The LIM domain of LIM and SH3 Protein (LASP); The LIM domain of LIM and SH3 Protein (LASP): LASP family contains two highly homologous members, LASP-1 and LASP-2. LASP contains a LIM motif at its amino terminus, a src homology 3 (SH3) domains at its C-terminal part, and a nebulin-like region in the middle. LASP-1 and -2 are highly conserved in their LIM, nebulin-like, and SH3 domains ,but differ significantly at their linker regions. Both proteins are ubiquitously expressed and involved in cytoskeletal architecture, especially in the organization of focal adhesions. LASP-1 and LASP-2, are important during early embryo- and fetogenesis and are highly expressed in the central nervous system of the adult. However, only LASP-1 seems to participate significantly in neuronal differentiation and plays an important functional role in migration and proliferation of certain cancer cells while the role of LASP-2 is more structural. The expression of LASP-1 in breast tumors is increased significantly. As in other LIM domains, this domain family is 50-60 amino acids in size and shares two characteristic zinc finger motifs. The two zinc fingers contain eight conserved residues, mostly cysteines and histidines, which coordinately bond to two zinc atoms. LIM domains function as adaptors or scaffolds to support the assembly of multimeric protein.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|...
gi 47087157   5 CARCGKVVYPTEKVNCLDKYWHKGCFHCEVCKMALNMNNYKGYEKKPYCNAHY 57
Cdd:cd09447   1 CARCGKTVYPTEKLNCLDKIWHKGCFKCEVCGMTLNMKNYKGYNKKPYCNAHY 53

Nebulin repeat;

                          10        20
                  ....*....|....*....|....*...
gi 47087157    67 DTPENLRLKQQSELQSQVKYKRDFEESK 94
Cdd:pfam00880   1 DTPEIVHAKKNAKLQSDVKYKEDYEKEK 28

The LIM domain of LIM and SH3 Protein (LASP); The LIM domain of LIM and SH3 Protein (LASP): LASP family contains two highly homologous members, LASP-1 and LASP-2. LASP contains a LIM motif at its amino terminus, a src homology 3 (SH3) domains at its C-terminal part, and a nebulin-like region in the middle. LASP-1 and -2 are highly conserved in their LIM, nebulin-like, and SH3 domains ,but differ significantly at their linker regions. Both proteins are ubiquitously expressed and involved in cytoskeletal architecture, especially in the organization of focal adhesions. LASP-1 and LASP-2, are important during early embryo- and fetogenesis and are highly expressed in the central nervous system of the adult. However, only LASP-1 seems to participate significantly in neuronal differentiation and plays an important functional role in migration and proliferation of certain cancer cells while the role of LASP-2 is more structural. The expression of LASP-1 in breast tumors is increased significantly. As in other LIM domains, this domain family is 50-60 amino acids in size and shares two characteristic zinc finger motifs. The two zinc fingers contain eight conserved residues, mostly cysteines and histidines, which coordinately bond to two zinc atoms. LIM domains function as adaptors or scaffolds to support the assembly of multimeric protein.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|...
gi 47087157   5 CARCGKVVYPTEKVNCLDKYWHKGCFHCEVCKMALNMNNYKGYEKKPYCNAHY 57
Cdd:cd09447   1 CARCGKTVYPTEKLNCLDKIWHKGCFKCEVCGMTLNMKNYKGYNKKPYCNAHY 53

Variant SH3 domain;

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|.
gi 47087157   217 AMYDYSAQDEDEVSFRDGDYIVNVQPIDDGWMYGtvQRTGRTGMLPANYIE 267
Cdd:pfam14604   1 ALYPYEPKDDDELSLQRGDVITVIEESEDGWWEG--INTGRTGLVPANYVE 49

LIM domain; This family represents two copies of the LIM structural domain.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|...
gi 47087157     5 CARCGKVVYPTEKVNCLDKYWHKGCFHCEVCKMALNMNNYKGYEKKPYCNAHY 57
Cdd:pfam00412   1 CAGCNRPIYDRELVRALGKVWHPECFRCAVCGKPLTTGDFYEKDGKLYCKHDY 53

Nebulin repeat;

                          10        20
                  ....*....|....*....|....*...
gi 47087157   103 DTPELQRLKRTQEQISNVKYHEDFEKTK 130
Cdd:pfam00880   1 DTPEIVHAKKNAKLQSDVKYKEDYEKEK 28

The Nebulin repeat is present also in Las1; Tandem arrays of these repeats are known to bind actin.

