Src homology 3 domain of JNK-interacting protein 2; JNK-interacting protein 2 (JIP2) is also called Mitogen-activated protein kinase 8-interacting protein 2 (MAPK8IP2) or Islet-brain-2 (IB2). It is widely expressed in the brain, where it forms complexes with fibroblast growth factor homologous factors (FHFs), which facilitates activation of the p38delta MAPK. JIP2 is enriched in postsynaptic densities and may play a role in motor and cognitive function. In addition to a JNK binding domain, JIP2 also contains SH3 and Phosphotyrosine-binding (PTB) domains. The SH3 domain of the related protein JIP1 homodimerizes at the interface usually involved in proline-rich ligand recognition, despite the lack of this motif in the domain itself. 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.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*
gi 20988692 614 THRAVFRFIPRHPDELELDVDDPVLVEAEEDDFWFRGFNMRTGERGVFPAFYAHA 668
Cdd:cd11942   1 THRAVFRFIPRHEDELELDVDDPLLVEAEEDDYWYRGYNMRTGERGIFPAFYAHE 55

Phosphotyrosine interaction domain (PTB/PID);

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20988692   689 FDVQFLGSVEVPCH-----------QGNGILCAAMQKIATARKLTVHLRPPASCDLEISLRGVKLSLsgggPEFQRCSHF 757
Cdd:pfam00640   1 FAVRYLGSVEVPEErapdkntrmqqAREAIRRVKAAKINKIRGLSGETGPGTKVDLFISTDGLKLLN----PDTQELIHD 76

                          90       100       110       120       130
                  ....*....|....*....|....*....|....*....|....*....|....*..
gi 20988692   758 FQMKNISFCGC-HPRNSCYFGFITKHPLLSRFACHVFVSQESMRPVARSVGRAFLEY 813
Cdd:pfam00640  77 HPLVSISFCADgDPDLMRYFAYIARDKATNKFACHVFESEDGAQDIAQSIGQAFALA 133

Src homology 3 domain of JNK-interacting protein 2; JNK-interacting protein 2 (JIP2) is also called Mitogen-activated protein kinase 8-interacting protein 2 (MAPK8IP2) or Islet-brain-2 (IB2). It is widely expressed in the brain, where it forms complexes with fibroblast growth factor homologous factors (FHFs), which facilitates activation of the p38delta MAPK. JIP2 is enriched in postsynaptic densities and may play a role in motor and cognitive function. In addition to a JNK binding domain, JIP2 also contains SH3 and Phosphotyrosine-binding (PTB) domains. The SH3 domain of the related protein JIP1 homodimerizes at the interface usually involved in proline-rich ligand recognition, despite the lack of this motif in the domain itself. 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.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*
gi 20988692 614 THRAVFRFIPRHPDELELDVDDPVLVEAEEDDFWFRGFNMRTGERGVFPAFYAHA 668
Cdd:cd11942   1 THRAVFRFIPRHEDELELDVDDPLLVEAEEDDYWYRGYNMRTGERGIFPAFYAHE 55

Src homology 3 domains; Src homology 3 (SH3) domains bind to target proteins through sequences containing proline and hydrophobic amino acids. Pro-containing polypeptides may bind to SH3 domains in 2 different binding orientations.

                           10        20        30        40        50
                   ....*....|....*....|....*....|....*....|....*....|....*
gi 20988692    611 REQTHRAVFRFIPRHPDELELDVDDPVLVEAEEDDFWFRGFNMRtGERGVFPAFY 665
Cdd:smart00326   1 EGPQVRALYDYTAQDPDELSFKKGDIITVLEKSDDGWWKGRLGR-GKEGLFPSNY 54

Phosphotyrosine interaction domain (PTB/PID);

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20988692   689 FDVQFLGSVEVPCH-----------QGNGILCAAMQKIATARKLTVHLRPPASCDLEISLRGVKLSLsgggPEFQRCSHF 757
Cdd:pfam00640   1 FAVRYLGSVEVPEErapdkntrmqqAREAIRRVKAAKINKIRGLSGETGPGTKVDLFISTDGLKLLN----PDTQELIHD 76

                          90       100       110       120       130
                  ....*....|....*....|....*....|....*....|....*....|....*..
gi 20988692   758 FQMKNISFCGC-HPRNSCYFGFITKHPLLSRFACHVFVSQESMRPVARSVGRAFLEY 813
Cdd:pfam00640  77 HPLVSISFCADgDPDLMRYFAYIARDKATNKFACHVFESEDGAQDIAQSIGQAFALA 133

