Src Homology 3 domain of Voltage-dependent L-type calcium channel subunit beta2; The beta2 subunit of voltage-dependent calcium channels (Ca(V)s) is one of four beta subunits present in vertebrates. It is expressed in the heart and is present in specific neuronal cells including cerebellar Purkinje cells, hippocampal pyramidal neurons, and photoreceptors. Knockout of the beta2 gene in mice results in embryonic lethality, demonstrating its importance in development. Ca(V)s are multi-protein complexes that regulate the entry of calcium into cells. They impact muscle contraction, neuronal migration, hormone and neurotransmitter release, and the activation of calcium-dependent signaling pathways. They are composed of four subunits: alpha1, alpha2delta, beta, and gamma. The beta subunit is a soluble and intracellular protein that interacts with the transmembrane alpha1 subunit. It facilitates the trafficking and proper localization of the alpha1 subunit to the cellular plasma membrane. Vertebrates contain four different beta subunits from distinct genes (beta1-4); each exists as multiple splice variants. All are expressed in the brain while other tissues show more specific expression patterns. The beta subunits show similarity to MAGUK (membrane-associated guanylate kinase) proteins in that they contain SH3 and inactive guanylate kinase (GuK) domains; however, they do not appear to contain a PDZ domain. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

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gi 269308235  84 TKPVAFAVRTNVSYSAAHEDDVPVPGMAISFEAKDFLHVKEKFNNDWWIGRLVKEGCEIGFIPSPVKLE 152
Cdd:cd12040    1 TKPVAFAVRTNVGYSAAHEDDVPVPGMAISFEAKDFLHVKEKFNNDWWIGRLVKEGCEIGFIPSPVKLE 69

Src Homology 3 domain of Voltage-dependent L-type calcium channel subunit beta2; The beta2 subunit of voltage-dependent calcium channels (Ca(V)s) is one of four beta subunits present in vertebrates. It is expressed in the heart and is present in specific neuronal cells including cerebellar Purkinje cells, hippocampal pyramidal neurons, and photoreceptors. Knockout of the beta2 gene in mice results in embryonic lethality, demonstrating its importance in development. Ca(V)s are multi-protein complexes that regulate the entry of calcium into cells. They impact muscle contraction, neuronal migration, hormone and neurotransmitter release, and the activation of calcium-dependent signaling pathways. They are composed of four subunits: alpha1, alpha2delta, beta, and gamma. The beta subunit is a soluble and intracellular protein that interacts with the transmembrane alpha1 subunit. It facilitates the trafficking and proper localization of the alpha1 subunit to the cellular plasma membrane. Vertebrates contain four different beta subunits from distinct genes (beta1-4); each exists as multiple splice variants. All are expressed in the brain while other tissues show more specific expression patterns. The beta subunits show similarity to MAGUK (membrane-associated guanylate kinase) proteins in that they contain SH3 and inactive guanylate kinase (GuK) domains; however, they do not appear to contain a PDZ domain. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

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gi 269308235  84 TKPVAFAVRTNVSYSAAHEDDVPVPGMAISFEAKDFLHVKEKFNNDWWIGRLVKEGCEIGFIPSPVKLE 152
Cdd:cd12040    1 TKPVAFAVRTNVGYSAAHEDDVPVPGMAISFEAKDFLHVKEKFNNDWWIGRLVKEGCEIGFIPSPVKLE 69

Voltage gated calcium channel subunit beta domain 4Aa N terminal; The beta subunit of voltage gated calcium channels is coded for by four genes 1-4. Gene 4 can produce two types of beta4A domain (beta4Aa and beta4Ab) according to how the gene splicing is carried out. This family is part of the beta4Aa N terminal domain. It is made up of an alpha helix and a beta strand. It is thought to regulate the channel properties through protein-protein interactions with non Ca channel proteins.

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gi 269308235   44 GSADSYTSRPSDSDVSLEEDREAVRREAERQAQAQLEKAKTK 85
Cdd:pfam12052   1 GSADSNTSRPSDSDLSLEEDREALRREAERQALAQLEKAKSK 42

SH3 domain; SH3 (Src homology 3) domains are often indicative of a protein involved in signal transduction related to cytoskeletal organization. First described in the Src cytoplasmic tyrosine kinase. The structure is a partly opened beta barrel.

