NCBI Conserved Domain Search

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: 172.73 E-value: 9.94e-51

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 127 PKIEVQFPETLPAAKGSTVKLECFALGNPVPQINWRRTDGMPFPSKIkLRKSNGMIEIPNFQQEDAGLYECITENSRGKN 206
Cdd:cd04968     1 PSIKVRFPADTYALKGQTVTLECFALGNPVPQIKWRKVDGSPSSQWE-ITTSEPVLEIPNVQFEDEGTYECEAENSRGKD 79


                  ....*....
gi 2024455041 207 IARGRLTYY 215
Cdd:cd04968    80 TVQGRIIVQ 88

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: 168.27 E-value: 6.51e-49

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 398 EPTRIILAPSNMDVTVGESVILPCQVQHDPILDISFTWYFNGTLTDFKKDASHFEKVGGSAS-GDLMIRNIQLKHSGKYV 476
Cdd:cd05853     1 DPTRVMVPPSSMDVTVGESIVLPCQVSHDHSLDIVFTWSFNGHLIDFQKDGDHFERVGGQDSaGDLMIRSIQLKHAGKYV 80

                          90       100
                  ....*....|....*....|..
gi 2024455041 477 CMVKTEVDSVASAADLIVRGSP 498
Cdd:cd05853    81 CMVQTSVDKLSAAADLIVRGPP 102

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: 153.09 E-value: 1.55e-43

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 398 EPTRIILAPSNMDVTVGESVILPCQVQHDPILDISFTWYFNGTLTDFKKDASHFEKVGG-SASGDLMIRNIQLKHSGKYV 476
Cdd:cd04970     1 DATRITLAPSNADITVGENATLQCHASHDPTLDLTFTWSFNGVPIDLEKIEGHYRRRYGkDSNGDLEIVNAQLKHAGRYT 80

                          90       100
                  ....*....|....*....|..
gi 2024455041 477 CMVKTEVDSVASAADLIVRGSP 498
Cdd:cd04970    81 CTAQTVVDSDSASATLVVRGPP 102

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: 141.58 E-value: 9.81e-40

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 220 WIQMIKDTEIAVEDTLYWDCRASGKPKPSYRWLKNGEQLSVEGRIQIENGALTISSLNLTDSGRYQCIAENKHGVIYSSA 299
Cdd:cd05728     2 WLKVISDTEADIGSSLRWECKASGNPRPAYRWLKNGQPLASENRIEVEAGDLRITKLSLSDSGMYQCVAENKHGTIYASA 81


                  ....
gi 2024455041 300 ELRV 303
Cdd:cd05728    82 ELAV 85

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: 127.19 E-value: 1.17e-34

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 308 PDFSKNPMKKMIQVQIGSTVDFECKPKASPKARCSWKKGGEQLHENERITLLKDGGLRITNVTKVDAGSYTCVATNQFGT 387
Cdd:cd04969     1 PDFELNPVKKKILAAKGGDVIIECKPKASPKPTISWSKGTELLTNSSRICILPDGSLKIKNVTKSDEGKYTCFAVNFFGK 80


                  ....*....
gi 2024455041 388 ASGTTNLVV 396
Cdd:cd04969    81 ANSTGSLSV 89

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: 117.45 E-value: 5.00e-31

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 398 EPTRIILAPSNMDVTVGESVILPCQVQHDPILDISFTWYFNGTLTDFKKDASHFEKVGGSAS-GDLMIRNIQLKHSGKYV 476
Cdd:cd05854     1 DATKITLAPSSADINQGENLTLQCHASHDPTMDLTFTWSLDDFPIDLDKPNGHYRRMEVKETiGDLVIVNAQLSHAGTYT 80

                          90       100
                  ....*....|....*....|..
gi 2024455041 477 CMVKTEVDSVASAADLIVRGSP 498
Cdd:cd05854    81 CTAQTVVDSASASATLVVRGPP 102

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: 102.65 E-value: 4.00e-26

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041  29 RSTVSVREGQGVVLLCGTPPRAGELSFAWIFNEYPSFVQEDSRRFVSQETGHLYIAKVEPSDVGNYTCVVTSTVTNSQVL 108
Cdd:cd05727     2 RDEVKVKEGWGVVLFCDPPPHYPDLSYRWLLNEFPNFIPEDGRRFVSQTNGNLYIAKVEASDRGNYSCFVSSPSSTKSVF 81


                  ....*.
gi 2024455041 109 GSPTPL 114
Cdd:cd05727    82 SKFIPL 87

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: 98.15 E-value: 1.69e-24

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 308 PDFSKNPMKKMIQVQIGSTVDFECKPKASPKARCSWKKGGEQLHENERITLLKDGGLRITNVTKVDAGSYTCVATNQFGT 387
Cdd:cd05852     1 PTFEFNPMKKKILAAKGGRVIIECKPKAAPKPKFSWSKGTELLVNNSRISIWDDGSLEILNITKLDEGSYTCFAENNRGK 80


                  ....*....
gi 2024455041 388 ASGTTNLVV 396
Cdd:cd05852    81 ANSTGVLSV 89

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: 88.15 E-value: 4.66e-21

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 127 PKIEVQFPETLpAAKGSTVKLECFALGNPVPQINWRRTDgMPFPSKIKLRKSNGMIEIPNFQQEDAGLYECITENSRGKN 206
Cdd:cd05851     2 ADINVKFKDTY-ALKGQNVTLECFALGNPVPVIRWRKIL-EPMPATAEISMSGAVLKIFNIQPEDEGTYECEAENIKGKD 79


                  ....*.
gi 2024455041 207 IARGRL 212
Cdd:cd05851    80 KHQARV 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: 83.70 E-value: 2.33e-19

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 498 PGPPEHVRVDEITDTTAQISWQEGTDNHSPVTAYTIQARTPFSVGWQRVTTVPdvidGNTFTTTVVDLNPWVEYEFRVVA 577
Cdd:cd00063     1 PSPPTNLRVTDVTSTSVTLSWTPPEDDGGPITGYVVEYREKGSGDWKEVEVTP----GSETSYTLTGLKPGTEYEFRVRA 76

                          90
                  ....*....|....*...
gi 2024455041 578 SNKIGGGEPSlPSEKVRT 595
Cdd:cd00063    77 VNGGGESPPS-ESVTVTT 93

Immunoglobulin I-set domain;

Pssm-ID: 400151 [Multi-domain] Cd Length: 90 Bit Score: 82.69 E-value: 4.36e-19

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 308 PDFSKNPmkKMIQVQIGSTVDFECKPKASPKARCSWKKGGEQLHENERITLLKDGG---LRITNVTKVDAGSYTCVATNQ 384
Cdd:pfam07679   1 PKFTQKP--KDVEVQEGESARFTCTVTGTPDPEVSWFKDGQPLRSSDRFKVTYEGGtytLTISNVQPDDSGKYTCVATNS 78

                          90
                  ....*....|..
gi 2024455041 385 FGTASGTTNLVV 396
Cdd:pfam07679  79 AGEAEASAELTV 90

Immunoglobulin I-set domain;

Pssm-ID: 400151 [Multi-domain] Cd Length: 90 Bit Score: 77.68 E-value: 2.98e-17

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 218 PHWIQMIKDTEIAVEDTLYWDCRASGKPKPSYRWLKNGEQLSVEGRIQIEN----GALTISSLNLTDSGRYQCIAENKHG 293
Cdd:pfam07679   1 PKFTQKPKDVEVQEGESARFTCTVTGTPDPEVSWFKDGQPLRSSDRFKVTYeggtYTLTISNVQPDDSGKYTCVATNSAG 80

                          90
                  ....*....|
gi 2024455041 294 VIYSSAELRV 303
Cdd:pfam07679  81 EAEASAELTV 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: 76.78 E-value: 5.03e-17

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041  319 IQVQIGSTVDFECKPKASPKARCSWKK-GGEQLHENERITLLKDGG---LRITNVTKVDAGSYTCVATNQFGTASGTTNL 394
Cdd:smart00410   4 VTVKEGESVTLSCEASGSPPPEVTWYKqGGKLLAESGRFSVSRSGStstLTISNVTPEDSGTYTCAATNSSGSASSGTTL 83


                   ..
gi 2024455041  395 VV 396
Cdd:smart00410  84 TV 85

Fibronectin type III domain;

Pssm-ID: 394996 [Multi-domain] Cd Length: 85 Bit Score: 76.30 E-value: 6.02e-17

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 499 GPPEHVRVDEITDTTAQISWQEGTDNHSPVTAYTIQARTPFSVGWQRVTTVPdvidGNTFTTTVVDLNPWVEYEFRVVAS 578
Cdd:pfam00041   1 SAPSNLTVTDVTSTSLTVSWTPPPDGNGPITGYEVEYRPKNSGEPWNEITVP----GTTTSVTLTGLKPGTEYEVRVQAV 76


                  ....*....
gi 2024455041 579 NKIGGGEPS 587
Cdd:pfam00041  77 NGGGEGPPS 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: 75.12 E-value: 2.06e-16

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 218 PHWIQMI-KDTEIAVEDTLYWDCRASGKPKPSYRWLKNGEQLSVE-GRIQIENGALTISSLNLTDSGRYQCIAENKHGVI 295
Cdd:cd20978     1 PKFIQKPeKNVVVKGGQDVTLPCQVTGVPQPKITWLHNGKPLQGPmERATVEDGTLTIINVQPEDTGYYGCVATNEIGDI 80


                  ....*...
gi 2024455041 296 YSSAELRV 303
Cdd:cd20978    81 YTETLLHV 88

Fibronectin type 3 domain [General function prediction only];

Pssm-ID: 442628 [Multi-domain] Cd Length: 603 Bit Score: 83.51 E-value: 2.18e-16

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 506 VDEITDTTAQISWQEGTDNHSPVTAYTIQARTPFSVGWQRVTTVPDVIDGNTFTTTVVDLNPWVEYEFRVVASNKIGGge 585
Cdd:COG3401    42 VVLSVTTKESPGTLLVAAGLSSGGGLGTGGRAGTTSGVAAVAVAAAPPTATGLTTLTGSGSVGGATNTGLTSSDEVPS-- 119

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 586 PSLPSEKVRTEEAVPEIPPAEVSGGGGSRSELVITWDPIPEELQNGEGFGYVVAFRPFGTTTWIQTVVTSPDTPRYVFRN 665
Cdd:COG3401   120 PAVGTATTATAVAGGAATAGTYALGAGLYGVDGANASGTTASSVAGAGVVVSPDTSATAAVATTSLTVTSTTLVDGGGDI 199

                         170       180       190       200       210       220       230       240
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 666 EsilPFSPYEVKVGVYNNKGEGPFSSITTVFSAEEEPTvAPSGVSVTSLSSSVIEVSWKAIPwkmsSGRLLGYEVRYWNN 745
Cdd:COG3401   200 E---PGTTYYYRVAATDTGGESAPSNEVSVTTPTTPPS-APTGLTATADTPGSVTLSWDPVT----ESDATGYRVYRSNS 271

                         250       260       270       280       290       300       310       320
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 746 GGkeESSNRVkAAGNETSIRITGLKSNLAYYTAVRAYNSAG-AGPFSATVNATTKKTPPSQPPGNVVWNVTDSRVILNWE 824
Cdd:COG3401   272 GD--GPFTKV-ATVTTTSYTDTGLTNGTTYYYRVTAVDAAGnESAPSNVVSVTTDLTPPAAPSGLTATAVGSSSITLSWT 348

                         330       340       350       360       370       380
                  ....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 825 EVrameNESEVTGYKVLYRTSGQNNMNVLNTDKTTAELL---LPFNEDYIIEVKATTEGG 881
Cdd:COG3401   349 AS----SDADVTGYNVYRSTSGGGTYTKIAETVTTTSYTdtgLTPGTTYYYKVTAVDAAG 404

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: 71.65 E-value: 3.72e-15

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 308 PDFSKNPMKKMIQVQiGSTVDFECKPKASPKARCSWKKGGEQLHENERITLLKDGGLRITNVTKVDAGSYTCVATNQFGT 387
Cdd:cd20978     1 PKFIQKPEKNVVVKG-GQDVTLPCQVTGVPQPKITWLHNGKPLQGPMERATVEDGTLTIINVQPEDTGYYGCVATNEIGD 79


                  ....*....
gi 2024455041 388 ASGTTNLVV 396
Cdd:cd20978    80 IYTETLLHV 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: 70.60 E-value: 8.20e-15

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 308 PDFSKNPMKKmiQVQIGSTVDFECKPKASPKARCSWKKGGEQLHENERITLLKDGG----LRITNVTKVDAGSYTCVATN 383
Cdd:cd05744     1 PHFLQAPGDL--EVQEGRLCRFDCKVSGLPTPDLFWQLNGKPVRPDSAHKMLVRENgrhsLIIEPVTKRDAGIYTCIARN 78

                          90
                  ....*....|...
gi 2024455041 384 QFGTASGTTNLVV 396
Cdd:cd05744    79 RAGENSFNAELVV 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: 68.68 E-value: 3.53e-14

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 218 PHWIQMIKDTEIAVEDTLYWDCRASGKPKPSYRWLKNGEQLSVEGRIQI---ENG--ALTISSLNLTDSGRYQCIAENKH 292
Cdd:cd05744     1 PHFLQAPGDLEVQEGRLCRFDCKVSGLPTPDLFWQLNGKPVRPDSAHKMlvrENGrhSLIIEPVTKRDAGIYTCIARNRA 80

                          90
                  ....*....|.
gi 2024455041 293 GVIYSSAELRV 303
Cdd:cd05744    81 GENSFNAELVV 91

Fibronectin type 3 domain [General function prediction only];

Pssm-ID: 442628 [Multi-domain] Cd Length: 603 Bit Score: 76.19 E-value: 4.61e-14

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 456 GSASGDLMIRNIQLKHSGKYVCMVKTEVDSVASAADLIVRGS-----PGPPEHVRVDEITDTTAQISWQEGTDNHspVTA 530
Cdd:COG3401   186 TVTSTTLVDGGGDIEPGTTYYYRVAATDTGGESAPSNEVSVTtpttpPSAPTGLTATADTPGSVTLSWDPVTESD--ATG 263

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 531 YTIQARTPFSVGWQRVTTVpdviDGNTFTTTVVDLNpwVEYEFRVVASNkiGGGEPSLPSEKVR-TEEAVPEIPPAEVSG 609
Cdd:COG3401   264 YRVYRSNSGDGPFTKVATV----TTTSYTDTGLTNG--TTYYYRVTAVD--AAGNESAPSNVVSvTTDLTPPAAPSGLTA 335

                         170       180       190       200       210       220       230       240
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 610 GGGSRSELVITWDPIPEELQNgegfGYVVAFRPFGTTTWiQTVVTSPDTPRYVfrNESILPFSPYEVKVGVYNNKG-EGP 688
Cdd:COG3401   336 TAVGSSSITLSWTASSDADVT----GYNVYRSTSGGGTY-TKIAETVTTTSYT--DTGLTPGTTYYYKVTAVDAAGnESA 408

                         250       260       270       280       290       300       310       320
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 689 FS---SITTVFSAEEEPTVAPSGVSVTSLSSSVIEVSWKAIPWKMSSGRLLGYEVRYWNNGGKEESSNRVKA-AGNETSI 764
Cdd:COG3401   409 PSeevSATTASAASGESLTASVDAVPLTDVAGATAAASAASNPGVSAAVLADGGDTGNAVPFTTTSSTVTATtTDTTTAN 488

                         330       340       350       360       370       380       390       400
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 765 RITGLKSNLAYYTAVRAYNSAGAGPFSATVNATTKKTPPSQPPGNVVWNVTDSRV-ILNWEEVRAMENESEVTGYKVLYR 843
Cdd:COG3401   489 LSVTTGSLVGGSGASSVTNSVSVIGASAAAAVGGAPDGTPNVTGASPVTVGASTGdVLITDLVSLTTSASSSVSGAGLGS 568

                         410
                  ....*....|....*..
gi 2024455041 844 TSGQNNMNVLNTDKTTA 860
Cdd:COG3401   569 GNLYLITTLGGSLLTTT 585

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: 67.65 E-value: 7.71e-14

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 319 IQVQIGSTVDFECKPKASPKARCSWKKGGEQLHENERITLLKDGGLRITNVTKVDAGSYTCVATNQFGTA 388
Cdd:cd20968     9 VTIIEGLKAVLPCTTMGNPKPSVSWIKGDDLIKENNRIAVLESGSLRIHNVQKEDAGQYRCVAKNSLGIA 78

Fibronectin type 3 domain [General function prediction only];

Pssm-ID: 442628 [Multi-domain] Cd Length: 603 Bit Score: 74.65 E-value: 1.41e-13

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 528 VTAYTIQARTPFSVGWQRVTTVPDVIDGNTFTTTVVDLNPWVEYEFRVVASNKIGGGEPSlPSEKVRTEEAVPEiPPAEV 607
Cdd:COG3401   162 SVAGAGVVVSPDTSATAAVATTSLTVTSTTLVDGGGDIEPGTTYYYRVAATDTGGESAPS-NEVSVTTPTTPPS-APTGL 239

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 608 SGGGGSRSELVITWDPIPEElqngEGFGYVVAFRPFGTTTWiqTVVTSPDTPRYVFRNesILPFSPYEVKVGVYNNKG-E 686
Cdd:COG3401   240 TATADTPGSVTLSWDPVTES----DATGYRVYRSNSGDGPF--TKVATVTTTSYTDTG--LTNGTTYYYRVTAVDAAGnE 311

                         170       180       190       200       210       220       230       240
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 687 GPFSSITTVFSAEEEPTvAPSGVSVTSLSSSVIEVSWKAipwkMSSGRLLGYEVRYWNNGGKeeSSNRVKAAGNETSIRI 766
Cdd:COG3401   312 SAPSNVVSVTTDLTPPA-APSGLTATAVGSSSITLSWTA----SSDADVTGYNVYRSTSGGG--TYTKIAETVTTTSYTD 384

                         250       260       270       280       290       300       310       320
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 767 TGLKSNLAYYTAVRAYNSAG-AGPFSATVNATTKKTPPSQPPGNVVWNVTDSRVILNWEEVRAMENESEVTGYkvlYRTS 845
Cdd:COG3401   385 TGLTPGTTYYYKVTAVDAAGnESAPSEEVSATTASAASGESLTASVDAVPLTDVAGATAAASAASNPGVSAAV---LADG 461

                         330       340       350       360
                  ....*....|....*....|....*....|....*....|.
gi 2024455041 846 GQNNMNVLNTDKTTAELLLPFNEDYIIEVKATTEGGDGTSS 886
Cdd:COG3401   462 GDTGNAVPFTTTSSTVTATTTDTTTANLSVTTGSLVGGSGA 502

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: 65.60 E-value: 4.47e-13

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041  225 KDTEIAVEDTLYWDCRASGKPKPSYRWLKNGEQ-LSVEGRIQIE----NGALTISSLNLTDSGRYQCIAENKHGVIYSSA 299
Cdd:smart00410   2 PSVTVKEGESVTLSCEASGSPPPEVTWYKQGGKlLAESGRFSVSrsgsTSTLTISNVTPEDSGTYTCAATNSSGSASSGT 81