Src homology 3 domain of JNK-interacting protein 2; JNK-interacting protein 2 (JIP2) is also called Mitogen-activated protein kinase 8-interacting protein 2 (MAPK8IP2) or Islet-brain-2 (IB2). It is widely expressed in the brain, where it forms complexes with fibroblast growth factor homologous factors (FHFs), which facilitates activation of the p38delta MAPK. JIP2 is enriched in postsynaptic densities and may play a role in motor and cognitive function. In addition to a JNK binding domain, JIP2 also contains SH3 and Phosphotyrosine-binding (PTB) domains. The SH3 domain of the related protein JIP1 homodimerizes at the interface usually involved in proline-rich ligand recognition, despite the lack of this motif in the domain itself. 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.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*
gi 20988692 614 THRAVFRFIPRHPDELELDVDDPVLVEAEEDDFWFRGFNMRTGERGVFPAFYAHA 668
Cdd:cd11942   1 THRAVFRFIPRHEDELELDVDDPLLVEAEEDDYWYRGYNMRTGERGIFPAFYAHE 55

Src homology 3 domain of JNK-interacting protein 1; JNK-interacting protein 1 (JIP1) is also called Islet-brain 1 (IB1) or Mitogen-activated protein kinase 8-interacting protein 1 (MAPK8IP1). It is highly expressed in neurons, where it functions as an adaptor linking motor to cargo during axonal transport. It also affects microtubule dynamics in neurons. JIP1 is also found in pancreatic beta-cells, where it is involved in regulating insulin secretion. In addition to a JNK binding domain, JIP1 also contains SH3 and Phosphotyrosine-binding (PTB) domains. Its SH3 domain homodimerizes at the interface usually involved in proline-rich ligand recognition, despite the lack of this motif in the domain itself. 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.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|...
gi 20988692 614 THRAVFRFIPRHPDELELDVDDPVLVEAEEDDFWFRGFNMRTGERGVFPAFYA 666
Cdd:cd11943   1 THRAVFRFVPRHPDELELEVDDPLLVEVQAEDYWYEAYNMRTGARGIFPAYYA 53

Src homology 3 domain of Ubiquitin-associated and SH3 domain-containing proteins, also called TULA (T cell Ubiquitin LigAnd) family of proteins; UBASH3 or TULA proteins are also referred to as Suppressor of T cell receptor Signaling (STS) proteins. They contain an N-terminal UBA domain, a central SH3 domain, and a C-terminal histidine phosphatase domain. They bind c-Cbl through the SH3 domain and to ubiquitin via UBA. In some vertebrates, there are two TULA family proteins, called UBASH3A (also called TULA or STS-2) and UBASH3B (also called TULA-2 or STS-1), which show partly overlapping as well as distinct functions. UBASH3B is widely expressed while UBASH3A is only found in lymphoid cells. UBASH3A facilitates apoptosis induced in T cells through its interaction with the apoptosis-inducing factor AIF. UBASH3B is an active phosphatase while UBASH3A is not. 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.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*.
gi 20988692 614 THRAVFRFIPRHPDELELDVDDPVLVEAEE----DDFWFRGFNMRTGERGVFPAFY 665
Cdd:cd11791   1 VLRVLYPYTPQEEDELELVPGDYIYVSPEEldssSDGWVEGTSWLTGCSGLLPENY 56

Variant SH3 domain;

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*....
gi 20988692   617 AVFRFIPRHPDELELDVDDPVLVEAEEDDFWFRGfnMRTGERGVFPAFY 665
Cdd:pfam14604   1 ALYPYEPKDDDELSLQRGDVITVIEESEDGWWEG--INTGRTGLVPANY 47

