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B-lymphocyte antigen CD19 isoform 2 precursor [Mus musculus]
immunoglobulin domain-containing family protein( domain architecture ID 34076)
immunoglobulin (Ig) domain-containing family protein is a member of a large superfamily containing cell surface antigen receptors, co-receptors and co-stimulatory molecules of the immune system, molecules involved in antigen presentation to lymphocytes, cell adhesion molecules, certain cytokine receptors and intracellular muscle proteins; immunoglobulin domains are typically divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets
List of domain hits
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Name | Accession | Description | Interval | E-value | |||
CD19_protodomain_1_2 | cd23999 | CD19 (Cluster of Differentiation 19), a unique double immunoglobulin (Ig)-fold protodomain 1 ... |
24-115 | 1.01e-49 | |||
CD19 (Cluster of Differentiation 19), a unique double immunoglobulin (Ig)-fold protodomain 1 and 2; CD19, also known as B-Lymphocyte Surface Antigen B4, T-Cell Surface Antigen Leu-12, and CVID3, is a transmembrane receptor present on various types of B cells, including progenitor, naive, and memory B cells, as well as plasmablasts. Until recently, it was believed to comprise two extracellular immunoglobulin (Ig) structural domains arranged in tandem with C2 topology. However, recent crystal structures have shown that the CD19 extracellular domain contains a unique double Ig domain that is responsible for its binding to proteins such as CD21, CD81, and CD225, which regulate B cell activation and survival. A recent analysis of the CD19 extracellular domain sequence reveals two "Ig domains", but the structure demonstrates that these two domains are not folded independently and connected in tandem. Rather, they fold together as one intertwined domain that can be referred to as a "double Ig" domain. Each of the two regular Ig domain sequences has a noticeably short linker that forms a loop between strands C' and D, rather than allowing the formation of a C" strand. Additionally, the two Ig-domain sequences are separated by a long linker that is structured as a small insertion domain, enabling both Ig sequences to fold together as a unique double Ig-domain. The CD19 domain comprises four "protodomains": two formed by A'B-CC' strands and two by DE-FG strands that interdigitate to form a novel double Ig fold. When analyzing this double Ig domain in terms of the usual Ig-fold, A'B-CC' protodomain of the first Ig sequence combines with DE-FG protodomain of the second, and vice versa. Hence, the second combined Ig fold is inverted, with DE-FG protodomain of the first Ig sequence combining with A'B-CC' protodomain of the second Ig sequence and in that order, as if it were a circular permutation, obtained only through structural folding. This group contains the protodomains 1 and 2 of the CD19 double Ig domain. : Pssm-ID: 467826 Cd Length: 92 Bit Score: 166.06 E-value: 1.01e-49
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CD19_double_Ig super family | cl49627 | CD19 (Cluster of Differentiation 19), a unique double immunoglobulin (Ig)-fold domain; CD19, ... |
183-272 | 7.20e-43 | |||
CD19 (Cluster of Differentiation 19), a unique double immunoglobulin (Ig)-fold domain; CD19, also known as B-Lymphocyte Surface Antigen B4, T-Cell Surface Antigen Leu-12, and CVID3, is a transmembrane receptor present on various types of B cells, including progenitor, naive, and memory B cells, as well as plasmablasts. Until recently, it was believed to comprise two extracellular immunoglobulin (Ig) structural domains arranged in tandem with C2 topology. However, recent crystal structures have shown that the CD19 extracellular domain contains a unique double Ig domain that is responsible for its binding to proteins such as CD21, CD81, and CD225, which regulate B cell activation and survival. A recent analysis of the CD19 extracellular domain sequence reveals two "Ig domains", but the structure demonstrates that these two domains are not folded independently and connected in tandem. Rather, they fold together as one intertwined domain that can be referred to as a "double Ig" domain. Each of the two regular Ig domain sequences has a noticeably short linker that forms a loop between strands C' and D, rather than allowing the formation of a C" strand. Additionally, the two Ig-domain sequences are separated by a long linker