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.

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|.
gi 109458652 318 LRLRCMGWNPGSGKLSWSRDGRALETSDSEGTEPPRIRAErdqLLISRPVRSDHAQYTCHVRSPFGHTEAA 388
Cdd:cd00096    1 VTLTCSASGNPPPTITWYKNGKPLPPSSRDSRRSELGNGT---LTISNVTLEDSGTYTCVASNSAGGSASA 68

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.

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 109458652 223 VWRRGSKVLA-AGGLGSQAPLISLDPMNQARLRFDQIRGSLELTSARLDDAGVYTVEIIRGGVSQQI-REFVVGVY 296
Cdd:cd16842   27 TWSFKTSLAViAPGEGGAPEIIITDKSYKERLNISQNDYSLQISNLTMEDAGSYRARINTKNSRVTItKEFTLHIY 102

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.

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 109458652 411 SPALYVTAGSNVTLHCSAPSRPPADIAWSLADPTEAavpAGPRLLLPAVGPGHAGAYACIAANPRTGHRRRSVFNLTV 488
Cdd:cd20948    2 PSDTYYLSGENLNLSCHAASNPPAQYSWTINGTFQT---SSQELFLPAITENNEGTYTCSAHNSLTGKNISLVLSVTV 76

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.

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|.
gi 109458652 318 LRLRCMGWNPGSGKLSWSRDGRALETSDSEGTEPPRIRAErdqLLISRPVRSDHAQYTCHVRSPFGHTEAA 388
Cdd:cd00096    1 VTLTCSASGNPPPTITWYKNGKPLPPSSRDSRRSELGNGT---LTISNVTLEDSGTYTCVASNSAGGSASA 68

Immunoglobulin domain; This family contains immunoglobulin-like domains.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 109458652  300 PQLSVQPRAPETEEGAaELRLRCMGWNPGSGKLSWSRDGRALETSDsegTEPPRIRAERDQLLISRPVRSDHAQYTCHVR 379
Cdd:pfam13927   2 PVITVSPSSVTVREGE-TVTLTCEATGSPPPTITWYKNGEPISSGS---TRSRSLSGSNSTLTISNVTRSDAGTYTCVAS 77

N-terminal immunoglobulin (Ig)-like domain of the signaling lymphocyte activation molecule (SLAM) family; The members here are composed of the N-terminal immunoglobulin (Ig)-like domain of the signaling lymphocyte activation molecule (SLAM) family and similar proteins. The SLAM family is a group of immune-cell specific receptors that can regulate both adaptive and innate immune responses. Members of this group include proteins such as CD84, SLAM (CD150), Ly-9 (CD229), NTB-A (ly-108, SLAM6), 19A (CRACC), and SLAMF9. The genes coding for the SLAM family are nested on chromosome 1, in humans at 1q23, and in mice at 1H2. The SLAM family is a subset of the CD2 family, which also includes CD2 and CD58 located on chromosome 1 at 1p13 in humans. In mice, CD2 is located on chromosome 3, and there is no CD58 homolog. The SLAM family proteins are organized as an extracellular domain with either two or four Ig-like domains, a single transmembrane segment, and a cytoplasmic region having Tyr-based motifs. The extracellular domain is organized as a membrane-distal Ig variable (IgV) domain that is responsible for ligand recognition and a membrane-proximal truncated Ig constant-2 (IgC2) domain.

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 109458652 223 VWRRGSKVLA-AGGLGSQAPLISLDPMNQARLRFDQIRGSLELTSARLDDAGVYTVEIIRGGVSQQI-REFVVGVY 296
Cdd:cd16842   27 TWSFKTSLAViAPGEGGAPEIIITDKSYKERLNISQNDYSLQISNLTMEDAGSYRARINTKNSRVTItKEFTLHIY 102

Immunoglobulin domain; This family contains immunoglobulin-like domains.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 109458652  400 PVIRVSSDRdaspaLYVTAGSNVTLHCSAPSRPPADIAW--------SLADPTEAAVPAGPRLLLPAVGPGHAGAYACIA 471
Cdd:pfam13927   2 PVITVSPSS-----VTVREGETVTLTCEATGSPPPTITWykngepisSGSTRSRSLSGSNSTLTISNVTRSDAGTYTCVA 76