                   ....
gi 2024455041  300 ELRV 303
Cdd:smart00410  82 TLTV 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: 64.56 E-value: 8.81e-13

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041  498 PGPPEHVRVDEITDTTAQISWQEGTDNH--SPVTAYTIQARTPFSvGWQRVTTVPdvidgNTFTTTVVDLNPWVEYEFRV 575
Cdd:smart00060   1 PSPPSNLRVTDVTSTSVTLSWEPPPDDGitGYIVGYRVEYREEGS-EWKEVNVTP-----SSTSYTLTGLKPGTEYEFRV 74


                   ....*....
gi 2024455041  576 VASNKIGGG 584
Cdd:smart00060  75 RAVNGAGEG 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: 64.96 E-value: 9.72e-13

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|...
gi 2024455041 238 DCRASGKPKPSYRWLKNGEQLSVEG--RIQIENGALTISSLN-LTDSGRYQCIAENKHGVIYS 297
Cdd:cd05848    25 NCEARGNPVPTYRWLRNGTEIDTESdyRYSLIDGNLIISNPSeVKDSGRYQCLATNSIGSILS 87

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: 64.19 E-value: 1.03e-12

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 2024455041 324 GSTVDFECKPKASPKARCSWKKGGEQLHENERITLLKDGGLRITNVTKVDAGSYTCVATNQFGTASGTTNLVV 396
Cdd:cd05745     2 GQTVDFLCEAQGYPQPVIAWTKGGSQLSVDRRHLVLSSGTLRISRVALHDQGQYECQAVNIVGSQRTVAQLTV 74

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: 64.44 E-value: 1.11e-12

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 2024455041 321 VQIGSTVDFECKPKASPKARCSWKKGGEQLH-ENERITLLKDGGLRITNVTKVDAGSYTCVATNQFGTASGTTNLVV 396
Cdd:cd20952    11 VAVGGTVVLNCQATGEPVPTISWLKDGVPLLgKDERITTLENGSLQIKGAEKSDTGEYTCVALNLSGEATWSAVLDV 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: 63.50 E-value: 1.35e-12

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|....*....
gi 2024455041 239 CRASGKPKPSYRWLKNGEQLS----VEGRIQIENGALTISSLNLTDSGRYQCIAENKHG 293
Cdd:cd00096     5 CSASGNPPPTITWYKNGKPLPpssrDSRRSELGNGTLTISNVTLEDSGTYTCVASNSAG 63

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: 64.10 E-value: 1.99e-12

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 2024455041 233 DTLYWDCRASGKPKPSYRWLKNGEQLSVEGRI-----QIENGALTISSLNLTDSGRYQCIAENKHGVIYSSAELRV 303
Cdd:cd05857    20 NTVKFRCPAAGNPTPTMRWLKNGKEFKQEHRIggykvRNQHWSLIMESVVPSDKGNYTCVVENEYGSINHTYHLDV 95

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: 63.57 E-value: 2.21e-12

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 320 QVQIGSTVDFECK-PKASPKARCSWKKGGEQLHE-NERITLLKDGGLRITNVTKVDAGSYTCVATNQFGT 387
Cdd:cd05724     8 QVAVGEMAVLECSpPRGHPEPTVSWRKDGQPLNLdNERVRIVDDGNLLIAEARKSDEGTYKCVATNMVGE 77

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: 63.02 E-value: 3.88e-12

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 134 PETLPAAKGSTVKLECFALGNPVPQINWRRTDGMPFPS----KIKLRKSNGMIEIPNFQQEDAGLYECITENSRGKNIAR 209
Cdd:cd05763     6 PHDITIRAGSTARLECAATGHPTPQIAWQKDGGTDFPAarerRMHVMPEDDVFFIVDVKIEDTGVYSCTAQNSAGSISAN 85


                  ....
gi 2024455041 210 GRLT 213
Cdd:cd05763    86 ATLT 89

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: 62.62 E-value: 4.39e-12

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 136 TLPAAKGSTVKLECFALGNPVPQINWRRTDGMPFPSKIKLRKSNGMIEIPNFQQEDAGLYECITENSRGKniARGrlTYY 215
Cdd:cd05876     4 SLVALRGQSLVLECIAEGLPTPTVKWLRPSGPLPPDRVKYQNHNKTLQLLNVGESDDGEYVCLAENSLGS--ARH--AYY 79

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: 62.27 E-value: 8.23e-12

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 218 PHWIQMIKDTEiAVEDTLY-WDCRASGKPKPSYRWLKNGEQLSVEG-RIQIE--NGALTISSLNLTDSGRYQCIAENKHG 293
Cdd:cd20976     2 PSFSSVPKDLE-AVEGQDFvAQCSARGKPVPRITWIRNAQPLQYAAdRSTCEagVGELHIQDVLPEDHGTYTCLAKNAAG 80

                          90
                  ....*....|
gi 2024455041 294 VIYSSAELRV 303
Cdd:cd20976    81 QVSCSAWVTV 90

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: 61.74 E-value: 8.68e-12

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 129 IEVQFPETLPAAKGSTVKLECFALGNPVPQINWRRtDGMPFPSK---IKLRKsNGMIEIPNFQQEDAGLYECITENSRGK 205
Cdd:cd20952     1 IILQGPQNQTVAVGGTVVLNCQATGEPVPTISWLK-DGVPLLGKderITTLE-NGSLQIKGAEKSDTGEYTCVALNLSGE 78


                  ....*...
gi 2024455041 206 NIARGRLT 213
Cdd:cd20952    79 ATWSAVLD 86

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: 61.19 E-value: 9.58e-12

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 2024455041 327 VDFECKPKASPKARCSWKKGGEQLHEN---ERITLLKDGGLRITNVTKVDAGSYTCVATNQFGTASGTT 392
Cdd:cd00096     1 VTLTCSASGNPPPTITWYKNGKPLPPSsrdSRRSELGNGTLTISNVTLEDSGTYTCVASNSAGGSASAS 69

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: 61.83 E-value: 9.76e-12

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 218 PHWIQMIKDTEIAVEDTLYWDCRASGKPKPSYRWLKNGEQLSVEGRIQIENG----ALTISSLNLTDSGRYQCIAENKHG 293
Cdd:cd20972     2 PQFIQKLRSQEVAEGSKVRLECRVTGNPTPVVRWFCEGKELQNSPDIQIHQEgdlhSLIIAEAFEEDTGRYSCLATNSVG 81

                          90
                  ....*....|
gi 2024455041 294 VIYSSAELRV 303
Cdd:cd20972    82 SDTTSAEIFV 91

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: 61.75 E-value: 1.06e-11

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041  134 PETLPAAKGSTVKLECFALGNPVPQINWRRTDGMP--FPSKIKLRKSNGM--IEIPNFQQEDAGLYECITENSRGKNIAR 209
Cdd:smart00410   1 PPSVTVKEGESVTLSCEASGSPPPEVTWYKQGGKLlaESGRFSVSRSGSTstLTISNVTPEDSGTYTCAATNSSGSASSG 80


                   ....
gi 2024455041  210 GRLT 213
Cdd:smart00410  81 TTLT 84

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: 61.74 E-value: 1.09e-11

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 226 DTEIAVEDTLYWDCRASGKPKPSYRWLKNGEQLSVEG-RI-QIENGALTISSLNLTDSGRYQCIAENKHGVIYSSAELRV 303
Cdd:cd20952     8 NQTVAVGGTVVLNCQATGEPVPTISWLKDGVPLLGKDeRItTLENGSLQIKGAEKSDTGEYTCVALNLSGEATWSAVLDV 87

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: 60.93 E-value: 2.21e-11

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 238 DCRASGKPKPSYRWLKNG---EQLSVEGRIQIENGALTISSLNLTDSGRYQCIAENKHGVIYSSAELRVV 304
Cdd:cd04978    20 ICEAEGNPQPTITWRLNGvpiEPAPEDMRRTVDGRTLIFSNLQPNDTAVYQCNASNVHGYLLANAFLHVL 89

Immunoglobulin domain; This family contains immunoglobulin-like domains.

Pssm-ID: 464046 [Multi-domain] Cd Length: 78 Bit Score: 60.27 E-value: 2.54e-11

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 2024455041 127 PKIEVQfPETLPAAKGSTVKLECFALGNPVPQINWRRTDGMPFP---SKIKLRKSNGMIEIPNFQQEDAGLYECITEN 201
Cdd:pfam13927   2 PVITVS-PSSVTVREGETVTLTCEATGSPPPTITWYKNGEPISSgstRSRSLSGSNSTLTISNVTRSDAGTYTCVASN 78

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: 60.49 E-value: 2.59e-11

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 134 PETLPAAKGSTVKLECFALGNPVPQINWRRTDG-MPFpSKIKLRKSNGMiEIPNFQQEDAGLYECITENSRGKNIARGRL 212
Cdd:cd05725     4 PQNQVVLVDDSAEFQCEVGGDPVPTVRWRKEDGeLPK-GRYEILDDHSL-KIRKVTAGDMGSYTCVAENMVGKIEASATL 81


                  .
gi 2024455041 213 T 213
Cdd:cd05725    82 T 82

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: 60.68 E-value: 2.80e-11

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 2024455041 233 DTLYWDCRASGKPKPSYRWLKNG---EQLSVEGRIQIENGALTISSLNLTDSGRYQCIAENKHGVIYSSAELRVV 304
Cdd:cd05867    15 ETARLDCQVEGIPTPNITWSINGapiEGTDPDPRRHVSSGALILTDVQPSDTAVYQCEARNRHGNLLANAHVHVV 89

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: 59.73 E-value: 4.43e-11

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 2024455041 139 AAKGSTVKLECFALGNPVPQINWRRTDGMPFPSKIKLRKSNGMIEIPNFQQEDAGLYECITENSRG 204
Cdd:cd05731     7 VLRGGVLLLECIAEGLPTPDIRWIKLGGELPKGRTKFENFNKTLKIENVSEADSGEYQCTASNTMG 72

Immunoglobulin domain; This family contains immunoglobulin-like domains.

Pssm-ID: 464046 [Multi-domain] Cd Length: 78 Bit Score: 59.50 E-value: 5.54e-11

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 2024455041 321 VQIGSTVDFECKPKASPKARCSWKKGGEQLHENERITLLKDGG---LRITNVTKVDAGSYTCVATN 383
Cdd:pfam13927  13 VREGETVTLTCEATGSPPPTITWYKNGEPISSGSTRSRSLSGSnstLTISNVTRSDAGTYTCVASN 78

Immunoglobulin domain; This family contains immunoglobulin-like domains.

Pssm-ID: 464046 [Multi-domain] Cd Length: 78 Bit Score: 59.12 E-value: 6.17e-11

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|....*.
gi 2024455041 239 CRASGKPKPSYRWLKNGEQL----SVEGRIQIENGALTISSLNLTDSGRYQCIAEN 290
Cdd:pfam13927  23 CEATGSPPPTITWYKNGEPIssgsTRSRSLSGSNSTLTISNVTRSDAGTYTCVASN 78

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: 58.73 E-value: 6.61e-11

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....
gi 2024455041 239 CRASGKPKPSYRWLKNGEQLSVEGRIQI-ENGALTISSLNLTDSGRYQCIAENKHGVIYSSAEL 301
Cdd:cd05746     5 CSAQGDPEPTITWNKDGVQVTESGKFHIsPEGYLAIRDVGVADQGRYECVARNTIGYASVSMVL 68

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: 58.95 E-value: 8.52e-11

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 2024455041 321 VQIGSTVDFECKPKASPKARCSWKKGGEQLHENeRITLLKDGGLRITNVTKVDAGSYTCVATNQFGTASGTTNLVV 396
Cdd:cd05725     9 VLVDDSAEFQCEVGGDPVPTVRWRKEDGELPKG-RYEILDDHSLKIRKVTAGDMGSYTCVAENMVGKIEASATLTV 83

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: 58.35 E-value: 1.62e-10

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 221 IQMIKDTEIAVEDTLYWDCRASGKPKPSYRWLKNGEQLSVEGRIQIE-----NGALTISSLNLTDSGRYQCIAENKHGVI 295
Cdd:cd20973     1 IQTLRDKEVVEGSAARFDCKVEGYPDPEVKWMKDDNPIVESRRFQIDqdedgLCSLIISDVCGDDSGKYTCKAVNSLGEA 80


                  ....*...
gi 2024455041 296 YSSAELRV 303
Cdd:cd20973    81 TCSAELTV 88

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: 57.93 E-value: 1.95e-10

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 2024455041 321 VQIGSTVDFECKPKASPKARCSWKKGGEQLHENERITLLKDGGLRITNVTKVDAGSYTCVATNQFGTASGTTNL 394
Cdd:cd20957    13 VDFGRTAVFNCSVTGNPIHTVLWMKDGKPLGHSSRVQILSEDVLVIPSVKREDKGMYQCFVRNDGDSAQATAEL 86

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: 58.24 E-value: 1.99e-10

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 319 IQVQIGSTVDFECKPKASPKARCSWKKGGEQLHEN-ERITLLKDGGLRIT----NVTKVDAGSYTCVATNQFGTASGTTN 393
Cdd:cd05892    10 KKVLEGDPVRLECQISAIPPPQIFWKKNNEMLQYNtDRISLYQDNCGRIClliqNANKKDAGWYTVSAVNEAGVVSCNAR 89


                  ...
gi 2024455041 394 LVV 396
Cdd:cd05892    90 LDV 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: 58.00 E-value: 2.19e-10

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 131 VQFPETLPAAKGSTVKLECFALGNPVPQINWRRtDGMPFPSKIKLRKSNGMIEIPNFQQEDAGLYECITENSRGKNIARG 210
Cdd:cd05728     3 LKVISDTEADIGSSLRWECKASGNPRPAYRWLK-NGQPLASENRIEVEAGDLRITKLSLSDSGMYQCVAENKHGTIYASA 81


                  ...
gi 2024455041 211 RLT 213
Cdd:cd05728    82 ELA 84

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: 57.86 E-value: 2.59e-10

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 2024455041 239 CRASGKPKPSYRWLKNGEQLSVEGRIQI-ENGALTISSLNLTDSGRYQCIAENKHGVIYSSAELRV 303
Cdd:cd04969    24 CKPKASPKPTISWSKGTELLTNSSRICIlPDGSLKIKNVTKSDEGKYTCFAVNFFGKANSTGSLSV 89

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: 57.52 E-value: 3.30e-10

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041  406 PSNMDVTVGESVILPCQVQHDPilDISFTWYFNGTLTDFKKDASHFEKVGGSASgdLMIRNIQLKHSGKYVCMVKTEVDS 485
Cdd:smart00410   1 PPSVTVKEGESVTLSCEASGSP--PPEVTWYKQGGKLLAESGRFSVSRSGSTST--LTISNVTPEDSGTYTCAATNSSGS 76


                   ....*....
gi 2024455041  486 VASAADLIV 494
Cdd:smart00410  77 ASSGTTLTV 85

Immunoglobulin domain; This family contains immunoglobulin-like domains.

Pssm-ID: 464046 [Multi-domain] Cd Length: 78 Bit Score: 56.80 E-value: 3.76e-10

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 401 RIILAPSNMDVTVGESVILPCQVQHDPilDISFTWYFNGTLTdfkKDASHFEKVGGSASGDLMIRNIQLKHSGKYVCMVK 480
Cdd:pfam13927   3 VITVSPSSVTVREGETVTLTCEATGSP--PPTITWYKNGEPI---SSGSTRSRSLSGSNSTLTISNVTRSDAGTYTCVAS 77

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: 57.02 E-value: 4.10e-10

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 225 KDTEIAVEDTLYWDCRASGKPKPSYRWLKNGEQLSVeGRIQI-ENGALTISSLNLTDSGRYQCIAENKHGVIYSSAELRV 303
Cdd:cd05725     5 QNQVVLVDDSAEFQCEVGGDPVPTVRWRKEDGELPK-GRYEIlDDHSLKIRKVTAGDMGSYTCVAENMVGKIEASATLTV 83

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: 56.49 E-value: 5.42e-10

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|.
gi 2024455041 234 TLYWDCRASGKPKPSYRWLKNGEQLSVEGRIQI-ENGALTISSLNLTDSGRYQCIAENKHGVIYSSAELRV 303
Cdd:cd05745     4 TVDFLCEAQGYPQPVIAWTKGGSQLSVDRRHLVlSSGTLRISRVALHDQGQYECQAVNIVGSQRTVAQLTV 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: 56.84 E-value: 6.67e-10

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 218 PHWIQMIKDTE----IAVEDTLYWDCRASGKPKPSYRWLKNGEQLSVEGRIQI-----ENGALTISSLNLTDSGRYQCIA 288
Cdd:cd05729     1 PRFTDTEKMEErehaLPAANKVRLECGAGGNPMPNITWLKDGKEFKKEHRIGGtkveeKGWSLIIERAIPRDKGKYTCIV 80

                          90
                  ....*....|....*
gi 2024455041 289 ENKHGVIYSSAELRV 303
Cdd:cd05729    81 ENEYGSINHTYDVDV 95

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: 56.35 E-value: 7.90e-10

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 603 PPAEVSGGGGSRSELVITWDPIPEElqNGEGFGYVVAFRPFGTTTWIQTVVTSPDTPRYVFRNesILPFSPYEVKVGVYN 682
Cdd:cd00063     3 PPTNLRVTDVTSTSVTLSWTPPEDD--GGPITGYVVEYREKGSGDWKEVEVTPGSETSYTLTG--LKPGTEYEFRVRAVN 78

                          90
                  ....*....|...
gi 2024455041 683 NKGEGPFSSITTV 695
Cdd:cd00063    79 GGGESPPSESVTV 91

Immunoglobulin I-set domain;

Pssm-ID: 400151 [Multi-domain] Cd Length: 90 Bit Score: 56.50 E-value: 8.44e-10

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 401 RIILAPSNMDVTVGESVILPCQVQHDPilDISFTWYFNGtlTDFKKDASH-FEKVGGSASgdLMIRNIQLKHSGKYVCMV 479
Cdd:pfam07679   2 KFTQKPKDVEVQEGESARFTCTVTGTP--DPEVSWFKDG--QPLRSSDRFkVTYEGGTYT--LTISNVQPDDSGKYTCVA 75

                          90
                  ....*....|....*
gi 2024455041 480 KTEVDSVASAADLIV 494
Cdd:pfam07679  76 TNSAGEAEASAELTV 90

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: 55.64 E-value: 1.46e-09

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 127 PKIEVQFPE-TLpaAKGSTVKLECFALGNPVPQINWRRtDGMPFPSKIKLRKS---------NGMIEIPNFQQEDAGLYE 196
Cdd:cd20956     2 PVLLETFSEqTL--QPGPSVSLKCVASGNPLPQITWTL-DGFPIPESPRFRVGdyvtsdgdvVSYVNISSVRVEDGGEYT 78


