CH1 domain (first constant Ig domain of the heavy chain) in immunoglobulin heavy epsilon and gamma chain; member of the C1-set of Ig superfamily (IgSF) domains; The members here are composed of the first immunoglobulin constant-1 set domain of epsilon and gamma chains. It belongs to a family composed of the first immunoglobulin constant-1 set domain of alpha, delta, epsilon, gamma, and mu heavy chains. This domain is found on the Fab antigen-binding fragment. The basic structure of Ig molecules is a tetramer of two light chains and two heavy chains linked by disulfide bonds. There are two types of light chains: kappa and lambda; each is composed of a constant domain and a variable domain. There are five types of heavy chains: alpha, delta, epsilon, gamma, and mu, all consisting of a variable domain (VH) with three (alpha, delta and gamma) or four (epsilon and mu) constant domains (CH1 to CH4). Ig molecules are modular proteins, in which the variable and constant domains have clear, conserved sequence patterns. This group belongs to the C1-set of IgSF domains, which are classical Ig-like domains resembling the antibody constant domain. C1-set domains are found almost exclusively in molecules involved in the immune system, such as in immunoglobulin light and heavy chains, in the major histocompatibility complex (MHC) class I and II complex molecules, and in various T-cell receptors.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
5GGR_A      118 GPSVFPLAPSSKSTSGGTAALGCLVKDYFPEPVTVSWNSGALTSGVHTFPAVLQSSGLYSLSSVVTVPSSSLGTQTYICN 197
Cdd:cd21817   1 APSVFPLAPCCKSTNGSSVTLGCLVTGYFPEPVTVTWNSGSLTSGVKTFPAVLQSSGLYTTSSQVTVPSSSWGSQTFTCN 80

                        90
                ....*....|....
5GGR_A      198 VNHKPSNTKVDKKV 211
Cdd:cd21817  81 VEHKPSSTKVDKKI 94

CH1 domain (first constant Ig domain of the heavy chain) in immunoglobulin heavy epsilon and gamma chain; member of the C1-set of Ig superfamily (IgSF) domains; The members here are composed of the first immunoglobulin constant-1 set domain of epsilon and gamma chains. It belongs to a family composed of the first immunoglobulin constant-1 set domain of alpha, delta, epsilon, gamma, and mu heavy chains. This domain is found on the Fab antigen-binding fragment. The basic structure of Ig molecules is a tetramer of two light chains and two heavy chains linked by disulfide bonds. There are two types of light chains: kappa and lambda; each is composed of a constant domain and a variable domain. There are five types of heavy chains: alpha, delta, epsilon, gamma, and mu, all consisting of a variable domain (VH) with three (alpha, delta and gamma) or four (epsilon and mu) constant domains (CH1 to CH4). Ig molecules are modular proteins, in which the variable and constant domains have clear, conserved sequence patterns. This group belongs to the C1-set of IgSF domains, which are classical Ig-like domains resembling the antibody constant domain. C1-set domains are found almost exclusively in molecules involved in the immune system, such as in immunoglobulin light and heavy chains, in the major histocompatibility complex (MHC) class I and II complex molecules, and in various T-cell receptors.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
5GGR_A      118 GPSVFPLAPSSKSTSGGTAALGCLVKDYFPEPVTVSWNSGALTSGVHTFPAVLQSSGLYSLSSVVTVPSSSLGTQTYICN 197
Cdd:cd21817   1 APSVFPLAPCCKSTNGSSVTLGCLVTGYFPEPVTVTWNSGSLTSGVKTFPAVLQSSGLYTTSSQVTVPSSSWGSQTFTCN 80

                        90
                ....*....|....
5GGR_A      198 VNHKPSNTKVDKKV 211
Cdd:cd21817  81 VEHKPSSTKVDKKI 94

Immunoglobulin C1-set domain;

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
5GGR_A        121 VFPLAPSSKSTsGGTAALGCLVKDYFPEPVTVSW--NSGALTSGVHTFPAVLQSSGLYSLSSV-VTVPSSSLGTQTYICN 197
Cdd:pfam07654   1 VYVFPPSPEEL-GKPNTLTCLVTGFYPPDITVTWlkNGQEVTEGVKTTPPSPNSDWTYQLSSYlTVTPSDWESGDEYTCR 79