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gi 269308235   97 YSAAHEDDvpvpgmaISFEAKDFLHVKEKFNNDWWIGRLVKEgcEIGFIPS 147
Cdd:pfam00018   6 YTAQEPDE-------LSFKKGDIIIVLEKSEDGWWKGRNKGG--KEGLIPS 47

Src Homology 3 domain of Voltage-dependent L-type calcium channel subunit beta2; The beta2 subunit of voltage-dependent calcium channels (Ca(V)s) is one of four beta subunits present in vertebrates. It is expressed in the heart and is present in specific neuronal cells including cerebellar Purkinje cells, hippocampal pyramidal neurons, and photoreceptors. Knockout of the beta2 gene in mice results in embryonic lethality, demonstrating its importance in development. Ca(V)s are multi-protein complexes that regulate the entry of calcium into cells. They impact muscle contraction, neuronal migration, hormone and neurotransmitter release, and the activation of calcium-dependent signaling pathways. They are composed of four subunits: alpha1, alpha2delta, beta, and gamma. The beta subunit is a soluble and intracellular protein that interacts with the transmembrane alpha1 subunit. It facilitates the trafficking and proper localization of the alpha1 subunit to the cellular plasma membrane. Vertebrates contain four different beta subunits from distinct genes (beta1-4); each exists as multiple splice variants. All are expressed in the brain while other tissues show more specific expression patterns. The beta subunits show similarity to MAGUK (membrane-associated guanylate kinase) proteins in that they contain SH3 and inactive guanylate kinase (GuK) domains; however, they do not appear to contain a PDZ domain. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

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gi 269308235  84 TKPVAFAVRTNVSYSAAHEDDVPVPGMAISFEAKDFLHVKEKFNNDWWIGRLVKEGCEIGFIPSPVKLE 152
Cdd:cd12040    1 TKPVAFAVRTNVGYSAAHEDDVPVPGMAISFEAKDFLHVKEKFNNDWWIGRLVKEGCEIGFIPSPVKLE 69

Src Homology 3 domain of Voltage-dependent L-type calcium channel subunit beta4; The beta4 subunit of voltage-dependent calcium channels (Ca(V)s) is one of four beta subunits present in vertebrates. It is the only beta subunit expressed in the cochlea and is highly expressed in the brain, predominantly in the cerebellum. Ca(V)s are multi-protein complexes that regulate the entry of calcium into cells. They impact muscle contraction, neuronal migration, hormone and neurotransmitter release, and the activation of calcium-dependent signaling pathways. They are composed of four subunits: alpha1, alpha2delta, beta, and gamma. The beta subunit is a soluble and intracellular protein that interacts with the transmembrane alpha1 subunit. It facilitates the trafficking and proper localization of the alpha1 subunit to the cellular plasma membrane. Vertebrates contain four different beta subunits from distinct genes (beta1-4); each exists as multiple splice variants. All are expressed in the brain while other tissues show more specific expression patterns. The beta subunits show similarity to MAGUK (membrane-associated guanylate kinase) proteins in that they contain SH3 and inactive guanylate kinase (GuK) domains; however, they do not appear to contain a PDZ domain. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

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gi 269308235  85 KPVAFAVRTNVSYSAAHEDDVPVPGMAISFEAKDFLHVKEKFNNDWWIGRLVKEGCEIGFIPSPVKLE 152
Cdd:cd12043    1 KPVAFAVRTNVSYCGALDEDVPVPGTAISFDAKDFLHIKEKYNNDWWIGRLVKEGCEIGFIPSPLRLE 68

Src Homology 3 domain of Voltage-dependent L-type calcium channel subunit beta3; The beta3 subunit of voltage-dependent calcium channels (Ca(V)s) is one of four beta subunits present in vertebrates. It is the main beta subunit present in smooth muscles and is strongly expressed in the brain; it is predominant in the olfactory bulb, cortex, and hippocampus. It may play a role in regulating the NMDAR (N-methyl-d-aspartate receptor) activity in the hippocampus and thus, activity-dependent synaptic plasticity and cognitive behaviors. Ca(V)s are multi-protein complexes that regulate the entry of calcium into cells. They impact muscle contraction, neuronal migration, hormone and neurotransmitter release, and the activation of calcium-dependent signaling pathways. They are composed of four subunits: alpha1, alpha2delta, beta, and gamma. The beta subunit is a soluble and intracellular protein that interacts with the transmembrane alpha1 subunit. It facilitates the trafficking and proper localization of the alpha1 subunit to the cellular plasma membrane. Vertebrates contain four different beta subunits from distinct genes (beta1-4); each exists as multiple splice variants. All are expressed in the brain while other tissues show more specific expression patterns. The beta subunits show similarity to MAGUK (membrane-associated guanylate kinase) proteins in that they contain SH3 and inactive guanylate kinase (GuK) domains; however, they do not appear to contain a PDZ domain. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

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gi 269308235  85 KPVAFAVRTNVSYSAAHEDDVPVPGMAISFEAKDFLHVKEKFNNDWWIGRLVKEGCEIGFIPSPVKLE 152
Cdd:cd12042    1 KPVAFAVRTNVSYCGALDEECPVQGAAINFEAKDFLHIKEKYSNDWWIGRLVKEGGDIAFIPSPQRLE 68

Voltage gated calcium channel subunit beta domain 4Aa N terminal; The beta subunit of voltage gated calcium channels is coded for by four genes 1-4. Gene 4 can produce two types of beta4A domain (beta4Aa and beta4Ab) according to how the gene splicing is carried out. This family is part of the beta4Aa N terminal domain. It is made up of an alpha helix and a beta strand. It is thought to regulate the channel properties through protein-protein interactions with non Ca channel proteins.