that is structured as a small insertion domain, enabling both Ig sequences to fold together as a unique double Ig-domain. The CD19 domain comprises four "protodomains": two formed by A'B-CC' strands and two by DE-FG strands that interdigitate to form a novel double Ig fold. When analyzing this double Ig domain in terms of the usual Ig-fold, A'B-CC' protodomain of the first Ig sequence combines with DE-FG protodomain of the second, and vice versa. Hence, the second combined Ig fold is inverted, with DE-FG protodomain of the first Ig sequence combining with A'B-CC' protodomain of the second Ig sequence and in that order, as if it were a circular permutation, obtained only through structural folding. The actual alignment was detected with superfamily member cd23998: Pssm-ID: 483967 Cd Length: 95 Bit Score: 148.02 E-value: 7.20e-43
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Name | Accession | Description | Interval | E-value | |||
CD19_protodomain_1_2 | cd23999 | CD19 (Cluster of Differentiation 19), a unique double immunoglobulin (Ig)-fold protodomain 1 ... |
24-115 | 1.01e-49 | |||
CD19 (Cluster of Differentiation 19), a unique double immunoglobulin (Ig)-fold protodomain 1 and 2; CD19, also known as B-Lymphocyte Surface Antigen B4, T-Cell Surface Antigen Leu-12, and CVID3, is a transmembrane receptor present on various types of B cells, including progenitor, naive, and memory B cells, as well as plasmablasts. Until recently, it was believed to comprise two extracellular immunoglobulin (Ig) structural domains arranged in tandem with C2 topology. However, recent crystal structures have shown that the CD19 extracellular domain contains a unique double Ig domain that is responsible for its binding to proteins such as CD21, CD81, and CD225, which regulate B cell activation and survival. A recent analysis of the CD19 extracellular domain sequence reveals two "Ig domains", but the structure demonstrates that these two domains are not folded independently and connected in tandem. Rather, they fold together as one intertwined domain that can be referred to as a "double Ig" domain. Each of the two regular Ig domain sequences has a noticeably short linker that forms a loop between strands C' and D, rather than allowing the formation of a C" strand. Additionally, the two Ig-domain sequences are separated by a long linker that is structured as a small insertion domain, enabling both Ig sequences to fold together as a unique double Ig-domain. The CD19 domain comprises four "protodomains": two formed by A'B-CC' strands and two by DE-FG strands that interdigitate to form a novel double Ig fold. When analyzing this double Ig domain in terms of the usual Ig-fold, A'B-CC' protodomain of the first Ig sequence combines with DE-FG protodomain of the second, and vice versa. Hence, the second combined Ig fold is inverted, with DE-FG protodomain of the first Ig sequence combining with A'B-CC' protodomain of the second Ig sequence and in that order, as if it were a circular permutation, obtained only through structural folding. This group contains the protodomains 1 and 2 of the CD19 double Ig domain. Pssm-ID: 467826 Cd Length: 92 Bit Score: 166.06 E-value: 1.01e-49
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CD19_protodomain_3_4 | cd23998 | CD19 (Cluster of Differentiation 19), a unique double immunoglobulin (Ig)-fold protodomain 3 ... |
183-272 | 7.20e-43 | |||
CD19 (Cluster of Differentiation 19), a unique double immunoglobulin (Ig)-fold protodomain 3 and 4; CD19, also known as B-Lymphocyte Surface Antigen B4, T-Cell Surface Antigen Leu-12, and CVID3, is a transmembrane receptor present on various types of B cells, including progenitor, naive, and memory B cells, as well as plasmablasts. Until recently, it was believed to comprise two extracellular immunoglobulin (Ig) structural domains arranged in tandem with C2 topology. However, recent crystal structures have shown that the CD19 extracellular domain contains a unique double Ig domain that is responsible for its binding to proteins such as CD21, CD81, and CD225, which regulate B cell activation and survival. A recent analysis of the CD19 extracellular domain sequence reveals two "Ig domains", but the structure demonstrates that these two domains are not folded independently and connected in tandem. Rather, they fold together as one intertwined domain that can be referred to as a "double Ig" domain. Each of the two regular Ig domain sequences