                  ....*....
gi 2024455041 197 CITENSRGK 205
Cdd:cd20956    79 CTATNDVGS 87

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: 55.21 E-value: 2.04e-09

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 134 PETLPAAKGSTVKLECFALGNPVPQINWRRTDGMP--FPSKIKLRKSNGMIEIPNFQQEDAGLYECITEN 201
Cdd:cd20970     9 SFTVTAREGENATFMCRAEGSPEPEISWTRNGNLIieFNTRYIVRENGTTLTIRNIRRSDMGIYLCIASN 78

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: 55.21 E-value: 2.58e-09

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 2024455041 224 IKDTEIAVEDTLYWDCRASGK-PKPSYRWLKNGEQL--SVEGRIQIENGA----LTISSLNLTDSGRYQCIAENKHG 293
Cdd:cd05750     6 MKSQTVQEGSKLVLKCEATSEnPSPRYRWFKDGKELnrKRPKNIKIRNKKknseLQINKAKLEDSGEYTCVVENILG 82

Immunoglobulin I-set domain;

Pssm-ID: 400151 [Multi-domain] Cd Length: 90 Bit Score: 54.96 E-value: 2.94e-09

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 127 PKIeVQFPETLPAAKGSTVKLECFALGNPVPQINWRRtDGMPFPS--KIKLRKSNGM--IEIPNFQQEDAGLYECITENS 202
Cdd:pfam07679   1 PKF-TQKPKDVEVQEGESARFTCTVTGTPDPEVSWFK-DGQPLRSsdRFKVTYEGGTytLTISNVQPDDSGKYTCVATNS 78

                          90
                  ....*....|.
gi 2024455041 203 RGKNIARGRLT 213
Cdd:pfam07679  79 AGEAEASAELT 89

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: 54.94 E-value: 3.40e-09

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 2024455041 228 EIAVEDTLYWDCRASGKPKPSYRWLKNGEQLSVEG--RIQIENGALTISS-LNLTDSGRYQCIAENKHGVIYSS-AELR 302
Cdd:cd04967    15 EDSDEKKVALNCRARANPVPSYRWLMNGTEIDLESdyRYSLVDGTLVISNpSKAKDAGHYQCLATNTVGSVLSReATLQ 93

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: 54.50 E-value: 3.71e-09

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|....*.
gi 2024455041 343 WKKGGEQLHENERITLLKDGGLRITNVTK-VDAGSYTCVATNQFG-TASGTTNLVV 396
Cdd:cd20958    34 WEKDGRRLPLNHRQRVFPNGTLVIENVQRsSDEGEYTCTARNQQGqSASRSVFVKV 89

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: 54.12 E-value: 4.29e-09

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 2024455041 237 WDCRASGKPKPSYRWLKNGEQLSVEGRIQI-ENGALTISSLNLTDSGRYQCIAENKHGVIYSSAEL 301
Cdd:cd05723    17 FECEVTGKPTPTVKWVKNGDVVIPSDYFKIvKEHNLQVLGLVKSDEGFYQCIAENDVGNAQASAQL 82

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: 53.86 E-value: 7.29e-09

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 239 CRASGKPKPSYRWLKNG---EQLSVEGRI-QIENGALTISSLNLTDSGRYQCIAENKHGVIYSS-AELRV 303
Cdd:cd05738    21 CAASGNPDPEISWFKDFlpvDTATSNGRIkQLRSGALQIENSEESDQGKYECVATNSAGTRYSApANLYV 90

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: 53.65 E-value: 7.44e-09

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 719 IEVSWKaiPWKMSSGRLLGYEVRYWNNGGKEESSNRVKAaGNETSIRITGLKSNLAYYTAVRAYNSAGAGPFSATVNATT 798
Cdd:cd00063    17 VTLSWT--PPEDDGGPITGYVVEYREKGSGDWKEVEVTP-GSETSYTLTGLKPGTEYEFRVRAVNGGGESPPSESVTVTT 93

Immunoglobulin domain; This domain contains immunoglobulin-like domains.

Pssm-ID: 464026 [Multi-domain] Cd Length: 79 Bit Score: 52.40 E-value: 1.45e-08

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 227 TEIAVEDTLYWD-------CRASGKPKPSYRWLKNGEQLSvegriqiENGALTISSLNLTDSGRYQCIAENKHGVIYS-S 298
Cdd:pfam13895   2 PVLTPSPTVVTEgepvtltCSAPGNPPPSYTWYKDGSAIS-------SSPNFFTLSVSAEDSGTYTCVARNGRGGKVSnP 74


                  ....*
gi 2024455041 299 AELRV 303
Cdd:pfam13895  75 VELTV 79

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: 1.88e-08

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 316 KKMIQVQIGSTVDFECKPKASPKARCSWKKGGEQLHENERItllkdGGLRITN---------VTKVDAGSYTCVATNQFG 386
Cdd:cd05857    11 KKLHAVPAANTVKFRCPAAGNPTPTMRWLKNGKEFKQEHRI-----GGYKVRNqhwslimesVVPSDKGNYTCVVENEYG 85

                          90
                  ....*....|
gi 2024455041 387 TASGTTNLVV 396
Cdd:cd05857    86 SINHTYHLDV 95

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: 52.24 E-value: 2.04e-08

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 239 CRASGKPKPSYRWLKNGEQLSVEGRIQI-ENGALTISSLNLTDSGRYQCIAENKHGVIYS 297
Cdd:cd20968    21 CTTMGNPKPSVSWIKGDDLIKENNRIAVlESGSLRIHNVQKEDAGQYRCVAKNSLGIAYS 80

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: 52.17 E-value: 2.55e-08

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 2024455041 239 CRASGKPKPSYRWLKNGEQLSV--EGRIQIENGALTISSLNLTDSGRYQCIAENKHGVIYSSAELRV 303
Cdd:cd05856    26 CVASGNPRPDITWLKDNKPLTPpeIGENKKKKWTLSLKNLKPEDSGKYTCHVSNRAGEINATYKVDV 92

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: 51.56 E-value: 2.63e-08

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 2024455041 145 VKLECFALGNPVPQINWRRtDGMPFPSKIKLRK----SNGMIEIPNFQQEDAGLYECITENSRGKNIAR 209
Cdd:cd00096     1 VTLTCSASGNPPPTITWYK-NGKPLPPSSRDSRrselGNGTLTISNVTLEDSGTYTCVASNSAGGSASA 68

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: 51.78 E-value: 4.34e-08

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 218 PHWIQMIKDTEIAVEDTLYWDCRASGKPKPSYRWLKNGEQLSVEG------RIQIENGALTISSL-----NLTDSGRYQC 286
Cdd:cd07693     1 PRIVEHPSDLIVSKGDPATLNCKAEGRPTPTIQWLKNGQPLETDKddprshRIVLPSGSLFFLRVvhgrkGRSDEGVYVC 80

                          90
                  ....*....|....*...
gi 2024455041 287 IAENKHGVIYS-SAELRV 303
Cdd:cd07693    81 VAHNSLGEAVSrNASLEV 98

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: 50.79 E-value: 5.08e-08

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 2024455041 417 VILPCQVQHDPILDIsfTWYFNGTLTDFKKDASHFEKVGgsaSGDLMIRNIQLKHSGKYVCMVKTEVDSVASA 489
Cdd:cd00096     1 VTLTCSASGNPPPTI--TWYKNGKPLPPSSRDSRRSELG---NGTLTISNVTLEDSGTYTCVASNSAGGSASA 68

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: 5.51e-08

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 2024455041 239 CRASGKPKPSYRWLKNGEQLSVEGRIQI-ENGALTISSLNLTDSGRYQCIAENKHGVIYSSAELRV 303
Cdd:cd20957    23 CSVTGNPIHTVLWMKDGKPLGHSSRVQIlSEDVLVIPSVKREDKGMYQCFVRNDGDSAQATAELKL 88

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: 51.27 E-value: 5.83e-08

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 2024455041 239 CRASGKPKPSYRWLKNGEQLSVEGRI---QIEN----GALTISSLNLTDSGRYQCIAENKHGVIYSSAELRV 303
Cdd:cd20951    22 VEVQGKPDPEVKWYKNGVPIDPSSIPgkyKIESeygvHVLHIRRVTVEDSAVYSAVAKNIHGEASSSASVVV 93

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: 6.02e-08

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 239 CRASGKPKPSYRWLKNGEQLSVEGRIQ---IENGA-LTISSLNLTDSGRYQCIAENKHGV 294
Cdd:cd05736    22 CHAEGIPLPRVQWLKNGMDINPKLSKQltlIANGSeLHISNVRYEDTGAYTCIAKNEGGV 81

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: 51.32 E-value: 6.05e-08

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 2024455041 238 DCRASGKPKPSYRWLKNGEQL---SVEGRIQIENGALTISSL-----NLTDSGRYQCIAENKH-GVIYS-SAELRV 303
Cdd:cd05722    22 NCSAESDPPPKIEWKKDGVLLnlvSDERRQQLPNGSLLITSVvhskhNKPDEGFYQCVAQNESlGSIVSrTARVTV 97

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: 51.02 E-value: 7.94e-08

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 2024455041 239 CRASGKPKPSYRWLKNGEQLSVEGRIQIE----NGALTISSLNLT-----DSGRYQCIAENKHGVIYSSAELRV 303
Cdd:cd20956    23 CVASGNPLPQITWTLDGFPIPESPRFRVGdyvtSDGDVVSYVNISsvrveDGGEYTCTATNDVGSVSHSARINV 96

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: 50.69 E-value: 7.97e-08

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041  803 PSQPPGNVVWNVTDSRVILNWEEVRAMENESEVTGYKVLYRTSGQNNMNVLNTDKTTAELL--LPFNEDYIIEVKATTEG 880
Cdd:smart00060   1 PSPPSNLRVTDVTSTSVTLSWEPPPDDGITGYIVGYRVEYREEGSEWKEVNVTPSSTSYTLtgLKPGTEYEFRVRAVNGA 80


                   ...
gi 2024455041  881 GDG 883
Cdd:smart00060  81 GEG 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: 50.48 E-value: 8.11e-08

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 225 KDTEIAVEDTLYWDCRAS-GKPKPSYRWLKNGEQLSVEG-RIQI-ENGALTISSLNLTDSGRYQCIAENKHGVIYSS-AE 300
Cdd:cd05724     5 SDTQVAVGEMAVLECSPPrGHPEPTVSWRKDGQPLNLDNeRVRIvDDGNLLIAEARKSDEGTYKCVATNMVGERESRaAR 84


                  ...
gi 2024455041 301 LRV 303
Cdd:cd05724    85 LSV 87

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: 50.68 E-value: 8.32e-08

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 315 MKKMIQVQIGSTVDFECKPKASPKARCSWKKGGEQL--HENERITLLKDGG--LRITNVTKVDAGSYTCVATNQFGTASG 390
Cdd:cd05729    10 EEREHALPAANKVRLECGAGGNPMPNITWLKDGKEFkkEHRIGGTKVEEKGwsLIIERAIPRDKGKYTCIVENEYGSINH 89


                  ....*.
gi 2024455041 391 TTNLVV 396
Cdd:cd05729    90 TYDVDV 95

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: 50.77 E-value: 8.66e-08

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 2024455041 238 DCRASGKPKPSYRWLKNGEQLSVEGRIQI-ENGALTISSLNLTDSGRYQCIAENKHGVIYSSAELRV 303
Cdd:cd05852    23 ECKPKAAPKPKFSWSKGTELLVNNSRISIwDDGSLEILNITKLDEGSYTCFAENNRGKANSTGVLSV 89

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: 9.09e-08

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 320 QVQIGSTVDFECKPKASPKARCSWKKGGEQLHE-NERITLLKDGG-LRITNVTKVDAGSYTCVATNQ-FGTASGTTNLVV 396
Cdd:cd20970    13 TAREGENATFMCRAEGSPEPEISWTRNGNLIIEfNTRYIVRENGTtLTIRNIRRSDMGIYLCIASNGvPGSVEKRITLQV 92

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: 50.48 E-value: 9.78e-08

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 222 QMIKDTEIAVEDTLYWDCRASGKPKPSYRWLKNGEQLSVEGRIQI----ENGALTISSLN--LTD-SGRYQCIAENKHGV 294
Cdd:cd05733     6 QSPKDYIVDPRDNITIKCEAKGNPQPTFRWTKDGKFFDPAKDPRVsmrrRSGTLVIDNHNggPEDyQGEYQCYASNELGT 85

                          90
                  ....*....|
gi 2024455041 295 IYSSaELRVV 304
Cdd:cd05733    86 AISN-EIRLV 94

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: 50.72 E-value: 9.79e-08

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 321 VQIGSTVDFECKPKASPKARCSWKKGGEQ--------LHENERITLLKDGGLRITNVTKVDAGSYTCVATNQFGTASGTT 392
Cdd:cd05726    11 VALGRTVTFQCETKGNPQPAIFWQKEGSQnllfpyqpPQPSSRFSVSPTGDLTITNVQRSDVGYYICQALNVAGSILAKA 90


                  ....*.
gi 2024455041 393 NLVVTE 398
Cdd:cd05726    91 QLEVTD 96

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: 50.70 E-value: 1.04e-07

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 2024455041 323 IGSTVDFECKPKASPKARCSWKKGGEQLH-ENERITLLKDGG-LRITNVTKVDAGSYTCVATNQFGTASGTTNLVV 396
Cdd:cd05730    17 LGQSVTLACDADGFPEPTMTWTKDGEPIEsGEEKYSFNEDGSeMTILDVDKLDEAEYTCIAENKAGEQEAEIHLKV 92

Immunoglobulin (Ig)-like domain of class III semaphorin Sema3; The members here are composed of the immunoglobulin (Ig)-like domain of Sema3 and similar proteins. Semaphorins are classified based on structural features additional to the Sema domain. Sema3 is a Class III semaphorin that is secreted. It is a vertebrate class having a Sema domain, an Ig domain, a short basic domain. They have been shown to be axonal guidance cues and have a part in the regulation of the cardiovascular, immune, and respiratory systems. Sema3A, the prototype member of this class III subfamily, induces growth cone collapse and is an inhibitor of axonal sprouting. In perinatal rat cortex, it acts as a chemoattractant and functions to direct the orientated extension of apical dendrites. It may play a role, prior to the development of apical dendrites, in signaling the radial migration of newborn cortical neurons towards the upper layers. Sema3A selectively inhibits vascular endothelial growth factor receptor (VEGF)-induced angiogenesis and induces microvascular permeability. This group also includes Sema3B, -C, -D, -E, -G.

Pssm-ID: 409455 Cd Length: 92 Bit Score: 50.42 E-value: 1.05e-07

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 313 NPMKKMIQVQIGSTVDFECKPKaSPKARCSW--KKGGEQLHE----NERItLLKDGGLRITNVTKVDAGSYTCVAT-NQF 385
Cdd:cd05871     1 NAEEKVVYGVEGNSTFLECLPK-SPQATVKWlfQRGGDQRKEevksEERL-IVTDRGLLLRSLQRSDAGVYTCQAVeHGF 78

                          90
                  ....*....|....
gi 2024455041 386 GTASGTTNLVVTEP 399
Cdd:cd05871    79 SQTLVKIRLHVIEP 92

Fibronectin type III domain;

Pssm-ID: 394996 [Multi-domain] Cd Length: 85 Bit Score: 50.11 E-value: 1.07e-07

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 2024455041 719 IEVSWKAIPwkMSSGRLLGYEVRYWNnGGKEESSNRVKAAGNETSIRITGLKSNLAYYTAVRAYNSAGAGPFS 791
Cdd:pfam00041  16 LTVSWTPPP--DGNGPITGYEVEYRP-KNSGEPWNEITVPGTTTSVTLTGLKPGTEYEVRVQAVNGGGEGPPS 85

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: 50.27 E-value: 1.16e-07

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 2024455041 324 GSTVDFECKPKASPKARCSWKKGGEQLHENERITLLKDG----GLRITNVTKVDAGSYTCVATNQFGTASGTTNLVV 396
Cdd:cd20973    12 GSAARFDCKVEGYPDPEVKWMKDDNPIVESRRFQIDQDEdglcSLIISDVCGDDSGKYTCKAVNSLGEATCSAELTV 88

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: 50.31 E-value: 1.22e-07

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 2024455041 228 EIAVEDTLYWDCRASGKPKPSYRWLKNGEQLSVE--GRIQIENGALTISS-LNLTDSGRYQCIAENKHGVIYS-SAELR 302
Cdd:cd05850    16 EGSAEEKVTLACRARASPPATYRWKMNGTELKMEpdSRYRLVAGNLVISNpVKAKDAGSYQCLASNRRGTVVSrEASLR 94

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: 50.10 E-value: 1.26e-07

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....
gi 2024455041 233 DTLYWDCRASGKPKPSYRWLK-NGEQLSveGRIQIEN--GALTISSLNLTDSGRYQCIAENKHG 293
Cdd:cd05731    11 GVLLLECIAEGLPTPDIRWIKlGGELPK--GRTKFENfnKTLKIENVSEADSGEYQCTASNTMG 72

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: 50.27 E-value: 1.32e-07

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 307 APDFSKNPMKKmiQVQIGSTVDFECKPKASPKARCSWKKGGEQLHENERITLLKDGGLR---ITNVTKVDAGSYTCVATN 383
Cdd:cd20972     1 PPQFIQKLRSQ--EVAEGSKVRLECRVTGNPTPVVRWFCEGKELQNSPDIQIHQEGDLHsliIAEAFEEDTGRYSCLATN 78

                          90
                  ....*....|...
gi 2024455041 384 QFGTASGTTNLVV 396
Cdd:cd20972    79 SVGSDTTSAEIFV 91

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: 49.87 E-value: 1.57e-07

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 2024455041 222 QMIKDTEIAvEDTLYWDCRASGKPKPSYRWLKNGEQLSVEGRIQI-ENGALTISSLNL-TDSGRYQCIAENKHG 293
Cdd:cd20958     6 PMGNLTAVA-GQTLRLHCPVAGYPISSITWEKDGRRLPLNHRQRVfPNGTLVIENVQRsSDEGEYTCTARNQQG 78

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: 49.55 E-value: 1.97e-07

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 134 PETLPAAKGSTVKLECFALGNPVPQINWRRTDG-MPFPSKIKLRKSnGMIEIPNFQQEDAGLYECITENSRGkniargrl 212
Cdd:cd20968     6 PTNVTIIEGLKAVLPCTTMGNPKPSVSWIKGDDlIKENNRIAVLES-GSLRIHNVQKEDAGQYRCVAKNSLG-------- 76


                  ....*.
gi 2024455041 213 TYYAKP 218
Cdd:cd20968    77 IAYSKP 82

Fibronectin type III domain;

Pssm-ID: 394996 [Multi-domain] Cd Length: 85 Bit Score: 49.34 E-value: 2.28e-07

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 603 PPAEVSGGGGSRSELVITWDPIPEelQNGEGFGYVVAFRPFGTTTWIQTVVTSPDTPRYVFRNesILPFSPYEVKVGVYN 682
Cdd:pfam00041   2 APSNLTVTDVTSTSLTVSWTPPPD--GNGPITGYEVEYRPKNSGEPWNEITVPGTTTSVTLTG--LKPGTEYEVRVQAVN 77