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gi 269308235   44 GSADSYTSRPSDSDVSLEEDREAVRREAERQAQAQLEKAKTK 85
Cdd:pfam12052   1 GSADSNTSRPSDSDLSLEEDREALRREAERQALAQLEKAKSK 42

Src Homology 3 domain superfamily; Src Homology 3 (SH3) domains are protein interaction domains that bind proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. Thus, they are referred to as proline-recognition domains (PRDs). SH3 domains are less selective and show more diverse specificity compared to other PRDs. They have been shown to bind peptide sequences that lack the PxxP motif; examples include the PxxDY motif of Eps8 and the RKxxYxxY sequence in SKAP55. SH3 domain containing proteins play versatile and diverse roles in the cell, including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies, among others. Many members of this superfamily are adaptor proteins that associate with a number of protein partners, facilitating complex formation and signal transduction.

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gi 269308235  91 VRTNVSYSAAHEDDvpvpgmaISFEAKDFLHVKEKFNNDWWIGRLvkEGCEIGFIPS 147
Cdd:cd00174    2 ARALYDYEAQDDDE-------LSFKKGDIITVLEKDDDGWWEGEL--NGGREGLFPA 49

Src homology 3 domain of Src kinase-like Protein Tyrosine Kinases; Src subfamily members include Src, Lck, Hck, Blk, Lyn, Fgr, Fyn, Yrk, Yes, and Brk. Src (or c-Src) proteins are cytoplasmic (or non-receptor) PTKs which are anchored to the plasma membrane. They contain an N-terminal SH4 domain with a myristoylation site, followed by SH3 and SH2 domains, a tyr kinase domain, and a regulatory C-terminal region containing a conserved tyr. They are activated by autophosphorylation at the tyr kinase domain, but are negatively regulated by phosphorylation at the C-terminal tyr by Csk (C-terminal Src Kinase). However, Brk lacks the N-terminal myristoylation sites. Src proteins are involved in signaling pathways that regulate cytokine and growth factor responses, cytoskeleton dynamics, cell proliferation, survival, and differentiation. They were identified as the first proto-oncogene products, and they regulate cell adhesion, invasion, and motility in cancer cells, and tumor vasculature, contributing to cancer progression and metastasis. Src kinases are overexpressed in a variety of human cancers, making them attractive targets for therapy. They are also implicated in acute inflammatory responses and osteoclast function. Src, Fyn, Yes, and Yrk are widely expressed, while Blk, Lck, Hck, Fgr, Lyn, and Brk show a limited expression pattern. This subfamily also includes Drosophila Src42A, Src oncogene at 42A (also known as Dsrc41) which accumulates at sites of cell-cell or cell-matrix adhesion, and participates in Drosphila development and wound healing. It has been shown to promote tube elongation in the tracheal system, is essential for proper cell-cell matching during dorsal closure, and regulates cell-cell contacts in developing Drosophila eyes. The SH3 domain of Src kinases contributes to substrate recruitment by binding adaptor proteins/substrates, and regulation of kinase activity through an intramolecular interaction. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

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gi 269308235  96 SYSAAHEDDvpvpgmaISFEAKDFLHVKEKFNNDWWIGRLVKEGCEiGFIPS 147
Cdd:cd11845    7 DYEARTDDD-------LSFKKGDRLQILDDSDGDWWLARHLSTGKE-GYIPS 50

Src Homology 3 domain of Disks Large homolog 4; DLG4, also called postsynaptic density-95 (PSD95) or synapse-associated protein 90 (SAP90), is a scaffolding protein that clusters at synapses and plays an important role in synaptic development and plasticity. It is responsible for the membrane clustering and retention of many transporters and receptors such as potassium channels and PMCA4b, a P-type ion transport ATPase, among others. DLG4 is a member of the MAGUK (membrane-associated guanylate kinase) protein family, which is characterized by the presence of a core of three domains: PDZ, SH3, and guanylate kinase (GuK). The GuK domain in MAGUK proteins is enzymatically inactive; instead, the domain mediates protein-protein interactions and associates intramolecularly with the SH3 domain. DLG4 contains three PDZ domains. The SH3 domain of DLG4 binds and clusters the kainate subgroup of glutamate receptors via two proline-rich sequences in their C-terminal tail. It also binds AKAP79/150 (A-kinase anchoring protein). SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

