. NCAM mediates cell-cell and cell-substratum recognition and adhesion via homophilic (NCAM-NCAM), and heterophilic (NCAM-non-NCAM), interactions. NCAM is expressed as three major isoforms having different intracellular extensions. The extracellular portion of NCAM has five N-terminal Ig-like domains and two fibronectin type III domains. The double zipper adhesion complex model for NCAM homophilic binding involves Ig1, Ig2, and Ig3. By this model, Ig1 and Ig2 mediate dimerization of NCAM molecules situated on the same cell surface (cis interactions), and Ig3 domains mediate interactions between NCAM molecules expressed on the surface of opposing cells (trans interactions), through binding to the Ig1 and Ig2 domains. The adhesive ability of NCAM is modulated by the addition of polysialic acid chains to the fifth Ig-like domain. Also included in this group is NCAM-2 (also known as OCAM/mamFas II and RNCAM) NCAM-2 is differentially expressed in the developing and mature olfactory epithelium (OE). One of the unique features of I-set domains is the lack of a C" strand. The structures of this group show that the Ig domain lacks this strand and thus is a member of the I-set of Ig domains.

Pssm-ID: 409395 [Multi-domain] Cd Length: 96 Bit Score: 37.89 E-value: 4.87e-03

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 2217265369   51 DNILIECEAKGNPAPSFHWTRNSR-FFNIAKDP--RVSMRRRSG----TLV-IDFRSGGRpeeyegeYQCFARNKFG 119
Cdd:cd05732     17 EQITLTCEAEGDPIPEITWRRATRgISFEEGDLdgRIVVRGHARvsslTLKdVQLTDAGR-------YDCEASNRIG 86

Fourth immunoglobulin domain of the Drosophila melanogaster Dscam protein, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the fourth immunoglobulin domain of the Drosophila melanogaster Down syndrome cell adhesion molecule (DSCAM) protein and similar proteins. Down syndrome cell adhesion molecule (DSCAM) is a cell adhesion molecule that plays critical roles in neural development, including axon guidance and branching, axon target recognition, self-avoidance and synaptic formation. DSCAM belongs to the immunoglobulin superfamily and contributes to defects in the central nervous system in Down syndrome patients. Vertebrate DSCAMs differ from Drosophila Dscam1 in that they lack the extensive alternative splicing that occurs in the insect gene. Drosophila melanogaster Dscam has 38,016 isoforms generated by the alternative splicing of four variable exon clusters, which allows every neuron in the fly to display a distinctive set of Dscam proteins on its cell surface. Drosophila Dscam1 is a cell-surface protein that plays important roles in neural development and axon tiling of neurons. It is shown that thousands of isoforms bind themselves through specific homophilic (self-binding) interactions, a process which mediates cellular self-recognition. Drosophila Dscam2 is also alternatively spliced and plays a key role in the development of two visual system neurons, monopolar cells L1 and L2. This group is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand.

Pssm-ID: 409548 [Multi-domain] Cd Length: 96 Bit Score: 37.54 E-value: 5.26e-03

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369   34 PPTItKQSAKDHIVDPRDNILIECEAKGNPAPSFHWTRNSrfFNIAKDPRVSM---RRRSGTLV----IdfrSGGRPEEy 106
Cdd:cd20956      1 APVL-LETFSEQTLQPGPSVSLKCVASGNPLPQITWTLDG--FPIPESPRFRVgdyVTSDGDVVsyvnI---SSVRVED- 73

                           90       100
                   ....*....|....*....|....
gi 2217265369  107 EGEYQCFARNKFGTAlSNRIRLQV 130
Cdd:cd20956     74 GGEYTCTATNDVGSV-SHSARINV 96

Third immunoglobulin (Ig)-like domain of peroxidasin; The members here are composed of the third immunoglobulin (Ig)-like domain in peroxidasin. Peroxidasin has a peroxidase domain and interacting extracellular motifs containing four Ig-like domains. It has been suggested that peroxidasin is secreted and has functions related to the stabilization of the extracellular matrix. It may play a part in various other important processes such as removal and destruction of cells which have undergone programmed cell death and protection of the organism against non-self.