Adaptor protein containing PH domain, PTB domain, and Leucine zipper motif (APPL; also called DCC-interacting protein (DIP)-13alpha) Phosphotyrosine-binding (PTB) domain; APPL interacts with oncoprotein serine/threonine kinase AKT2, tumor suppressor protein DCC (deleted in colorectal cancer), Rab5, GIPC (GAIP-interacting protein, C terminus), human follicle-stimulating hormone receptor (FSHR), and the adiponectin receptors AdipoR1 and AdipoR2. There are two isoforms of human APPL: APPL1 and APPL2, which share about 50% sequence identity. APPL has a BAR and a PH domain near its N terminus, and the two domains are thought to function as a unit (BAR-PH domain). C-terminal to this is a PTB domain. Lipid binding assays show that the BAR, PH, and PTB domains can bind phospholipids. PTB domains have a common PH-like fold and are found in various eukaryotic signaling molecules. This domain was initially shown to binds peptides with a NPXY motif with differing requirements for phosphorylation of the tyrosine, although more recent studies have found that some types of PTB domains can bind to peptides lack tyrosine residues altogether. In contrast to SH2 domains, which recognize phosphotyrosine and adjacent carboxy-terminal residues, PTB-domain binding specificity is conferred by residues amino-terminal to the phosphotyrosine. PTB domains are classified into three groups: phosphotyrosine-dependent Shc-like, phosphotyrosine-dependent IRS-like, and phosphotyrosine-independent Dab-like PTB domains.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20988692 689 FDVQFLGSVEVPCHQGNGILCAAMQKIATAR------KLT-VHLRPPASCdleislrgvkLSLSggGPEFQRCSHFFQMK 761
Cdd:cd13158  13 FIVRFLGSMEVKSDRTSEVIYEAMRQVLAARaihnifRMTeSHLLVTSDC----------LRLI--DPQTQVTRARFPLA 80

                        90       100       110       120       130
                ....*....|....*....|....*....|....*....|....*....|..
gi 20988692 762 NISFCGCHPRNSCYFGFITKHP----LLSRFACHVFVSQESMRPVARSVGRA 809
Cdd:cd13158  81 DVVQFAAHQENKRLFGFVVRTPegdgEEPSFSCYVFESNTEGEKICDAIALA 132

Ankyrin repeat and sterile alpha motif (SAM) domain-containing (Anks) protein family Phosphotyrosine-binding (PTB) domain; Both AIDA-1b (AbetaPP intracellular domain-associated protein 1b) and Odin (also known as ankyrin repeat and sterile alpha motif domain-containing 1A; ANKS1A) belong to the Anks protein family. Both of these family members interacts with the EphA8 receptor. Ank members consists of ankyrin repeats, a SAM domain and a C-terminal PTB domain which is crucial for interaction with the juxtamembrane (JM) region of EphA8. PTB domains are classified into three groups, namely, phosphotyrosine-dependent Shc-like, phosphotyrosine-dependent IRS-like, and phosphotyrosine-independent Dab-like PTB domains of which the Anks PTB is a member. PTB domains have a common PH-like fold and are found in various eukaryotic signaling molecules. This domain was initially shown to binds peptides with a NPXY motif with differing requirements for phosphorylation of the tyrosine, although more recent studies have found that some types of PTB domains can bind to peptides lack tyrosine residues altogether. In contrast to SH2 domains, which recognize phosphotyrosine and adjacent carboxy-terminal residues, PTB-domain binding specificity is conferred by residues amino-terminal to the phosphotyrosine. PTB domains are classified into three groups: phosphotyrosine-dependent Shc-like, phosphotyrosine-dependent IRS-like, and phosphotyrosine-independent Dab-like PTB domains. This cd is part of the Dab-like subgroup.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20988692 688 RFDVQFLGSVEVPCHQGNGILCAAMQKIataRKLTVHLRPPASCDLEISLRGVKLSlsggGPEFQR--CSHffQMKNISf 765
Cdd:cd01274  16 NYEAHYLGSTEIKELRGTESTKKAIQKL---KKSTREMKKIPTIILSISYKGVKFI----DATTKNliCEH--EIRNIS- 85

                        90       100       110       120       130
                ....*....|....*....|....*....|....*....|....*....|...
gi 20988692 766 CGCH-PRNSCYFGFITKHPLLSRFACHVF--VSQESMRPVARSVGRAFLEYYQ 815
Cdd:cd01274  86 CACQdPEDLNTFAYITKDLKTDHHYCHVFcvLTVDLATEIILTLGQAFEVAYQ 138