                  ....
5GGR_A        198 VNHK 201
Cdd:pfam07654  80 VEHE 83

Immunoglobulin C-Type;

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....
5GGR_A         135 TAALGCLVKDYFPEPVTVSW--NSGALTSGVHTFPAVLQSSGLYSLSSVVTVPSSSLGT-QTYICNVNH 200
Cdd:smart00407   1 KATLVCLVSGFYPPDITVTWlrNGQEVTEGVSTTDPLKNSDGTYFLSSYLTVPASTWESgDVYTCQVTH 69

CH1 domain (first constant Ig domain of the heavy chain) in immunoglobulin heavy epsilon and gamma chain; member of the C1-set of Ig superfamily (IgSF) domains; The members here are composed of the first immunoglobulin constant-1 set domain of epsilon and gamma chains. It belongs to a family composed of the first immunoglobulin constant-1 set domain of alpha, delta, epsilon, gamma, and mu heavy chains. This domain is found on the Fab antigen-binding fragment. The basic structure of Ig molecules is a tetramer of two light chains and two heavy chains linked by disulfide bonds. There are two types of light chains: kappa and lambda; each is composed of a constant domain and a variable domain. There are five types of heavy chains: alpha, delta, epsilon, gamma, and mu, all consisting of a variable domain (VH) with three (alpha, delta and gamma) or four (epsilon and mu) constant domains (CH1 to CH4). Ig molecules are modular proteins, in which the variable and constant domains have clear, conserved sequence patterns. This group belongs to the C1-set of IgSF domains, which are classical Ig-like domains resembling the antibody constant domain. C1-set domains are found almost exclusively in molecules involved in the immune system, such as in immunoglobulin light and heavy chains, in the major histocompatibility complex (MHC) class I and II complex molecules, and in various T-cell receptors.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
5GGR_A      118 GPSVFPLAPSSKSTSGGTAALGCLVKDYFPEPVTVSWNSGALTSGVHTFPAVLQSSGLYSLSSVVTVPSSSLGTQTYICN 197
Cdd:cd21817   1 APSVFPLAPCCKSTNGSSVTLGCLVTGYFPEPVTVTWNSGSLTSGVKTFPAVLQSSGLYTTSSQVTVPSSSWGSQTFTCN 80

                        90
                ....*....|....
5GGR_A      198 VNHKPSNTKVDKKV 211
Cdd:cd21817  81 VEHKPSSTKVDKKI 94

CH1 domain (first constant Ig domain of the heavy chain) in immunoglobulin heavy alpha, delta, epsilon, gamma, and mu chains; member of the C1-set of Ig superfamily (IgSF) domains; The members here are composed of the first immunoglobulin constant-1 set domain of alpha, delta, epsilon, gamma, and mu heavy chains. This domain is found on the Fab antigen-binding fragment. The basic structure of Ig molecules is a tetramer of two light chains and two heavy chains linked by disulfide bonds. There are two types of light chains: kappa and lambda; each is composed of a constant domain and a variable domain. There are five types of heavy chains: alpha, delta, epsilon, gamma, and mu, all consisting of a variable domain (VH) with three (alpha, delta and gamma) or four (epsilon and mu) constant domains (CH1 to CH4). Ig molecules are modular proteins, in which the variable and constant domains have clear, conserved sequence patterns. This group belongs to the C1-set of IgSF domains, which are classical Ig-like domains resembling the antibody constant domain. C1-set domains are found almost exclusively in molecules involved in the immune system, such as in immunoglobulin light and heavy chains, in the major histocompatibility complex (MHC) class I and II complex molecules, and in various T-cell receptors.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
5GGR_A      118 GPSVFPLAPSSKSTSGGTAALGCLVKDYFPEPVTVSW---NSGALTSGVHTFPAVLQSSGLYSLSSVVTV-PSSSLGTQT 193
Cdd:cd04985   1 APTVFPLQSATKSQSNGPVALGCLISDYFPESITVSWqknTNSITSGFTRTFPVVLRSGGDYSCSSQLTVpLQEWNSGEV 80