                  ....*...
gi 2024455041 683 NKGEGPFS 690
Cdd:pfam00041  78 GGGEGPPS 85

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: 49.09 E-value: 2.34e-07

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 128 KIEVQFPETLPAAKGSTVKLECFALG-NPVPQINWRRTDGmPFPSKIklRKSNGMIEIPNFQQEDAGLYECITENSRgkN 206
Cdd:cd05754     2 QVTVEEPRSQEVRPGADVSFICRAKSkSPAYTLVWTRVNG-TLPSRA--MDFNGILTIRNVQLSDAGTYVCTGSNML--D 76


                  ....*....
gi 2024455041 207 IARGRLTYY 215
Cdd:cd05754    77 TDEATATLY 85

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: 49.28 E-value: 2.52e-07

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 134 PETLPAAKGSTVKLECFALGNPVPQINWRRtDGMPFPS----KIKLRKSNGMIEIPNFQQEDAGLYECITENSRGKNIAR 209
Cdd:cd05747    10 PRSLTVSEGESARFSCDVDGEPAPTVTWMR-EGQIIVSsqrhQITSTEYKSTFEISKVQMSDEGNYTVVVENSEGKQEAQ 88


                  ....
gi 2024455041 210 GRLT 213
Cdd:cd05747    89 FTLT 92

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: 49.16 E-value: 3.15e-07

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 310 FSKNPMKkmIQVQIGSTVDFECKPKASPKARCSWKK-GGEQL--HENERITLL-KDGGLRITNVTKVDAGSYTCVATNQF 385
Cdd:cd05763     2 FTKTPHD--ITIRAGSTARLECAATGHPTPQIAWQKdGGTDFpaARERRMHVMpEDDVFFIVDVKIEDTGVYSCTAQNSA 79

                          90
                  ....*....|.
gi 2024455041 386 GTASGTTNLVV 396
Cdd:cd05763    80 GSISANATLTV 90

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: 49.03 E-value: 3.47e-07

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 806 PPGNV-VWNVTDSRVILNWEEVRamENESEVTGYKVLYRTSGQNNMNVLNT---DKTTAEL--LLPFNEdYIIEVKATTE 879
Cdd:cd00063     3 PPTNLrVTDVTSTSVTLSWTPPE--DDGGPITGYVVEYREKGSGDWKEVEVtpgSETSYTLtgLKPGTE-YEFRVRAVNG 79

                          90
                  ....*....|
gi 2024455041 880 GGDGTSSDQI 889
Cdd:cd00063    80 GGESPPSESV 89

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: 49.06 E-value: 3.75e-07

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 216 AKPHWIQMikDTEIAVE-DTLYWDCRASGKPKPSYRWLK-----NGEQLSVEGRI----QIENGALTISSLNLTDSGRYQ 285
Cdd:cd05732     1 VQPKITYL--ENQTAVElEQITLTCEAEGDPIPEITWRRatrgiSFEEGDLDGRIvvrgHARVSSLTLKDVQLTDAGRYD 78

                          90
                  ....*....|....*...
gi 2024455041 286 CIAENKHGVIYSSAELRV 303
Cdd:cd05732    79 CEASNRIGGDQQSMYLEV 96

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: 48.95 E-value: 4.27e-07

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 126 EPKIEVQFPETLPAakgstvKLECFALGNPVPQINWRRTDGMPFPSKIKLRK--SNGMIEIPNFQQED------AGLYEC 197
Cdd:cd20955     7 EPTNRIDFSNSTGA------EIECKASGNPMPEIIWIRSDGTAVGDVPGLRQisSDGKLVFPPFRAEDyrqevhAQVYAC 80

                          90
                  ....*....|..
gi 2024455041 198 ITENSRGKNIAR 209
Cdd:cd20955    81 LARNQFGSIISR 92

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: 48.17 E-value: 5.09e-07

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 134 PETLPAAKGSTVKLECFA-LGNPVPQINWRRtDGMPFPSKIKLRK--SNGMIEIPNFQQEDAGLYECITENSRGKNIAR- 209
Cdd:cd05724     4 PSDTQVAVGEMAVLECSPpRGHPEPTVSWRK-DGQPLNLDNERVRivDDGNLLIAEARKSDEGTYKCVATNMVGERESRa 82


                  ....
gi 2024455041 210 GRLT 213
Cdd:cd05724    83 ARLS 86

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: 48.44 E-value: 5.13e-07

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 2024455041 239 CRASGKPKPSYRWLKNGEQLSV---EGRIQIENGALTISSLNLTDSGRYQCIAENKHGVIYSSAELRVV 304
Cdd:cd05868    21 CRANGNPKPSISWLTNGVPIEIaptDPSRKVDGDTIIFSKVQERSSAVYQCNASNEYGYLLANAFVNVL 89

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: 48.40 E-value: 5.36e-07

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 133 FPETLPAAKGSTVKLECFALGNPVPQINWRRtDGMPF---PSKIKLRKSNGMIEIPNFQQEDAGLYECITENSRGKNIAR 209
Cdd:cd20976     7 VPKDLEAVEGQDFVAQCSARGKPVPRITWIR-NAQPLqyaADRSTCEAGVGELHIQDVLPEDHGTYTCLAKNAAGQVSCS 85


                  ....
gi 2024455041 210 GRLT 213
Cdd:cd20976    86 AWVT 89

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: 48.17 E-value: 6.06e-07

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 2024455041 324 GSTVDFECKPKASPKARCSW-KKGGEQLheNERITLLKDG-GLRITNVTKVDAGSYTCVATNQFGTASGTTNLVV 396
Cdd:cd05731    10 GGVLLLECIAEGLPTPDIRWiKLGGELP--KGRTKFENFNkTLKIENVSEADSGEYQCTASNTMGSARHTISVTV 82

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: 6.92e-07

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|....*.
gi 2024455041 239 CRASGKPKPSYRWLKNGEQL--SVEGRIQIENGA-LTISSLNLTDSGRYQCIAENK 291
Cdd:cd20970    24 CRAEGSPEPEISWTRNGNLIieFNTRYIVRENGTtLTIRNIRRSDMGIYLCIASNG 79

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: 48.03 E-value: 6.97e-07

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 322 QIGSTVDFECKPKASPKARCSWKKGGEQLHEN--ERITLLKDGG-LRITNVTKVDAGSYTCVATNQFGTASGTTNLVVTE 398
Cdd:cd05736    13 EPGVEASLRCHAEGIPLPRVQWLKNGMDINPKlsKQLTLIANGSeLHISNVRYEDTGAYTCIAKNEGGVDEDISSLFVED 92

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: 48.03 E-value: 7.54e-07

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 127 PKIEVqFPETLPAAKGSTVKLECFALGNPVPQINWRRTD---GMPFPSKIKLRKSNGMIEIPNFQQEDAGLYECITENSR 203
Cdd:cd05736     1 PVIRV-YPEFQAKEPGVEASLRCHAEGIPLPRVQWLKNGmdiNPKLSKQLTLIANGSELHISNVRYEDTGAYTCIAKNEG 79


                  .
gi 2024455041 204 G 204
Cdd:cd05736    80 G 80

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: 47.94 E-value: 7.80e-07

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 316 KKMIQVQIGSTVDFECKPKA-SPKARCSWKKGGEQLHENERITllkDGGLRITNVTKVDAGSYTCVATNQFGTASGTTNL 394
Cdd:cd05754     8 PRSQEVRPGADVSFICRAKSkSPAYTLVWTRVNGTLPSRAMDF---NGILTIRNVQLSDAGTYVCTGSNMLDTDEATATL 84

Immunoglobulin domain; This family contains immunoglobulin-like domains.

Pssm-ID: 464046 [Multi-domain] Cd Length: 78 Bit Score: 47.56 E-value: 8.43e-07

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 2024455041  30 STVSVREGQGVVLLC---GTPPrageLSFAWIFNEYPSFVQEDSRRFVSQETGHLYIAKVEPSDVGNYTCVVT 99
Cdd:pfam13927   9 SSVTVREGETVTLTCeatGSPP----PTITWYKNGEPISSGSTRSRSLSGSNSTLTISNVTRSDAGTYTCVAS 77

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: 8.49e-07

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 327 VDFECKPKASPKARCSWKKGGEQLHENERITLLKDGGLRITNVTKVDAGSYTCVATNQFGTASGTTNLVV 396
Cdd:cd05723    15 IVFECEVTGKPTPTVKWVKNGDVVIPSDYFKIVKEHNLQVLGLVKSDEGFYQCIAENDVGNAQASAQLII 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: 48.05 E-value: 8.84e-07

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 216 AKPHWIQMIKDTEIAVEDTLYWDCRASGKPKPSYRWLK-----NGEQLSVEGRIQIEN----GALTISSLNLTDSGRYQC 286
Cdd:cd05869     1 AKPKITYVENQTAMELEEQITLTCEASGDPIPSITWRTstrniSSEEKTLDGHIVVRSharvSSLTLKYIQYTDAGEYLC 80

                          90
                  ....*....|....*..
gi 2024455041 287 IAENKHGVIYSSAELRV 303
Cdd:cd05869    81 TASNTIGQDSQSMYLEV 97

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: 47.18 E-value: 9.56e-07

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|...
gi 2024455041 327 VDFECKPKASPKARCSWKKGGEQLHENERITLLKDGGLRITNVTKVDAGSYTCVATNQFGTAS 389
Cdd:cd05746     1 VQIPCSAQGDPEPTITWNKDGVQVTESGKFHISPEGYLAIRDVGVADQGRYECVARNTIGYAS 63

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: 47.39 E-value: 1.00e-06

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 127 PKIeVQFPETLPAAK-GSTVKLECFALGNPVPQINW----RRTDGMPFPSKIKlrksNGMIEIPNFQQEDAGLYECITEN 201
Cdd:cd20978     1 PKF-IQKPEKNVVVKgGQDVTLPCQVTGVPQPKITWlhngKPLQGPMERATVE----DGTLTIINVQPEDTGYYGCVATN 75


                  ....
gi 2024455041 202 SRGK 205
Cdd:cd20978    76 EIGD 79

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: 47.49 E-value: 1.05e-06

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 131 VQFPETLPAAKGSTVKLECFALGNPVPQINWRRTDGM-PFPSKIKLRKSNG---MIEIPNFQQEDAGLYECITENSRGKN 206
Cdd:cd05744     4 LQAPGDLEVQEGRLCRFDCKVSGLPTPDLFWQLNGKPvRPDSAHKMLVRENgrhSLIIEPVTKRDAGIYTCIARNRAGEN 83


                  ....*.
gi 2024455041 207 IARGRL 212
Cdd:cd05744    84 SFNAEL 89

Fibronectin type III domain;

Pssm-ID: 394996 [Multi-domain] Cd Length: 85 Bit Score: 47.41 E-value: 1.07e-06

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 806 PPGNV-VWNVTDSRVILNWEEVRamENESEVTGYKVLYRTSGQNNM-NVLNTDKTTAEL----LLPfNEDYIIEVKATTE 879
Cdd:pfam00041   2 APSNLtVTDVTSTSLTVSWTPPP--DGNGPITGYEVEYRPKNSGEPwNEITVPGTTTSVtltgLKP-GTEYEVRVQAVNG 78


                  ....*..
gi 2024455041 880 GGDGTSS 886
Cdd:pfam00041  79 GGEGPPS 85

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: 1.36e-06

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 2024455041 134 PETLPAAKGSTVKLECFALGNPVPQINWRRtDGMPFP--SKIKLRKSNgMIEIPNFQQEDAGLYECITENSR 203
Cdd:cd20957     8 PPVQTVDFGRTAVFNCSVTGNPIHTVLWMK-DGKPLGhsSRVQILSED-VLVIPSVKREDKGMYQCFVRNDG 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: 47.38 E-value: 1.50e-06

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 2024455041 324 GSTVDFECKPKASPKARCSWKKGGEQL---HENERITLLKDGGLRITNVTKVDAGSYTCVATNQFGTASGTTNLVV 396
Cdd:cd20969    17 GHTVQFVCRADGDPPPAILWLSPRKHLvsaKSNGRLTVFPDGTLEVRYAQVQDNGTYLCIAANAGGNDSMPAHLHV 92

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: 47.26 E-value: 1.58e-06

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 2024455041 228 EIAVEDTLYWDCRASGKPKPSYRW-LKNGEQLSVEGRIQIENGALTISSLNLT-DSGRYQCIAENKHGVIYSS 298
Cdd:cd05849    15 EESTEGKVSVNCRARANPFPIYKWrKNNLDIDLTNDRYSMVGGNLVINNPDKYkDAGRYVCIVSNIYGKVRSR 87

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: 47.23 E-value: 1.74e-06

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 239 CRASGKPKPSYRWLKNGEQLSVEGRIQIEN---GALTISSLNLTDSGRYQCIAENKHGVIYSSAELRVVA 305
Cdd:cd05730    25 CDADGFPEPTMTWTKDGEPIESGEEKYSFNedgSEMTILDVDKLDEAEYTCIAENKAGEQEAEIHLKVFA 94

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: 1.76e-06

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 315 MKKMI--QVQIGSTVDFECKPKA-SPKARCSWKKGGEQL--HENERITLLKDGG---LRITNVTKVDAGSYTCVATNQFG 386
Cdd:cd05750     3 LKEMKsqTVQEGSKLVLKCEATSeNPSPRYRWFKDGKELnrKRPKNIKIRNKKKnseLQINKAKLEDSGEYTCVVENILG 82

                          90
                  ....*....|
gi 2024455041 387 TASGTTNLVV 396
Cdd:cd05750    83 KDTVTGNVTV 92

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: 46.94 E-value: 1.82e-06

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 2024455041 225 KDTEIAVEDTLYWDCRASGKPKPSYRWLKNGEQLSVEGRIQIENGALTISSLNLTDSGRYQCIAENKHG 293
Cdd:cd05851     9 KDTYALKGQNVTLECFALGNPVPVIRWRKILEPMPATAEISMSGAVLKIFNIQPEDEGTYECEAENIKG 77

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: 46.94 E-value: 1.85e-06

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 310 FSKNPmkKMIQVQIGSTVDFECKPKASPKARCSWKKGGEQLHEN----ERITLLKDGgLRITNVTKVDAGSYTCVATNQF 385
Cdd:cd20949     2 FTENA--YVTTVKEGQSATILCEVKGEPQPNVTWHFNGQPISASvadmSKYRILADG-LLINKVTQDDTGEYTCRAYQVN 78

                          90
                  ....*....|.
gi 2024455041 386 GTASGTTNLVV 396
Cdd:cd20949    79 SIASDMQERTV 89

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: 46.80 E-value: 2.03e-06

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 134 PETLPAAKGSTVKLECFA-LGNPVPQINWRRTDG-MPFPSKIKL---RKSNGMIEIPNFQQEDAGLYECITENSRGKNIA 208
Cdd:pfam00047   3 PPTVTVLEGDSATLTCSAsTGSPGPDVTWSKEGGtLIESLKVKHdngRTTQSSLLISNVTKEDAGTYTCVVNNPGGSATL 82


                  .
gi 2024455041 209 R 209
Cdd:pfam00047  83 S 83

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: 46.89 E-value: 2.05e-06

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 222 QMIKDTEIAVEDTLYWDCRASGKPKPSYRWLKNGEQLSV--EGRIQI--ENGALTISSLNLTD----SGRYQCIAENKHG 293
Cdd:cd05875     6 QSAKDYIVDPRDNILIECEAKGNPVPTFHWTRNGKFFNVakDPRVSMrrRSGTLVIDFRGGGRpedyEGEYQCFARNKFG 85


                  ....*
gi 2024455041 294 VIYSS 298
Cdd:cd05875    86 TALSN 90

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: 46.33 E-value: 2.06e-06

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 2024455041 142 GSTVKLECFALGNPVPQINWRRTDG-MPFPSKIKLRKSN--GMIEIPNFQQEDAGLYECITENSRG 204
Cdd:cd05743     1 GETVEFTCVATGVPTPIINWRLNWGhVPDSARVSITSEGgyGTLTIRDVKESDQGAYTCEAINTRG 66

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: 46.04 E-value: 2.55e-06

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|....*.
gi 2024455041 242 SGKPKPSYRWLKNGEQLSVEGRIQIENGA----LTISSLNLTDSGRYQCIAENKHG 293
Cdd:cd05748    17 KGRPTPTVTWSKDGQPLKETGRVQIETTAsstsLVIKNAKRSDSGKYTLTLKNSAG 72

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: 46.53 E-value: 2.67e-06

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 2024455041 139 AAKGSTVKLECFALGNPVPQINWRR-TDGMPFPSKIKLRKsNGMIEIPNFQQEDAGLYECITENSRGKNIARGRLT 213
Cdd:cd05852    14 AAKGGRVIIECKPKAAPKPKFSWSKgTELLVNNSRISIWD-DGSLEILNITKLDEGSYTCFAENNRGKANSTGVLS 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: 46.78 E-value: 2.76e-06

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 2024455041 321 VQIGSTVDFECKPKASPKARCSWKKGGEQL-----HENERITLLKDGGLRITNV-----TKVDAGSYTCVATNQFGTA 388
Cdd:cd07693    12 VSKGDPATLNCKAEGRPTPTIQWLKNGQPLetdkdDPRSHRIVLPSGSLFFLRVvhgrkGRSDEGVYVCVAHNSLGEA 89

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: 46.26 E-value: 2.83e-06

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 2024455041 324 GSTVDFECKPKASPKARCSWKKGGEQLHENERITLLK---DGG---LRITNVTKVDAGSYTCVATNQFGTASGTTNLVV 396
Cdd:cd20951    15 KSDAKLRVEVQGKPDPEVKWYKNGVPIDPSSIPGKYKiesEYGvhvLHIRRVTVEDSAVYSAVAKNIHGEASSSASVVV 93

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: 46.39 E-value: 3.17e-06

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 2024455041 142 GSTVKLECFALGNPVPQINWRRtDGMPF--PSKIKLRKSNGMIEIPNFQQEDAGLYECITENSRGK 205
Cdd:cd05856    19 GSSVRLKCVASGNPRPDITWLK-DNKPLtpPEIGENKKKKWTLSLKNLKPEDSGKYTCHVSNRAGE 83

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: 45.93 E-value: 3.40e-06

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 2024455041 324 GSTVDFECKPKASPKARCSW-KKGGEQLHENERITLLKDGGLRITNVTKVDAGSYTCVATNQFGTASGTTNLVV 396
Cdd:cd05764    15 GQRATLRCKARGDPEPAIHWiSPEGKLISNSSRTLVYDNGTLDILITTVKDTGAFTCIASNPAGEATARVELHI 88

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: 46.46 E-value: 3.49e-06

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....
gi 2024455041 327 VDFECKPKASPKARCSWKKGGEQLH--ENERITLLKdGGLRITNVTKV-DAGSYTCVATNQFGT 387
Cdd:cd05850    23 VTLACRARASPPATYRWKMNGTELKmePDSRYRLVA-GNLVISNPVKAkDAGSYQCLASNRRGT 85

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: 46.09 E-value: 3.53e-06

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 307 APDFSKNPMKkmIQVQIGSTVDFECKPKASPKARCSWKKGGEQL-HENERITL-LKDGGLRITNVTKVDAGSYTCVATNQ 384
Cdd:cd20976     1 APSFSSVPKD--LEAVEGQDFVAQCSARGKPVPRITWIRNAQPLqYAADRSTCeAGVGELHIQDVLPEDHGTYTCLAKNA 78

                          90
                  ....*....|..
gi 2024455041 385 FGTASGTTNLVV 396
Cdd:cd20976    79 AGQVSCSAWVTV 90

Immunoglobulin (Ig)-like domain at the C-terminus of semaphorins; The members here are composed of the immunoglobulin (Ig)-like domain in semaphorins. Semaphorins are transmembrane protein that have important roles in a variety of tissues. Functionally, semaphorins were initially characterized for their importance in the development of the nervous system and in axonal guidance. Later they have been found to be important for the formation and functioning of the cardiovascular, endocrine, gastrointestinal, hepatic, immune, musculoskeletal, renal, reproductive, and respiratory systems. Semaphorins function through binding to their receptors and transmembrane semaphorins also serves as receptors themselves. Although molecular mechanism of semaphorins is poorly understood, the Ig-like domains may be involved in ligand binding or dimerization.