Cell death protein 6 homolog (CED-6/GULP1) Phosphotyrosine-binding (PTB) domain; CED6 (also known as GULP1: engulfment adaptor PTB domain containing 1) is an adaptor protein involved in the specific recognition and engulfment of apoptotic cells. CED6 has been shown to interact with the cytoplasmic tail of another protein involved in the engulfment of apoptotic cells, CED1. CED6 has a C-terminal PTB domain, which can bind to NPXY motifs. PTB domains have a common PH-like fold and are found in various eukaryotic signaling molecules. This domain was initially shown to binds peptides with a NPXY motif with differing requirements for phosphorylation of the tyrosine, although more recent studies have found that some types of PTB domains can bind to peptides lack tyrosine residues altogether. In contrast to SH2 domains, which recognize phosphotyrosine and adjacent carboxy-terminal residues, PTB-domain binding specificity is conferred by residues amino-terminal to the phosphotyrosine. PTB domains are classified into three groups: phosphotyrosine-dependent Shc-like, phosphotyrosine-dependent IRS-like, and phosphotyrosine-independent Dab-like PTB domains. This cd is part of the Dab-like subgroup.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20988692 689 FDVQFLGSVEVPCHQGNGILCAAMQKIATARKLTVH--LRPPaSCDLEISLRGVKLSlsggGPEFQRCSHFFQMKNISFC 766
Cdd:cd01273  14 YLVKFLGCTEVEQPKGTEVVKEAIRKLKFARQLKKSegAKLP-KVELQISIDGVKIQ----DPKTKVIMHQFPLHRISFC 88

                        90       100       110       120       130
                ....*....|....*....|....*....|....*....|....*....|..
gi 20988692 767 GCHPRNSCYFGFITKHPLLSRFACHVFVSQESMRPVARSVGRAFLEYYQEHL 818
Cdd:cd01273  89 ADDKTDKRIFSFIAKDSESEKHLCFVFDSEKLAEEITLTIGQAFDLAYRRFL 140

Third Src Homology 3 domain of SH3 domain containing ring finger 1, an E3 ubiquitin-protein ligase; SH3RF1 is also called POSH (Plenty of SH3s) or SH3MD2 (SH3 multiple domains protein 2). It is a scaffold protein that acts as an E3 ubiquitin-protein ligase. It plays a role in calcium homeostasis through the control of the ubiquitin domain protein Herp. It may also have a role in regulating death receptor mediated and JNK mediated apoptosis. SH3RF1 also enhances the ubiquitination of ROMK1 potassium channel resulting in its increased endocytosis. It contains an N-terminal RING finger domain and four SH3 domains. This model represents the third SH3 domain, located in the middle, of SH3RF1. 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.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*....
gi 20988692 617 AVFRFIPRHPDELELDVDDPVLVEAEEDDFWFRGFNMRTGERGVFPAFY 665
Cdd:cd11926   4 AIYPYTPRKEDELELRKGEMFLVFERCQDGWFKGTSMHTSKIGVFPGNY 52

Third (or C-terminal) Src Homology 3 domain of Vinexin, also called Sorbin and SH3 domain containing 3 (Sorbs3); Vinexin is also called Sorbs3, SH3P3, and SH3-containing adapter molecule 1 (SCAM-1). It is an adaptor protein containing one sorbin homology (SoHo) and three SH3 domains. Vinexin was first identified as a vinculin binding protein; it is co-localized with vinculin at cell-ECM and cell-cell adhesion sites. There are several splice variants of vinexin: alpha, which contains the SoHo and three SH3 domains and displays tissue-specific expression; and beta, which contains only the three SH3 domains and is widely expressed. Vinexin alpha stimulates the accumulation of F-actin at focal contact sites. Vinexin also promotes keratinocyte migration and wound healing. The SH3 domains of vinexin have been reported to bind a number of ligands including vinculin, WAVE2, DLG5, Abl, and Cbl. 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.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*..
gi 20988692 613 QTHRAVFRFIPRHPDELELDVDDPVLVEAEEDDFWFRGFNMRTGERGVFPAFYAHAV 669
Cdd:cd11918   2 TPYKAVYQYRPQNEDELELREGDRVDVMQQCDDGWFVGVSRRTQKFGTFPGNYVAPV 58

Third (or C-terminal) Src Homology 3 domain of Sorbin and SH3 domain containing 1 (Sorbs1), also called ponsin; Sorbs1 is also called ponsin, SH3P12, or CAP (c-Cbl associated protein). It is an adaptor protein containing one sorbin homology (SoHo) and three SH3 domains. It binds Cbl and plays a major role in regulating the insulin signaling pathway by enhancing insulin-induced phosphorylation of Cbl. Sorbs1, like vinexin, localizes at cell-ECM and cell-cell adhesion sites where it binds vinculin, paxillin, and afadin. It may function in the control of cell motility. Other interaction partners of Sorbs1 include c-Abl, Sos, flotillin, Grb4, ataxin-7, filamin C, among others. 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.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|..
gi 20988692 614 THRAVFRFIPRHPDELELDVDDPVLVEAEEDDFWFRGFNMRTGERGVFPAFY 665
Cdd:cd11916   3 SYQALYSYAPQNDDELELRDGDIVDVMEKCDDGWFVGTSRRTKQFGTFPGNY 54

