Immunoglobulin Variable (IgV) domain at the N-terminus of CD33 and related Siglecs (sialic acid-binding Ig-like lectins); The members here are composed of the immunoglobulin (Ig) domain at the N-terminus of Cluster of Differentiation (CD) 33 and related Siglecs (sialic acid-binding Ig-like lectins). Siglec refers to a structurally related protein family that specifically recognizes sialic acid in oligosaccharide chains of glycoproteins and glycolipids. Siglecs are type I transmembrane proteins, organized as an extracellular module composed of Ig-like domains, an N-terminal variable set of Ig-like carbohydrate recognition domains, and 1 to 16 constant Ig-like domains, followed by transmembrane and short cytoplasmic domains. Human Siglecs are classified into two subgroups, one subgroup is comprised of sialoadhesin (Siglec-1), CD22 (Siglec-2), and MAG, the other subgroup is comprised of CD33-related Siglecs which include CD33 (Siglec-3) and human Siglecs 5-11.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 7657570   26 YSLTMQSSVTVQEGMCVHVRCSFSYPVDSQtDSDPVHGYWFRAGNDISWKAPVATNNPAWAVQEETRDRFHLLGDPQTKN 105
Cdd:cd05712   1 WGLQMPKSVTVQEGLCVLIPCSFSYPADYW-VSNPVHGYWYRGGPYPKYRPPVATNNRTREVHESTQGRFRLLGDPGKKN 79

                        90       100       110       120
                ....*....|....*....|....*....|....*....|
gi 7657570  106 CTLSIRDARMSDAGRYFFRMEKG-NIKWNYKYDQLSVNVT 144
Cdd:cd05712  80 CSLSISDARPEDSGKYFFRVERGdSNKYSYLSNQLSLTVT 119

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 7657570  261 SSSLSVLEGQSLRLVCAVDSNPPARLSWTWRSLTLYPSQpsnplVLEL-QVHLGDEGEFTCRAQNSLGSQHVSLNLSLQ 338
Cdd:cd20948   2 PSDTYYLSGENLNLSCHAASNPPAQYSWTINGTFQTSSQ-----ELFLpAITENNEGTYTCSAHNSLTGKNISLVLSVT 75

Immunoglobulin Variable (IgV) domain at the N-terminus of CD33 and related Siglecs (sialic acid-binding Ig-like lectins); The members here are composed of the immunoglobulin (Ig) domain at the N-terminus of Cluster of Differentiation (CD) 33 and related Siglecs (sialic acid-binding Ig-like lectins). Siglec refers to a structurally related protein family that specifically recognizes sialic acid in oligosaccharide chains of glycoproteins and glycolipids. Siglecs are type I transmembrane proteins, organized as an extracellular module composed of Ig-like domains, an N-terminal variable set of Ig-like carbohydrate recognition domains, and 1 to 16 constant Ig-like domains, followed by transmembrane and short cytoplasmic domains. Human Siglecs are classified into two subgroups, one subgroup is comprised of sialoadhesin (Siglec-1), CD22 (Siglec-2), and MAG, the other subgroup is comprised of CD33-related Siglecs which include CD33 (Siglec-3) and human Siglecs 5-11.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 7657570   26 YSLTMQSSVTVQEGMCVHVRCSFSYPVDSQtDSDPVHGYWFRAGNDISWKAPVATNNPAWAVQEETRDRFHLLGDPQTKN 105
Cdd:cd05712   1 WGLQMPKSVTVQEGLCVLIPCSFSYPADYW-VSNPVHGYWYRGGPYPKYRPPVATNNRTREVHESTQGRFRLLGDPGKKN 79

                        90       100       110       120
                ....*....|....*....|....*....|....*....|
gi 7657570  106 CTLSIRDARMSDAGRYFFRMEKG-NIKWNYKYDQLSVNVT 144
Cdd:cd05712  80 CSLSISDARPEDSGKYFFRVERGdSNKYSYLSNQLSLTVT 119