                  ..
gi 109458652  472 AN 473
Cdd:pfam13927  77 SN 78

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

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 109458652   411 SPALYVTAGSNVTLHCSAPSRPPADIAWSLADPTEaaVPAGPR-----------LLLPAVGPGHAGAYACIAANprTGHR 479
Cdd:smart00410   1 PPSVTVKEGESVTLSCEASGSPPPEVTWYKQGGKL--LAESGRfsvsrsgststLTISNVTPEDSGTYTCAATN--SSGS 76

                   ....*....
gi 109458652   480 RRSVFNLTV 488
Cdd:smart00410  77 ASSGTTLTV 85

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.

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 109458652 414 LYVTAGSNVTLHCSAPSRPPADIAWSLAD----PTEAAVPAGPRLLLPAVGPGHAGAYACIAANPR 475
Cdd:cd04968   11 TYALKGQTVTLECFALGNPVPQIKWRKVDgspsSQWEITTSEPVLEIPNVQFEDEGTYECEAENSR 76

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.

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|.
gi 109458652 318 LRLRCMGWNPGSGKLSWSRDGRALETSDSEGTEPPRIRAErdqLLISRPVRSDHAQYTCHVRSPFGHTEAA 388
Cdd:cd00096    1 VTLTCSASGNPPPTITWYKNGKPLPPSSRDSRRSELGNGT---LTISNVTLEDSGTYTCVASNSAGGSASA 68

Immunoglobulin domain; This family contains immunoglobulin-like domains.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 109458652  300 PQLSVQPRAPETEEGAaELRLRCMGWNPGSGKLSWSRDGRALETSDsegTEPPRIRAERDQLLISRPVRSDHAQYTCHVR 379
Cdd:pfam13927   2 PVITVSPSSVTVREGE-TVTLTCEATGSPPPTITWYKNGEPISSGS---TRSRSLSGSNSTLTISNVTRSDAGTYTCVAS 77

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).

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 109458652 300 PQLSVQPRAPETEEGAAElRLRCMGWNPGSG-KLSWSRDGRALETSDSEGTEppriRAERDQLLISRPVRSDHAQYTCHV 378
Cdd:cd20979    1 PVLKEQPAEVLFREGQPT-VLECVTEGGDQGvKYSWLKDGKSFNWQEHNVAQ----RKDEGSLVFLKPQASDEGQYQCFA 75

                 ....*
gi 109458652 379 RSPFG 383
Cdd:cd20979   76 ETPAG 80

N-terminal immunoglobulin (Ig)-like domain of the signaling lymphocyte activation molecule (SLAM) family; The members here are composed of the N-terminal immunoglobulin (Ig)-like domain of the signaling lymphocyte activation molecule (SLAM) family and similar proteins. The SLAM family is a group of immune-cell specific receptors that can regulate both adaptive and innate immune responses. Members of this group include proteins such as CD84, SLAM (CD150), Ly-9 (CD229), NTB-A (ly-108, SLAM6), 19A (CRACC), and SLAMF9. The genes coding for the SLAM family are nested on chromosome 1, in humans at 1q23, and in mice at 1H2. The SLAM family is a subset of the CD2 family, which also includes CD2 and CD58 located on chromosome 1 at 1p13 in humans. In mice, CD2 is located on chromosome 3, and there is no CD58 homolog. The SLAM family proteins are organized as an extracellular domain with either two or four Ig-like domains, a single transmembrane segment, and a cytoplasmic region having Tyr-based motifs. The extracellular domain is organized as a membrane-distal Ig variable (IgV) domain that is responsible for ligand recognition and a membrane-proximal truncated Ig constant-2 (IgC2) domain.

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 109458652 223 VWRRGSKVLA-AGGLGSQAPLISLDPMNQARLRFDQIRGSLELTSARLDDAGVYTVEIIRGGVSQQI-REFVVGVY 296
Cdd:cd16842   27 TWSFKTSLAViAPGEGGAPEIIITDKSYKERLNISQNDYSLQISNLTMEDAGSYRARINTKNSRVTItKEFTLHIY 102