Src Homology 3 domain of Class A and B Dedicator of Cytokinesis proteins; DOCK proteins are atypical guanine nucleotide exchange factors (GEFs) that lack the conventional Dbl homology (DH) domain. They are divided into four classes (A-D) based on sequence similarity and domain architecture: class A includes Dock1, 2 and 5; class B includes Dock3 and 4; class C includes Dock6, 7, and 8; and class D includes Dock9, 10 and 11. All DOCKs contain two homology domains: the DHR-1 (Dock homology region-1), also called CZH1 (CED-5, Dock180, and MBC-zizimin homology 1), and DHR-2 (also called CZH2 or Docker). The DHR-1 domain binds phosphatidylinositol-3,4,5-triphosphate while DHR-2 contains the catalytic activity for Rac and/or Cdc42. This subfamily includes only Class A and B DOCKs, which also contain an SH3 domain at the N-terminal region and a PxxP motif at the C-terminus. Class A/B DOCKs are mostly specific GEFs for Rac, except Dock4 which activates the Ras family GTPase Rap1, probably indirectly through interaction with Rap regulatory proteins. The SH3 domain of class A/B DOCKs have been shown to bind Elmo, a scaffold protein that promotes GEF activity of DOCKs by releasing DHR-2 autoinhibition by the intramolecular 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.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|..
gi 20988692 617 AVFRFIPRHPDELELDVDDPVLVEaEEDDFWFRGFNMRT-GERGVFPAFYAH 667
Cdd:cd11872   4 AIYNFQGDGEHQLSLQVGDTVQIL-EECEGWYRGFSLRNkSLKGIFPKSYVH 54

Src homology 3 domain of Alpha1,6-fucosyltransferase (Fut8); Fut8 catalyzes the alpha1,6-linkage of a fucose residue from a donor substrate to N-linked oligosaccharides on glycoproteins in a process called core fucosylation, which is crucial for growth factor receptor-mediated biological functions. Fut8-deficient mice show severe growth retardation, early death, and a pulmonary emphysema-like phenotype. Fut8 is also implicated to play roles in aging and cancer metastasis. It contains an N-terminal coiled-coil domain, a catalytic domain, and a C-terminal SH3 domain. The SH3 domain of Fut8 is located in the lumen and its role in glycosyl transfer is unclear. 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.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|
gi 20988692 615 HRAVFRFIPRHPDELELDVDDPVLVEAEEDDFWFRGFNMRTGERGVFPAF 664
Cdd:cd11792   2 QVAIYPHKPRNHDEIELRVGDIIGVAGNHWDGYSKGRNRRTGKTGLYPSY 51

Src Homology 3 domain of Amphiphysin and related domains; Amphiphysins function primarily in endocytosis and other membrane remodeling events. They exist in several isoforms and mammals possess two amphiphysin proteins from distinct genes. Amphiphysin I proteins, enriched in the brain and nervous system, contain domains that bind clathrin, Adaptor Protein complex 2 (AP2), dynamin, and synaptojanin. They function in synaptic vesicle endocytosis. Human autoantibodies to amphiphysin I hinder GABAergic signaling and contribute to the pathogenesis of paraneoplastic stiff-person syndrome. Some amphiphysin II isoforms, also called Bridging integrator 1 (Bin1), are localized in many different tissues and may function in intracellular vesicle trafficking. In skeletal muscle, Bin1 plays a role in the organization and maintenance of the T-tubule network. Mutations in Bin1 are associated with autosomal recessive centronuclear myopathy. Amphiphysins contain an N-terminal BAR domain with an additional N-terminal amphipathic helix (an N-BAR), a variable central domain, and a C-terminal SH3 domain. The SH3 domain of amphiphysins bind proline-rich motifs present in binding partners such as dynamin, synaptojanin, and nsP3. It also belongs to a subset of SH3 domains that bind ubiquitin in a site that overlaps with the peptide binding site. 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.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|...
gi 20988692 616 RAVFRFIPRHPDELELDVDDPVLV-----EAEEDDFWFRGFNMRTGERGVFPA 663
Cdd:cd11790   6 RATHDYTAEDTDELTFEKGDVILVipfddPEEQDEGWLMGVKESTGCRGVFPE 58

