The Bin/Amphiphysin/Rvs (BAR) domain of Amphiphysin I and II; BAR domains are dimerization, lipid binding and curvature sensing modules found in many different proteins with diverse functions. Amphiphysins function primarily in endocytosis and other membrane remodeling events. They 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. 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. 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. The N-BAR domain of amphiphysin forms a curved dimer with a positively-charged concave face that can drive membrane bending and curvature. Human autoantibodies to amphiphysin-1 hinder GABAergic signaling and contribute to the pathogenesis of paraneoplastic stiff-person syndrome. Mutations in amphiphysin-2 (BIN1) are associated with autosomal recessive centronuclear myopathy.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1934025863  26 QKLGKADETKDEQFEEYVQNFKRQEAEGTRLQRELRGYLAAIKGMQEASMKLTESLHEVYEPDWYGREDVKMVGEKCDVL 105
Cdd:cd07611     1 QKLGKADETKDEQFEEYVQNFKRQETEGTRLQRELRAYLAAIKGMQEASKKLTESLHEVYEPDWYGRDDVKTIGEKCDLL 80

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1934025863 106 WEDFHQKLVDGSLLTLDTYLGQFPDIKNRIAKRSRKLVDYDSARHHLEALQSSKRKDESRISKAEEEFQKAQKVFEEFNV 185
Cdd:cd07611    81 WEDFHQKLVDGALLTLDTYLGQFPDIKNRIAKRSRKLVDYDSARHHLEALQTSKRKDEGRIAKAEEEFQKAQKVFEEFNV 160

                         170       180       190       200       210
                  ....*....|....*....|....*....|....*....|....*....|.
gi 1934025863 186 DLQEELPSLWSRRVGFYVNTFKNVSSLEAKFHKEIAVLCHKLYEVMTKLGD 236
Cdd:cd07611   161 DLQEELPSLWSRRVGFYVNTFKNVSSLEAKFHKEISVLCHKLYEVMTKLGE 211

The Bin/Amphiphysin/Rvs (BAR) domain of Amphiphysin I and II; BAR domains are dimerization, lipid binding and curvature sensing modules found in many different proteins with diverse functions. Amphiphysins function primarily in endocytosis and other membrane remodeling events. They 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. 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. 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. The N-BAR domain of amphiphysin forms a curved dimer with a positively-charged concave face that can drive membrane bending and curvature. Human autoantibodies to amphiphysin-1 hinder GABAergic signaling and contribute to the pathogenesis of paraneoplastic stiff-person syndrome. Mutations in amphiphysin-2 (BIN1) are associated with autosomal recessive centronuclear myopathy.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1934025863  26 QKLGKADETKDEQFEEYVQNFKRQEAEGTRLQRELRGYLAAIKGMQEASMKLTESLHEVYEPDWYGREDVKMVGEKCDVL 105
Cdd:cd07611     1 QKLGKADETKDEQFEEYVQNFKRQETEGTRLQRELRAYLAAIKGMQEASKKLTESLHEVYEPDWYGRDDVKTIGEKCDLL 80

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1934025863 106 WEDFHQKLVDGSLLTLDTYLGQFPDIKNRIAKRSRKLVDYDSARHHLEALQSSKRKDESRISKAEEEFQKAQKVFEEFNV 185
Cdd:cd07611    81 WEDFHQKLVDGALLTLDTYLGQFPDIKNRIAKRSRKLVDYDSARHHLEALQTSKRKDEGRIAKAEEEFQKAQKVFEEFNV 160

                         170       180       190       200       210
                  ....*....|....*....|....*....|....*....|....*....|.
gi 1934025863 186 DLQEELPSLWSRRVGFYVNTFKNVSSLEAKFHKEIAVLCHKLYEVMTKLGD 236
Cdd:cd07611   161 DLQEELPSLWSRRVGFYVNTFKNVSSLEAKFHKEISVLCHKLYEVMTKLGE 211

BAR domain; BAR domains are dimerization, lipid binding and curvature sensing modules found in many different protein families. A BAR domain with an additional N-terminal amphipathic helix (an N-BAR) can drive membrane curvature. These N-BAR domains are found in amphiphysin, endophilin, BRAP and Nadrin. BAR domains are also frequently found alongside domains that determine lipid specificity, like pfam00169 and pfam00787 domains in beta centaurins and sorting nexins respectively.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1934025863  13 VQKRLNRAQEKVLQKLGKADETK-DEQFEEYVQNFKRQEAEGTRLQRELRGYLAAIKGMQEASM-------KLTESLHEV 84
Cdd:pfam03114   1 LKKQFNRASQLLGEKVGGAEKTKlDEDFEELERRFDTTEKEIKKLQKDTKGYLQPNPGARAKQTvleqpeeLLAESMIEA 80

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1934025863  85 YEPDWYGR------EDVKMVGEKCDVLWEDFHQKLVDGSLLTLDTYLGQFPDIKNRIAKRSRKLVDYDSARHHLEALQSS 158
Cdd:pfam03114  81 GKDLGEDSsfgkalEDYGEALKRLAQLLEQLDDRVETNFLDPLRNLLKEFKEIQKHRKKLERKRLDYDAAKTRVKKAKKK 160