                           10        20        30
                   ....*....|....*....|....*....|.
gi 47087157     62 FTTVADTPENLRLKQQSELQSQVKYKRDFEE 92
Cdd:smart00227   1 YTSVPDTPEILLAKKNQKLISDVKYKEDYEK 31

The LIM domain of LIM and SH3 Protein (LASP); The LIM domain of LIM and SH3 Protein (LASP): LASP family contains two highly homologous members, LASP-1 and LASP-2. LASP contains a LIM motif at its amino terminus, a src homology 3 (SH3) domains at its C-terminal part, and a nebulin-like region in the middle. LASP-1 and -2 are highly conserved in their LIM, nebulin-like, and SH3 domains ,but differ significantly at their linker regions. Both proteins are ubiquitously expressed and involved in cytoskeletal architecture, especially in the organization of focal adhesions. LASP-1 and LASP-2, are important during early embryo- and fetogenesis and are highly expressed in the central nervous system of the adult. However, only LASP-1 seems to participate significantly in neuronal differentiation and plays an important functional role in migration and proliferation of certain cancer cells while the role of LASP-2 is more structural. The expression of LASP-1 in breast tumors is increased significantly. As in other LIM domains, this domain family is 50-60 amino acids in size and shares two characteristic zinc finger motifs. The two zinc fingers contain eight conserved residues, mostly cysteines and histidines, which coordinately bond to two zinc atoms. LIM domains function as adaptors or scaffolds to support the assembly of multimeric protein.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|...
gi 47087157   5 CARCGKVVYPTEKVNCLDKYWHKGCFHCEVCKMALNMNNYKGYEKKPYCNAHY 57
Cdd:cd09447   1 CARCGKTVYPTEKLNCLDKIWHKGCFKCEVCGMTLNMKNYKGYNKKPYCNAHY 53

The LIM domain of LIM and SH3 Protein (LASP)-like proteins; The LIM domain of LIM and SH3 Protein (LASP) like proteins: This family contains two types of LIM containing proteins; LASP and N-RAP. LASP family contains two highly homologous members, LASP-1 and LASP-2. LASP contains a LIM motif at its amino terminus, a src homology 3 (SH3) domains at its C-terminal part, and a nebulin-like region in the middle. LASP-1 and -2 are highly conserved in their LIM, nebulin-like, and SH3 domains, but differ significantly at their linker regions. Both proteins are ubiquitously expressed and involved in cytoskeletal architecture, especially in the organization of focal adhesions. LASP-1 and LASP-2, are important during early embryo- and fetogenesis and are highly expressed in the central nervous system of the adult. However, only LASP-1 seems to participate significantly in neuronal differentiation and plays an important functional role in migration and proliferation of certain cancer cells while the role of LASP-2 is more structural. The expression of LASP-1 in breast tumors is increased significantly. N-RAP is a muscle-specific protein concentrated at myotendinous junctions in skeletal muscle and intercalated disks in cardiac muscle. LIM domain is found at the N-terminus of N-RAP and the C-terminal of N-RAP contains a region with multiple of nebulin repeats. N-RAP functions as a scaffolding protein that organizes alpha-actinin and actin into symmetrical I-Z-I structures in developing myofibrils. Nebulin repeat is known as actin binding domain. The N-RAP is hypothesized to form antiparallel dimerization via its LIM domain. As in other LIM domains, this domain family is 50-60 amino acids in size and shares two characteristic zinc finger motifs. The two zinc fingers contain eight conserved residues, mostly cysteines and histidines, which coordinately bond to two zinc atoms. LIM domains function as adaptors or scaffolds to support the assembly of multimeric protein.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|...
gi 47087157   5 CARCGKVVYPTEKVNCLDKYWHKGCFHCEVCKMALNMNNYKGYEKKPYCNAHY 57
Cdd:cd09359   1 CARCGKIVYPTEKVNCLDKTWHKACFHCEVCKMTLNMNNYKGYQKKPYCNAHY 53