Third Src Homology 3 domain of SH3 domain containing ring finger 3, an E3 ubiquitin-protein ligase; SH3RF3 is also called POSH2 (Plenty of SH3s 2) or SH3MD4 (SH3 multiple domains protein 4). It is a scaffold protein with E3 ubiquitin-protein ligase activity. It was identified in the screen for interacting partners of p21-activated kinase 2 (PAK2). It may play a role in regulating JNK mediated apoptosis in certain conditions. It also interacts with GTP-loaded Rac1. SH3RF3 is highly homologous to SH3RF1; it also contains an N-terminal RING finger domain and four SH3 domains. This model represents the third SH3 domain, located in the middle, of SH3RF3. 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.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|...
gi 20988692 617 AVFRFIPRHPDELELDVDDPVLVEAEEDDFWFRGFNMRTGERGVFPAFYAHAV 669
Cdd:cd11925   5 ALYAYKPQKNDELELRKGEMYRVIEKCQDGWFKGTSLRTGVSGVFPGNYVTPV 57

Src homology 3 domain of Ubiquitin-associated and SH3 domain-containing protein A; UBASH3A is also called Cbl-Interacting Protein 4 (CLIP4), T cell Ubiquitin LigAnd (TULA), or T cell receptor Signaling (STS)-2. It is only found in lymphoid cells and exhibits weak phosphatase activity. UBASH3A facilitates T cell-induced apoptosis through interaction with the apoptosis-inducing factor AIF. It is involved in regulating the level of phosphorylation of the zeta-associated protein (ZAP)-70 tyrosine kinase. TULA proteins contain an N-terminal UBA domain, a central SH3 domain, and a C-terminal histidine phosphatase domain. They bind c-Cbl through the SH3 domain and to ubiquitin via UBA. 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.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*..
gi 20988692 613 QTHRAVFRFIPRHPDELELDVDDPVLV----EAEEDDFWFRGFNMRTGERGVFPAFY 665
Cdd:cd11937   1 QTLRALFQYKPQNIDELMLSPGDYIFVdptqQSEASEGWVIGISHRTGCRGFLPENY 57

Low Density Lipoprotein Receptor Adaptor Protein 1 (LDLRAP1) in mammals and similar proteins Phosphotyrosine-binding (PTB) PH-like fold; The null mutations in the LDL receptor adaptor protein 1 (LDLRAP1) gene, which serves as an adaptor for LDLR endocytosis in the liver, causes autosomal recessive hypercholesterolemia (ARH). LDLRAP1 contains a single PTB domain. PTB domains have a common PH-like fold and are found in various eukaryotic signaling molecules. This domain was initially shown to binds peptides with a NPXY motif with differing requirements for phosphorylation of the tyrosine, although more recent studies have found that some types of PTB domains can bind to peptides lack tyrosine residues altogether. In contrast to SH2 domains, which recognize phosphotyrosine and adjacent carboxy-terminal residues, PTB-domain binding specificity is conferred by residues amino-terminal to the phosphotyrosine. PTB domains are classified into three groups: phosphotyrosine-dependent Shc-like, phosphotyrosine-dependent IRS-like, and phosphotyrosine-independent Dab-like PTB domains. This cd contains mammals, insects, and sponges.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20988692 689 FDVQFLGSVEVPCHQGNGILCAAMQKIATARKltVHLRPPASCDLEISLRGVKLSLSGGGPEFQRCSHFfqmkNISFCGC 768
Cdd:cd13159   5 FYLKYLGSTLVEKPKGEGATAEAVKTIIAMAK--ASGKKLQKVTLTVSPKGIKVTDSATNETILEVSIY----RISYCTA 78

                        90       100       110       120
                ....*....|....*....|....*....|....*....|....
gi 20988692 769 HPRNSCYFGFITKHPLLSRFACHVFV-SQESM-RPVARSVGRAF 810
Cdd:cd13159  79 DANHDKVFAFIATNQDNEKLECHAFLcAKRKMaQAVTLTVAQAF 122