                         170       180       190       200       210       220       230
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 1934025863 159 KRKDESRISKAEEEFQKAQKVFEEFNVDLQEELPSLWSRRVGFYVNTFKNVSSLEAKFHKEIAVLCHKLYEVMTK 233
Cdd:pfam03114 161 KSSKAKDESQAEEELRKAQAKFEESNEQLKALLPNLLSLEVEFVVNQLVAFVEAQLDFHRQCYQLLEQLQQQLGK 235

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        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 1934025863  759 YKVETLHDFEAANSDELTLQRGDVVLVVpsdseADQDAGWLVGVKESDwlqyrdlatYKGLFPENFTR 826
Cdd:smart00326   3 PQVRALYDYTAQDPDELSFKKGDIITVL-----EKSDDGWWKGRLGRG---------KEGLFPSNYVE 56

The Bin/Amphiphysin/Rvs (BAR) domain of Amphiphysin I and II; BAR domains are dimerization, lipid binding and curvature sensing modules found in many different proteins with diverse functions. Amphiphysins function primarily in endocytosis and other membrane remodeling events. They 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. 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. 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. The N-BAR domain of amphiphysin forms a curved dimer with a positively-charged concave face that can drive membrane bending and curvature. Human autoantibodies to amphiphysin-1 hinder GABAergic signaling and contribute to the pathogenesis of paraneoplastic stiff-person syndrome. Mutations in amphiphysin-2 (BIN1) are associated with autosomal recessive centronuclear myopathy.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1934025863  26 QKLGKADETKDEQFEEYVQNFKRQEAEGTRLQRELRGYLAAIKGMQEASMKLTESLHEVYEPDWYGREDVKMVGEKCDVL 105
Cdd:cd07611     1 QKLGKADETKDEQFEEYVQNFKRQETEGTRLQRELRAYLAAIKGMQEASKKLTESLHEVYEPDWYGRDDVKTIGEKCDLL 80

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1934025863 106 WEDFHQKLVDGSLLTLDTYLGQFPDIKNRIAKRSRKLVDYDSARHHLEALQSSKRKDESRISKAEEEFQKAQKVFEEFNV 185
Cdd:cd07611    81 WEDFHQKLVDGALLTLDTYLGQFPDIKNRIAKRSRKLVDYDSARHHLEALQTSKRKDEGRIAKAEEEFQKAQKVFEEFNV 160

                         170       180       190       200       210
                  ....*....|....*....|....*....|....*....|....*....|.
gi 1934025863 186 DLQEELPSLWSRRVGFYVNTFKNVSSLEAKFHKEIAVLCHKLYEVMTKLGD 236
Cdd:cd07611   161 DLQEELPSLWSRRVGFYVNTFKNVSSLEAKFHKEISVLCHKLYEVMTKLGE 211

The Bin/Amphiphysin/Rvs (BAR) domain of Bridging integrator 2; BAR domains are dimerization, lipid binding and curvature sensing modules found in many different proteins with diverse functions. Bridging integrator 2 (Bin2) is a BAR domain containing protein that is mainly expressed in hematopoietic cells. It is upregulated during granulocyte differentiation and is thought to function primarily in this lineage. The BAR domain of Bin2 is closely related to the BAR domains of amphiphysins, which function primarily in endocytosis and other membrane remodeling events. 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. Unlike amphiphysins, Bin2 does not appear to contain a C-terminal SH3 domain. Amphiphysin I proteins, enriched in the brain and nervous system, function in synaptic vesicle endocytosis. Some amphiphysin II isoforms, also called Bridging integrator 1 (Bin1), function in intracellular vessicle trafficking. Bin2 can form a stable complex with Bin1 in cells but cannot replace the function of Bin1, and thus, appears to harbor a nonredundant function. The N-BAR domain of amphiphysin forms a curved dimer with a positively-charged concave face that can drive membrane bending and curvature.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1934025863  26 QKLGKADETKDEQFEEYVQNFKRQEAEGTRLQRELRGYLAAIKGMQEASMKLTESLHEVYEPDWYGREDVKMVGEKCDVL 105
Cdd:cd07612     1 QKLGKTVETKDEQFEQCAMNLNMQQSDGNRLYKDLKAYLNAVKVMHESSKRLSQTLQDIYEPDWDGHEDLGAIVEGEDLL 80

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1934025863 106 WEDFHQKLVDGSLLTLDTYLGQFPDIKNRIAKRSRKLVDYDSARHHLEALQSSKRKDESRISKAEEEFQKAQKVFEEFNV 185
Cdd:cd07612    81 WNDYEAKLHDQALRTMESYMAQFPDVKERVAKRGRKLVDYDSARHHLEALQNAKKKDDAKIAKAEEEFNRAQVVFEDINR 160

                         170       180       190       200       210
                  ....*....|....*....|....*....|....*....|....*....|.
gi 1934025863 186 DLQEELPSLWSRRVGFYVNTFKNVSSLEAKFHKEIAVLCHKLYEVMTKLGD 236
Cdd:cd07612   161 ELREELPILYDSRIGCYVTVFQNISNLRDTFYKEMSKLNHDLYNVMKKLED 211