Pssm-ID: 143222 [Multi-domain] Cd Length: 74 Bit Score: 36.84 E-value: 5.76e-03

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 2217265369  530 GTTVQLECRVKHDPslKLTVSWLKDDEPLYIGNR-MKKEDDSLTIFGVAERDQGSYTCVASTELDQDLAKAYLTV 603
Cdd:cd05745      2 GQTVDFLCEAQGYP--QPVIAWTKGGSQLSVDRRhLVLSSGTLRISRVALHDQGQYECQAVNIVGSQRTVAQLTV 74

Fifth immunoglobulin domain of the Drosophila melanogaster Dscam protein, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the fifth immunoglobulin domain of the Drosophila melanogaster Down syndrome cell adhesion molecule (DSCAM) protein and similar proteins. Down syndrome cell adhesion molecule (DSCAM) is a cell adhesion molecule that plays critical roles in neural development, including axon guidance and branching, axon target recognition, self-avoidance and synaptic formation. DSCAM belongs to the immunoglobulin superfamily and contributes to defects in the central nervous system in Down syndrome patients. Vertebrate DSCAMs differ from Drosophila Dscam1 in that they lack the extensive alternative splicing that occurs in the insect gene. Drosophila melanogaster Dscam has 38,016 isoforms generated by the alternative splicing of four variable exon clusters, which allows every neuron in the fly to display a distinctive set of Dscam proteins on its cell surface. Drosophila Dscam1 is a cell-surface protein that plays important roles in neural development and axon tiling of neurons. It is shown that thousands of isoforms bind themselves through specific homophilic (self-binding) interactions, a process which mediates cellular self-recognition. Drosophila Dscam2 is also alternatively spliced and plays a key role in the development of two visual system neurons, monopolar cells L1 and L2. This group is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand.

Pssm-ID: 409550 [Multi-domain] Cd Length: 89 Bit Score: 37.16 E-value: 5.97e-03

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|.
gi 2217265369  530 GTTVQLECRVKHDPsLKlTVSWLKDDEPLYIGNRMK-KEDDSLTIFGV-AERDQGSYTCVA 588
Cdd:cd20958     15 GQTLRLHCPVAGYP-IS-SITWEKDGRRLPLNHRQRvFPNGTLVIENVqRSSDEGEYTCTA 73

Immunoglobulin (Ig)-like domain of vascular endothelial growth factor receptor 2 (VEGFR-2); member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the immunoglobulin (Ig)-like domain of vascular endothelial growth factor receptor 2 (VEGFR-2). The VEGFRs have an extracellular component with seven Ig-like domains, a transmembrane segment, and an intracellular tyrosine kinase domain interrupted by a kinase-insert domain. VEGFRs bind VEGFs with high affinity at the Ig-like domains. VEGFR-2 (KDR/Flk-1) is a major mediator of the mitogenic, angiogenic and microvascular permeability-enhancing effects of VEGF-A; VEGF-A is important to the growth and maintenance of vascular endothelial cells and to the development of new blood- and lymphatic-vessels in physiological and pathological states. VEGF-A also interacts with VEGFR-1, which it binds more strongly than VEGFR-2. VEGFR-1 and VEGFR-2 may mediate a chemotactic and a survival signal in hematopoietic stem cells or leukemia cells. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409450 Cd Length: 89 Bit Score: 37.21 E-value: 6.08e-03

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|....
gi 2217265369  266 GVPTPDIAWYKKGGDLPSDKAKFENFnkALRITNVSEEDSGEYFCLASNKMGSI--RHTISVRV 327
Cdd:cd05864     28 GYPPPEIKWYKNGIPIESNHTIKAGH--VLTIMEVTEKDAGNYTVVLTNPISKEkqRHTFSLVV 89

agrin-responsive second immunoglobulin-like domains (Ig2) of the Muscle-specific kinase (MuSK) ectodomain; a member of the I-set of Ig superfamily domains; The members here are composed of the second immunoglobulin-like (Ig) domains of the Muscle-specific kinase (MuSK) ectodomain. MuSK is a receptor tyrosine kinase specifically expressed in skeletal muscle, where it plays a central role in the formation and maintenance of the neuromuscular junction (NMJ). MuSK is activated by agrin, a neuron-derived heparan sulfate proteoglycan. The activation of MUSK in myotubes regulates the formation of NMJs through the regulation of different processes including the specific expression of genes in subsynaptic nuclei, the reorganization of the actin cytoskeleton and the clustering of the acetylcholine receptors (AChR) in the postsynaptic membrane. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structure of the MuSK lacks this strand and thus it belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409560 [Multi-domain] Cd Length: 88 Bit Score: 37.22 E-value: 6.52e-03

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 2217265369  517 RIYRMPEDQVARRGTTVQLECRVKHDPslKLTVSWLKDDEPLYIGNRMKK-EDDSLTIFGVAERDQGSYTCVASTEL 592
Cdd:cd20968      1 KITRPPTNVTIIEGLKAVLPCTTMGNP--KPSVSWIKGDDLIKENNRIAVlESGSLRIHNVQKEDAGQYRCVAKNSL 75

Fifth immunoglobulin (Ig) domain of contactin-1; The members here are composed of the fifth immunoglobulin (Ig) domain of the neural cell adhesion molecule contactin-1. Contactins are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. Contactin-1 is differentially expressed in tumor tissues and may through a RhoA mechanism, facilitate invasion and metastasis of human lung adenocarcinoma.