Pssm-ID: 409368 Cd Length: 88 Bit Score: 45.91 E-value: 3.68e-06

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 2024455041 404 LAPSNMDVTVGESVILPCQVqhdPILDISFTWYFNGTltdfKKDASHFEKVGGSASGDLMIRNIQLKHSGKYVC 477
Cdd:cd04979     1 TSFKQISVKEGDTVILSCSV---KSNNAPVTWIHNGK----KVPRYRSPRLVLKTERGLLIRSAQEADAGVYEC 67

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: 45.86 E-value: 4.10e-06

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 308 PDFSKNPMKkmIQVQIGSTVDFECKPKASPKARCSWKKGGEQLH-ENERITLLKDGG---LRITNVTKVDAGSYTCVATN 383
Cdd:cd20990     1 PHFLQAPGD--LTVQEGKLCRMDCKVSGLPTPDLSWQLDGKPIRpDSAHKMLVRENGvhsLIIEPVTSRDAGIYTCIATN 78

                          90
                  ....*....|...
gi 2024455041 384 QFGTASGTTNLVV 396
Cdd:cd20990    79 RAGQNSFNLELVV 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: 45.86 E-value: 4.14e-06

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 218 PHWIQMIKDTEIAVEDTLYWDCRASGKPKPSYRWLKNGEQL---SVEGRIQIENG--ALTISSLNLTDSGRYQCIAENKH 292
Cdd:cd20990     1 PHFLQAPGDLTVQEGKLCRMDCKVSGLPTPDLSWQLDGKPIrpdSAHKMLVRENGvhSLIIEPVTSRDAGIYTCIATNRA 80

                          90
                  ....*....|.
gi 2024455041 293 GVIYSSAELRV 303
Cdd:cd20990    81 GQNSFNLELVV 91

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: 46.06 E-value: 4.32e-06

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 2024455041 138 PAAKGSTVKLECFALGNPVPQINWRRtDGMPF-----PSKIKLRKSNGMIEIPNFQQEDAGLYECITENSRG 204
Cdd:cd05729    15 ALPAANKVRLECGAGGNPMPNITWLK-DGKEFkkehrIGGTKVEEKGWSLIIERAIPRDKGKYTCIVENEYG 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: 45.61 E-value: 5.37e-06

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 2024455041 138 PAAKgsTVKLECFALGNPVPQINWRRtDGMPFPSK-----IKLRKSNGMIEIPNFQQEDAGLYECITENSRG 204
Cdd:cd05857    17 PAAN--TVKFRCPAAGNPTPTMRWLK-NGKEFKQEhriggYKVRNQHWSLIMESVVPSDKGNYTCVVENEYG 85

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: 45.70 E-value: 5.73e-06

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 120 GVMGEYEPkIEVQFPETLPAAKgstVKLECFALGNPVPQINWRRTDG---MPFPSKIKLRKSNGMIEIPNfQQEDAGLYE 196
Cdd:cd04967     1 GPVFEEQP-DDTIFPEDSDEKK---VALNCRARANPVPSYRWLMNGTeidLESDYRYSLVDGTLVISNPS-KAKDAGHYQ 75

                          90
                  ....*....|...
gi 2024455041 197 CITENSRGKNIAR 209
Cdd:cd04967    76 CLATNTVGSVLSR 88

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: 6.18e-06

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041  719 IEVSWKAIPWKMSSGRLLGYEVRYWNNGGKEEssnRVKAAGNETSIRITGLKSNLAYYTAVRAYNSAGAG 788
Cdd:smart00060  17 VTLSWEPPPDDGITGYIVGYRVEYREEGSEWK---EVNVTPSSTSYTLTGLKPGTEYEFRVRAVNGAGEG 83

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: 45.36 E-value: 6.97e-06

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 222 QMIKDTEIAVEDTLYWDCRASGKPKPSYRWLKNGEQLSVEGRIQI----ENGALTISSLN----LTDSGRYQCIAENKHG 293
Cdd:cd05874     6 QSPKDYIVDPRENIVIQCEAKGKPPPSFSWTRNGTHFDIDKDPKVtmkpNTGTLVINIMNgekaEAYEGVYQCTARNERG 85


                  ....*
gi 2024455041 294 VIYSS 298
Cdd:cd05874    86 AAVSN 90

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: 44.79 E-value: 7.29e-06

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 2024455041 324 GSTVDFECKPKASPKARCSWKKGGEQLHENERITLLKDGG---LRITNVTKVDAGSYTCVATNQFGTASGTTNLVVT 397
Cdd:cd05743     1 GETVEFTCVATGVPTPIINWRLNWGHVPDSARVSITSEGGygtLTIRDVKESDQGAYTCEAINTRGMVFGIPDGILT 77

Third immunoglobulin-like domain of the human WFIKKN (WAP, follistatin, immunoglobulin, Kunitz and NTR domain-containing protein), and similar domains; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the third immunoglobulin-like domain of the human WFIKKN (WAP, follistatin, immunoglobulin, Kunitz and NTR domain-containing protein) and similar proteins. WFIKKN is a secreted protein that consists of multiple types of protease inhibitory modules, including two tandem Kunitz-type protease inhibitor-domains. The Ig superfamily is a heterogenous group of proteins built on a common fold comprised of a sandwich of two beta sheets. Members of the Ig superfamily 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. 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: 409422 [Multi-domain] Cd Length: 95 Bit Score: 45.23 E-value: 7.32e-06

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 308 PDFSKNPMKKMiqVQIGSTVDFECKPKASPKARCSWKKggeQLHENERITLLKD---GGLRITNVTKV--------DAGS 376
Cdd:cd05765     1 PALVNSPTHQT--VKVGETASFHCDVTGRPQPEITWEK---QVPGKENLIMRPNhvrGNVVVTNIGQLviynaqpqDAGL 75

                          90
                  ....*....|
gi 2024455041 377 YTCVATNQFG 386
Cdd:cd05765    76 YTCTARNSGG 85

Phage-related protein, tail protein J [Mobilome: prophages, transposons];

Pssm-ID: 443767 [Multi-domain] Cd Length: 978 Bit Score: 49.94 E-value: 7.54e-06

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 482 EVDSVASAADLIVRGSPGPPEHVRVDEITDTTAQISWQEGtdnhSPVTAYTIQARTPFSVGWQ--RVTTVPDViDGNTFT 559
Cdd:COG4733   431 PVTMEAGDRYLRVRLPDGTSVARTVQSVAGRTLTVSTAYS----ETPEAGAVWAFGPDELETQlfRVVSIEEN-EDGTYT 505

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 560 TTVVDLNPwvEYEFRVVASNKIGGGEPSLPSEkVRTEEAvpeippAEVSGGGGSRSELVITWDPIPEElqngegFGYVVA 639
Cdd:COG4733   506 ITAVQHAP--EKYAAIDAGAFDDVPPQWPPVN-VTTSES------LSVVAQGTAVTTLTVSWDAPAGA------VAYEVE 570

                         170       180       190       200       210       220       230       240
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 640 FRPfGTTTWIQTVVTSpdTPRYVFRNesiLPFSPYEVKVGVYNNKGE--GPFSSITTVFSAEEEPTVAPSGVSVTSLSSS 717
Cdd:COG4733   571 WRR-DDGNWVSVPRTS--GTSFEVPG---IYAGDYEVRVRAINALGVssAWAASSETTVTGKTAPPPAPTGLTATGGLGG 644

                         250       260       270       280       290       300       310       320
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 718 vIEVSWKAIPwkmsSGRLLGYEVRYWNNGGKEeSSNRVKAAGNETSIRITGLKSNLAYYTAVRAYNSAG-AGPFSATVNA 796
Cdd:COG4733   645 -ITLSWSFPV----DADTLRTEIRYSTTGDWA-SATVAQALYPGNTYTLAGLKAGQTYYYRARAVDRSGnVSAWWVSGQA 718


                  ..
gi 2024455041 797 TT 798
Cdd:COG4733   719 SA 720

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: 44.80 E-value: 7.59e-06

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041   30 STVSVREGQGVVLLC---GTPPrageLSFAWIFNeYPSFVQEDSRRFVSQE--TGHLYIAKVEPSDVGNYTCVVTSTVTN 104
Cdd:smart00410   2 PSVTVKEGESVTLSCeasGSPP----PEVTWYKQ-GGKLLAESGRFSVSRSgsTSTLTISNVTPEDSGTYTCAATNSSGS 76

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: 44.80 E-value: 8.62e-06

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|.
gi 2024455041 324 GSTVDFECKPKaSPKARCSWKKGGEQLHENERITLLKDGGLRITNVTKVDAGSYTCVATNQ 384
Cdd:cd05873    11 GGNAELKCSPK-SNLARVVWKFQGKVLKAESPKYGLYGDGLLIFNASEADAGRYQCLSVEK 70

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: 44.76 E-value: 8.65e-06

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 2024455041 138 PAAKGSTVKLECFALGNPVPQINWRRTDGMPFPSKIKLRKSNGMIEIPNFQQEDAGLYECITENSRGK 205
Cdd:cd04969    13 LAAKGGDVIIECKPKASPKPTISWSKGTELLTNSSRICILPDGSLKIKNVTKSDEGKYTCFAVNFFGK 80

IL-beta-binding protein; Provisional

Pssm-ID: 165149 [Multi-domain] Cd Length: 326 Bit Score: 48.86 E-value: 8.67e-06

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 264 IQIENGA-LTISSLNLTDSGRYQCIAENKHGVIYSSAELRVVA---SAPDFSKNPM-------KKM----IQVQIGSTVD 328
Cdd:PHA02785   76 IPIDNGSnMLILNPTQSDSGIYICITKNETYCDMMSLNLTIVSvseSNIDLISYPQivnerstGEMvcpnINAFIASNVN 155

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 329 FECKPKASPKARcswkkggeqlheNERITLLKDGGLRITNVTKVDAGSYTCVATNQFGTASGTTNLVVTEPTRIILAPSN 408
Cdd:PHA02785  156 ADIIWSGHRRLR------------NKRLKQRTPGIITIEDVRKNDAGYYTCVLKYIYGDKTYNVTRIVKLEVRDRIIPPT 223

                         170       180       190
                  ....*....|....*....|....*....|....*...
gi 2024455041 409 MD------VTVGESVILPCQVQ-HDPILDISFTWYFNG 439
Cdd:PHA02785  224 MQlpegvvTSIGSNLTIACRVSlRPPTTDADVFWISNG 261

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: 44.70 E-value: 9.74e-06

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 2024455041  30 STVSVREGQGVVLLCGtPPRAG-ELSFAWIFNEYPsfVQEDSRRFVSQETGHLYIAKVEPSDVGNYTCVVTSTV 102
Cdd:cd05724     5 SDTQVAVGEMAVLECS-PPRGHpEPTVSWRKDGQP--LNLDNERVRIVDDGNLLIAEARKSDEGTYKCVATNMV 75

Immunoglobulin I-set domain;

Pssm-ID: 400151 [Multi-domain] Cd Length: 90 Bit Score: 44.56 E-value: 1.03e-05

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 2024455041  32 VSVREGQGVVLLC---GTPPrageLSFAWIFNEYPsfVQEDSRRFVSQETGH--LYIAKVEPSDVGNYTCVVT 99
Cdd:pfam07679  10 VEVQEGESARFTCtvtGTPD----PEVSWFKDGQP--LRSSDRFKVTYEGGTytLTISNVQPDDSGKYTCVAT 76

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: 44.78 E-value: 1.07e-05

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 310 FSKNPMKkMIQVQiGSTVDFECKPKASPKARCSWKKGGEQLHE--NERITLLKDGGLRITNVT-----KVDAGSYTCVAT 382
Cdd:cd05722     4 FLSEPSD-IVAMR-GGPVVLNCSAESDPPPKIEWKKDGVLLNLvsDERRQQLPNGSLLITSVVhskhnKPDEGFYQCVAQ 81


                  ....*.
gi 2024455041 383 N-QFGT 387
Cdd:cd05722    82 NeSLGS 87

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: 44.44 E-value: 1.14e-05

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 399 PTRIILAPSNMDVTVGESVILPCQVQHDPILDIsfTWYFNGtltdfkKDASHFEKVGGSASGDLMIRNIQLKHSGKYVCM 478
Cdd:cd20957     1 PLSATIDPPVQTVDFGRTAVFNCSVTGNPIHTV--LWMKDG------KPLGHSSRVQILSEDVLVIPSVKREDKGMYQCF 72

                          90
                  ....*....|....
gi 2024455041 479 VKTEVDSVASAADL 492
Cdd:cd20957    73 VRNDGDSAQATAEL 86

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: 44.61 E-value: 1.18e-05

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 2024455041 319 IQVQIGSTVDFECKPKASPKARCSWKKG-----GE--QLHENERITLLKDGGLRITNVTKVDAGSYTCVATNQFGT 387
Cdd:cd20954    11 ANVAAGQDVMLHCQADGFPTPTVTWKKAtgstpGEykDLLYDPNVRILPNGTLVFGHVQKENEGHYLCEAKNGIGS 86

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: 44.12 E-value: 1.44e-05

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 2024455041 334 KASPKARCSWKKGGEQLHENERI---TLLKDGGLRITNVTKVDAGSYTCVATNQFGTASGTTNLVV 396
Cdd:cd05748    17 KGRPTPTVTWSKDGQPLKETGRVqieTTASSTSLVIKNAKRSDSGKYTLTLKNSAGEKSATINVKV 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: 44.13 E-value: 1.46e-05

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 2024455041 324 GSTVDFECKPKASPKARCSWKKGGEQLHENERITLLKDGGLRITNVTKVDAGSYTCVATNQFGTASGTTNLVV 396
Cdd:cd05876    10 GQSLVLECIAEGLPTPTVKWLRPSGPLPPDRVKYQNHNKTLQLLNVGESDDGEYVCLAENSLGSARHAYYVTV 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: 44.44 E-value: 1.47e-05

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 126 EPKIevQFPETLPAAKGSTVKLECFALGNPVPQINWRR-TDGMPFPSK-------IKLRKSNGMIEIPNFQQEDAGLYEC 197
Cdd:cd05732     2 QPKI--TYLENQTAVELEQITLTCEAEGDPIPEITWRRaTRGISFEEGdldgrivVRGHARVSSLTLKDVQLTDAGRYDC 79

                          90
                  ....*....|
gi 2024455041 198 ITENSRGKNI 207
Cdd:cd05732    80 EASNRIGGDQ 89

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: 44.31 E-value: 1.54e-05

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 2024455041 221 IQMIKDTEIAVEDTLYWDCRASGkPKPSYRWLKNGEQLSVEGRIQIENG--ALTISSLNLTDSGRYQCIAEN 290
Cdd:cd05740     4 ISSNNSNPVEDKDAVTLTCEPET-QNTSYLWWFNGQSLPVTPRLTLSNGnrTLTLLNVTREDAGAYQCEISN 74

Domain C2 of human cardiac Myosin Binding Protein C and similar domains; a member of the I-set of IgSF domains; The members here are composed of the immunoglobulin (Ig) Domain C2 of human cardiac Myosin Binding Protein C (MyBP-C) and similar domains. MyBP-C is a thick filament protein involved in the regulation of muscle contraction. Mutations in cardiac MyBP-C gene are the second most frequent cause of hypertrophic cardiomyopathy. MyBP-C binds to myosin with two binding sites, one at its C-terminus and another at its N-terminus. The N-terminal binding site, consisting of immunoglobulin (lg) domains C1 and C2 connected by a flexible linker, interacts with the S2 segment of myosin in a phosphorylation-regulated manner. The C1 and C2 Ig domains can bind to and activate or inhibit the thin filament. 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 Ig domains of MyBP-C lack this strand and thus belong to the I-set of Ig superfamily domains. 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: 409559 Cd Length: 82 Bit Score: 44.16 E-value: 1.59e-05

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|...
gi 2024455041 250 RWLKNGEQLSVEGRIQIEN-GA---LTISSLNLTDSGRYQCIA 288
Cdd:cd20967    29 KWYKDGQELQSSSKVIFESiGAkrtLTVQQASLADAGEYQCVA 71

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: 1.75e-05

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 2024455041 142 GSTVKLECFALGNPVPQINWrRTDGMPF---PSKIKLRKSNGMIEIPNFQQEDAGLYECITENSRG 204
Cdd:cd04978    14 GETGELICEAEGNPQPTITW-RLNGVPIepaPEDMRRTVDGRTLIFSNLQPNDTAVYQCNASNVHG 78

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: 44.11 E-value: 1.92e-05

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 131 VQFPETLPAAKGSTVKLECFALGNPVPQINWRRtDGMPFPSKIKLRKSNG----MIEIPNFQQEDAGLYECITENSRGKN 206
Cdd:cd20972     5 IQKLRSQEVAEGSKVRLECRVTGNPTPVVRWFC-EGKELQNSPDIQIHQEgdlhSLIIAEAFEEDTGRYSCLATNSVGSD 83

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: 44.57 E-value: 2.02e-05

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 321 VQIGSTVDFECKPKASPKARCSW----KKGGEQLHEN--ERITLLKDGG----------LRITNVTKVDAGSYTCVATNQ 384
Cdd:cd05858    13 VVVGTDAEFVCKVYSDAQPHIQWlkhvEKNGSKYGPDglPYVEVLKTAGvnttdkeievLYLRNVTFEDAGEYTCLAGNS 92