BAR domain; BAR domains are dimerization, lipid binding and curvature sensing modules found in many different protein families. A BAR domain with an additional N-terminal amphipathic helix (an N-BAR) can drive membrane curvature. These N-BAR domains are found in amphiphysin, endophilin, BRAP and Nadrin. BAR domains are also frequently found alongside domains that determine lipid specificity, like pfam00169 and pfam00787 domains in beta centaurins and sorting nexins respectively.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1934025863  13 VQKRLNRAQEKVLQKLGKADETK-DEQFEEYVQNFKRQEAEGTRLQRELRGYLAAIKGMQEASM-------KLTESLHEV 84
Cdd:pfam03114   1 LKKQFNRASQLLGEKVGGAEKTKlDEDFEELERRFDTTEKEIKKLQKDTKGYLQPNPGARAKQTvleqpeeLLAESMIEA 80

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1934025863  85 YEPDWYGR------EDVKMVGEKCDVLWEDFHQKLVDGSLLTLDTYLGQFPDIKNRIAKRSRKLVDYDSARHHLEALQSS 158
Cdd:pfam03114  81 GKDLGEDSsfgkalEDYGEALKRLAQLLEQLDDRVETNFLDPLRNLLKEFKEIQKHRKKLERKRLDYDAAKTRVKKAKKK 160

                         170       180       190       200       210       220       230
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 1934025863 159 KRKDESRISKAEEEFQKAQKVFEEFNVDLQEELPSLWSRRVGFYVNTFKNVSSLEAKFHKEIAVLCHKLYEVMTK 233
Cdd:pfam03114 161 KSSKAKDESQAEEELRKAQAKFEESNEQLKALLPNLLSLEVEFVVNQLVAFVEAQLDFHRQCYQLLEQLQQQLGK 235

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        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 1934025863 757 FLYKVETLHDFEAANSDELTLQRGDVVLVVPSDSEADQDAGWLVGVKESDwlqyrdlaTYKGLFPENFTRRL 828
Cdd:cd11790     1 VLYKVRATHDYTAEDTDELTFEKGDVILVIPFDDPEEQDEGWLMGVKEST--------GCRGVFPENFTERI 64

Src Homology 3 domain of Bridging integrator 1 (Bin1), also called Amphiphysin-2; Bin1 isoforms are localized in many different tissues and may function in intracellular vesicle trafficking. It plays a role in the organization and maintenance of the T-tubule network in skeletal muscle. Mutations in Bin1 are associated with autosomal recessive centronuclear myopathy. Bin1 contains an N-terminal BAR domain with an additional N-terminal amphipathic helix (an N-BAR) and a C-terminal SH3 domain. The SH3 domain of Bin1 forms transient complexes with actin, myosin filaments, and CDK5, to facilitate sarcomere organization and myofiber maturation. It also binds dynamin and prevents its self-assembly. 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        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 1934025863 757 FLYKVETLHDFEAANSDELTLQRGDVVLVVPSDSEADQDAGWLVGVKESDWLQYRDLATYKGLFPENFTRRL 828
Cdd:cd12139     1 FLFKVQAQHDYTATDTDELQLKAGDVVLVIPFQNPEEQDEGWLMGVKESDWNQHKKLEKCRGVFPENFTERV 72

The Bin/Amphiphysin/Rvs (BAR) domain of Saccharomyces cerevisiae Reduced viability upon starvation protein 167 and similar proteins; BAR domains are dimerization, lipid binding and curvature sensing modules found in many different proteins with diverse functions. This subfamily is composed of fungal proteins with similarity to Saccharomyces cerevisiae Reduced viability upon starvation protein 167 (Rvs167p) and Schizosaccharomyces pombe Hob1 (homolog of Bin1). S. cerevisiae Rvs167p plays a role in regulation of the actin cytoskeleton, endocytosis, and sporulation. It forms a heterodimer with another BAR domain protein Rvs161p. Rvs161p and Rvs167p share common functions but are not interchangeable. Their BAR domains cannot be replaced with each other and the overexpression of one cannot suppress the mutant phenotypes of the other. Rvs167p also interacts with the GTPase activating protein (GAP) Gyp5p, which is involved in ER to Golgi vesicle trafficking. BAR domains form dimers that bind to membranes, induce membrane bending and curvature, and may also be involved in protein-protein interactions.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1934025863  36 DEQFEEYVQNFKRQEAEGTRLQRELRGYLAAIKGMQEASMKLTESLHEVYEPdwygredvkMVGEKCDVL---------- 105
Cdd:cd07599     1 DEQFEELEKDFKSLEKSLKKLIEQSKAFRDSWRSILTHQIAFAKEFAELYDP---------IVGPKESVGshpapestla 71

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1934025863 106 ----WEDFHQKLVDGSLLTLDTY-----------LGQFPDIKNRIAKRSRKLVDYDSARHHLEALQSSKR----KDESRI 166
Cdd:cd07599    72 rlsrYVKALEELKKELLEELEFFeervilpakelKKYIKKIRKTIKKRDHKKLDYDKLQNKLNKLLQKKKelslKDEKQL 151

                         170       180
                  ....*....|....*....|....*...
gi 1934025863 167 SKAEEEFQKAQKVFEEFNVDLQEELPSL 194
Cdd:cd07599   152 AKLERKLEEAKEEYEALNELLKSELPKL 179

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        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 1934025863  759 YKVETLHDFEAANSDELTLQRGDVVLVVpsdseADQDAGWLVGVKESDwlqyrdlatYKGLFPENFTR 826
Cdd:smart00326   3 PQVRALYDYTAQDPDELSFKKGDIITVL-----EKSDDGWWKGRLGRG---------KEGLFPSNYVE 56

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.