Pssm-ID: 409438 Cd Length: 89 Bit Score: 37.29 E-value: 6.71e-03

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  254 RGMDLLLECIASGVPTPDIAWyKKGGDLPSDKAKFENFNK-ALRITNVSEEDSGEYFCLASNKMGSIRHT 322
Cdd:cd05852     16 KGGRVIIECKPKAAPKPKFSW-SKGTELLVNNSRISIWDDgSLEILNITKLDEGSYTCFAENNRGKANST 84

Second immunoglobulin (Ig)-like domain of interleukin-1 receptor (IL1R), and similar domains; The members here are composed of the second immunoglobulin (Ig)-like domain of interleukin-1 receptor (IL1R; also known as cluster of differentiation (CD) 121). IL-1 alpha and IL-1 beta are cytokines which participate in the regulation of inflammation, immune responses, and hematopoiesis. These cytokines bind to the IL-1 receptor type 1 (IL1R1), which is activated on additional association with interleukin-1 receptor accessory protein (IL1RAP). IL-1 also binds a second receptor designated type II (IL1R2). Mature IL1R1 consists of three IG-like domains, a transmembrane domain, and a large cytoplasmic domain. Mature IL1R2 is organized similarly except that it has a short cytoplasmic domain. The latter does not initiate signal transduction. A naturally occurring cytokine IL-1RA (IL-1 receptor antagonist) is widely expressed and binds to IL-1 receptors, inhibiting the binding of IL-1 alpha and IL-1 beta. This group also contains ILIR-like 1 (IL1R1L) which maps to the same chromosomal location as IL1R1 and IL1R2.

Pssm-ID: 409415 Cd Length: 92 Bit Score: 37.30 E-value: 6.98e-03

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 2217265369  429 PRNQLIRVILYNRtRLDCP-----FFGSPIPTLRWFKNGQGsnLDGGNYHVYENGSLEIKMIRKEDQGIYTCVAT 498
Cdd:cd05757      1 PRYKQKLPITKGG-KITCPdlddyKNENVLPPIQWYKDCKP--LQGDKRFIPKGSKLLIQNVTEEDAGNYTCKFT 72

Immunoglobulin domain; Members of the immunoglobulin superfamily are found in hundreds of proteins of different functions. Examples include antibodies, the giant muscle kinase titin and receptor tyrosine kinases. Immunoglobulin-like domains may be involved in protein-protein and protein-ligand interactions.

Pssm-ID: 395002 Cd Length: 86 Bit Score: 37.17 E-value: 7.30e-03

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 2217265369  143 PVVVQEGAPLTLQCNPPPGLPSPVIFWMSSSMEPITQDKRV---SQGHNGDLYFSNVMLQDMQTdYSCNARFH 212
Cdd:pfam00047    5 TVTVLEGDSATLTCSASTGSPGPDVTWSKEGGTLIESLKVKhdnGRTTQSSLLISNVTKEDAGT-YTCVVNNP 76

Second immunoglobulin (Ig)-like domain of interleukin-1 receptor (IL1R), and similar domains; The members here are composed of the second immunoglobulin (Ig)-like domain of interleukin-1 receptor (IL1R; also known as cluster of differentiation (CD) 121). IL-1 alpha and IL-1 beta are cytokines which participate in the regulation of inflammation, immune responses, and hematopoiesis. These cytokines bind to the IL-1 receptor type 1 (IL1R1), which is activated on additional association with interleukin-1 receptor accessory protein (IL1RAP). IL-1 also binds a second receptor designated type II (IL1R2). Mature IL1R1 consists of three IG-like domains, a transmembrane domain, and a large cytoplasmic domain. Mature IL1R2 is organized similarly except that it has a short cytoplasmic domain. The latter does not initiate signal transduction. A naturally occurring cytokine IL-1RA (IL-1 receptor antagonist) is widely expressed and binds to IL-1 receptors, inhibiting the binding of IL-1 alpha and IL-1 beta. This group also contains ILIR-like 1 (IL1R1L) which maps to the same chromosomal location as IL1R1 and IL1R2.