Src Homology 3 domain of the p85 regulatory subunit of Class IA Phosphatidylinositol 3-kinases; Class I PI3Ks convert PtdIns(4,5)P2 to the critical second messenger PtdIns(3,4,5)P3. They are heterodimers and exist in multiple isoforms consisting of one catalytic subunit (out of four isoforms) and one of several regulatory subunits. Class IA PI3Ks associate with the p85 regulatory subunit family, which contains SH3, RhoGAP, and SH2 domains. The p85 subunits recruit the PI3K p110 catalytic subunit to the membrane, where p110 phosphorylates inositol lipids. Vertebrates harbor two p85 isoforms, called alpha and beta. 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 20988692 615 HRAVFRFIPRHPDELELDVDDPVLVE---------------AEEDDFWFRGFNMRTGERGVFPAFY 665
Cdd:cd11776   3 YRALYDYEKERDEDIILKTGDVLVVEnpellalgvpdgketVPKPEGWLEGKNERTGERGDFPGTY 68

Src homology 3 domain of Nitric Oxide Synthase TRaffic INducer; Nostrin is expressed in endothelial and epithelial cells and is involved in the regulation, trafficking and targeting of endothelial NOS (eNOS). It facilitates the endocytosis of eNOS by coordinating the functions of dynamin and the Wiskott-Aldrich syndrome protein (WASP). Increased expression of Nostrin may be correlated to preeclampsia. Nostrin contains an N-terminal F-BAR domain and a C-terminal 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 20988692 616 RAVFRFIPRHPDELELDVDDPVLVEAEEDDFWFRGfNMRtGERGVFPAFY 665
Cdd:cd11823   3 KALYSYTANREDELSLQPGDIIEVHEKQDDGWWLG-ELN-GKKGIFPATY 50

Src homology 3 domain of the Rho guanine nucleotide exchange factors ARHGEF5 and ARHGEF19; ARHGEF5, also called ephexin-3 or TIM (Transforming immortalized mammary oncogene), is a potent activator of RhoA and it plays roles in regulating cell shape, adhesion, and migration. It binds to the SH3 domain of Src and is involved in regulating Src-induced podosome formation. ARHGEF19, also called ephexin-2 or WGEF (weak-similarity GEF), is highly expressed in the intestine, liver, heart and kidney. It activates RhoA, Cdc42, and Rac 1, and has been shown to activate RhoA in the Wnt-PCP (planar cell polarity) pathway. It is involved in the regulation of cell polarity and cytoskeletal reorganization. ARHGEF5 and ARHGEF19 contain RhoGEF (also called Dbl-homologous or DH), Pleckstrin Homology (PH), and SH3 domains. The SH3 domains of ARHGEFs play an autoinhibitory role through intramolecular interactions with a proline-rich region N-terminal to the DH 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 20988692 621 FIPRHPDELELDVDDPVLVEAEEDDFWFRGFNMRTGERGVFPAFY 665
Cdd:cd11940   8 YKAQENDELTLEKADIIMVRQQSSDGWLEGVRLSDGERGWFPQSH 52

Src Homology 3 domain of Sorting nexin 18; SNX18 is localized to peripheral endosomal structures, and acts in a trafficking pathway that is clathrin-independent but relies on AP-1 and PACS1. It binds FIP5 and is required for apical lumen formation. It may also play a role in axonal elongation. SNXs are Phox homology (PX) domain containing proteins that are involved in regulating membrane traffic and protein sorting in the endosomal system. SNX18 also contains BAR and SH3 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 20988692 616 RAVFRFIPRHPDELELDVDDPVLVEAEED-DFWFRGFNMRtGERGVFPAFY 665
Cdd:cd11897   3 RALYDFRSENPGEISLREHEVLSLCSEQDiEGWLEGVNSR-GDRGLFPASY 52

First N-terminal Src homology 3 domain of Dynamin Binding Protein, also called Tuba; DNMBP or Tuba is a cdc42-specific guanine nucleotide exchange factor (GEF) that contains four N-terminal SH3 domains, a central RhoGEF [or Dbl homology (DH)] domain followed by a Bin/Amphiphysin/Rvs (BAR) domain, and two C-terminal SH3 domains. It provides a functional link between dynamin and key regulatory proteins of the actin cytoskeleton. It plays an important role in regulating cell junction configuration. The four N-terminal SH3 domains of DNMBP binds the GTPase dynamin, which plays an important role in the fission of endocytic vesicles. 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 20988692 616 RAVFRFIPRHPDELELDVDDPVLVEAEEDDFWFRGFNMrtGERGVFP 662
Cdd:cd11794   3 RAIFDFCPSVSEELPLFAGDVIEVLKVVDEFWLLGTKE--GVTGQFP 47

Src Homology 3 domain of fungal BOI-like proteins; This subfamily includes the Saccharomyces cerevisiae proteins BOI1 and BOI2, and similar proteins. They contain an N-terminal SH3 domain, a Sterile alpha motif (SAM), and a Pleckstrin homology (PH) domain at the C-terminus. BOI1 and BOI2 interact with the SH3 domain of Bem1p, a protein involved in bud formation. They promote polarized cell growth and participates in the NoCut signaling pathway, which is involved in the control of cytokinesis. SH3 domains bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs; they play a role in the regulation of enzymes by intramolecular interactions, changing the subcellular localization of signal pathway components and mediate multiprotein complex assemblies.