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 1934025863 760 KVETLHDFEAANSDELTLQRGDVVLVVPSDSEadqdaGWLVGVKESDwlqyrdlatYKGLFPENF 824
Cdd:cd00174     1 YARALYDYEAQDDDELSFKKGDIITVLEKDDD-----GWWEGELNGG---------REGLFPANY 51

Src Homology 3 domain of Mixed Lineage Kinase 4; MLK4 is a Serine/Threonine Kinase (STK), catalyzing the transfer of the gamma-phosphoryl group from ATP to S/T residues on protein substrates. MLKs act as mitogen-activated protein kinase kinase kinases (MAP3Ks, MKKKs, MAPKKKs), which phosphorylate and activate MAPK kinases (MAPKKs or MKKs or MAP2Ks), which in turn phosphorylate and activate MAPKs during signaling cascades that are important in mediating cellular responses to extracellular signals. MLKs play roles in immunity and inflammation, as well as in cell death, proliferation, and cell cycle regulation. The specific function of MLK4 is yet to be determined. Mutations in the kinase domain of MLK4 have been detected in colorectal cancers. MLK4 contains an SH3 domain, a catalytic kinase domain, a leucine zipper, a proline-rich region, and a CRIB domain that mediates binding to GTP-bound Cdc42 and Rac. 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        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....
gi 1934025863 764 LHDFEAANSDELTLQRGDVVLVVPSDSEADQDAGWLVGVkesdwLQYRdlatyKGLFPENFTRR 827
Cdd:cd12058     5 LYDYEASGEDELSLRRGDVVEVLSQDAAVSGDDGWWAGK-----IRHR-----LGIFPANYVTR 58

Src homology 3 domain of ephexin-1-like SH3 domain containing Rho guanine nucleotide exchange factors; Members of this family contain RhoGEF (also called Dbl-homologous or DH), Pleckstrin Homology (PH), and C-terminal SH3 domains. They include the Rho guanine nucleotide exchange factors ARHGEF5, ARHGEF16, ARHGEF19, ARHGEF26, ARHGEF27 (also called ephexin-1), and similar proteins, and are also called ephexins because they interact directly with ephrin A receptors. GEFs interact with Rho GTPases via their DH domains to catalyze nucleotide exchange by stabilizing the nucleotide-free GTPase intermediate. They play important roles in neuronal development. 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        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 1934025863 761 VETLHDFEAANSDELTLQRGDVVLVvpSDSEADqdaGWLVGVKesdwlqYRDLAtyKGLFPENFTR 826
Cdd:cd11793     2 VQCVHAYTAQQPDELTLEEGDVVNV--LRKMPD---GWYEGER------LRDGE--RGWFPSSYTE 54

Variant SH3 domain;

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|...
gi 1934025863 764 LHDFEAANSDELTLQRGDVVLVVPSDSEadqdaGWLVGVKESDWlqyrdlatykGLFPENFTR 826
Cdd:pfam14604   2 LYPYEPKDDDELSLQRGDVITVIEESED-----GWWEGINTGRT----------GLVPANYVE 49

First Src Homology 3 domain (SH3A) of CD2-associated protein and similar proteins; This subfamily is composed of the first SH3 domain (SH3A) of CD2AP, CIN85 (Cbl-interacting protein of 85 kDa), and similar domains. CD2AP and CIN85 are adaptor proteins that bind to protein partners and assemble complexes that have been implicated in T cell activation, kidney function, and apoptosis of neuronal cells. They also associate with endocytic proteins, actin cytoskeleton components, and other adaptor proteins involved in receptor tyrosine kinase (RTK) signaling. CD2AP and the main isoform of CIN85 contain three SH3 domains, a proline-rich region, and a C-terminal coiled-coil domain. All of these domains enable CD2AP and CIN85 to bind various protein partners and assemble complexes that have been implicated in many different functions. SH3A of both proteins bind to an atypical PXXXPR motif at the C-terminus of Cbl and the cytoplasmic domain of the cell adhesion protein CD2. CIN85 SH3A binds to internal proline-rich motifs within the proline-rich region; this intramolecular interaction serves as a regulatory mechanism to keep CIN85 in a closed conformation, preventing the recruitment of other proteins. CIN85 SH3A has also been shown to bind ubiquitin. 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        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|...
gi 1934025863 764 LHDFEAANSDELTLQRGDVVLVVPSDSEadqdaGWLVGvkesdwlqyrDLATYKGLFPENFTR 826
Cdd:cd11873     5 EFDYDAEEPDELTLKVGDIITNVKKMEE-----GWWEG----------TLNGKRGMFPDNFVK 52