Pssm-ID: 409415 Cd Length: 92 Bit Score: 36.92 E-value: 7.85e-03

                           10        20        30        40
                   ....*....|....*....|....*....|....*....|....*...
gi 2217265369  542 DPSLKLTVSWLKDDEPLYIGNRMKKEDDSLTIFGVAERDQGSYTCVAS 589
Cdd:cd05757     25 NENVLPPIQWYKDCKPLQGDKRFIPKGSKLLIQNVTEEDAGNYTCKFT 72

Fourth immunoglobulin (Ig)-like domain in Robo (roundabout) receptors; member of the I-set of Ig superfamily (IgSF) domains; Members here are composed the fourth immunoglobulin (Ig)-like domain in Robo (roundabout) receptors. Robo receptors play a role in the development of the central nervous system (CNS), and are receptors of Slit protein. Slit is a repellant secreted by the neural cells in the midline. Slit acts through Robo to prevent most neurons from crossing the midline from either side. Three mammalian Robo homologs (Robo1, Robo2, Robo3), and three mammalian Slit homologs (Slit-1, Slit-2, Slit-3), have been identified. Commissural axons, which cross the midline, express low levels of Robo; longitudinal axons, which avoid the midline, express high levels of Robo. Robo1, Robo2, and Robo3 are expressed by commissural neurons in the vertebrate spinal cord and Slit-1, Slit-2, and Slit-3 are expressed at the ventral midline. Robo-3 is a divergent member of the Robo family which instead of being a positive regulator of Slit responsiveness, antagonizes Slit responsiveness in precrossing axons. The Slit-Robo interaction is mediated by the second leucine-rich repeat (LRR) domain of Slit and the two N-terminal Ig domains of Robo, Ig1 and Ig2. The primary Robo binding site for Slit2 has been shown by surface plasmon resonance experiments and mutational analysis to be the Ig1 domain, while the Ig2 domain has been proposed to harbor a weak secondary binding site. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409391 [Multi-domain] Cd Length: 98 Bit Score: 37.24 E-value: 9.42e-03

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217265369  522 PEDQVARRGTTVQLECRVKHDPslKLTVSWLKD--------DEPLYIGNRMK-KEDDSLTIFGVAERDQGSYTCVASTEL 592
Cdd:cd05726      6 PRDQVVALGRTVTFQCETKGNP--QPAIFWQKEgsqnllfpYQPPQPSSRFSvSPTGDLTITNVQRSDVGYYICQALNVA 83

                           90
                   ....*....|.
gi 2217265369  593 DQDLAKAYLTV 603
Cdd:cd05726     84 GSILAKAQLEV 94

Second immunoglobulin domain of the Drosophila melanogaster Dscam protein, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the second immunoglobulin domain of the Drosophila melanogaster Down syndrome cell adhesion molecule (DSCAM) protein and similar proteins. DSCAM is a cell adhesion molecule that plays critical roles in neural development, including axon guidance and branching, axon target recognition, self-avoidance and synaptic formation. DSCAM belongs to the immunoglobulin superfamily and contributes to defects in the central nervous system in Down syndrome patients. Vertebrate DSCAMs differ from Drosophila Dscam1 in that they lack the extensive alternative splicing that occurs in the insect gene. Drosophila melanogaster Dscam has 38,016 isoforms generated by the alternative splicing of four variable exon clusters, which allows every neuron in the fly to display a distinctive set of Dscam proteins on its cell surface. Drosophila Dscam1 is a cell-surface protein that plays important roles in neural development and axon tiling of neurons. It is shown that thousands of isoforms bind themselves through specific homophilic (self-binding) interactions, a process which mediates cellular self-recognition. Drosophila Dscam2 is also alternatively spliced and plays a key role in the development of two visual system neurons, monopolar cells L1 and L2. This group is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand.

Pssm-ID: 409545 Cd Length: 95 Bit Score: 36.75 E-value: 9.78e-03

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 2217265369  257 DLLLECIASGVPTPDIAWYK-------KGGDLPSDKAKfeNFNKALRITNVSEEDSGEYFCLASNKMG 317
Cdd:cd20953     20 SIALLCPAQGYPAPSFRWYKfiegttrKQAVVLNDRVK--QVSGTLIIKDAVVEDSGKYLCVVNNSVG 85