has a noticeably short linker that forms a loop between strands C' and D, rather than allowing the formation of a C" strand. Additionally, the two Ig-domain sequences are separated by a long linker that is structured as a small insertion domain, enabling both Ig sequences to fold together as a unique double Ig-domain. The CD19 domain comprises four "protodomains": two formed by A'B-CC' strands and two by DE-FG strands that interdigitate to form a novel double Ig fold. When analyzing this double Ig domain in terms of the usual Ig-fold, A'B-CC' protodomain of the first Ig sequence combines with DE-FG protodomain of the second, and vice versa. Hence, the second combined Ig fold is inverted, with DE-FG protodomain of the first Ig sequence combining with A'B-CC' protodomain of the second Ig sequence and in that order, as if it were a circular permutation, obtained only through structural folding. This group contains the protodomains 3 and 4 of the CD19 double Ig domain. Pssm-ID: 467825 Cd Length: 95 Bit Score: 148.02 E-value: 7.20e-43
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IG_like | smart00410 | Immunoglobulin like; IG domains that cannot be classified into one of IGv1, IGc1, IGc2, IG. |
26-115 | 1.61e-04 | |||
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: 40.57 E-value: 1.61e-04
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IG_like | smart00410 | Immunoglobulin like; IG domains that cannot be classified into one of IGv1, IGc1, IGc2, IG. |
183-263 | 5.96e-04 | |||
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: 39.03 E-value: 5.96e-04
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Ig_3 | pfam13927 | Immunoglobulin domain; This family contains immunoglobulin-like domains. |
26-98 | 1.33e-03 | |||
Immunoglobulin domain; This family contains immunoglobulin-like domains. Pssm-ID: 464046 [Multi-domain] Cd Length: 78 Bit Score: 37.55 E-value: 1.33e-03
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Ig_3 | pfam13927 | Immunoglobulin domain; This family contains immunoglobulin-like domains. |
182-259 | 5.47e-03 | |||
Immunoglobulin domain; This family contains immunoglobulin-like domains. Pssm-ID: 464046 [Multi-domain] Cd Length: 78 Bit Score: 36.00 E-value: 5.47e-03
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Name | Accession | Description | Interval | E-value | |||
CD19_protodomain_1_2 | cd23999 | CD19 (Cluster of Differentiation 19), a unique double immunoglobulin (Ig)-fold protodomain 1 ... |
24-115 | 1.01e-49 | |||
CD19 (Cluster of Differentiation 19), a unique double immunoglobulin (Ig)-fold protodomain 1 and 2; CD19, also known as B-Lymphocyte Surface Antigen B4, T-Cell Surface Antigen Leu-12, and CVID3, is a transmembrane receptor present on various types of B cells, including progenitor, naive, and memory B cells, as well as plasmablasts. Until recently, it was believed to comprise two extracellular immunoglobulin (Ig) structural domains arranged in tandem with C2 topology. However, recent crystal structures have shown that the CD19 extracellular domain contains a unique double Ig domain that is responsible for its binding to proteins such as CD21, CD81, and CD225, which regulate B cell activation and survival. A recent analysis of the CD19 extracellular domain sequence reveals two "Ig domains", but the structure demonstrates that these two domains are not folded independently and connected in tandem. Rather, they fold together as one intertwined domain that can be referred to as a "double Ig" domain. Each of the two regular Ig domain sequences has a noticeably short linker that forms a loop between strands C' and D, rather than allowing the formation of a C" strand. Additionally, the two Ig-domain sequences are separated by a long linker that is structured as a small insertion domain, enabling both Ig sequences to fold together as a unique double Ig-domain. The CD19 domain comprises four "protodomains": two formed by A'B-CC' strands and two by DE-FG strands that interdigitate to form a novel double Ig fold. When analyzing this double Ig domain in terms of the usual Ig-fold, A'B-CC' protodomain of the first Ig sequence combines with DE-FG protodomain of the second, and vice versa. Hence, the second combined Ig fold is inverted, with DE-FG protodomain of the first Ig sequence combining with A'B-CC' protodomain of the second Ig sequence and in that order, as if it were a circular permutation, obtained only through structural folding. This group contains the protodomains 1 and 2 of the CD19 double Ig domain. Pssm-ID: 467826 Cd Length: 92 Bit Score: 166.06 E-value: 1.01e-49