Src homology 3 domain of Signal Transducing Adaptor Molecule 1; STAM1 is part of the endosomal sorting complex required for transport (ESCRT-0) and is involved in sorting ubiquitinated cargo proteins from the endosome. It may also be involved in the regulation of IL2 and GM-CSF mediated signaling, and has been implicated in neural cell survival. STAMs were discovered as proteins that are highly phosphorylated following cytokine and growth factor stimulation. They function in cytokine signaling and surface receptor degradation, as well as regulate Golgi morphology. They associate with many proteins including Jak2 and Jak3 tyrosine kinases, Hrs, AMSH, and UBPY. STAM adaptor proteins contain VHS (Vps27, Hrs, STAM homology), ubiquitin interacting (UIM), 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.

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 1934025863 760 KVETLHDFEAANSDELTLQRGDVVLVVPsdseaDQDAGWLVGvkesdwlqyrdlATYK--GLFPENF 824
Cdd:cd11964     2 KVRAIYDFEAAEDNELTFKAGDIITILD-----DSDPNWWKG------------ETPQgtGLFPSNF 51

First Src homology 3 domain (or SH3A) of Intersectin; Intersectins (ITSNs) are adaptor proteins that function in exo- and endocytosis, actin cytoskeletal reorganization, and signal transduction. They are essential for initiating clathrin-coated pit formation. They bind to many proteins through their multidomain structure and facilitate the assembly of multimeric complexes. Vertebrates contain two ITSN proteins, ITSN1 and ITSN2, which exist in alternatively spliced short and long isoforms. The short isoforms contain two Eps15 homology domains (EH1 and EH2), a coiled-coil region and five SH3 domains (SH3A-E), while the long isoforms, in addition, contain RhoGEF (also called Dbl-homologous or DH), Pleckstrin homology (PH) and C2 domains. ITSN1 and ITSN2 are both widely expressed, with variations depending on tissue type and stage of development. The first SH3 domain (or SH3A) of ITSN1 has been shown to bind many proteins including Sos1, dynamin1/2, CIN85, c-Cbl, PI3K-C2, SHIP2, N-WASP, and CdGAP, 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.

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                  ....*....|....*....|....*....|....*....|....*....|....*....|.
gi 1934025863 764 LHDFEAANSDELTLQRGDVVLVvpsDSEADQDAGWLVGvkesdwlqyrDLATYKGLFPENF 824
Cdd:cd11836     5 LYAFEARNPDEISFQPGDIIQV---DESQVAEPGWLAG----------ELKGKTGWFPANY 52

Src homology 3 domain of Signal Transducing Adaptor Molecule 2; STAM2, also called EAST (Epidermal growth factor receptor-associated protein with SH3 and TAM domain) or Hbp (Hrs binding protein), is part of the endosomal sorting complex required for transport (ESCRT-0). It plays a role in sorting mono-ubiquinated endosomal cargo for trafficking to the lysosome for degradation. It is also involved in the regulation of exocytosis. STAMs were discovered as proteins that are highly phosphorylated following cytokine and growth factor stimulation. They function in cytokine signaling and surface receptor degradation, as well as regulate Golgi morphology. They associate with many proteins including Jak2 and Jak3 tyrosine kinases, Hrs, AMSH, and UBPY. STAM adaptor proteins contain VHS (Vps27, Hrs, STAM homology), ubiquitin interacting (UIM), 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.

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 1934025863 760 KVETLHDFEAANSDELTLQRGDVVLVVPsdseaDQDAGWLVGVkesdwlQYRDLatykGLFPENF 824
Cdd:cd11963     3 KVRALYDFEAVEDNELTFKHGEIIIVLD-----DSDANWWKGE------NHRGV----GLFPSNF 52

Src homology 3 domain of Abl Interactor proteins; Abl interactor (Abi) proteins are adaptor proteins serving as binding partners and substrates of Abl tyrosine kinases. They are involved in regulating actin cytoskeletal reorganization and play important roles in membrane-ruffling, endocytosis, cell motility, and cell migration. They localize to sites of actin polymerization in epithelial adherens junction and immune synapses, as well as to the leading edge of lamellipodia. Vertebrates contain two Abi proteins, Abi1 and Abi2. Abi1 displays a wide expression pattern while Abi2 is highly expressed in the eye and brain. Abi proteins contain a homeobox homology domain, a proline-rich region, and a SH3 domain. The SH3 domain of Abi binds to a PxxP motif in Abl. 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 1934025863 760 KVETLHDFEAANSDELTLQRGDVVLVVpsdseADQDAGWLVGVkesdwlqyrdLATYKGLFPENF 824
Cdd:cd11826     1 KVVALYDYTADKDDELSFQEGDIIYVT-----KKNDDGWYEGV----------LNGVTGLFPGNY 50

Second Src Homology 3 domain of Bzz1 and similar domains; Bzz1 (or Bzz1p) is a WASP/Las17-interacting protein involved in endocytosis and trafficking to the vacuole. It physically interacts with type I myosins and functions in the early steps of endocytosis. Together with other proteins, it induces membrane scission in yeast. Bzz1 contains an N-terminal F-BAR (FES-CIP4 Homology and Bin/Amphiphysin/Rvs), a central coiled-coil, and two C-terminal SH3 domains. This model represents the second 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.