C-terminal Src Homology 3 domain of LIM and SH3 domain protein 1; Lasp1 is a cytoplasmic protein that binds focal adhesion proteins and is involved in cell signaling, migration, and proliferation. It is overexpressed in several cancer cells including breast, ovarian, bladder, and liver. In cancer cells, it can be found in the nucleus; its degree of nuclear localization correlates with tumor size and poor prognosis. Lasp1 is a 36kD protein containing an N-terminal LIM domain, two nebulin 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
                ....*....|....*....|....*....|....*....|....*....|....*
gi 47087157 213 RTYRAMYDYSAQDEDEVSFRDGDYIVNVQPIDDGWMYGTVQRTGRTGMLPANYIE 267
Cdd:cd11934   3 KRYRAVYDYNAADEDEVSFQDGDTIVNVQQIDDGWMYGTVERTGDTGMLPANYVE 57

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 47087157    213 RTYRAMYDYSAQDEDEVSFRDGDYIVNVQPIDDGWMYGTVQRtGRTGMLPANYIE 267
Cdd:smart00326   3 PQVRALYDYTAQDPDELSFKKGDIITVLEKSDDGWWKGRLGR-GKEGLFPSNYVE 56

Src homology 3 domain of Cortactin and related proteins; This subfamily includes cortactin, Abp1 (actin-binding protein 1), hematopoietic lineage cell-specific protein 1 (HS1), and similar proteins. These proteins are involved in regulating actin dynamics through direct or indirect interaction with the Arp2/3 complex, which is required to initiate actin polymerization. They all contain at least one C-terminal SH3 domain. Cortactin and HS1 bind Arp2/3 and actin through an N-terminal region that contains an acidic domain and several copies of a repeat domain found in cortactin and HS1. Abp1 binds actin via an N-terminal actin-depolymerizing factor (ADF) homology domain. Yeast Abp1 binds Arp2/3 directly through two acidic domains. Mammalian Abp1 does not directly interact with Arp2/3; instead, it regulates actin dynamics indirectly by interacting with dynamin and WASP family proteins. The C-terminal region of these proteins acts as an adaptor or scaffold that can connect membrane trafficking and signaling proteins that bind the SH3 domain within the actin network. 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 47087157 216 RAMYDYSAQDEDEVSFRDGDYIVNVQPIDDGWMYGtVQRTGRTGMLPANYIE 267
Cdd:cd11819   3 KALYDYQAAEDNEISFVEGDIITQIEQIDEGWWLG-VNAKGQKGLFPANYVE 53

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
                ....*....|....*....|....*....|....*....|....*....|..
gi 47087157 214 TYRAMYDYSAQDEDEVSFRDGDYIVNVQPIDDGWMYGTVQRtGRTGMLPANY 265
Cdd:cd00174   1 YARALYDYEAQDDDELSFKKGDIITVLEKDDDGWWEGELNG-GREGLFPANY 51

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        60
                ....*....|....*....|....*....|....*....|....*....|....*....|
gi 47087157 214 TYRAMYDYSAQDEDEVSFRDGDYIVnVQPID-----DGWMYGTVQRTGRTGMLPANYIEF 268
Cdd:cd11791   1 VLRVLYPYTPQEEDELELVPGDYIY-VSPEEldsssDGWVEGTSWLTGCSGLLPENYTEK 59