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 7657570  261 SSSLSVLEGQSLRLVCAVDSNPPARLSWTWRSLTLYPSQpsnplVLEL-QVHLGDEGEFTCRAQNSLGSQHVSLNLSLQ 338
Cdd:cd20948   2 PSDTYYLSGENLNLSCHAASNPPAQYSWTINGTFQTSSQ-----ELFLpAITENNEGTYTCSAHNSLTGKNISLVLSVT 75

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

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 7657570     29 TMQSSVTVQEGMCVHVRCSFSYPVDSQTDSdpVhgYWFR--AGNDISWKAPVATNNpawAVQEETRDRFHLLGDPQTKNC 106
Cdd:pfam07686   1 QTPREVTVALGGSVTLPCTYSSSMSEASTS--V--YWYRqpPGKGPTFLIAYYSNG---SEEGVKKGRFSGRGDPSNGDG 73

                          90
                  ....*....|....*....
gi 7657570    107 TLSIRDARMSDAGRYFFRM 125
Cdd:pfam07686  74 SLTIQNLTLSDSGTYTCAV 92

CD80-like C2-set immunoglobulin domain; These domains belong to the immunoglobulin superfamily.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 7657570    150 PNILIPGTLESGCFQN--LTCSVpwaCEQGTPPMISWMG-----------TSVSPLHPSTTRSSVLTLIPQPQHHGTSLT 216
Cdd:pfam08205   1 PTIEPPASLLEGEGPEvvATCSS---AGGKPAPRITWYLdgkpleaaetsSEQDPESGLVTVTSELKLVPSRSDHGQSLT 77

                  ....*..
gi 7657570    217 CQVTLPG 223
Cdd:pfam08205  78 CQVSYGA 84

Immunoglobulin Variable (IgV) domain at the N-terminus of CD33 and related Siglecs (sialic acid-binding Ig-like lectins); The members here are composed of the immunoglobulin (Ig) domain at the N-terminus of Cluster of Differentiation (CD) 33 and related Siglecs (sialic acid-binding Ig-like lectins). Siglec refers to a structurally related protein family that specifically recognizes sialic acid in oligosaccharide chains of glycoproteins and glycolipids. Siglecs are type I transmembrane proteins, organized as an extracellular module composed of Ig-like domains, an N-terminal variable set of Ig-like carbohydrate recognition domains, and 1 to 16 constant Ig-like domains, followed by transmembrane and short cytoplasmic domains. Human Siglecs are classified into two subgroups, one subgroup is comprised of sialoadhesin (Siglec-1), CD22 (Siglec-2), and MAG, the other subgroup is comprised of CD33-related Siglecs which include CD33 (Siglec-3) and human Siglecs 5-11.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 7657570   26 YSLTMQSSVTVQEGMCVHVRCSFSYPVDSQtDSDPVHGYWFRAGNDISWKAPVATNNPAWAVQEETRDRFHLLGDPQTKN 105
Cdd:cd05712   1 WGLQMPKSVTVQEGLCVLIPCSFSYPADYW-VSNPVHGYWYRGGPYPKYRPPVATNNRTREVHESTQGRFRLLGDPGKKN 79

                        90       100       110       120
                ....*....|....*....|....*....|....*....|
gi 7657570  106 CTLSIRDARMSDAGRYFFRMEKG-NIKWNYKYDQLSVNVT 144
Cdd:cd05712  80 CSLSISDARPEDSGKYFFRVERGdSNKYSYLSNQLSLTVT 119

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 7657570  261 SSSLSVLEGQSLRLVCAVDSNPPARLSWTWRSLTLYPSQpsnplVLEL-QVHLGDEGEFTCRAQNSLGSQHVSLNLSLQ 338
Cdd:cd20948   2 PSDTYYLSGENLNLSCHAASNPPAQYSWTINGTFQTSSQ-----ELFLpAITENNEGTYTCSAHNSLTGKNISLVLSVT 75

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

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 7657570     29 TMQSSVTVQEGMCVHVRCSFSYPVDSQTDSdpVhgYWFR--AGNDISWKAPVATNNpawAVQEETRDRFHLLGDPQTKNC 106
Cdd:pfam07686   1 QTPREVTVALGGSVTLPCTYSSSMSEASTS--V--YWYRqpPGKGPTFLIAYYSNG---SEEGVKKGRFSGRGDPSNGDG 73