                        90
                ....*....|....*...
5GGR_A      194 YICNVNHKPSNTKVDKKV 211
Cdd:cd04985  81 YKCQVQHSASNSKQEKDV 98

Immunoglobulin (Ig) variable (V) domain of T-cell receptor (TCR) gamma chain; The members here are composed of the immunoglobulin (Ig) variable (V) domain of the gamma chain of gamma/delta T-cell receptors (TCRs). TCRs mediate antigen recognition by T lymphocytes, and are heterodimers consisting of alpha and beta chains or gamma and delta chains. Each chain contains a variable (V) and a constant (C) region. The majority of T cells contain alpha/beta TCRs, but a small subset contain gamma/delta TCRs. Alpha/beta TCRs recognize antigens as peptide fragments presented by major histocompatibility complex (MHC) molecules. Gamma/delta TCRs recognize intact protein antigens directly without antigen processing and recognize MHC independently of the bound peptide. Gamma/delta T cells can also be stimulated by non-peptide antigens such as small phosphate- or amine-containing compounds. The variable domain of gamma/delta TCRs is responsible for antigen recognition and is located at the N-terminus of the receptor. Members of this group contain the standard Ig superfamily V-set AGFCC'C"/DEB domain topology.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
5GGR_A       13 QPGRSLRLDCKASGITFSNSGMHWVRQAPGKGLEWVAVIWYDGSKRYYADSVKGRFTISRDNSKNTLFLQMNSLRAEDTA 92
Cdd:cd04982  11 EESKSVTISCKVSGIDFSTTYIHWYRQKPGQALERLLYVSSTSAVRKDSGKTKNKFEARKDVGKSTSTLTITNLEKEDSA 90

                        90       100
                ....*....|....*....|....*..
5GGR_A       93 VYYCAtnddYW--GQGTLVTVSSASTK 117
Cdd:cd04982  91 TYYCA----YWesGSGYYIKVFGSGTK 113

CH1 domain (first constant Ig domain of the heavy chain) in immunoglobulin heavy alpha chain; member of the C1-set of Ig superfamily (IgSF) domains; The members here are composed of the first immunoglobulin constant-1 set domain of alpha chains. It belongs to a family composed of the first immunoglobulin constant-1 set domain of alpha, epsilon, gamma, and mu heavy chains. This domain is found on the Fab antigen-binding fragment. The basic structure of Ig molecules is a tetramer of two light chains and two heavy chains linked by disulfide bonds. There are two types of light chains: kappa and lambda; each is composed of a constant domain and a variable domain. There are five types of heavy chains: alpha, delta, epsilon, gamma, and mu, all consisting of a variable domain (VH) with three (alpha, delta and gamma) or four (epsilon and mu) constant domains (CH1 to CH4). Ig molecules are modular proteins, in which the variable and constant domains have clear, conserved sequence patterns. This group belongs to the C1-set of IgSF domains, which are classical Ig-like domains resembling the antibody constant domain. C1-set domains are found almost exclusively in molecules involved in the immune system, such as in immunoglobulin light and heavy chains, in the major histocompatibility complex (MHC) class I and II complex molecules, and in various T-cell receptors.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
5GGR_A      119 PSVFPLApSSKSTSGGTAALGCLVKDYFPEPVTVSWNSGALTSGVHTFPAVLQSSGLYSLSSVVTVPSSS-LGTQTYICN 197
Cdd:cd21818   2 PTVFPLS-LCPSLSSDPVVIGCLVQGFFPEPVNVTWNYSGKGGTARNFPAMLASGGRYTQSSQLTLPADQcPEGEAYKCS 80