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CD19_protodomain_3_4 | cd23998 | CD19 (Cluster of Differentiation 19), a unique double immunoglobulin (Ig)-fold protodomain 3 ... |
183-272 | 7.20e-43 | |||
CD19 (Cluster of Differentiation 19), a unique double immunoglobulin (Ig)-fold protodomain 3 and 4; CD19, also known as B-Lymphocyte Surface Antigen B4, T-Cell Surface Antigen Leu-12, and CVID3, is a transmembrane receptor present on various types of B cells, including progenitor, naive, and memory B cells, as well as plasmablasts. Until recently, it was believed to comprise two extracellular immunoglobulin (Ig) structural domains arranged in tandem with C2 topology. However, recent crystal structures have shown that the CD19 extracellular domain contains a unique double Ig domain that is responsible for its binding to proteins such as CD21, CD81, and CD225, which regulate B cell activation and survival. A recent analysis of the CD19 extracellular domain sequence reveals two "Ig domains", but the structure demonstrates that these two domains are not folded independently and connected in tandem. Rather, they fold together as one intertwined domain that can be referred to as a "double Ig" domain. Each of the two regular Ig domain sequences has a noticeably short linker that forms a loop between strands C' and D, rather than allowing the formation of a C" strand. Additionally, the two Ig-domain sequences are separated by a long linker that is structured as a small insertion domain, enabling both Ig sequences to fold together as a unique double Ig-domain. The CD19 domain comprises four "protodomains": two formed by A'B-CC' strands and two by DE-FG strands that interdigitate to form a novel double Ig fold. When analyzing this double Ig domain in terms of the usual Ig-fold, A'B-CC' protodomain of the first Ig sequence combines with DE-FG protodomain of the second, and vice versa. Hence, the second combined Ig fold is inverted, with DE-FG protodomain of the first Ig sequence combining with A'B-CC' protodomain of the second Ig sequence and in that order, as if it were a circular permutation, obtained only through structural folding. This group contains the protodomains 3 and 4 of the CD19 double Ig domain. Pssm-ID: 467825 Cd Length: 95 Bit Score: 148.02 E-value: 7.20e-43
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CD19_double_Ig | cd23997 | CD19 (Cluster of Differentiation 19), a unique double immunoglobulin (Ig)-fold domain; CD19, ... |
24-115 | 2.18e-34 | |||
CD19 (Cluster of Differentiation 19), a unique double immunoglobulin (Ig)-fold domain; CD19, also known as B-Lymphocyte Surface Antigen B4, T-Cell Surface Antigen Leu-12, and CVID3, is a transmembrane receptor present on various types of B cells, including progenitor, naive, and memory B cells, as well as plasmablasts. Until recently, it was believed to comprise two extracellular immunoglobulin (Ig) structural domains arranged in tandem with C2 topology. However, recent crystal structures have shown that the CD19 extracellular domain contains a unique double Ig domain that is responsible for its binding to proteins such as CD21, CD81, and CD225, which regulate B cell activation and survival. A recent analysis of the CD19 extracellular domain sequence reveals two "Ig domains", but the structure demonstrates that these two domains are not folded independently and connected in tandem. Rather, they fold together as one intertwined domain that can be referred to as a "double Ig" domain. Each of the two regular Ig domain sequences has a noticeably short linker that forms a loop between strands C' and D, rather than allowing the formation of a C" strand. Additionally, the two Ig-domain sequences are separated by a long linker that is structured as a small insertion domain, enabling both Ig sequences to fold together as a unique double Ig-domain. The CD19 domain comprises four "protodomains": two formed by A'B-CC' strands and two by DE-FG strands that interdigitate to form a novel double Ig fold. When analyzing this double Ig domain in terms of the usual Ig-fold, A'B-CC' protodomain of the first Ig sequence combines with DE-FG protodomain of the second, and vice versa. Hence, the second combined Ig fold is inverted, with DE-FG protodomain of the first Ig sequence combining with A'B-CC' protodomain of the second Ig sequence and in that order, as if it were a circular permutation, obtained only through structural folding. Pssm-ID: 467824 Cd Length: 89 Bit Score: 124.76 E-value: 2.18e-34