                          90
                  ....*....|....*....
gi 7657570    107 TLSIRDARMSDAGRYFFRM 125
Cdd:pfam07686  74 SLTIQNLTLSDSGTYTCAV 92

Second immunoglobulin domain of Cluster of Differentiation (CD) 22; member of the Constant 1 (C1)-set of IgSF domains; The members here are composed of the second immunoglobulin domain of clusters of differentiation (CD) 22 (also known as Siglec-2). CD22, a sialic-acid binding immunoglobulin type-lectin (Siglec) family member, is an inhibitory co-receptor of the B-cell receptor (BCR). The inhibitory function of CD22 and its restricted expression on B cells makes CD22 an attractive target against dysregulated B cells that cause autoimmune diseases and B-cell-derived cancers. CD22 plays a vital role in establishing a baseline level of B-cell inhibition, and thus is an important determinant of homeostasis in humoral immunity. Siglecs are primarily expressed on immune cells and recognize sialic acid-containing glycan ligands. Siglecs are organized as an extracellular module composed of Ig-like domains (an N-terminal variable set of Ig-like carbohydrate recognition domains, and 1 to 16 constant Ig-like domains), followed by transmembrane and short cytoplasmic domains. Human Siglecs are classified into two subgroups, one subgroup is comprised of sialoadhesin (Siglec-1), CD22 (Siglec-2), and MAG (Siglec-4, myelin-associated glycoprotein), the other subgroup is comprised of CD33-related Siglecs which include CD33 (Siglec-3) and human Siglecs 5-11. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. This group belongs to the C1-set of IgSF domains.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 7657570  150 PNILIPGTLESGCFQNLTCSVPWACeQGTPPMISWM----------GTSVSPLHPSTTRSSVLTLIPQPQHHGTSLTCQV 219
Cdd:cd20938   3 PHIQLPPEIQESQEVTLTCLLNFSC-YGYPIQLQWLlegspmrqaaVTSTSLTIKSVFTRSELKFQPKWSHHGKIVTCQL 81

                        90
                ....*....|....*..
gi 7657570  220 TLPGAGVTTNRTIQLNV 236
Cdd:cd20938  82 QDADGKVLSEDTVQLNV 98

First immunoglobulin domain of Cluster of Differentiation (CD) 22; member of the V-set of IgSF domains; The members here are composed of the first immunoglobulin domain in Cluster of Differentiation (CD) 22 (also known as Siglec-2). CD22, a sialic-acid binding immunoglobulin type-lectin (Siglec) family member, is an inhibitory co-receptor of the B-cell receptor (BCR). The inhibitory function of CD22 and its restricted expression on B cells makes CD22 an attractive target against dysregulated B cells that cause autoimmune diseases and B-cell-derived cancers. CD22 plays a vital role in establishing a baseline level of B-cell inhibition, and thus is an important determinant of homeostasis in humoral immunity. Siglecs are primarily expressed on immune cells and recognize sialic acid-containing glycan ligands. Siglecs are organized as an extracellular module composed of Ig-like domains (an N-terminal variable set of Ig-like carbohydrate recognition domains, and 1 to 16 constant Ig-like domains), followed by transmembrane and short cytoplasmic domains. Human Siglecs are classified into two subgroups, one subgroup is comprised of sialoadhesin (Siglec-1), CD22 (Siglec-2), and MAG (Siglec-4, myelin-associated glycoprotein), the other subgroup is comprised of CD33-related Siglecs which include CD33 (Siglec-3) and human Siglecs 5-11. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. This group belongs to the V-set of IgSF domains.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 7657570   38 EGMCVHVRCSFSYPvDSQTDSDPV-HGYWFRAGNDiSWKAPVATNNPAWAVQEETRDRFHLLGDpQTKNCTLSIRDARMS 116
Cdd:cd20929  13 EGACVWIPCTYRAL-DGDLESFILfHNPEYNKATS-KFDGTRLYESTKDGKVPSEQKRVQFLGD-KNKNCTLSIHPVHLN 89