                          90
                  ....*....|..
gi 2024455041 385 FGTASGTTNLVV 396
Cdd:cd05858    93 IGISHHSAWLTV 104

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: 43.92 E-value: 2.26e-05

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 2024455041 234 TLYWDCRASGKPKPSYRWLKNGEQL---SVEGRIQ-IENGALTISSLNLTDSGRYQCIAENKHGVIYSSAELRV 303
Cdd:cd20969    19 TVQFVCRADGDPPPAILWLSPRKHLvsaKSNGRLTvFPDGTLEVRYAQVQDNGTYLCIAANAGGNDSMPAHLHV 92

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: 44.08 E-value: 2.28e-05

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 127 PKIeVQFPETLPAAKGSTVKLECFALGNPVPQINWRRtDGMPFPSKIKLRKSNGMI----------EIPNFQ-QEDAGLY 195
Cdd:cd07693     1 PRI-VEHPSDLIVSKGDPATLNCKAEGRPTPTIQWLK-NGQPLETDKDDPRSHRIVlpsgslfflrVVHGRKgRSDEGVY 78

                          90
                  ....*....|....
gi 2024455041 196 ECITENSRGKNIAR 209
Cdd:cd07693    79 VCVAHNSLGEAVSR 92

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: 43.84 E-value: 2.30e-05

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 2024455041 134 PETLPAAKGSTVKLECFALGNPVPQINWRRTDGmPFPSKIK-LRK-------SNGMIEIPNFQQEDAGLYECITENSRG 204
Cdd:cd20954     8 PVDANVAAGQDVMLHCQADGFPTPTVTWKKATG-STPGEYKdLLYdpnvrilPNGTLVFGHVQKENEGHYLCEAKNGIG 85

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: 43.77 E-value: 2.36e-05

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....
gi 2024455041 327 VDFECKPKASPKARCSWKKGGEQ--LHENERITLLkDGGLRITNVTKV-DAGSYTCVATNQFGT 387
Cdd:cd04967    22 VALNCRARANPVPSYRWLMNGTEidLESDYRYSLV-DGTLVISNPSKAkDAGHYQCLATNTVGS 84

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: 43.85 E-value: 2.41e-05

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 2024455041 134 PETLPAAKGSTVKLECFALGNPVPQINWRR----TDGMPFPSKIKLRKSnGMIEIPNFQQEDAGLYECITENSRG 204
Cdd:cd05738     6 PQLKVVEKARTATMLCAASGNPDPEISWFKdflpVDTATSNGRIKQLRS-GALQIENSEESDQGKYECVATNSAG 79

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: 43.79 E-value: 2.46e-05

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 134 PETLPAAKGSTVKLECFALGNPVPQINWRR--TDGMPFPSKIKLRKS------NGMIEIPNFQQEDAGLYECITENSRGK 205
Cdd:cd05726     6 PRDQVVALGRTVTFQCETKGNPQPAIFWQKegSQNLLFPYQPPQPSSrfsvspTGDLTITNVQRSDVGYYICQALNVAGS 85


                  ....*..
gi 2024455041 206 NIARGRL 212
Cdd:cd05726    86 ILAKAQL 92

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: 43.73 E-value: 2.61e-05

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 2024455041 134 PETLPAAKGSTVKLECFALGNPVPQINWrRTDGMPFPS---KIKLRKSNGMIEIPNFQQEDAGLYECITENSRG 204
Cdd:cd05867     6 PQSHLYGPGETARLDCQVEGIPTPNITW-SINGAPIEGtdpDPRRHVSSGALILTDVQPSDTAVYQCEARNRHG 78

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: 2.78e-05

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 127 PKIEVQfPETLPAAKGSTVKLECFALGNPVPQINWRRTDGMPFPSKIKLRKSNGMIE--------IPNFQQEDAGLYECI 198
Cdd:cd05734     2 PRFVVQ-PNDQDGIYGKAVVLNCSADGYPPPTIVWKHSKGSGVPQFQHIVPLNGRIQllsngsllIKHVLEEDSGYYLCK 80

                          90
                  ....*....|.
gi 2024455041 199 TENSRGKNIAR 209
Cdd:cd05734    81 VSNDVGADISK 91

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: 43.73 E-value: 2.80e-05

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 2024455041 234 TLYWDCRASGKPKPSYRWLKNGE--QLSVEGRIQIENG---ALTISSLNLTDSGRYQCIAENKHG 293
Cdd:cd05737    18 TLNLTCNVWGDPPPEVSWLKNDQalAFLDHCNLKVEAGrtvYFTINGVSSEDSGKYGLVVKNKYG 82

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: 43.38 E-value: 2.98e-05

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 225 KDTEIAVEDTLYWDCRASGKPKPSYRWLKNGEQ---LSVEGRIQI--ENGALTISSLNLTDSGRYQCIAENKHGVIYSSA 299
Cdd:cd05763     7 HDITIRAGSTARLECAATGHPTPQIAWQKDGGTdfpAARERRMHVmpEDDVFFIVDVKIEDTGVYSCTAQNSAGSISANA 86


                  ....*
gi 2024455041 300 ELRVV 304
Cdd:cd05763    87 TLTVL 91

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: 43.23 E-value: 3.09e-05

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 141 KGSTVKLECFALGNPVPQINWRRTDGMPFP-SKIKLRKSNGMIEIPNFQQEDAGLYECITENSRGKNIAR 209
Cdd:cd05764    14 EGQRATLRCKARGDPEPAIHWISPEGKLISnSSRTLVYDNGTLDILITTVKDTGAFTCIASNPAGEATAR 83

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: 42.97 E-value: 3.11e-05

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 2024455041 239 CRASGKPKPSYRWLKNGEQLSVEGRIQIENGALTISslNLTDSGRYQCIAENKHGVIYSSAELRV 303
Cdd:cd05739    19 CVAVGAPMPYVKWMKGGEELTKEDEMPVGRNVLELT--NIYESANYTCVAISSLGMIEATAQVTV 81

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: 43.79 E-value: 3.11e-05

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 225 KDTEIAVEDTLYWDCRASGKPKPSYRWLKNGEQ--------LSVEGRIQI-ENGALTISSLNLTDSGRYQCIAENKHGVI 295
Cdd:cd05726     7 RDQVVALGRTVTFQCETKGNPQPAIFWQKEGSQnllfpyqpPQPSSRFSVsPTGDLTITNVQRSDVGYYICQALNVAGSI 86


                  ....*...
gi 2024455041 296 YSSAELRV 303
Cdd:cd05726    87 LAKAQLEV 94

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: 43.34 E-value: 3.33e-05

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 2024455041 314 PMKKMIQVQIGSTVDFECKPK-ASPKARCSWKKGGEQLHENERITLLKDG----GLRITNVTKVDAGSYTCVATN 383
Cdd:pfam00047   1 SAPPTVTVLEGDSATLTCSAStGSPGPDVTWSKEGGTLIESLKVKHDNGRttqsSLLISNVTKEDAGTYTCVVNN 75

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: 43.38 E-value: 3.37e-05

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 139 AAKGSTVKLECFALGNPVPQINWRRtDGMPFPS---KIKLRKSNGMIEIPNFQQEDAGLYECITENSRGKNIARGRLTYY 215
Cdd:cd05730    15 ANLGQSVTLACDADGFPEPTMTWTK-DGEPIESgeeKYSFNEDGSEMTILDVDKLDEAEYTCIAENKAGEQEAEIHLKVF 93


                  ..
gi 2024455041 216 AK 217
Cdd:cd05730    94 AK 95

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: 42.97 E-value: 3.63e-05

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 2024455041 320 QVQIGSTVDFECKPKASPKARCSWKKGGEQLHENERITLLKDgGLRITNVtkVDAGSYTCVATNQFGTASGTTNLVV 396
Cdd:cd05739     8 EVMPGGSVNLTCVAVGAPMPYVKWMKGGEELTKEDEMPVGRN-VLELTNI--YESANYTCVAISSLGMIEATAQVTV 81

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: 43.23 E-value: 3.65e-05

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 2024455041 239 CRASGKPKPSYRWLK-NGEQLSVEGR-IQIENGALTISSLNLTDSGRYQCIAENKHGVIYSSAELRV 303
Cdd:cd05764    22 CKARGDPEPAIHWISpEGKLISNSSRtLVYDNGTLDILITTVKDTGAFTCIASNPAGEATARVELHI 88

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: 43.16 E-value: 3.87e-05

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 2024455041 147 LECFALGNPVPQINWRRtDGMPF-PSK---IKLRKSNGMIEIPN---FQQEDAGLYECITENSRG 204
Cdd:cd05733    21 IKCEAKGNPQPTFRWTK-DGKFFdPAKdprVSMRRRSGTLVIDNhngGPEDYQGEYQCYASNELG 84

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: 43.46 E-value: 4.00e-05

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 2024455041 243 GKPKPSYRWLKNGEQLSVEGR-----------IQIENGALTISSLNLTDSGRYQCIAENKHGVIYSSAELRVVA 305
Cdd:cd20950    24 GSPPSEYTWFKDGVVMPTNPKstrafsnssysLDPTTGELVFDPLSASDTGEYSCEARNGYGTPMRSNAVRMEA 97

Immunoglobulin (Ig)-like domain at the C-terminus of semaphorins; The members here are composed of the immunoglobulin (Ig)-like domain in semaphorins. Semaphorins are transmembrane protein that have important roles in a variety of tissues. Functionally, semaphorins were initially characterized for their importance in the development of the nervous system and in axonal guidance. Later they have been found to be important for the formation and functioning of the cardiovascular, endocrine, gastrointestinal, hepatic, immune, musculoskeletal, renal, reproductive, and respiratory systems. Semaphorins function through binding to their receptors and transmembrane semaphorins also serves as receptors themselves. Although molecular mechanism of semaphorins is poorly understood, the Ig-like domains may be involved in ligand binding or dimerization.

Pssm-ID: 409368 Cd Length: 88 Bit Score: 42.83 E-value: 4.36e-05

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 316 KKMIQVQIGSTVDFECKPKaSPKARCSWK--KGGEQLHENERITLLKDGGLRITNVTKVDAGSYTCVATNQfgtASGTTN 393
Cdd:cd04979     3 FKQISVKEGDTVILSCSVK-SNNAPVTWIhnGKKVPRYRSPRLVLKTERGLLIRSAQEADAGVYECHSGER---VLGSTL 78


                  ....
gi 2024455041 394 LVVT 397
Cdd:cd04979    79 RSVT 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: 43.06 E-value: 4.88e-05

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 2024455041 224 IKDTEIAVEDTLYWDCRASGK-PKPSYRWLKNGEQLSVEGR---IQIEN----GALTISSLNLTDSGRYQCIAENKHG 293
Cdd:cd05895     6 MKSQEVAAGSKLVLRCETSSEyPSLRFKWFKNGKEINRKNKpenIKIQKkkkkSELRINKASLADSGEYMCKVSSKLG 83

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: 42.60 E-value: 5.07e-05

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041  603 PPAEVSGGGGSRSELVITWDPIPEELQNGEGFGYVVAFRPFGTTTwiQTVVTSPDTPRYVFRNesILPFSPYEVKVGVYN 682
Cdd:smart00060   3 PPSNLRVTDVTSTSVTLSWEPPPDDGITGYIVGYRVEYREEGSEW--KEVNVTPSSTSYTLTG--LKPGTEYEFRVRAVN 78


                   ....*
gi 2024455041  683 NKGEG 687
Cdd:smart00060  79 GAGEG 83

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: 42.73 E-value: 5.20e-05

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 2024455041 233 DTLYWDCRASGKPKPSYRWLKNGEQLSVEGRIQIEN----GALTISSLNLTDSGRYQCIAENKHG 293
Cdd:cd05747    19 ESARFSCDVDGEPAPTVTWMREGQIIVSSQRHQITSteykSTFEISKVQMSDEGNYTVVVENSEG 83

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: 42.63 E-value: 6.25e-05

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 399 PTRIILAPSNMDVTVGESVILPCQVQHDpiLDISFTWyfngtlTDFKK---DASHFEKVGGSASGDLMIRNIQLKHSGKY 475
Cdd:cd05762     1 PPQIIQFPEDMKVRAGESVELFCKVTGT--QPITCTW------MKFRKqiqEGEGIKIENTENSSKLTITEGQQEHCGCY 72

                          90       100
                  ....*....|....*....|....*.
gi 2024455041 476 VCMVKTEVDSVASAADLIVRGSPGPP 501
Cdd:cd05762    73 TLEVENKLGSRQAQVNLTVVDKPDPP 98

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: 42.39 E-value: 6.69e-05

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 131 VQFPETLPAAKGSTVKLECFALGNPVPQINWrRTDGMPF---PSKIKLRKSNGM--IEIPNFQQEDAGLYECITENSRGK 205
Cdd:cd20990     4 LQAPGDLTVQEGKLCRMDCKVSGLPTPDLSW-QLDGKPIrpdSAHKMLVRENGVhsLIIEPVTSRDAGIYTCIATNRAGQ 82


                  .
gi 2024455041 206 N 206
Cdd:cd20990    83 N 83

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: 42.31 E-value: 6.78e-05

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 331 CKPKASPKARCSWKKGG---EQLHENERITLLKDGGLRITNVTKVDAGSYTCVATNQFGTA-SGTTNLVV 396
Cdd:cd05738    21 CAASGNPDPEISWFKDFlpvDTATSNGRIKQLRSGALQIENSEESDQGKYECVATNSAGTRySAPANLYV 90

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: 42.38 E-value: 7.81e-05

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 2024455041 142 GSTVKLECFALGNPVPQINW--RRTDGMPFPSKIKLRK-SNGMIEIPNFQQEDAGLYECITENSRGK 205
Cdd:cd20969    17 GHTVQFVCRADGDPPPAILWlsPRKHLVSAKSNGRLTVfPDGTLEVRYAQVQDNGTYLCIAANAGGN 83

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: 42.06 E-value: 8.46e-05

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 131 VQFPETLPAAKGSTVKLECFALGNPVPQINWRRTDGMPF--PSKIKLRKSN-GMIE--IPNFQQEDAGLYECITENSRGK 205
Cdd:cd05892     4 IQKPQNKKVLEGDPVRLECQISAIPPPQIFWKKNNEMLQynTDRISLYQDNcGRICllIQNANKKDAGWYTVSAVNEAGV 83


                  ....*..
gi 2024455041 206 NIARGRL 212
Cdd:cd05892    84 VSCNARL 90

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: 41.90 E-value: 1.20e-04

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 317 KMIQVQIGSTVDFECKPKAS-PKARCSWKKGGEQL---HENERITLLKDGG---LRITNVTKVDAGSYTCVATNQFGTAS 389
Cdd:cd05895     7 KSQEVAAGSKLVLRCETSSEyPSLRFKWFKNGKEInrkNKPENIKIQKKKKkseLRINKASLADSGEYMCKVSSKLGNDS 86


                  ....*..
gi 2024455041 390 GTTNLVV 396
Cdd:cd05895    87 ASANVTI 93

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: 41.44 E-value: 1.26e-04

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|.
gi 2024455041 234 TLYWDCRASGKPKPSYRWLK-NGEQLSVEGRIQIENGALTISSLNLTDSGRYQCIAENKHG 293
Cdd:cd05876    12 SLVLECIAEGLPTPTVKWLRpSGPLPPDRVKYQNHNKTLQLLNVGESDDGEYVCLAENSLG 72

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: 42.26 E-value: 1.26e-04

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 142 GSTVKLECFALGNPVPQINWRRTDGMPFPSKIKL----------------RKSNGMIEIPNFQQEDAGLYECITENSRGK 205
Cdd:cd20940    15 GDSVELHCEAVGSPIPEIQWWFEGQEPNEICSQLwdgarldrvhinatyhQHATSTISIDNLTEEDTGTYECRASNDPDR 94

                          90
                  ....*....|....*..
gi 2024455041 206 NiargRLTYYAKPHWIQ 222
Cdd:cd20940    95 N----HLTRAPKVKWIR 107

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: 41.41 E-value: 1.27e-04

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 404 LAPSNMDVTVGESVILPCQVqHDPILDISFTWYFNGTLTDFKKDASHFEKVGGSASgdLMIRNIQLKHSGKYVCMVKTEV 483
Cdd:pfam00047   1 SAPPTVTVLEGDSATLTCSA-STGSPGPDVTWSKEGGTLIESLKVKHDNGRTTQSS--LLISNVTKEDAGTYTCVVNNPG 77


                  ...
gi 2024455041 484 DSV 486
Cdd:pfam00047  78 GSA 80

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: 1.30e-04

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 134 PETLPAAKGSTVKLECFALGNPVPQINWRRTDGMPFPS---KIkLRKSNgmIEIPNFQQEDAGLYECITENSRGKNIARG 210
Cdd:cd05723     4 PSNIYAHESMDIVFECEVTGKPTPTVKWVKNGDVVIPSdyfKI-VKEHN--LQVLGLVKSDEGFYQCIAENDVGNAQASA 80


                  ..
gi 2024455041 211 RL 212
Cdd:cd05723    81 QL 82

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: 41.73 E-value: 1.35e-04

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 139 AAKGSTVKLECFALG-NPVPQINWRRtDGMPF----PSKIKLRKS--NGMIEIPNFQQEDAGLYECITENSRGKNIARGR 211
Cdd:cd05750    11 VQEGSKLVLKCEATSeNPSPRYRWFK-DGKELnrkrPKNIKIRNKkkNSELQINKAKLEDSGEYTCVVENILGKDTVTGN 89


                  ..
gi 2024455041 212 LT 213
Cdd:cd05750    90 VT 91

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: 41.43 E-value: 1.39e-04

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 2024455041 234 TLYWDCRASGKPKPSYRWLKNGE--QLSVEGRIQIENG---ALTISSLNLTDSGRYQCIAENKHG 293
Cdd:cd05891    18 TLNLTCTVFGNPDPEVIWFKNDQdiELSEHYSVKLEQGkyaSLTIKGVTSEDSGKYSINVKNKYG 82

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: 41.71 E-value: 1.49e-04

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 2024455041 243 GKPKPSYRWLKNGEQLSVE-----GRIQIENGALTISSLNLTDSGRYQCIAENKHGVIYSSAELRV 303
Cdd:cd20959    29 GDLPLNIRWTLDGQPISDDlgitvSRLGRRSSILSIDSLEASHAGNYTCHARNSAGSASYTAPLTV 94

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: 41.87 E-value: 1.55e-04

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 127 PKIEVQFPETLPAAKGSTVKLECFALGNPVPQINWRR----------TDGMPFPSKIK---LRKSNGMIEI---PNFQQE 190
Cdd:cd05858     1 PILQAGLPANTSVVVGTDAEFVCKVYSDAQPHIQWLKhvekngskygPDGLPYVEVLKtagVNTTDKEIEVlylRNVTFE 80

                          90
                  ....*....|....
gi 2024455041 191 DAGLYECITENSRG 204
Cdd:cd05858    81 DAGEYTCLAGNSIG 94

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: 40.78 E-value: 1.57e-04

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|...
gi 2024455041  40 VVLLC---GTPPrageLSFAWIFNEYPSFVQEDSRRFVSQETGHLYIAKVEPSDVGNYTCVVT 99
Cdd:cd00096     1 VTLTCsasGNPP----PTITWYKNGKPLPPSSRDSRRSELGNGTLTISNVTLEDSGTYTCVAS 59