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CD19_double_Ig | cd23997 | CD19 (Cluster of Differentiation 19), a unique double immunoglobulin (Ig)-fold domain; CD19, ... |
183-272 | 1.79e-22 | |||
CD19 (Cluster of Differentiation 19), a unique double immunoglobulin (Ig)-fold domain; CD19, also known as B-Lymphocyte Surface Antigen B4, T-Cell Surface Antigen Leu-12, and CVID3, is a transmembrane receptor present on various types of B cells, including progenitor, naive, and memory B cells, as well as plasmablasts. Until recently, it was believed to comprise two extracellular immunoglobulin (Ig) structural domains arranged in tandem with C2 topology. However, recent crystal structures have shown that the CD19 extracellular domain contains a unique double Ig domain that is responsible for its binding to proteins such as CD21, CD81, and CD225, which regulate B cell activation and survival. A recent analysis of the CD19 extracellular domain sequence reveals two "Ig domains", but the structure demonstrates that these two domains are not folded independently and connected in tandem. Rather, they fold together as one intertwined domain that can be referred to as a "double Ig" domain. Each of the two regular Ig domain sequences has a noticeably short linker that forms a loop between strands C' and D, rather than allowing the formation of a C" strand. Additionally, the two Ig-domain sequences are separated by a long linker that is structured as a small insertion domain, enabling both Ig sequences to fold together as a unique double Ig-domain. The CD19 domain comprises four "protodomains": two formed by A'B-CC' strands and two by DE-FG strands that interdigitate to form a novel double Ig fold. When analyzing this double Ig domain in terms of the usual Ig-fold, A'B-CC' protodomain of the first Ig sequence combines with DE-FG protodomain of the second, and vice versa. Hence, the second combined Ig fold is inverted, with DE-FG protodomain of the first Ig sequence combining with A'B-CC' protodomain of the second Ig sequence and in that order, as if it were a circular permutation, obtained only through structural folding. Pssm-ID: 467824 Cd Length: 89 Bit Score: 91.63 E-value: 1.79e-22
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Ig_Semaphorin_C | cd04979 | Immunoglobulin (Ig)-like domain at the C-terminus of semaphorins; The members here are ... |
185-267 | 4.39e-09 | |||
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: 53.62 E-value: 4.39e-09
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IgI_1_MuSK | cd20970 | agrin-responsive first immunoglobulin-like domains (Ig1) of the MuSK ectodomain; a member of ... |
20-97 | 1.27e-05 | |||
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: 44.04 E-value: 1.27e-05
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IG_like | smart00410 | Immunoglobulin like; IG domains that cannot be classified into one of IGv1, IGc1, IGc2, IG. |
26-115 | 1.61e-04 | |||
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: 40.57 E-value: 1.61e-04
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IG_like | smart00410 | Immunoglobulin like; IG domains that cannot be classified into one of IGv1, IGc1, IGc2, IG. |
183-263 | 5.96e-04 | |||
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: 39.03 E-value: 5.96e-04
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Ig_3 | pfam13927 | Immunoglobulin domain; This family contains immunoglobulin-like domains. |
26-98 | 1.33e-03 | |||
Immunoglobulin domain; This family contains immunoglobulin-like domains. Pssm-ID: 464046 [Multi-domain] Cd Length: 78 Bit Score: 37.55 E-value: 1.33e-03
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Ig_3 | pfam13927 | Immunoglobulin domain; This family contains immunoglobulin-like domains. |
182-259 | 5.47e-03 | |||
Immunoglobulin domain; This family contains immunoglobulin-like domains. Pssm-ID: 464046 [Multi-domain] Cd Length: 78 Bit Score: 36.00 E-value: 5.47e-03
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ig | pfam00047 | Immunoglobulin domain; Members of the immunoglobulin superfamily are found in hundreds of ... |
180-259 | 5.67e-03 | |||
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: 36.02 E-value: 5.67e-03
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