Third (or C-terminal) Src Homology 3 domain of Sorbin and SH3 domain containing (Sorbs) proteins and similar domains; This family, also called the vinexin family, is composed predominantly of adaptor proteins containing one sorbin homology (SoHo) and three SH3 domains. Members include the third SH3 domains of Sorbs1 (or ponsin), Sorbs2 (or ArgBP2), Vinexin (or Sorbs3), and similar domains. They are involved in the regulation of cytoskeletal organization, cell adhesion, and growth factor signaling. Members of this family bind multiple partners including signaling molecules like c-Abl, c-Arg, Sos, and c-Cbl, as well as cytoskeletal molecules such as vinculin and afadin. They may have overlapping functions. 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 47087157 215 YRAMYDYSAQDEDEVSFRDGDYIVNVQPIDDGWMYGTVQRTGRTGMLPANYIE 267
Cdd:cd11780   2 YRALYSYTPQNEDELELREGDIVYVMEKCDDGWFVGTSERTGLFGTFPGNYVA 54

Src homology 3 domain of Cortactin; Cortactin was originally identified as a substrate of Src kinase. It is an actin regulatory protein that binds to the Arp2/3 complex and stabilizes branched actin filaments. It is involved in cellular processes that affect cell motility, adhesion, migration, endocytosis, and invasion. It is expressed ubiquitously except in hematopoietic cells, where the homolog hematopoietic lineage cell-specific 1 (HS1) is expressed instead. Cortactin contains an N-terminal acidic domain, several copies of a repeat domain found in cortactin and HS1, a proline-rich region, and a C-terminal SH3 domain. The N-terminal region interacts with the Arp2/3 complex and F-actin, and is crucial in regulating branched actin assembly. Cortactin also serves as a scaffold and provides a bridge to the actin cytoskeleton for membrane trafficking and signaling proteins that bind to its SH3 domain. Binding partners for the SH3 domain of cortactin include dynamin2, N-WASp, MIM, FGD1, 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 47087157 217 AMYDYSAQDEDEVSFRDGDYIVNVQPIDDGWMYGTVQrtGRTGMLPANYIE 267
Cdd:cd11959   4 ALYDYQAADDDEISFDPDDIITNIEMIDEGWWRGVCR--GKYGLFPANYVE 52

Second C-terminal Src homology 3 domain of Fungal Actin-binding protein 1; Abp1 is an adaptor protein that functions in receptor-mediated endocytosis and vesicle trafficking. It contains an N-terminal actin-binding module, the actin-depolymerizing factor (ADF) homology domain, a central proline-rich region, and a C-terminal SH3 domain (many yeast Abp1 proteins contain two C-terminal SH3 domains). Yeast Abp1 also contains two acidic domains that bind directly to the Arp2/3 complex, which is required to initiate actin polymerization. The SH3 domain of yeast Abp1 binds and localizes the kinases, Ark1p and Prk1p, which facilitate actin patch disassembly following vesicle internalization. It also mediates the localization to the actin patch of the synaptojanin-like protein, Sjl2p, which plays a key role in endocytosis. 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 47087157 214 TYRAMYDYSAQDEDEVSFRDGDYIVNVQPIDDGWMYGTVQrtGRTGMLPANYIE 267
Cdd:cd11961   1 WAKALYDYDAAEDNELSFFENDKIINIEFVDDDWWLGECH--GSRGLFPSNYVE 52

The LIM domains of thymus LIM protein (TLP); The LIM domain of thymus LIM protein (TLP) like proteins: This family includes the LIM domains of TLP and CRIP (Cysteine-Rich Intestinal Protein). TLP is the distant member of the CRP family of proteins. TLP has two isomers (TLP-A and TLP-B) and sharing approximately 30% with each of the three other CRPs. Like CRP1, CRP2 and CRP3/MLP, TLP has two LIM domains, connected by a flexible linker region. Unlike the CRPs, TLP lacks the nuclear targeting signal (K/R-K/R-Y-G-P-K) and is localized solely in the cytoplasm. TLP is specifically expressed in the thymus in a subset of cortical epithelial cells. TLP has a role in development of normal thymus and in controlling the development and differentiation of thymic epithelial cells. CRIP is a short LIM protein with only one LIM domain. CRIP gene is developmentally regulated and can be induced by glucocorticoid hormones during the first three postnatal weeks. The domain shows close sequence homology to LIM domain of thymus LIM protein. However, unlike the TLP proteins which have two LIM domains, the members of this family have only one LIM domain. LIM domains are 50-60 amino acids in size and share two characteristic zinc finger motifs. The two zinc fingers contain eight conserved residues, mostly cysteines and histidines, which coordinately bond to two zinc atoms. LIM domains function as adaptors or scaffolds to support the assembly of multimeric protein complexes.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|...
gi 47087157   5 CARCGKVVYPTEKVNCLDKYWHKGCFHCEVCKMALNMNNYKGYEKKPYCNAHY 57
Cdd:cd09401   1 CPKCGKPVYFAEKKTSLGRDWHKPCLRCEKCKKTLTPGQHSEHEGKPYCNKCY 53