                ...
5GGR_A      198 VNH 200
Cdd:cd21818  81 VQH 83

CH1 domain (first constant Ig domain of the heavy chain) in immunoglobulin heavy mu chain; member of the C1-set of Ig superfamily (IgSF) domains; The members here are composed of the first immunoglobulin constant-1 set domain of mu chains. It belongs to a family composed of the first immunoglobulin constant-1 set domain of alpha, delta, epsilon, gamma, and mu heavy chains. This domain is found on the Fab antigen-binding fragment. The basic structure of Ig molecules is a tetramer of two light chains and two heavy chains linked by disulfide bonds. There are two types of light chains: kappa and lambda; each is composed of a constant domain and a variable domain. There are five types of heavy chains: alpha, delta, epsilon, gamma, and mu, all consisting of a variable domain (VH) with three (alpha, delta and gamma) or four (epsilon and mu) constant domains (CH1 to CH4). Ig molecules are modular proteins, in which the variable and constant domains have clear, conserved sequence patterns. This group belongs to the C1-set of IgSF domains, which are classical Ig-like domains resembling the antibody constant domain. C1-set domains are found almost exclusively in molecules involved in the immune system, such as in immunoglobulin light and heavy chains, in the major histocompatibility complex (MHC) class I and II complex molecules, and in various T-cell receptors.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
5GGR_A      119 PSVFPLAPSSkSTSGGTAALGCLVKDYFPEPVTVSWNSG--ALTSGVHTFPAVLqSSGLYSLSSVVTVPSSSLGTQTYI- 195
Cdd:cd21819   2 PTLFPLVSCG-SSTSDPVTVGCLATDFLPDSITFSWTDDnnSLTTGVKTYPSVL-TGGTYTASSQLQVPESEWKSKENFy 79

                        90
                ....*....|....*...
5GGR_A      196 CNVNHkpSNTKVDKKVEP 213
Cdd:cd21819  80 CKVEH--PGGNKEVPVPK 95

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

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
5GGR_A           7 SGGGVVQPGRSLRLDCKASGitFSNSGMHWVRQapgkGLEWVAViwydgskryyadsvKGRFTISRDNskNTLFLQMNSL 86
Cdd:smart00410   1 PPSVTVKEGESVTLSCEASG--SPPPEVTWYKQ----GGKLLAE--------------SGRFSVSRSG--STSTLTISNV 58

                           90       100
                   ....*....|....*....|....*..
5GGR_A          87 RAEDTAVYYCATNDDYWG--QGTLVTV 111
Cdd:smart00410  59 TPEDSGTYTCAATNSSGSasSGTTLTV 85

Immunoglobulin (Ig) variable (V) domain of T-cell receptor (TCR) alpha chain and similar proteins; The members here are composed of the immunoglobulin (Ig) variable domain of the alpha chain of alpha/beta T-cell antigen receptors (TCRs). TCRs mediate antigen recognition by T lymphocytes, and are composed of alpha and beta, or gamma and delta polypeptide chains with variable (V) and constant (C) regions. This group represents the variable domain of the alpha chain of TCRs and also includes the variable domain of delta chains of TCRs. Alpha/beta TCRs recognize antigen as peptide fragments presented by major histocompatibility complex (MHC) molecules. The variable domain of TCRs is responsible for antigen recognition, and is located at the N-terminus of the receptor. Gamma/delta TCRs recognize intact protein antigens directly without antigen processing and recognize MHC independently of the bound peptide. Members of this group contain standard Ig superfamily V-set AGFCC'C"/DEB domain topology.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
5GGR_A       12 VQPGRSLRLDCKASGITFSNsgMHWVRQAPGKGLEWVAVIWYDGSKRYyadsvKGRFTISRDNSKNTLFLQMNSLRAEDT 91
Cdd:cd04983  10 VQEGENVTLNCNYSTSTFYY--LFWYRQYPGQGPQFLIYISSDSGNKK-----KGRFSATLDKSRKSSSLHISAAQLSDS 82

                        90       100
                ....*....|....*....|....*.
5GGR_A       92 AVYYCATNDDYW------GQGTLVTV 111
Cdd:cd04983  83 AVYFCALSESGGtgkltfGKGTRLTV 108

Immunoglobulin (Ig) lambda light chain variable (V) domain; The members here are composed of the immunoglobulin (Ig) light chain, lambda type, variable (V) domain. The basic structure of Ig molecules is a tetramer of two light chains and two heavy chains linked by disulfide bonds. There are two types of light chains: kappa and lambda, each composed of a constant domain (CL) and a variable domain (VL). There are five types of heavy chains (alpha, gamma, delta, epsilon, and mu), which determines the type of immunoglobulin formed: IgA, IgG, IgD, IgE, and IgM, respectively. In higher vertebrates, there are two types of light chain, designated kappa and lambda, which seem to be functionally identical, and can associate with any of the heavy chains. Members of this group contain standard Ig superfamily V-set AGFCC'C"/DEB domain topology.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
5GGR_A       12 VQPGRSLRLDCKASGITFSNSGMHWVRQAPGKGLewVAVIWYDGSKryyADSVKGRFTISrdNSKNTLFLQMNSLRAEDT 91
Cdd:cd04984  10 VSPGETVTITCTGSSGNISGNYVNWYQQKPGSAP--RYLIYEDKHR---PSGIPDRFSGS--KSGNTASLTISGAQTEDE 82