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gi 269308235 104 DVPVPGMAISFEAKDFLHVKEKFNNDWWIGRLV---KEGCEIGFIPSPVKLE 152
Cdd:cd12030   15 DCGFLSQALSFRFGDVLHVIDAGDEEWWQARRVhsdSETEEIGFIPSKRRVE 66

Src Homology 3 domain of Membrane Protein, Palmitoylated 1 (or MAGUK p55 subfamily member 1); MPP1, also called 55 kDa erythrocyte membrane protein (p55), is a ubiquitously-expressed scaffolding protein that plays roles in regulating neutrophil polarity, cell shape, hair cell development, and neural development and patterning of the retina. It was originally identified as an erythrocyte protein that stabilizes the actin cytoskeleton to the plasma membrane by forming a complex with 4.1R protein and glycophorin C. MPP1 is one of seven vertebrate homologs of the Drosophila Stardust protein, which is required in establishing cell polarity, and it contains the three domains characteristic of MAGUK (membrane-associated guanylate kinase) proteins: PDZ, SH3, and guanylate kinase (GuK). In addition, it also contains the Hook (Protein 4.1 Binding) motif in between the SH3 and GuK domains. The GuK domain in MAGUK proteins is enzymatically inactive; instead, the domain mediates protein-protein interactions and associates intramolecularly with the SH3 domain. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

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gi 269308235  91 VRTNVSYSAAHEDDVPVPGMAISFEAKDFLHVKEKFNNDWWIGRLVKEGCE-IGFIPSP 148
Cdd:cd12080    2 MRAQFDYDPKKDNLIPCKEAGLKFQTGDIIQIINKDDSNWWQGRVEGSGEEsAGLIPSP 60

Src Homology 3 domain of metazoan osteoclast stimulating factor 1; OSTF1, also named OSF or SH3P2, is a signaling protein containing SH3 and ankyrin-repeat domains. It acts through a Src-related pathway to enhance the formation of osteoclasts and bone resorption. It also acts as a negative regulator of cell motility. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

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gi 269308235  91 VRTNVSYSAAHEDDvpvpgmaISFEAKDFLHVKEKFNNDWWIGRLvkEGCEiGFIPS 147
Cdd:cd11772    2 FRALYDYEAQHPDE-------LSFEEGDLLYISDKSDPNWWKATC--GGKT-GLIPS 48

Src Homology 3 domain of Disks Large homolog 3; DLG3, also called synapse-associated protein 102 (SAP102), is a scaffolding protein that clusters at synapses and plays an important role in synaptic development and plasticity. Mutations in DLG3 cause midgestational embryonic lethality in mice and may be associated with nonsyndromic X-linked mental retardation in humans. It interacts with the NEDD4 (neural precursor cell-expressed developmentally downregulated 4) family of ubiquitin ligases and promotes apical tight junction formation. DLG3 is a member of the MAGUK (membrane-associated guanylate kinase) protein family, which is characterized by the presence of a core of three domains: PDZ, SH3, and guanylate kinase (GuK). The GuK domain in MAGUK proteins is enzymatically inactive; instead, the domain mediates protein-protein interactions and associates intramolecularly with the SH3 domain. DLG3 contains three PDZ domains. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

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gi 269308235 104 DVPVPGMAISFEAKDFLHVKEKFNNDWWIGRLVK---EGCEIGFIPSPVKLE 152
Cdd:cd12029   16 DSCLPSQGLSFSYGDILHVINASDDEWWQARLVTphgESEQIGVIPSKKRVE 67

Src Homology 3 domain of Membrane Protein, Palmitoylated 2 (or MAGUK p55 subfamily member 2); MPP2 is a scaffolding protein that interacts with the non-receptor tyrosine kinase c-Src in epithelial cells to negatively regulate its activity and morphological function. It is one of seven vertebrate homologs of the Drosophila Stardust protein, which is required in establishing cell polarity, and it contains two L27 domains followed by the core of three domains characteristic of MAGUK (membrane-associated guanylate kinase) proteins: PDZ, SH3, and guanylate kinase (GuK). In addition, it also contains the Hook (Protein 4.1 Binding) motif in between the SH3 and GuK domains. The GuK domain in MAGUK proteins is enzymatically inactive; instead, the domain mediates protein-protein interactions and associates intramolecularly with the SH3 domain. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

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gi 269308235  91 VRTNVSYSAAHEDDVPVPGMAISFEAKDFLHVKEKFNNDWWIGRLVkEGCEIGFIPS 147
Cdd:cd12037    2 VKCHFDYDPSSDSLIPCKEAGLKFRAGDLLQIVNQEDPNWWQACHV-EGGSAGLIPS 57