Second immunoglobulin (Ig)-like domain of Fcgamma-receptors (FcgammaRs), and similar domains; The members here are composed of the second 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.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 402478626  91 WLLLQAPRWVFKEEDPIHLRCHSWKNTALHKVTYLQNGKDRKYFHHNSDFHIPKATLKDSGSYFCRGLVGSKNVSSETVN 170
Cdd:cd05753    1 WLLLQAPSAVVFEGEPLTLRCHGWKDKKVHKVTYYKDGKALKFSYENSNFSIPQATLSDSGSYHCSGTVRIKRRSSESVN 80

                 ...
gi 402478626 171 ITI 173
Cdd:cd05753   81 ITV 83

Second immunoglobulin (Ig)-like domain of Fcgamma-receptors (FcgammaRs), and similar domains; The members here are composed of the second 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.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 402478626  91 WLLLQAPRWVFKEEDPIHLRCHSWKNTALHKVTYLQNGKDRKYFHHNSDFHIPKATLKDSGSYFCRGLVGSKNVSSETVN 170
Cdd:cd05753    1 WLLLQAPSAVVFEGEPLTLRCHGWKDKKVHKVTYYKDGKALKFSYENSNFSIPQATLSDSGSYHCSGTVRIKRRSSESVN 80

                 ...
gi 402478626 171 ITI 173
Cdd:cd05753   81 ITV 83

Immunoglobulin domain; This domain contains immunoglobulin-like domains.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 402478626   13 LEPQWYSVLEKDSVTLKCQgAYSPEDNSTQWFHNENLISSQaSSYFIDAATVNDSGEYRCQ---TNLSTLSDPVQLEV 87
Cdd:pfam13895   4 LTPSPTVVTEGEPVTLTCS-APGNPPPSYTWYKDGSAISSS-PNFFTLSVSAEDSGTYTCVarnGRGGKVSNPVELTV 79

Immunoglobulin domain; This domain contains immunoglobulin-like domains.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 402478626   91 WLLLQAPRWVFKEEDPIHLRCHSWKNtALHKVTYLQNGKDRKYfhhNSDFHIPKATLKDSGSYFCRGLVGSKNVSSETVN 170
Cdd:pfam13895   1 KPVLTPSPTVVTEGEPVTLTCSAPGN-PPPSYTWYKDGSAISS---SPNFFTLSVSAEDSGTYTCVARNGRGGKVSNPVE 76

                  ...
gi 402478626  171 ITI 173
Cdd:pfam13895  77 LTV 79

Second immunoglobulin (Ig)-like domain of Fcgamma-receptors (FcgammaRs), and similar domains; The members here are composed of the second 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.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 402478626  91 WLLLQAPRWVFKEEDPIHLRCHSWKNTALHKVTYLQNGKDRKYFHHNSDFHIPKATLKDSGSYFCRGLVGSKNVSSETVN 170
Cdd:cd05753    1 WLLLQAPSAVVFEGEPLTLRCHGWKDKKVHKVTYYKDGKALKFSYENSNFSIPQATLSDSGSYHCSGTVRIKRRSSESVN 80

                 ...
gi 402478626 171 ITI 173
Cdd:cd05753   81 ITV 83

Immunoglobulin domain; This domain contains immunoglobulin-like domains.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 402478626   13 LEPQWYSVLEKDSVTLKCQgAYSPEDNSTQWFHNENLISSQaSSYFIDAATVNDSGEYRCQ---TNLSTLSDPVQLEV 87
Cdd:pfam13895   4 LTPSPTVVTEGEPVTLTCS-APGNPPPSYTWYKDGSAISSS-PNFFTLSVSAEDSGTYTCVarnGRGGKVSNPVELTV 79

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

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 402478626    15 PQWYSVLEKDSVTLKCQGAYSPEDNSTqWFHNENLI-----------SSQASSYFIDAATVNDSGEYRCQTNLS--TLSD 81
Cdd:smart00410   1 PPSVTVKEGESVTLSCEASGSPPPEVT-WYKQGGKLlaesgrfsvsrSGSTSTLTISNVTPEDSGTYTCAATNSsgSASS 79

                   ....*.
gi 402478626    82 PVQLEV 87
Cdd:smart00410  80 GTTLTV 85

Immunoglobulin domain; This domain contains immunoglobulin-like domains.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 402478626   91 WLLLQAPRWVFKEEDPIHLRCHSWKNtALHKVTYLQNGKDRKYfhhNSDFHIPKATLKDSGSYFCRGLVGSKNVSSETVN 170
Cdd:pfam13895   1 KPVLTPSPTVVTEGEPVTLTCSAPGN-PPPSYTWYKDGSAISS---SPNFFTLSVSAEDSGTYTCVARNGRGGKVSNPVE 76