LIM domain; This family represents two copies of the LIM structural domain.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|...
gi 47087157     5 CARCGKVVYPTEKVNCLDKYWHKGCFHCEVCKMALNMNNYKGYEKKPYCNAHY 57
Cdd:pfam00412   1 CAGCNRPIYDRELVRALGKVWHPECFRCAVCGKPLTTGDFYEKDGKLYCKHDY 53

The LIM domains of Cysteine Rich Protein (CRP) family; The LIM domains of Cysteine Rich Protein (CRP) family: Cysteine-rich proteins (CRPs) are characterized by the presence of two LIM domains linked to a short glycine-rich repeats (GRRs). The known CRP family members include CRP1, CRP2, and CRP3/MLP. CRP1, CRP2 and CRP3 share a conserved nuclear targeting signal (K/R-K/R-Y-G-P-K), which supports the fact that these proteins function not only in the cytoplasm but also in the nucleus. CRPs control regulatory pathways during cellular differentiation, and involve in complex transcription control, and the organization as well as the arrangement of the myofibrillar/cytoskeletal network. CRP1, CRP2, and CRP3/MLP are involved in promoting protein assembly along the actin-based cytoskeleton. All LIM domains are 50-60 amino acids in size and share two characteristic zinc finger motifs. The two zinc fingers contain eight conserved residues, mostly cysteines and histidines, which coordinately bond to two zinc atoms. LIM domains function as adaptors or scaffolds to support the assembly of multimeric protein complexes.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|...
gi 47087157   5 CARCGKVVYPTEKVNCLDKYWHKGCFHCEVCKMALNMNNYKGYEKKPYCNAHY 57
Cdd:cd09326   1 CPRCGKSVYAAEEVIAAGKSWHKSCFTCAVCNKRLDSTTLAEHDGEIYCKSCY 53

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.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|...
gi 47087157 216 RAMYDYSAQDEDEVSFRDGDYIVNVQPIDD-GWMYGtvQRTGRTGMLPANYIE 267
Cdd:cd11843   3 RALYDYEGQESDELSFKAGDILTKLEEEDEqGWCKG--RLDGRVGLYPANYVE 53

Src homology 3 domain of an unknown subfamily of proteins with similarity to 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.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|...
gi 47087157 216 RAMYDYSAQDEDEVSFRDGDYIVNVQPIDD-GWMYGtVQRTGRTGMLPANYIE 267
Cdd:cd11999   5 RAVYDYTGQEPDELSFKAGEELLKVEDEDEqGWCKG-VTDGGAVGLYPANYVE 56

Src homology 3 domain of Hematopoietic lineage cell-specific protein 1; HS1, also called HCLS1 (hematopoietic cell-specific Lyn substrate 1), is a cortactin homolog expressed specifically in hematopoietic cells. It is an actin regulatory protein that binds the Arp2/3 complex and stabilizes branched actin filaments. It is required for cell spreading and signaling in lymphocytes. It regulates cytoskeletal remodeling that controls lymphocyte trafficking, and it also affects tissue invasion and infiltration of leukemic B cells. Like cortactin, HS1 contains an N-terminal acidic domain, several copies of a repeat domain found in cortactin and HS1, a proline-rich region, and a C-terminal SH3 domain. The N-terminal region binds the Arp2/3 complex and F-actin, while the C-terminal region acts as an adaptor or scaffold that can connect varied proteins that bind the SH3 domain within the actin network. 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 47087157 217 AMYDYSAQDEDEVSFRDGDYIVNVQPIDDGWMYGTVQrtGRTGMLPANYIEF 268
Cdd:cd12073   5 ALYDYQGEGDDEISFDPQETITDIEMVDEGWWKGTCH--GHRGLFPANYVEL 54