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 1934025863 760 KVETLHDFEAANSDELTLQRGDVVLVVpsdsEADQDAGWLVGvkesdwlqyrDLATYKGLFPENF 824
Cdd:cd11778     1 YVEALYDYEAQGDDEISIRVGDRIAVI----RGDDGSGWTYG----------EINGVKGLFPTSY 51

The Bin/Amphiphysin/Rvs (BAR) domain of Sorting Nexins; BAR domains are dimerization, lipid binding and curvature sensing modules found in many different proteins with diverse functions. Sorting nexins (SNXs) are Phox homology (PX) domain containing proteins that are involved in regulating membrane traffic and protein sorting in the endosomal system. SNXs differ from each other in their lipid-binding specificity, subcellular localization and specific function in the endocytic pathway. A subset of SNXs also contain BAR domains. The PX-BAR structural unit determines the specific membrane targeting of SNXs. BAR domains form dimers that bind to membranes, induce membrane bending and curvature, and may also be involved in protein-protein interactions.

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                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1934025863 120 TLDTYLGQFPDIKNRIAKRSRKLVDYDSARHHLEALQSSKRKD--------------ESRISKAEEEFQKAQKVFEEFNV 185
Cdd:cd07596    94 PLKEYLRYCQAVKETLDDRADALLTLQSLKKDLASKKAQLEKLkaapgikpakveelEEELEEAESALEEARKRYEEISE 173

                          90       100       110
                  ....*....|....*....|....*....|....*.
gi 1934025863 186 DLQEELPSLWSRRVGFYVNTFKNVSSLEAKFHKEIA 221
Cdd:cd07596   174 RLKEELKRFHEERARDLKAALKEFARLQVQYAEKIA 209

First Src Homology 3 domain (SH3A) of Cbl-interacting protein of 85 kDa; CIN85, also called SH3 domain-containing kinase-binding protein 1 (SH3KBP1) or CD2-binding protein 3 (CD2BP3) or Ruk, is an adaptor protein that is involved in the downregulation of receptor tyrosine kinases by facilitating endocytosis through interaction with endophilin-associated ubiquitin ligase Cbl proteins. It is also important in many other cellular processes including vesicle-mediated transport, cytoskeletal remodelling, apoptosis, cell adhesion and migration, and viral infection, among others. CIN85 exists as multiple variants from alternative splicing; the main variant contains three SH3 domains, a proline-rich region, and a C-terminal coiled-coil domain. All of these domains enable CIN85 to bind various protein partners and assemble complexes that have been implicated in many different functions. This alignment model represents the first SH3 domain (SH3A) of CIN85; SH3A binds to internal proline-rich motifs within the proline-rich region. This intramolecular interaction serves as a regulatory mechanism to keep CIN85 in a closed conformation, preventing the recruitment of other proteins. SH3A has also been shown to bind ubiquitin and to an atypical PXXXPR motif at the C-terminus of Cbl and the cytoplasmic end of the cell adhesion protein CD2. 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        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|.
gi 1934025863 766 DFEAANSDELTLQRGDVVLVVPSDseadqDAGWLVGvkesdwlqyrDLATYKGLFPENFTR 826
Cdd:cd12052     7 DYKAQHEDELTITVGDIITKIKKD-----DGGWWEG----------EIKGRRGLFPDNFVR 52

Third Src Homology 3 domain (SH3C) of CD2-associated protein; CD2AP, also called CMS (Cas ligand with Multiple SH3 domains) or METS1 (Mesenchyme-to-Epithelium Transition protein with SH3 domains), is a cytosolic adaptor protein that plays a role in regulating the cytoskeleton. It is critical in cell-to-cell union necessary for kidney function. It also stabilizes the contact between a T cell and antigen-presenting cells. It is primarily expressed in podocytes at the cytoplasmic face of the slit diaphragm and serves as a linker anchoring podocin and nephrin to the actin cytoskeleton. CD2AP contains three SH3 domains, a proline-rich region, and a C-terminal coiled-coil domain. All of these domains enable CD2AP to bind various protein partners and assemble complexes that have been implicated in many different functions. This alignment model represents the third SH3 domain (SH3C) of CD2AP. SH3C has been shown to bind ubiquitin. 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        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|..
gi 1934025863 763 TLHDFEAANSDELTLQRGDVVLVVPSDSeadQDAGWLVGvkesdwlqyrDLATYKGLFPENF 824
Cdd:cd12056     6 ALFHYEGTNEDELDFKEGEIILIISKDT---GEPGWWKG----------ELNGKEGVFPDNF 54