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                ....*....|....*....|....*....|....*....|....*....|...
gi 20988692 616 RAVFRFIPRHPDELELDVDDPV-LVEAEED--DFWFRGFNMRTGERGVFPAFY 665
Cdd:cd11886   3 IVIHDFNARSEDELTLKPGDKIeLIEDDEEfgDGWYLGRNLRTGETGLFPVVF 55

Src homology 3 domain of the Rho guanine nucleotide exchange factor, ephexin-1 (also called NGEF or ARHGEF27); Ephexin-1, also called NGEF (neuronal GEF) or ARHGEF27, activates RhoA, Tac1, and Cdc42 by exchanging bound GDP for free GTP. It is expressed mainly in the brain in a region associated with movement control. It regulates the stability of postsynaptic acetylcholine receptor (AChR) clusters and thus, plays a critical role in the maturation and neurotransmission of neuromuscular junctions. Ephexin-1 directly interacts with the ephrin receptor EphA4 and their coexpression enhances the ability of ephexin-1 to activate RhoA. It is required for normal axon growth and EphA-induced growth cone collapse. Ephexin-1 contains RhoGEF (also called Dbl-homologous or DH), Pleckstrin Homology (PH), and SH3 domains. The SH3 domains of ARHGEFs play an autoinhibitory role through intramolecular interactions with a proline-rich region N-terminal to the DH 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.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*.
gi 20988692 618 VFRFIPRHPDELELDVDDPVLVEAEEDDFWFRGFNMRTGERGVFPA 663
Cdd:cd11939   5 VHPYVSQEPDELSLELADVLNILDKTDDGWIFGERLHDQERGWFPS 50

First C-terminal Src homology 3 domain of SH3 and cysteine-rich domain-containing (Stac) proteins; Stac proteins are putative adaptor proteins that contain a cysteine-rich C1 domain and one or two SH3 domains at the C-terminus. There are three mammalian members (Stac1, Stac2, and Stac3) of this family. Stac1 and Stac3 contain two SH3 domains while Stac2 contains a single SH3 domain at the C-terminus. This model represents the first C-terminal SH3 domain of Stac1 and Stac3, and the single C-terminal SH3 domain of Stac2. Stac1 and Stac2 have been found to be expressed differently in mature dorsal root ganglia (DRG) neurons. Stac1 is mainly expressed in peptidergic neurons while Stac2 is found in a subset of nonpeptidergic and all trkB+ neurons. 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 20988692 614 THRAVFRFIPRHPDELELDVDDPVLVEAEEDDFWFRGfnmRTGER-GVFPAFYAH 667
Cdd:cd11833   1 TYVALYKFKPQENEDLEMRPGDKITLLDDSNEDWWKG---KIEDRvGFFPANFVQ 52

Src homology 3 domain of ArfGAP with SH3 domain, ankyrin repeat and PH domain containing proteins; ASAPs are Arf GTPase activating proteins (GAPs) and they function in regulating cell growth, migration, and invasion. They contain an N-terminal BAR domain, followed by a Pleckstrin homology (PH) domain, an Arf GAP domain, ankyrin (ANK) repeats, and a C-terminal SH3 domain. Vertebrates contain at least three members, ASAP1, ASAP2, and ASAP3, but some ASAP3 proteins do not seem to harbor a C-terminal SH3 domain. ASAP1 and ASAP2 show GTPase activating protein (GAP) activity towards Arf1 and Arf5. They do not show GAP activity towards Arf6, but are able to mediate Arf6 signaling by binding stably to GTP-Arf6. ASAP3 is an Arf6-specific GAP. 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.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*....
gi 20988692 616 RAVFRFIPRHPDELELDVDDPVLVEAEEDDFWFRGFNMRTGER-GVFPA 663
Cdd:cd11821   3 RALYDCQADNDDELTFSEGEIIVVTGEEDDEWWEGHIEGDPSRrGVFPV 51