                        90
                ....*....|....*.
gi 7657570  117 DAGRYFFRMEKGNIKW 132
Cdd:cd20929  90 DSGQLGLRMESKTEKW 105

CD80-like C2-set immunoglobulin domain; These domains belong to the immunoglobulin superfamily.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 7657570    150 PNILIPGTLESGCFQN--LTCSVpwaCEQGTPPMISWMG-----------TSVSPLHPSTTRSSVLTLIPQPQHHGTSLT 216
Cdd:pfam08205   1 PTIEPPASLLEGEGPEvvATCSS---AGGKPAPRITWYLdgkpleaaetsSEQDPESGLVTVTSELKLVPSRSDHGQSLT 77

                  ....*..
gi 7657570    217 CQVTLPG 223
Cdd:pfam08205  78 CQVSYGA 84

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.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 7657570  261 SSSLSVLEGQSLRLVCAVDSNPPARLSWTWRSLTLYPS----QPSNPLVLELQVHLGDEGEFTCRAQNSLGS 328
Cdd:cd05876   2 SSSLVALRGQSLVLECIAEGLPTPTVKWLRPSGPLPPDrvkyQNHNKTLQLLNVGESDDGEYVCLAENSLGS 73

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
                ....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 7657570  272 LRLVCAVDSNPPARLSWTWRSLTLYPSQPSNPLVLE-------LQVHLGDEGEFTCRAQNSLGSQ 329
Cdd:cd00096   1 VTLTCSASGNPPPTITWYKNGKPLPPSSRDSRRSELgngtltiSNVTLEDSGTYTCVASNSAGGS 65

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.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 7657570  268 EGQSLRLVCAVDSNPPARLSWTWRSLTLypSQPSNPLVLE------LQVHLGDEGEFTCRAQNSLGSQHVSLNLSL 337
Cdd:cd05745   1 EGQTVDFLCEAQGYPQPVIAWTKGGSQL--SVDRRHLVLSsgtlriSRVALHDQGQYECQAVNIVGSQRTVAQLTV 74

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).

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 7657570   33 SVTVQEGMCVHVRCSFSYPVD---SQTDsdpvhgyWFRAGNDISwkAPVATNNPAW--AVQEETRDRFHLLGDPQT-KNC 106
Cdd:cd05718   8 EVTGFLGGSVTLPCSLTSPGTtkiTQVT-------WMKIGAGSS--QNVAVFHPQYgpSVPNPYAERVEFLAARLGlRNA 78

                        90
                ....*....|....*
gi 7657570  107 TLSIRDARMSDAGRY 121
Cdd:cd05718  79 TLRIRNLRVEDEGNY 93

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

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 7657570      31 QSSVTVQEGMCVHVRCSFSypvdsqtDSDPVHGYWFRagNDISWKAPvatnnpawavqeetRDRFHLlgDPQTKNCTLSI 110
Cdd:smart00410   1 PPSVTVKEGESVTLSCEAS-------GSPPPEVTWYK--QGGKLLAE--------------SGRFSV--SRSGSTSTLTI 55

                           90
                   ....*....|..
gi 7657570     111 RDARMSDAGRYF 122
Cdd:smart00410  56 SNVTPEDSGTYT 67

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.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 7657570  261 SSSLSVLEGQSLRLVCAVDSNPPARLSWTWRSLTLYPSQPS-----NPLVLElQVHLGDEGEFTCRAQNSLGSQH 330
Cdd:cd05731   2 ESSTMVLRGGVLLLECIAEGLPTPDIRWIKLGGELPKGRTKfenfnKTLKIE-NVSEADSGEYQCTASNTMGSAR 75

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.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 7657570  264 LSVLEGQSLRLVCAVDSNPPARLSW--TWRSLTLYPSQPS-NPLVLEL---QVHLGDEGEFTCRAQNSLG--SQHVSLNL 335
Cdd:cd20976  11 LEAVEGQDFVAQCSARGKPVPRITWirNAQPLQYAADRSTcEAGVGELhiqDVLPEDHGTYTCLAKNAAGqvSCSAWVTV 90