Fifth Src homology 3 domain (or SH3E) of Intersectin; Intersectins (ITSNs) are adaptor proteins that function in exo- and endocytosis, actin cytoskeletal reorganization, and signal transduction. They are essential for initiating clathrin-coated pit formation. They bind to many proteins through their multidomain structure and facilitate the assembly of multimeric complexes. Vertebrates contain two ITSN proteins, ITSN1 and ITSN2, which exist in alternatively spliced short and long isoforms. The short isoforms contain two Eps15 homology domains (EH1 and EH2), a coiled-coil region and five SH3 domains (SH3A-E), while the long isoforms, in addition, contain RhoGEF (also called Dbl-homologous or DH), Pleckstrin homology (PH) and C2 domains. ITSN1 and ITSN2 are both widely expressed, with variations depending on tissue type and stage of development. The fifth SH3 domain (or SH3E) of ITSN1 has been shown to bind many protein partners including SGIP1, Sos1, dynamin1/2, CIN85, c-Cbl, SHIP2, N-WASP, and synaptojanin-1, 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        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 1934025863 760 KVETLHDFEAANSDELTLQRGDVVLVVPSDseadqDAGWLVGvkesdwlqyrDLATYKGLFPENF 824
Cdd:cd11840     1 QVIALFPYTAQNEDELSFQKGDIINVLSKD-----DPDWWRG----------ELNGQTGLFPSNY 50

First Src Homology 3 domain (SH3A) of CD2-associated protein; CD2AP, also called CMS (Cas ligand with Multiple SH3 domains) or METS1 (Mesenchyme-to-Epithelium Transition protein with SH3 domains), is a cytosolic adaptor protein that plays a role in regulating the cytoskeleton. It is critical in cell-to-cell union necessary for kidney function. It also stabilizes the contact between a T cell and antigen-presenting cells. It is primarily expressed in podocytes at the cytoplasmic face of the slit diaphragm and serves as a linker anchoring podocin and nephrin to the actin cytoskeleton. CD2AP contains three SH3 domains, a proline-rich region, and a C-terminal coiled-coil domain. All of these domains enable CD2AP to bind various protein partners and assemble complexes that have been implicated in many different functions. This alignment model represents the first SH3 domain (SH3A) of CD2AP. SH3A binds to the PXXXPR motif present in c-Cbl and the cytoplasmic domain of cell adhesion protein CD2. Its interaction with CD2 anchors CD2 at sites of cell contact. 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        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1934025863 759 YKVEtlHDFEAANSDELTLQRGDVVLVVpsdsEADQDAGWLVGvkesdwlqyrDLATYKGLFPENFTRRL 828
Cdd:cd12053     2 YIVE--YDYDAVHEDELTIRVGEIIRNV----KKLEEEGWLEG----------ELNGRRGMFPDNFVKEI 55

Src Homology 3 domain of Sorting Nexin 9 and similar proteins; Sorting nexins (SNXs) are Phox homology (PX) domain containing proteins that are involved in regulating membrane traffic and protein sorting in the endosomal system. SNXs differ from each other in their lipid-binding specificity, subcellular localization and specific function in the endocytic pathway. This subfamily consists of SH3 domain containing SNXs including SNX9, SNX18, SNX33, and similar proteins. SNX9 is localized to plasma membrane endocytic sites and acts primarily in clathrin-mediated endocytosis, while SNX18 is localized to peripheral endosomal structures, and acts in a trafficking pathway that is clathrin-independent but relies on AP-1 and PACS1. 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        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 1934025863 760 KVETLHDFEAANSDELTLQRGDVVLVVPSDSeadqdagwlvgvkESDWLQYRDLATYKGLFPENF 824
Cdd:cd11763     1 KVRALYDFDSQPSGELSLRAGEVLTITRQDV-------------GDGWLEGRNSRGEVGLFPSSY 52

Src homology 3 domain of ArfGAP with SH3 domain, ankyrin repeat and PH domain containing protein 2; ASAP2 is also called DDEF2 (Development and Differentiation Enhancing Factor 2), AMAP2, centaurin beta-3, or PAG3. It mediates the functions of Arf GTPases vial dual mechanisms: it exhibits GTPase activating protein (GAP) activity towards class I (Arf1) and II (Arf5) Arfs; and it binds class III Arfs (GTP-Arf6) stably without GAP activity. It binds paxillin and is implicated in Fcgamma receptor-mediated phagocytosis in macrophages and in cell migration. ASAP2 contains 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. 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        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 1934025863 760 KVETLHDFEAANSDELTLQRGDVVLVvpsDSEADQDagWLVGVKESDwlqyrdlATYKGLFPENF 824
Cdd:cd11966     1 RVKALYNCVADNPDELTFSEGEIIIV---DGEEDKE--WWIGHIDGE-------PTRRGAFPVSF 53