Immunoglobulin (Ig)-like I-set domain of Neural Cell Adhesion Molecule 2 (NCAM-2); The members here are composed of the fourth Ig domain of Neural Cell Adhesion Molecule NCAM-2 (also known as OCAM/mamFas II and RNCAM). NCAM-2 is organized similarly to NCAM, including five N-terminal Ig-like domains and two fibronectin type III domains. NCAM-2 is differentially expressed in the developing and mature olfactory epithelium (OE), and may function like NCAM, as an adhesion molecule. 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: 143278 [Multi-domain] Cd Length: 98 Bit Score: 41.50 E-value: 1.61e-04

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 2024455041 139 AAKGSTVKLECFALGNPVPQINWRR-TDGMPFPS---------KIKLRKSNGMIEIPNFQQEDAGLYEC 197
Cdd:cd05870    13 TVENGAATLSCKAEGEPIPEITWKRaSDGHTFSEgdkspdgriEVKGQHGESSLHIKDVKLSDSGRYDC 81

Immunoglobulin (Ig)-like I-set domain of Neural Cell Adhesion Molecule 2 (NCAM-2); The members here are composed of the fourth Ig domain of Neural Cell Adhesion Molecule NCAM-2 (also known as OCAM/mamFas II and RNCAM). NCAM-2 is organized similarly to NCAM, including five N-terminal Ig-like domains and two fibronectin type III domains. NCAM-2 is differentially expressed in the developing and mature olfactory epithelium (OE), and may function like NCAM, as an adhesion molecule. 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: 143278 [Multi-domain] Cd Length: 98 Bit Score: 41.50 E-value: 1.62e-04

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 217 KPHWIQMIKDTeiAVEDT-LYWDCRASGKPKPSYRW--------LKNGEQlSVEGRIQIE----NGALTISSLNLTDSGR 283
Cdd:cd05870     2 QPHIIQLKNET--TVENGaATLSCKAEGEPIPEITWkrasdghtFSEGDK-SPDGRIEVKgqhgESSLHIKDVKLSDSGR 78

                          90
                  ....*....|
gi 2024455041 284 YQCIAENKHG 293
Cdd:cd05870    79 YDCEAASRIG 88

First 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: 409474 Cd Length: 92 Bit Score: 41.62 E-value: 1.62e-04

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|.
gi 2024455041 239 CRASGKPKPSYRWLKNGEQLSVEG---RIQIE---NGALTISSLNLTDSGRYQCIAENKHGVIYSSAELRV 303
Cdd:cd05893    22 CRVAGNPKPKIYWFKDGKQISPKSdhyTIQRDldgTCSLHTTASTLDDDGNYTIMAANPQGRISCTGRLMV 92

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: 41.18 E-value: 1.77e-04

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 2024455041 233 DTLYWDCRASGKPKPSYRWLKNGE--QLSVEGRIQIENGA----LTISSLNLTDSGRYQCIAENKHGVIYSSAELRV 303
Cdd:cd20974    16 STATFEAHVSGKPVPEVSWFRDGQviSTSTLPGVQISFSDgrakLSIPAVTKANSGRYSLTATNGSGQATSTAELLV 92

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: 41.40 E-value: 1.86e-04

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 2024455041 238 DCRASGKPKP-SYRWLKNGEQLSVEGR--IQIEN-GALTISSLNLTDSGRYQCIAENKHGVIYSSA 299
Cdd:cd20979    21 ECVTEGGDQGvKYSWLKDGKSFNWQEHnvAQRKDeGSLVFLKPQASDEGQYQCFAETPAGVASSRV 86

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: 41.03 E-value: 2.00e-04

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 2024455041 124 EYEPKIEVQFPETLPAAKGSTVKLECfALGNPVPQINWRRtDGMPFPSKIKLRKSNGMIEIPNFQQEDAGLYECIT 199
Cdd:cd04973     6 EAPPTYQISEVESYSAHPGDLLQLRC-RLRDDVQSINWTK-DGVQLGENNRTRITGEEVQIKDAVPRDSGLYACVT 79

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: 40.46 E-value: 2.77e-04

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 325 STVDFECKPkASPKARCSWKKGGEQLHENERITLLKDGG-LRITNVTKVDAGSYTCVATN 383
Cdd:cd05740    16 DAVTLTCEP-ETQNTSYLWWFNGQSLPVTPRLTLSNGNRtLTLLNVTREDAGAYQCEISN 74

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: 39.79 E-value: 3.58e-04

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 2024455041 142 GSTVKLECFALGNPVPQINWRRTDgmpfpskiKLRKSNGMIEIPNFQQEDAGLYECITENS-RGKNI 207
Cdd:cd20948    10 GENLNLSCHAASNPPAQYSWTING--------TFQTSSQELFLPAITENNEGTYTCSAHNSlTGKNI 68

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: 40.17 E-value: 3.78e-04

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 403 ILAPSNMDVTVGESVILPCQVQHDPILDIsfTWYFNGTLTDFkkDASHFEKVGGSASGDLMIRNIQLKHSGKYVCMVKTE 482
Cdd:cd05744     4 LQAPGDLEVQEGRLCRFDCKVSGLPTPDL--FWQLNGKPVRP--DSAHKMLVRENGRHSLIIEPVTKRDAGIYTCIARNR 79

                          90
                  ....*....|..
gi 2024455041 483 VDSVASAADLIV 494
Cdd:cd05744    80 AGENSFNAELVV 91

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: 40.30 E-value: 3.88e-04

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 228 EIAVEDTLYWDCRASGKPKPSYRWLKNGEQLSVEGriqienGALTISS--LNLT-------DSGRYQCIAENKHGVIYSS 298
Cdd:cd05760    12 EIQPSSRVTLRCHIDGHPRPTYQWFRDGTPLSDGQ------GNYSVSSkeRTLTlrsagpdDSGLYYCCAHNAFGSVCSS 85

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: 40.24 E-value: 4.10e-04

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 2024455041 142 GSTVKLECFALGNPVPQINWRRtDGMPFPSKIKLR-KSNGMIEIPNFQQ-EDAGLYECITENSRGkNIARGRL 212
Cdd:cd20958    15 GQTLRLHCPVAGYPISSITWEK-DGRRLPLNHRQRvFPNGTLVIENVQRsSDEGEYTCTARNQQG-QSASRSV 85

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: 40.31 E-value: 4.25e-04

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 2024455041 145 VKLECFALGNPVPQINWRRtDGMPFPSKIKLRKS----NGMIEIPNfQQEDAGLYECITENSRGKNIARGRLTYYA 216
Cdd:cd05848    22 VILNCEARGNPVPTYRWLR-NGTEIDTESDYRYSlidgNLIISNPS-EVKDSGRYQCLATNSIGSILSREALLQFA 95

First immunoglobulin (Ig)-like domain of Fcgamma-receptors (FcgammaRs), and similar domains; The members here are composed of the first immunoglobulin (Ig)-like domain of Fcgamma-receptors (FcgammaRs). Interactions between IgG and FcgammaR are important to the initiation of cellular and humoral response. IgG binding to FcgammaR leads to a cascade of signals and ultimately to functions such as antibody-dependent-cellular-cytotoxicity (ADCC), endocytosis, phagocytosis, release of inflammatory mediators, etc. FcgammaR has two Ig-like domains. This group also contains FcepsilonRI which binds IgE with high affinity.

Pssm-ID: 409410 [Multi-domain] Cd Length: 79 Bit Score: 39.65 E-value: 4.36e-04

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....
gi 2024455041 414 GESVILPCQVQHDPiLDISFTWYFNGTLTdfKKDASHFEkvggsasgdlmIRNIQLKHSGKYVC 477
Cdd:cd05752    15 GEKVTLTCQGFYSP-EQNSTQWYHNGTLI--SSTSSSYR-----------IVAATVNDSGEYRC 64

Immunoglobulin domain; This domain contains immunoglobulin-like domains.

Pssm-ID: 464026 [Multi-domain] Cd Length: 79 Bit Score: 39.69 E-value: 4.52e-04

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 2024455041 127 PKIEvqfPETLPAAKGSTVKLECFALGNPVPQINWRRtDGMPFPskiklrkSNGMIEIPNFQQEDAGLYECITENSRGK 205
Cdd:pfam13895   2 PVLT---PSPTVVTEGEPVTLTCSAPGNPPPSYTWYK-DGSAIS-------SSPNFFTLSVSAEDSGTYTCVARNGRGG 69

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: 40.15 E-value: 4.53e-04

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 134 PETLPAAKGSTVKLECFALGNPVPQINWRRtDGMPFPSKIKLRK---SNGMIEIPNFQ-----QEDAGLYECITEN-SRG 204
Cdd:cd05722     8 PSDIVAMRGGPVVLNCSAESDPPPKIEWKK-DGVLLNLVSDERRqqlPNGSLLITSVVhskhnKPDEGFYQCVAQNeSLG 86

                          90
                  ....*....|
gi 2024455041 205 KNIAR-GRLT 213
Cdd:cd05722    87 SIVSRtARVT 96

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: 40.18 E-value: 4.66e-04

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 395 VVTEPTRiilaPSNMDVTVGESVILPCQVQHDPILDISftWYFNGTLTdfkKDASHFEKVGGSASgDLMIRNIQLKHSGK 474
Cdd:cd20970     2 VISTPQP----SFTVTAREGENATFMCRAEGSPEPEIS--WTRNGNLI---IEFNTRYIVRENGT-TLTIRNIRRSDMGI 71

                          90       100
                  ....*....|....*....|.
gi 2024455041 475 YVCMVKTEVD-SVASAADLIV 494
Cdd:cd20970    72 YLCIASNGVPgSVEKRITLQV 92

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: 40.01 E-value: 5.29e-04

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 2024455041 239 CRASGKPKPSYRWLKNGEQLSVE----GRIQIENGALTISSLNLTDSGRYQCIAENKHGVIYSSAELRV 303
Cdd:cd20949    21 CEVKGEPQPNVTWHFNGQPISASvadmSKYRILADGLLINKVTQDDTGEYTCRAYQVNSIASDMQERTV 89

First 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: 409474 Cd Length: 92 Bit Score: 39.70 E-value: 6.31e-04

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 2024455041 324 GSTVDFECKPKASPKARCSWKKGGEQLH-ENERITLLKD----GGLRITNVTKVDAGSYTCVATNQFGTASGTTNLVV 396
Cdd:cd05893    15 GMPVTFTCRVAGNPKPKIYWFKDGKQISpKSDHYTIQRDldgtCSLHTTASTLDDDGNYTIMAANPQGRISCTGRLMV 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: 39.85 E-value: 6.32e-04

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 2024455041 321 VQIGSTVDFECKPKASPKARCSWKKGGEQLHENERI------TLLKD--GGLRITNVTKVDAGSYTCVATNQFGTAS 389
Cdd:cd20956    13 LQPGPSVSLKCVASGNPLPQITWTLDGFPIPESPRFrvgdyvTSDGDvvSYVNISSVRVEDGGEYTCTATNDVGSVS 89

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: 39.84 E-value: 7.12e-04

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041  30 STVSVREGQGVVLLC-GTPPRAGELSFAWIFNEYPSFVQEDS----RRFVSQETGHLYIAKVEPSDVGNYTCVVTSTVTN 104
Cdd:cd04970    10 SNADITVGENATLQChASHDPTLDLTFTWSFNGVPIDLEKIEghyrRRYGKDSNGDLEIVNAQLKHAGRYTCTAQTVVDS 89


                  .
gi 2024455041 105 S 105
Cdd:cd04970    90 D 90

Third immunoglobulin-like domain of the human WFIKKN (WAP, follistatin, immunoglobulin, Kunitz and NTR domain-containing protein), and similar domains; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the third immunoglobulin-like domain of the human WFIKKN (WAP, follistatin, immunoglobulin, Kunitz and NTR domain-containing protein) and similar proteins. WFIKKN is a secreted protein that consists of multiple types of protease inhibitory modules, including two tandem Kunitz-type protease inhibitor-domains. The Ig superfamily is a heterogenous group of proteins built on a common fold comprised of a sandwich of two beta sheets. Members of the Ig superfamily 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. 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: 409422 [Multi-domain] Cd Length: 95 Bit Score: 39.84 E-value: 7.18e-04

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 229 IAVEDTLYWDCRASGKPKPSYRWLKNGEQLS--------VEGRIQIEN-GALTISSLNLTDSGRYQCIAENKHGVIYSSA 299
Cdd:cd05765    12 VKVGETASFHCDVTGRPQPEITWEKQVPGKEnlimrpnhVRGNVVVTNiGQLVIYNAQPQDAGLYTCTARNSGGLLRANF 91


                  ....
gi 2024455041 300 ELRV 303
Cdd:cd05765    92 PLSV 95

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: 39.60 E-value: 7.62e-04

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 218 PHWIQMIKDTEIAVEDTLYWDCRASGKPKPSYRWLKN-----GE--QLSVEGRIQI-ENGALTISSLNLTDSGRYQCIAE 289
Cdd:cd20954     2 PRWIVEPVDANVAAGQDVMLHCQADGFPTPTVTWKKAtgstpGEykDLLYDPNVRIlPNGTLVFGHVQKENEGHYLCEAK 81


                  .
gi 2024455041 290 N 290
Cdd:cd20954    82 N 82

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: 38.70 E-value: 7.64e-04

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|.
gi 2024455041 145 VKLECFALGNPVPQINWRRtDGMPFPSKIKLRKS-NGMIEIPNFQQEDAGLYECITENSRG 204
Cdd:cd05746     1 VQIPCSAQGDPEPTITWNK-DGVQVTESGKFHISpEGYLAIRDVGVADQGRYECVARNTIG 60

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: 39.64 E-value: 7.90e-04

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 321 VQIGSTVDFECKPKASPKARCSWKKGGE--QLHENERITL-LKDGG--LRITNVTKVDAGSYTCVATNQFGTASGTTNLV 395
Cdd:cd20974    12 VLEGSTATFEAHVSGKPVPEVSWFRDGQviSTSTLPGVQIsFSDGRakLSIPAVTKANSGRYSLTATNGSGQATSTAELL 91


                  ..
gi 2024455041 396 VT 397
Cdd:cd20974    92 VL 93

First immunoglobulin (Ig)-like domain of neural cell adhesion molecule NCAM-1, 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 of neural cell adhesion molecule NCAM-1. NCAM-1 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-nonNCAM) 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 the Ig1, Ig2, and Ig3 domains. 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). 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: 409366 Cd Length: 95 Bit Score: 39.54 E-value: 7.97e-04

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 2024455041 228 EIAVEDTLYWDCRASGKPKpSYRWLK-NGEQL-SVEGRIQIEN-----GALTISSLNLTDSGRYQCIAENKHG 293
Cdd:cd04977    11 EISVGESKFFLCKVSGDAK-NINWVSpNGEKVlTKHGNLKVVNhgsvlSSLTIYNANINDAGIYKCVATNGKG 82

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: 39.57 E-value: 8.85e-04

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|.
gi 2024455041 147 LECFALGNPVPQINWRRtDGMPF----PSKIKLRKSNGMIEIpNFQ-----QEDAGLYECITENSRGKNIA 208
Cdd:cd05875    21 IECEAKGNPVPTFHWTR-NGKFFnvakDPRVSMRRRSGTLVI-DFRgggrpEDYEGEYQCFARNKFGTALS 89

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: 39.37 E-value: 9.26e-04

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 218 PHWIQMIKDTEIAVEDTLYWDCRASGKPKPSYRWLKNGEQLSVE-----------GRIqiengALTISSLNLTDSGRYQC 286
Cdd:cd05892     1 PMFIQKPQNKKVLEGDPVRLECQISAIPPPQIFWKKNNEMLQYNtdrislyqdncGRI-----CLLIQNANKKDAGWYTV 75

                          90
                  ....*....|....*..
gi 2024455041 287 IAENKHGVIYSSAELRV 303
Cdd:cd05892    76 SAVNEAGVVSCNARLDV 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: 39.16 E-value: 9.43e-04

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 2024455041  36 EGQGVVLLC---GTP-PRagelsFAWIFNEYPsfVQEDSRRF-VSQETGHLYIAKVEPSDVGNYTCV 97
Cdd:cd20976    15 EGQDFVAQCsarGKPvPR-----ITWIRNAQP--LQYAADRStCEAGVGELHIQDVLPEDHGTYTCL 74

First immunoglobulin (Ig)-like domain of neural cell adhesion molecule (NCAM-1); member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the first immunoglobulin (Ig)-like domain of neural cell adhesion molecule (NCAM-1). NCAM-1 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-nonNCAM), 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 the Ig1, Ig2, and Ig3 domains. 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. 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: 409451 Cd Length: 97 Bit Score: 39.25 E-value: 1.05e-03

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 320 QVQIGSTVDFECKPKASPKAR-CSW-KKGGEQLHENE-RITLLKD----GGLRITNVTKVDAGSYTCVATNQFGTAS-GT 391
Cdd:cd05865    11 EISVGESKFFLCQVAGEAKDKdISWfSPNGEKLTPNQqRISVVRNddysSTLTIYNANIDDAGIYKCVVSNEDEGESeAT 90


                  ...
gi 2024455041 392 TNL 394
Cdd:cd05865    91 VNV 93

Immunoglobulin (Ig)-like domain of vascular endothelial growth factor (VEGF) receptor(R); member of the I-set of IgSF domains; The members here are composed of the immunoglobulin (Ig)-like domain of vascular endothelial growth factor (VEGF) receptor(R). 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 (also known as Flt-1), VEGFR-2 (also known as KDR or Flk-1) and VEGFR-3 (also known as Flt-4). VEGF_A interacts with both VEGFR-1 and VEGFR-2. VEGFR-1 binds strongest to VEGF, VEGF-2 binds more weakly. VEGFR-3 appears not to bind VEGF, but binds other members of the VEGF family (VEGF-C and -D). VEGFRs bind VEGFs with high affinity with 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-2 and -1 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.