                        90       100
                ....*....|....*....|...
5GGR_A       92 AVYYCA---TNDDYWGQGTLVTV 111
Cdd:cd04984  83 ADYYCQvwdSNSYVFGGGTKLTV 105

Immunoglobulin (Ig) light chain, kappa type, variable (V) domain; The members here are composed of the immunoglobulin (Ig) light chain, kappa type, variable (V) domain. This group contains the standard Ig superfamily V-set AGFCC'C"/DEB domain topology. The basic structure of Ig molecules is a tetramer of two light chains and two heavy chains linked by disulfide bonds. There are two types of light chains: kappa and lambda, each composed of a constant domain (CL) and a variable domain (VL). There are five types of heavy chains (alpha, gamma, delta, epsilon, and mu), which determines the type of immunoglobulin formed: IgA, IgG, IgD, IgE, and IgM, respectively. In higher vertebrates, there are two types of light chain, designated kappa and lambda, which seem to be functionally identical, and can associate with any of the heavy chains.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
5GGR_A        2 VQLVESGGGV-VQPGRSLRLDCKASGITFSNSgMHWVRQAPGKGlewVAVIWYDGSKRyyADSVKGRFTISrdNSKNTLF 80
Cdd:cd04980   1 IVMTQSPASLsVSPGERVTISCKASQSISSNY-LAWYQQKPGQA---PKLLIYYASTL--HSGVPSRFSGS--GSGTDFT 72

                        90       100       110
                ....*....|....*....|....*....|
5GGR_A       81 LQMNSLRAEDTAVYYCATNDDY---WGQGT 107
Cdd:cd04980  73 LTISSVEPEDAAVYYCQQGYTFpytFGGGT 102

CH3 domain (third constant Ig domain of the heavy chain) in immunoglobulin heavy alpha, gamma, and delta chains, and CH4 domain (fourth constant Ig domain of the heavy chain) in immunoglobulin heavy alpha, epsilon, and mu chains; member of the C1-set of I; The members here are composed of the third and fourth immunoglobulin constant domain (IgC) of alpha, delta, gamma and alpha, epsilon, and mu heavy chains, respectively. This domain is found on the Fc fragment. The basic structure of Ig molecules is a tetramer of two light chains and two heavy chains linked by disulfide bonds. There are two types of light chains: kappa and lambda; each is composed of a constant domain and a variable domain. There are five types of heavy chains: alpha, delta, epsilon, gamma, and mu, all consisting of a variable domain (VH) with three (alpha, delta and gamma) or four (epsilon and mu) constant domains (CH1 to CH4). Ig molecules are modular proteins, in which the variable and constant domains have clear, conserved sequence patterns.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|
5GGR_A      119 PSVFPLAPSSKS-TSGGTAALGCLVKDYFPEPVTVSWNSG 157
Cdd:cd05768   1 PSVYLLPPPEEElSLNETVTLTCLVKGFYPEDIFVSWLQN 40