Src Homology 3 domain of Pak Interactive eXchange factors; PIX proteins are Rho guanine nucleotide exchange factors (GEFs), which activate small GTPases by exchanging bound GDP for free GTP. They act as GEFs for both Cdc42 and Rac 1, and have been implicated in cell motility, adhesion, neurite outgrowth, and cell polarity. Vertebrates contain two proteins from the PIX subfamily, alpha-PIX and beta-PIX. Alpha-PIX, also called ARHGEF6, is localized in dendritic spines where it regulates spine morphogenesis. Mutations in the ARHGEF6 gene cause X-linked intellectual disability in humans. Beta-PIX play roles in regulating neuroendocrine exocytosis, focal adhesion maturation, cell migration, synaptic vesicle localization, and insulin secretion. PIX proteins contain an N-terminal SH3 domain followed by RhoGEF (also called Dbl-homologous or DH) and Pleckstrin Homology (PH) domains, and a C-terminal leucine-zipper domain for dimerization. The SH3 domain of PIX binds to an atypical PxxxPR motif in p21-activated kinases (PAKs) with high affinity. The binding of PAKs to PIX facilitate the localization of PAKs to focal complexes and also localizes PAKs to PIX targets Cdc43 and Rac, leading to the activation of PAKs. 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        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 1934025863 760 KVETLHDFEAANSDELTLQRGDVVLVVpsdseADQDAGWLVGvkesdwlqyrDLATYKGLFPENFTR 826
Cdd:cd11877     1 LVRAKFNFEGTNEDELSFDKGDIITVT-----QVVEGGWWEG----------TLNGKTGWFPSNYVK 52

C-terminal Src Homology 3 domain of the Nebulin family of proteins; Nebulin family proteins contain multiple nebulin repeats, and may contain an N-terminal LIM domain and/or a C-terminal SH3 domain. They have molecular weights ranging from 34 to 900 kD, depending on the number of nebulin repeats, and they all bind actin. They are involved in the regulation of actin filament architecture and function as stabilizers and scaffolds for cytoskeletal structures with which they associate, such as long actin filaments or focal adhesions. Nebulin family proteins that contain a C-terminal SH3 domain include the giant filamentous protein nebulin, nebulette, Lasp1, and Lasp2. Lasp2, also called LIM-nebulette, is an alternatively spliced variant of nebulette. 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        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|.
gi 1934025863 764 LHDFEAANSDELTLQRGDVVLVVPSdseadQDAGWLVGVKEsdwlqyRDLATykGLFPENF 824
Cdd:cd11789     5 MYDYAAADDDEVSFQEGDVIINVEI-----IDDGWMEGTVQ------RTGQS--GMLPANY 52

Src homology 3 domain of ArfGAP with SH3 domain, ankyrin repeat and PH domain containing protein 1; ASAP1 is also called DDEF1 (Development and Differentiation Enhancing Factor 1), AMAP1, centaurin beta-4, or PAG2. an Arf GTPase activating protein (GAP) with activity towards Arf1 and Arf5 but not Arf6. However, it has been shown to bind GTP-Arf6 stably without GAP activity. It has been implicated in cell growth, migration, and survival, as well as in tumor invasion and malignancy. It binds paxillin and cortactin, two components of invadopodia which are essential for tumor invasiveness. It also binds focal adhesion kinase (FAK) and the SH2/SH3 adaptor CrkL. ASAP1 contains 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. 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        60
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gi 1934025863 760 KVETLHDFEAANSDELTLQRGDVVLVVpsdseADQDAGWLVGVKESdwlqyrdLATYKGLFPENFTRRL 828
Cdd:cd11965     1 RVKTIYDCQADNDDELTFVEGEVIIVT-----GEEDQEWWIGHIEG-------QPERKGVFPVSFVHIL 57

Src Homology 3 domain of Sdc25/Cdc25 guanine nucleotide exchange factors; This subfamily is composed of the Saccharomyces cerevisiae guanine nucleotide exchange factors (GEFs) Sdc25 and Cdc25, and similar proteins. These GEFs regulate Ras by stimulating the GDP/GTP exchange on Ras. Cdc25 is involved in the Ras/PKA pathway that plays an important role in the regulation of metabolism, stress responses, and proliferation, depending on available nutrients and conditions. Proteins in this subfamily contain an N-terminal SH3 domain as well as REM (Ras exchanger motif) and RasGEF domains at the C-terminus. 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 1934025863 761 VETLHDFEAANSDELTLQRGDVVLVVPSDseadqDAGWLVGVKESDWLQYRdlatyKGLFPENF 824
Cdd:cd11883     2 VVALYDFTPKSKNQLSFKAGDIIYVLNKD-----PSGWWDGVIISSSGKVK-----RGWFPSNY 55

Src homology 3 domain of Protein kinase C and Casein kinase Substrate in Neurons (PACSIN) proteins; PACSINs, also called Synaptic dynamin-associated proteins (Syndapins), act as regulators of cytoskeletal and membrane dynamics. They bind both dynamin and Wiskott-Aldrich syndrome protein (WASP), and may provide direct links between the actin cytoskeletal machinery through WASP and dynamin-dependent endocytosis. Vetebrates harbor three isoforms with distinct expression patterns and specific functions. PACSINs contain 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 1934025863 761 VETLHDFEAANSDELTLQRGDVVLVVpsdSEADqDAGWLVGVKESDwlqyrdlatyKGLFPENF 824
Cdd:cd11843     2 VRALYDYEGQESDELSFKAGDILTKL---EEED-EQGWCKGRLDGR----------VGLYPANY 51

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 1934025863 764 LHDFEAANSDELTLQRGDVVLVVpSDSeadqdagwlvgvkESDWLQYRDLAT-YKGLFPENF 824
Cdd:cd11845     5 LYDYEARTDDDLSFKKGDRLQIL-DDS-------------DGDWWLARHLSTgKEGYIPSNY 52