Pssm-ID: 409448 Cd Length: 102 Bit Score: 39.35 E-value: 1.05e-03

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 403 ILAPSNMDVTVGESVILPCQVQHDPILDISFTWYFNG--------TLTDFKKDASHFEKVggsaSGDLMIRNIQLKHSGK 474
Cdd:cd05862     5 LSPPKPVELLVGEKLVLNCTARTELNVGVDFQWDYPGkkeqrrasVRRRRKQQSSEATEF----SSTLTIDNVTLSDKGL 80

                          90       100
                  ....*....|....*....|
gi 2024455041 475 YVCMVKTEVDSVASAADLIV 494
Cdd:cd05862    81 YTCAASSGPMFKKNSTSVIV 100

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: 39.14 E-value: 1.08e-03

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 2024455041 315 MKKMIQVQIGSTVDFECKPKASPKARCSWKKGGEQLheNERITLLKDGGLRITNVTKVDAGSYTCVATN 383
Cdd:cd05864     8 MESLVEAKVGERVRIPVKYLGYPPPEIKWYKNGIPI--ESNHTIKAGHVLTIMEVTEKDAGNYTVVLTN 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: 39.17 E-value: 1.22e-03

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 308 PDFSKNPMKKMI-QVQIGSTVDFECKPKASPKARCSWKKggeqlhENERITLLKD------GGLRITNVTKV-DAGSYTC 379
Cdd:cd05849     2 PVFEEQPIDTIYpEESTEGKVSVNCRARANPFPIYKWRK------NNLDIDLTNDrysmvgGNLVINNPDKYkDAGRYVC 75

                          90
                  ....*....|..
gi 2024455041 380 VATNQFGTASGT 391
Cdd:cd05849    76 IVSNIYGKVRSR 87

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: 38.54 E-value: 1.74e-03

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 326 TVDFE-CKP---KASPKARCSWKKGGEQLHENERI-TLLKD---------GGLRITNVTKVDAGSYTCVATNQFGTASGT 391
Cdd:cd04971    11 ELRHHwCIPftvRGNPKPTLTWYHNGAVLNESDYIrTEIHYeaatpteyhGCLKFDNPTHVNNGNYTLVASNEYGQDSKS 90

Immunoglobulin Variable (V) domain of the Coxsackievirus and Adenovirus Receptor (CAR), and similar proteins; The members here are composed of the Variable (V) domain of the Coxsackievirus and Adenovirus Receptor (CAR), and similar proteins. CAR, which is encoded by human CXADR gene, is a cell adhesion molecule of the Immunoglobulin (Ig) superfamily. The CAR acts as a type I membrane receptor for group B1-B6 coxsackie viruses and subgroup C adenoviruses. For instance, adenovirus interacts with the coxsackievirus and adenovirus receptor to enter epithelial airway cells. The CAR is also shown to be involved in physiological processes such as neuronal and heart development, epithelial tight junction integrity, and tumor suppression. The CAR is a component of the epithelial apical junction complex that may function as a homophilic cell adhesion molecule and is essential for tight junction integrity. The CAR is also involved in transepithelial migration of leukocytes through adhesive interactions with JAML a transmembrane protein of the plasma membrane of leukocytes. The interaction between both receptors also mediates the activation of gamma-delta T-cells, a subpopulation of T-cells residing in epithelia and involved in tissue homeostasis and repair. The CAR is composed of one V-set and one C2-set Ig module, a single transmembrane helix, and an intracellular domain. This group belongs to the V-set of IgSF domains, having A, B, E and D strands in one beta-sheet and A', G, F, C, C' and C" in the other

Pssm-ID: 409552 Cd Length: 114 Bit Score: 38.97 E-value: 1.81e-03

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 402 IILAPSNMDVTVGESVILPCQVQ----HDPILDISftW--------------YFNG----TLTDFKKDASHFekVGGSAS 459
Cdd:cd20960     3 ITSAQTEIKKVAGENVTLPCHHQlgleDQGTLDIE--WlllpsdkvekvvitYSGDrvynHYYPALKGRVAF--TSNDLS 78

                          90       100
                  ....*....|....*....|....
gi 2024455041 460 GD--LMIRNIQLKHSGKYVCMVKT 481
Cdd:cd20960    79 GDasLNISNLKLSDTGTYQCKVKK 102

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: 38.44 E-value: 1.92e-03

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 408 NMDVTVGESVILPCQ-VQHDPILdiSFTWYFNGTLTDFKKDASHFEKVGGSASGDLMIRNIQLKHSGKYVCMVKTEVDSV 486
Cdd:cd05895     8 SQEVAAGSKLVLRCEtSSEYPSL--RFKWFKNGKEINRKNKPENIKIQKKKKKSELRINKASLADSGEYMCKVSSKLGND 85


                  ....*...
gi 2024455041 487 ASAADLIV 494
Cdd:cd05895    86 SASANVTI 93

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: 38.42 E-value: 2.00e-03

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 2024455041 134 PETLPAAKGSTVKLECFALGNPVPQINWrRTDGMPF---PSKIKLRKSNGMIEIPNFQQEDAGLYECITENSRGKNIA 208
Cdd:cd05868     6 PTNLVLSPGEDGTLICRANGNPKPSISW-LTNGVPIeiaPTDPSRKVDGDTIIFSKVQERSSAVYQCNASNEYGYLLA 82

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: 38.38 E-value: 2.22e-03

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 2024455041 324 GSTVDFECK-PKASPKARCSWKKggeQLHENE---------RITLLKDGGLRITNVTKVDAGS---YTCVATN 383
Cdd:cd20965    17 GKPFKLDCNvPPGYPKPTIEWKK---QLVSDSskadtildrRITISPNGDLYFTNVTKEDVSTdykYVCVAKT 86

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: 37.61 E-value: 2.39e-03

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|....*..
gi 2024455041 141 KGSTVKLECFALGNPVPQINWRRTDGMPFPSKIKLRKSNGMIEIPNFQQEDAGLYEC 197
Cdd:cd05745     1 EGQTVDFLCEAQGYPQPVIAWTKGGSQLSVDRRHLVLSSGTLRISRVALHDQGQYEC 57

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: 38.01 E-value: 2.63e-03

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 126 EPKIEVQFPETLPAAKgstVKLECFALGNPVPQINWRRTDGMPFPSKIKLRKSNGMIEIPN-FQQEDAGLYECITENSRG 204
Cdd:cd05849     6 EQPIDTIYPEESTEGK---VSVNCRARANPFPIYKWRKNNLDIDLTNDRYSMVGGNLVINNpDKYKDAGRYVCIVSNIYG 82


                  .
gi 2024455041 205 K 205
Cdd:cd05849    83 K 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: 38.00 E-value: 2.66e-03

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....
gi 2024455041 327 VDFECKPKASPKARCSWKKGGEQ--LHENERITLLkDGGLRITNVTKV-DAGSYTCVATNQFGT 387
Cdd:cd05848    22 VILNCEARGNPVPTYRWLRNGTEidTESDYRYSLI-DGNLIISNPSEVkDSGRYQCLATNSIGS 84

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: 37.81 E-value: 2.96e-03

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 2024455041 321 VQIGSTVDFECKPKASPKARCSWKKGGEQLHENERITLLKDGG--LRITNVTKVDAGSYTCVATNQFGTASGTTNLVV 396
Cdd:cd04978    11 LSPGETGELICEAEGNPQPTITWRLNGVPIEPAPEDMRRTVDGrtLIFSNLQPNDTAVYQCNASNVHGYLLANAFLHV 88

Immunoglobulin (Ig)-like domain of vascular endothelial growth factor (VEGF) receptor (R) and similar proteins; member of the I-set of IgSF domains; The members here are composed of the immunoglobulin (Ig)-like domain of vascular endothelial growth factor (VEGF) receptor (R) and related proteins. 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). VEGF-A interacts with both VEGFR-1 and VEGFR-2. VEGFR-1 binds strongest to VEGF; VEGF-2 binds more weakly. VEGFR-3 appears not to bind VEGF, but binds other members of the VEGF family (VEGF-C and -D). VEGFRs bind VEGFs with high affinity with 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 also contains alpha-type platelet-derived growth factor receptor precursor (PDGFR)-alpha (CD140a), and PDGFR-beta (CD140b). PDGFRs alpha and beta have an extracellular component with five Ig-like domains, a transmembrane segment, and a cytoplasmic portion that has protein tyrosine kinase activity.

Pssm-ID: 409404 Cd Length: 102 Bit Score: 37.90 E-value: 3.14e-03

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 407 SNMDVTVGESVILPCQVQHDPILDISFTWYFNGT--------LTDFKKDASHFEKVggsaSGDLMIRNIQLKHSGKYVCM 478
Cdd:cd05742    10 EPTVLPQGETLVLNCTANVNLNEVVDFQWTYPSEkegklallKPDIKVDWSEPGEF----VSTLTIPEATLKDSGTYTCA 85


                  ...
gi 2024455041 479 VKT 481
Cdd:cd05742    86 ARS 88

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: 38.21 E-value: 3.37e-03

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 317 KMIQVQIGSTVDFECKPKASPKA---RCSW----------------KKGGEQLHENERITLLK-----DGGLRITNVTKV 372
Cdd:pfam07686   4 REVTVALGGSVTLPCTYSSSMSEastSVYWyrqppgkgptfliayySNGSEEGVKKGRFSGRGdpsngDGSLTIQNLTLS 83

                          90       100
                  ....*....|....*....|....*.
gi 2024455041 373 DAGSYTC-VATNQFGTASGTTNLVVT 397
Cdd:pfam07686  84 DSGTYTCaVIPSGEGVFGKGTRLTVL 109

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: 37.79 E-value: 3.41e-03

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 321 VQIGSTVDFECKPKASPKARCSWKK-----GGEQLHENE-RITLLKDGG---------LRITNVTKVDAGSYTCVATNQF 385
Cdd:cd04974    13 VVLGSDVEFHCKVYSDAQPHIQWLKhvevnGSKYGPDGLpYVTVLKVAGvnttgeentLTISNVTFDDAGEYICLAGNSI 92


                  .
gi 2024455041 386 G 386
Cdd:cd04974    93 G 93

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: 37.53 E-value: 3.87e-03

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 308 PDFSKNPM--KKMIQVQIGSTVDFECKPKASPKARCSWKKGGEQL-----HENERitllKDGGLRITNVTKVDAGSYTCV 380
Cdd:cd05856     1 PRFTQPAKmrRRVIARPVGSSVRLKCVASGNPRPDITWLKDNKPLtppeiGENKK----KKWTLSLKNLKPEDSGKYTCH 76

                          90
                  ....*....|.
gi 2024455041 381 ATNQFGTASGT 391
Cdd:cd05856    77 VSNRAGEINAT 87

Third immunoglobulin-like domain of the human WFIKKN (WAP, follistatin, immunoglobulin, Kunitz and NTR domain-containing protein), and similar domains; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the third immunoglobulin-like domain of the human WFIKKN (WAP, follistatin, immunoglobulin, Kunitz and NTR domain-containing protein) and similar proteins. WFIKKN is a secreted protein that consists of multiple types of protease inhibitory modules, including two tandem Kunitz-type protease inhibitor-domains. The Ig superfamily is a heterogenous group of proteins built on a common fold comprised of a sandwich of two beta sheets. Members of the Ig superfamily 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. 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: 409422 [Multi-domain] Cd Length: 95 Bit Score: 37.53 E-value: 3.96e-03

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 2024455041 142 GSTVKLECFALGNPVPQINWRRTdgMPFPSKIKLRKSN----------GMIEIPNFQQEDAGLYECITENSRG 204
Cdd:cd05765    15 GETASFHCDVTGRPQPEITWEKQ--VPGKENLIMRPNHvrgnvvvtniGQLVIYNAQPQDAGLYTCTARNSGG 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: 37.09 E-value: 4.68e-03

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 402 IILAPSNMDVTVGESVILPCQVQHDPILDISftWYFNGTLTDFKKdashfEKVGGSASGDLMIRNIQLKHSGKYVCMVKT 481
Cdd:cd20952     2 ILQGPQNQTVAVGGTVVLNCQATGEPVPTIS--WLKDGVPLLGKD-----ERITTLENGSLQIKGAEKSDTGEYTCVALN 74

                          90
                  ....*....|...
gi 2024455041 482 EVDSVASAADLIV 494
Cdd:cd20952    75 LSGEATWSAVLDV 87

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: 36.71 E-value: 4.78e-03

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 2024455041 324 GSTVDFECKPKASPKARCSWK-KGGEQLHENEritllkdggLRITNVTKVDAGSYTCVATNQFGTASGTTNLVVT 397
Cdd:cd20948    10 GENLNLSCHAASNPPAQYSWTiNGTFQTSSQE---------LFLPAITENNEGTYTCSAHNSLTGKNISLVLSVT 75

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: 37.00 E-value: 5.05e-03

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 406 PSNMDVTVGESVILPCQ--VQH-DPILdisfTWYFNGTLTDFkkDASHFEKVGGsasGDLMIRNIQLKHSGKYVCMVKTE 482
Cdd:cd05724     4 PSDTQVAVGEMAVLECSppRGHpEPTV----SWRKDGQPLNL--DNERVRIVDD---GNLLIAEARKSDEGTYKCVATNM 74

                          90
                  ....*....|...
gi 2024455041 483 V-DSVASAADLIV 494
Cdd:cd05724    75 VgERESRAARLSV 87

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: 37.06 E-value: 5.19e-03

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 322 QIGSTVDFECKPKASPKARCSWKKGGEQLHENER-ITLLKDGG---LRITNVT-KVDAGSYTCVATNQFGTASGTTNLVV 396
Cdd:cd20971    14 RYQSNATLVCKVTGHPKPIVKWYRQGKEIIADGLkYRIQEFKGgyhQLIIASVtDDDATVYQVRATNQGGSVSGTASLEV 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: 36.79 E-value: 5.24e-03

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 222 QMIKDTEIAVEDTLYWDCRAS-GKPKPSYRWLKNGEQL-----SVEGRIQIENGALTISSLNLTDSGRYQCIAENKHGVI 295
Cdd:pfam00047   1 SAPPTVTVLEGDSATLTCSAStGSPGPDVTWSKEGGTLieslkVKHDNGRTTQSSLLISNVTKEDAGTYTCVVNNPGGSA 80


                  ....*.
gi 2024455041 296 YSSAEL 301
Cdd:pfam00047  81 TLSTSL 86

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: 37.21 E-value: 5.60e-03

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 126 EPKIEVQFPETLPAAKgstVKLECFALGNPVPQINWRR--TDgMPFPSKIKLRKSNGMIEIPNFQQ-EDAGLYECITENS 202
Cdd:cd05850     7 EQPSSTLFPEGSAEEK---VTLACRARASPPATYRWKMngTE-LKMEPDSRYRLVAGNLVISNPVKaKDAGSYQCLASNR 82


                  ....*..
gi 2024455041 203 RGKNIAR 209
Cdd:cd05850    83 RGTVVSR 89

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: 36.72 E-value: 6.11e-03

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 2024455041 142 GSTVKLECFALGNpVPQINWRRTDGMPFPSKIKLRKSNGMIEIPNFQQEDAGLYECIT-ENSRGK 205
Cdd:cd05873    11 GGNAELKCSPKSN-LARVVWKFQGKVLKAESPKYGLYGDGLLIFNASEADAGRYQCLSvEKSKAK 74

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: 36.81 E-value: 6.47e-03

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 302 RVVASAPDfsknpmkkMIQVQIGSTVDFECKPKASPKARCSWKKGGEQLHENERITLLKDGG----LRITNVTKVDAGSY 377
Cdd:cd05891     2 KVIGGLPD--------VVTIMEGKTLNLTCTVFGNPDPEVIWFKNDQDIELSEHYSVKLEQGkyasLTIKGVTSEDSGKY 73


                  ....*....
gi 2024455041 378 TCVATNQFG 386
Cdd:cd05891    74 SINVKNKYG 82

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: 37.44 E-value: 6.63e-03

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 406 PSNMDVTVGESVILPCQVQHDPILDI-SFTWYF---------------NGTLTDFKKDASHFEKVGGSASGDLMIRNIQL 469
Cdd:pfam07686   3 PREVTVALGGSVTLPCTYSSSMSEAStSVYWYRqppgkgptfliayysNGSEEGVKKGRFSGRGDPSNGDGSLTIQNLTL 82

                          90
                  ....*....|
gi 2024455041 470 KHSGKYVCMV 479
Cdd:pfam07686  83 SDSGTYTCAV 92

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: 36.72 E-value: 6.94e-03

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|..
gi 2024455041 251 WLKNGEQLSVEG-RIQIENGALTISSLNLTDSGRYQCIAENK 291
Cdd:cd05873    29 WKFQGKVLKAESpKYGLYGDGLLIFNASEADAGRYQCLSVEK 70

First immunoglobulin variable (IgV) domain of poliovirus receptor (PVR, also known as CD155 and necl-5), and similar domains; The members here are composed of the first immunoglobulin (Ig) domain of poliovirus receptor (PVR, also known as CD155 and nectin-like protein 5 (necl-5)). Poliovirus (PV) binds to its cellular receptor (PVR/CD155) to initiate infection. CD155 is a membrane-anchored, single-span glycoprotein; its extracellular region has three Ig-like domains. There are four different isotypes of CD155 (referred to as alpha, beta, gamma, and delta), that result from alternate splicing of the CD155 mRNA, and have identical extracellular domains. CD155-beta and CD155-gamma are secreted; CD155-alpha and CD155-delta are membrane-bound and function as PV receptors. The virus recognition site is contained in the amino-terminal domain, D1. Having the virus attachment site on the receptor distal from the plasma membrane may be important for successful initiation of infection of cells by the virus. CD155 binds in the poliovirus "canyon" with a footprint similar to that of the intercellular adhesion molecule-1 receptor on human rhinoviruses. This group also includes the first Ig-like domain of nectin-1 (also known as poliovirus receptor related protein(PVRL)1; CD111), nectin-3 (also known as PVRL 3), nectin-4 (also known as PVRL4; LNIR receptor)and DNAX accessory molecule 1 (DNAM-1; CD226).

Pssm-ID: 409383 Cd Length: 113 Bit Score: 37.04 E-value: 7.67e-03

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 129 IEVQFPETLPAAKGSTVKLECfALGNPVP----QINWRRTD--------------GMPFPSKIKLR---------KSNGM 181
Cdd:cd05718     1 QRVQVPTEVTGFLGGSVTLPC-SLTSPGTtkitQVTWMKIGagssqnvavfhpqyGPSVPNPYAERveflaarlgLRNAT 79

                          90
                  ....*....|....*.
gi 2024455041 182 IEIPNFQQEDAGLYEC 197
Cdd:cd05718    80 LRIRNLRVEDEGNYIC 95

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: 36.40 E-value: 8.39e-03

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041  27 KMRSTVSVREGQGVVLLCGTPPRAGELSFAWIFN----EYPSFVQEDSRRfVSQETghLYIAKVEPSDVGNYTCVVTSTV 102
Cdd:pfam00047   1 SAPPTVTVLEGDSATLTCSASTGSPGPDVTWSKEggtlIESLKVKHDNGR-TTQSS--LLISNVTKEDAGTYTCVVNNPG 77


                  ....
gi 2024455041 103 TNSQ 106
Cdd:pfam00047  78 GSAT 81

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: 36.86 E-value: 8.98e-03

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                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2024455041 320 QVQIGSTVDFECKPKASPKARCSWKKGGEQLHENERITLLK-DGG--LRITNVTKVDAGSYTCVATNQFGTASGTTNLVV 396
Cdd:cd05762    12 KVRAGESVELFCKVTGTQPITCTWMKFRKQIQEGEGIKIENtENSskLTITEGQQEHCGCYTLEVENKLGSRQAQVNLTV 91


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gi 2024455041 397 TE 398
Cdd:cd05762    92 VD 93