                  ...
gi 402478626  171 ITI 173
Cdd:pfam13895  77 LTV 79

First immunoglobulin (Ig)-like domain found in Leukocyte Ig-like receptors (LILRs), Natural killer inhibitory receptors (KIRs) and similar domains; member of Immunoglobulin Constant-2 set of IgSF domains; The members here are composed of the first immunoglobulin (Ig)-like domain found in Leukocyte Ig-like receptors (LILRs) and Natural killer inhibitory receptors (KIRs, also known as also known as cluster of differentiation (CD) 158), and similar proteins. This group includes LILRB1 (also known as LIR-1), LILRA5 (also known as LIR9), an activating natural cytotoxicity receptor NKp46, the immune-type receptor glycoprotein VI (GPVI), and the IgA-specific receptor Fc-alphaRI (also known as cluster of differentiation (CD) 89). LILRs are a family of immunoreceptors expressed on expressed on T and B cells, on monocytes, dendritic cells, and subgroups of natural killer (NK) cells. The human LILR family contains nine proteins (LILRA1-3, and 5, and LILRB1-5). From functional assays, and as the cytoplasmic domains of various LILRs, for example LILRB1, LILRB2 (also known as LIR-2), and LILRB3 (also known as LIR-3) contain immunoreceptor tyrosine-based inhibitory motifs (ITIMs), it is thought that LIR proteins are inhibitory receptors. Of the eight LIR family proteins, only LILRB1, and LILRB2, show detectable binding to class I MHC molecules; ligands for the other members have yet to be determined. The extracellular portions of the different LIR proteins contain different numbers of Ig-like domains for example, four in the case of LILRB1, and LILRB2, and two in the case of LILRB4 (also known as LIR-5). The activating natural cytotoxicity receptor NKp46 is expressed in natural killer cells, and is organized as an extracellular portion having two Ig-like extracellular domains, a transmembrane domain, and a small cytoplasmic portion. GPVI, which also contains two Ig-like domains, participates in the processes of collagen-mediated platelet activation and arterial thrombus formation. Fc-alphaRI is expressed on monocytes, eosinophils, neutrophils, and macrophages; it mediates IgA-induced immune effector responses such as phagocytosis, antibody-dependent cell-mediated cytotoxicity and respiratory burst. Killer cell immunoglobulin-like receptors (KIRs; also known as CD158 for human KIR) are transmembrane glycoproteins expressed by natural killer cells and subsets of T cells. KIRs are a family of highly polymorphic activating and inhibitory receptors that serve as key regulators of human NK cell function. The KIR proteins are classified by the number of extracellular immunoglobulin domains (2D or 3D) and by whether they have a long (L) or short (S) cytoplasmic domain. KIR proteins with the long cytoplasmic domain transduce inhibitory signals upon ligand binding via an immune tyrosine-based inhibitory motif (ITIM), while KIR proteins with the short cytoplasmic domain lack the ITIM motif and instead associate with the TYRO protein tyrosine kinase binding protein to transduce activating signals. The major ligands for KIR are MHC class I (HLA-A, -B or -C) molecules.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 402478626  19 SVLEKD-SVTLKCQGaySPEDNSTQWFHNENLISSQ-------ASSYFIDAATVNDSGEYRCQTNLSTL----SDPVQLE 86
Cdd:cd05751   10 SVIPLEkSVTIRCQG--TPEAFLYQLEKEGNSTETVipkkpqkKAEFIIPHMNSRTAGRYRCRYRKGAGwsepSDLLELV 87

                 .
gi 402478626  87 V 87
Cdd:cd05751   88 V 88

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.

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 402478626 109 LRCHSWKNTALHKVTYLQNGKD--RKYFHHN---------SDFHIPKATLKDSGSYFCRglVGSK-NVSSETVNITI 173
Cdd:cd05895   19 LRCETSSEYPSLRFKWFKNGKEinRKNKPENikiqkkkkkSELRINKASLADSGEYMCK--VSSKlGNDSASANVTI 93

Immunoglobulin I-set domain;

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 402478626    7 PKAVVFLEPQwySVLEKDSVTLKCQGAYSPeDNSTQWFHNENLISSQA----------SSYFIDAATVNDSGEYRCQ-TN 75
Cdd:pfam07679   1 PKFTQKPKDV--EVQEGESARFTCTVTGTP-DPEVSWFKDGQPLRSSDrfkvtyeggtYTLTISNVQPDDSGKYTCVaTN 77