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
                ....*....|....*....|....*....|....*....|....*....|....
gi 47087157 214 TYRAMYDYSAQDEDEVSFRDGDYIVNVQPIDDGWMYGTVQrtGRTGMLPANYIE 267
Cdd:cd11877   1 LVRAKFNFEGTNEDELSFDKGDIITVTQVVEGGWWEGTLN--GKTGWFPSNYVK 52

Src homology 3 domain of Protein kinase C and Casein kinase Substrate in Neurons 3 (PACSIN3); PACSIN 3 or Syndapin III (Synaptic dynamin-associated protein III) is expressed ubiquitously and regulates glucose uptake in adipocytes through its role in GLUT1 trafficking. It also modulates the subcellular localization and stimulus-specific function of the cation channel TRPV4. PACSINs act as regulators of cytoskeletal and membrane dynamics. 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.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|...
gi 47087157 216 RAMYDYSAQDEDEVSFRDGDYIVNVQPIDD-GWMYGTVQrTGRTGMLPANYIE 267
Cdd:cd11997   5 RALYDYTGQEADELSFKAGEELLKIGEEDEqGWCKGRLL-SGRIGLYPANYVE 56

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.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|..
gi 47087157 216 RAMYDYSAQDEDEVSFRDGDYIVNVQPIDDGWMYGTVQrtGRTGMLPANYIE 267
Cdd:cd11823   3 KALYSYTANREDELSLQPGDIIEVHEKQDDGWWLGELN--GKKGIFPATYVE 52

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.

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gi 47087157 212 LRTYRAMYDYSAQDEDEVSFRDGDyIVNVQPIDD------GWMYGTVQRTGRTGMLPANYIE 267
Cdd:cd11790   2 LYKVRATHDYTAEDTDELTFEKGD-VILVIPFDDpeeqdeGWLMGVKESTGCRGVFPENFTE 62

Src homology 3 domain of Protein kinase C and Casein kinase Substrate in Neurons 1 (PACSIN1) and PACSIN 2; PACSIN 1 or Syndapin I (Synaptic dynamin-associated protein I) is expressed specifically in the brain and is localized in neurites and synaptic boutons. It binds the brain-specific proteins dynamin I, synaptojanin, synapsin I, and neural Wiskott-Aldrich syndrome protein (nWASP), and functions as a link between the cytoskeletal machinery and synaptic vesicle endocytosis. PACSIN 1 interacts with huntingtin and may be implicated in the neuropathology of Huntington's disease. PACSIN 2 or Syndapin II is expressed ubiquitously and is involved in the regulation of tubulin polymerization. It associates with Golgi membranes and forms a complex with dynamin II which is crucial in promoting vesicle formation from the trans-Golgi network. PACSINs act as regulators of cytoskeletal and membrane dynamics. 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 47087157 216 RAMYDYSAQDEDEVSFRDGDYIVNVQPIDD-GWMYGTVQrTGRTGMLPANYIE 267
Cdd:cd11998   4 RALYDYDGQEQDELSFKAGDELTKLEDEDEqGWCKGRLD-SGQVGLYPANYVE 55