CH1 domain (first constant Ig domain of the heavy chain) in immunoglobulin delta chain; member of the C1-set of Ig superfamily (IgSF) domains; The members here are composed of the first immunoglobulin constant-1 set domain of delta chains. It belongs to a family composed of the first immunoglobulin constant-1 set domain of alpha, delta, epsilon, gamma, and mu heavy chains. This domain is found on the Fab antigen-binding fragment. The basic structure of Ig molecules is a tetramer of two light chains and two heavy chains linked by disulfide bonds. There are two types of light chains: kappa and lambda; each is composed of a constant domain and a variable domain. There are five types of heavy chains: alpha, delta, epsilon, gamma, and mu, all consisting of a variable domain (VH) with three (alpha, delta and gamma) or four (epsilon and mu) constant domains (CH1 to CH4). Ig molecules are modular proteins, in which the variable and constant domains have clear, conserved sequence patterns. This group belongs to the C1-set of IgSF domains, which are classical Ig-like domains resembling the antibody constant domain. C1-set domains are found almost exclusively in molecules involved in the immune system, such as in immunoglobulin light and heavy chains, in the major histocompatibility complex (MHC) class I and II complex molecules, and in various T-cell receptors.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
5GGR_A      118 GPSVFPLAPSSKSTSGGT-AALGCLVKDYFPEPVTVSWNSGALTSGVHTFPAVLQSSGLYSLSSVVTVPSSSLGTQTYIC 196
Cdd:cd16092   1 APDVFPIISGCRHPKDNSpVVLACLITGYHPTSVTVTWYMGTQSQPQRTFPEIQRRDSYYMTSSQLSTPLQQWRQGEYKC 80

                        90
                ....*....|
5GGR_A      197 NVNHKPSNTK 206
Cdd:cd16092  81 VVQHTASKSK 90

Gammadelta T-cell antigen receptor, variable (V) domain; The members here are composed of the immunoglobulin (Ig) variable (V) domain of the gamma/delta T-cell receptors (TCRs). TCRs mediate antigen recognition by T lymphocytes, and are heterodimers consisting of alpha and beta chains or gamma and delta chains. Each chain contains a variable (V) and a constant (C) region. The majority of T cells contain alpha/beta TCRs, but a small subset contain gamma/delta TCRs. Alpha/beta TCRs recognize antigen as peptide fragments presented by major histocompatibility complex (MHC) molecules. Gamma/delta TCRs recognize intact protein antigens; they recognize protein antigens directly and without antigen processing, and MHC independently of the bound peptide. Gamma/delta T cells can also be stimulated by non-peptide antigens such as small phosphate- or amine-containing compounds. The variable domain of gamma/delta TCRs is responsible for antigen recognition and is located at the N-terminus of the receptor. Members of this group contain standard Ig superfamily V-set AGFCC'C"/DEB domain topology.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
5GGR_A       12 VQPGRSLRLDCKASGITFSNSGMHWVRQAPGKGLEWvavIWYDGSKryYADSVKGRFTISRDNSKNTLFLQMNSLRAEDT 91
Cdd:cd20988  10 VSVGKPVTLKCSMKGEAISNYYINWYRKTQGNTMTF---IYREGGI--YGPGFKDNFRGDIDSSNNLAVLKILEASERDE 84

                        90       100
                ....*....|....*....|....*....
5GGR_A       92 AVYYCATNDD---------YWGQGTLVTV 111
Cdd:cd20988  85 GSYYCASDTPgggreydplIFGKGTYLTV 113

Immunoglobulin (Ig)-like variable (V) domain of Cluster of Differentiation (CD) 8 alpha chain; The members here are composed of the immunoglobulin (Ig)-like variable domain of the Cluster of Differentiation (CD) 8 alpha. The CD8 glycoprotein plays an essential role in the control of T-cell selection, maturation, and the T-cell receptor (TCR)-mediated response to peptide antigen. CD8 is comprised of alpha and beta subunits and is expressed as either an alpha/alpha or alpha/beta dimer. Both dimeric isoforms can serve as a coreceptor for T cell activation and differentiation, however they have distinct physiological roles, different cellular distributions, unique binding partners, etc. Each CD8 subunit is comprised of an extracellular domain containing a V-type Ig-like domain, a single pass transmembrane portion, and a short intracellular domain. The Ig domain of CD8 alpha binds to antibodies. Members of this group contain standard Ig superfamily V-set AGFCC'C"/DEB domain topology.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
5GGR_A       13 QPGRSLRLDCKASGItfSNSGMHWVRQAPGKGLEWVAVIWYDGSKRYYADSV--KGRFTISRDNskNTLFLQMNSLRAED 90
Cdd:cd05720  11 QLGQKVELVCEVLNS--VPQGCSWLFQPRGSAPQPTFLLYLSSSNKTKWAEGldSKRFSGSRSG--SSYVLTLKDFRKED 86

                ....*....
5GGR_A       91 TAVYYCATN 99
Cdd:cd05720  87 EGYYFCSVI 95