Second immunoglobulin (Ig)-like domain found in Leukocyte Ig-like receptors, Natural killer inhibitory receptors (KIRs) and similar domains; member of Immunoglobulin Constant-2 set of IgSF domains; The members here are composed of the second immunoglobulin (Ig)-like domain found in Leukocyte Ig-like receptors (LILRs), Natural killer inhibitory receptors (KIRs, also known as also known as cluster of differentiation (CD) 158), and similar proteins. This group includes LILRB1 (also known as LIR-1), LILRA5 (also known as LIR9), an activating natural cytotoxicity receptor NKp46, the immune-type receptor glycoprotein VI (GPVI), and the IgA-specific receptor Fc-alphaRI (also known as cluster of differentiation (CD) 89). LILRs are a family of immunoreceptors expressed on expressed on T and B cells, on monocytes, dendritic cells, and subgroups of natural killer (NK) cells. The human LILR family contains nine proteins (LILRA1-3, and 5, and LILRB1-5). From functional assays, and as the cytoplasmic domains of various LILRs, for example LILRB1, LILRB2 (also known as LIR-2), and LILRB3 (also known as LIR-3) contain immunoreceptor tyrosine-based inhibitory motifs (ITIMs), it is thought that LIR proteins are inhibitory receptors. Of the eight LIR family proteins, only LILRB1, and LILRB2, show detectable binding to class I MHC molecules; ligands for the other members have yet to be determined. The extracellular portions of the different LIR proteins contain different numbers of Ig-like domains for example, four in the case of LILRB1, and LILRB2, and two in the case of LILRB4 (also known as LIR-5). The activating natural cytotoxicity receptor NKp46 is expressed in natural killer cells, and is organized as an extracellular portion having two Ig-like extracellular domains, a transmembrane domain, and a small cytoplasmic portion. GPVI, which also contains two Ig-like domains, participates in the processes of collagen-mediated platelet activation and arterial thrombus formation. Fc-alphaRI is expressed on monocytes, eosinophils, neutrophils, and macrophages; it mediates IgA-induced immune effector responses such as phagocytosis, antibody-dependent cell-mediated cytotoxicity and respiratory burst. Killer cell immunoglobulin-like receptors (KIRs; also known as CD158 for human KIR) are transmembrane glycoproteins expressed by natural killer cells and subsets of T cells. KIRs are a family of highly polymorphic activating and inhibitory receptors that serve as key regulators of human NK cell function. The KIR proteins are classified by the number of extracellular immunoglobulin domains (2D or 3D) and by whether they have a long (L) or short (S) cytoplasmic domain. KIR proteins with the long cytoplasmic domain transduce inhibitory signals upon ligand binding via an immune tyrosine-based inhibitory motif (ITIM), while KIR proteins with the short cytoplasmic domain lack the ITIM motif and instead associate with the TYRO protein tyrosine kinase binding protein to transduce activating signals. The major ligands for KIR are MHC class I (HLA-A, -B or -C) molecules.

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 402478626  26 VTLKCQGAYSPE--------DNSTQWFHnenLISSQASsYFIDAATVNDSGEYRC-------QTNLSTLSDPVQLEV 87
Cdd:cd05711   18 VTLQCHSRIGFDrfilykegRSPLLQFH---GSGFQAS-FPLGPVTPAHAGTYRCygsynhsPYEWSAPSDPLEIVV 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.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 402478626  97 PRWVFKEEDPIHLRCHSWKNTALhkVTYLQNGKD-------RKYFHHNSDFHIPKATLKDSGSYFCRglvgSKNVSSETV 169
Cdd:cd04979    4 KQISVKEGDTVILSCSVKSNNAP--VTWIHNGKKvpryrspRLVLKTERGLLIRSAQEADAGVYECH----SGERVLGST 77

                 ....*
gi 402478626 170 NITIT 174
Cdd:cd04979   78 LRSVT 82

Second immunoglobulin (Ig)-like domain of Fcgamma-receptors (FcgammaRs), and similar domains; The members here are composed of the second 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.

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 402478626  20 VLEKDSVTLKCQGAYSPEDNSTQWFHNENLI--SSQASSYFIDAATVNDSGEYRCQTNLSTL---SDPVQLEV 87
Cdd:cd05753   11 VFEGEPLTLRCHGWKDKKVHKVTYYKDGKALkfSYENSNFSIPQATLSDSGSYHCSGTVRIKrrsSESVNITV 83