Third (or C-terminal) Src Homology 3 domain of Sorbin and SH3 domain containing 2 (Sorbs2), also called Arg-binding protein 2 (ArgBP2); Sorbs2 or ArgBP2 is an adaptor protein containing one sorbin homology (SoHo) and three SH3 domains. It regulates actin-dependent processes including cell adhesion, morphology, and migration. It is expressed in many tissues and is abundant in the heart. Like vinexin, it is found in focal adhesion where it interacts with vinculin and afadin. It also localizes in epithelial cell stress fibers and in cardiac muscle cell Z-discs. Sorbs2 has been implicated to play roles in the signaling of c-Arg, Akt, and Pyk2. Other interaction partners of Sorbs2 include c-Abl, flotillin, spectrin, dynamin 1/2, synaptojanin, PTP-PEST, 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 47087157 215 YRAMYDYSAQDEDEVSFRDGDYIVNVQPIDDGWMYGTVQRTGRTGMLPANYIE 267
Cdd:cd11917   7 FQALYNYMPRNEDELELREGDVIDVMEKCDDGWFVGTSRRTKFFGTFPGNYVK 59

The first LIM domain of Cysteine Rich Protein 3 (CRP3/MLP); The first LIM domain of Cysteine Rich Protein 3 (CRP3/MLP): Cysteine-rich proteins (CRPs) are characterized by the presence of two LIM domains linked to short glycine-rich repeats (GRRs). The CRP family members include CRP1, CRP2, CRP3/MLP and TLPCRP1, CRP2 and CRP3 share a conserved nuclear targeting signal (K/R-K/R-Y-G-P-K), which supports the fact that these proteins function not only in the cytoplasm but also in the nucleus. CRPs control regulatory pathways during cellular differentiation, and involve in complex transcription circuits, and the organization as well as the arrangement of the myofibrillar/cytoskeletal network.CRP3 also called Muscle LIM Protein (MLP), which is a striated muscle-specific factor that enhances myogenic differentiation. CRP3/MLP interacts with cytoskeletal protein beta-spectrin. CRP3/MLP also interacts with the basic helix-loop-helix myogenic transcriptio n factors MyoD, myogenin, and MRF4 thereby increasing their affinity for specific DNA regulatory elements. LIM domains are 50-60 amino acids in size and share two characteristic zinc finger motifs. The two zinc fingers contain eight conserved residues, mostly cysteines and histidines, which coordinately bond to two zinc atoms. LIM domains function as adaptors or scaffolds to support the assembly of multimeric protein complexes.

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gi 47087157   4 QCARCGKVVYPTEKVNCLDKYWHKGCFHCEVCKMALNMNNYKGYEKKPYCNAHY 57
Cdd:cd09481   1 KCGACEKTVYHAEEIQCNGRSFHKTCFICMACRKALDSTTVAAHESEIYCKTCY 54

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

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gi 47087157   216 RAMYDYSAQDEDEVSFRDGDYIVNVQPIDDGWMYGTVqRTGRTGMLPA 263
Cdd:pfam00018   1 VALYDYTAQEPDELSFKKGDIIIVLEKSEDGWWKGRN-KGGKEGLIPS 47

Src homology 3 domain of Myosins Ie, If, and similar proteins; Myosins Ie (MyoIe) and If (MyoIf) are nonmuscle, unconventional, long tailed, class I myosins containing an N-terminal motor domain and a myosin tail with TH1, TH2, and SH3 domains. MyoIe interacts with the endocytic proteins, dynamin and synaptojanin-1, through its SH3 domain; it may play a role in clathrin-dependent endocytosis. In the kidney, MyoIe is critical for podocyte function and normal glomerular filtration. Mutations in MyoIe is associated with focal segmental glomerulosclerosis, a disease characterized by massive proteinuria and progression to end-stage kidney disease. MyoIf is predominantly expressed in the immune system; it plays a role in immune cell motility and innate immunity. Mutations in MyoIf may be associated with the loss of hearing. The MyoIf gene has also been found to be fused to the MLL (Mixed lineage leukemia) gene in infant acute myeloid leukemias (AML). 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 47087157 216 RAMYDYSAQDEDEVSFRDGDYIVNVQPIDDGWMYGTVQrtGRTGMLPANYIE 267
Cdd:cd11827   3 KALYAYDAQDTDELSFNEGDIIEILKEDPSGWWTGRLR--GKEGLFPGNYVE 52

C-terminal Src homology 3 domain of Growth factor receptor-bound protein 2 (GRB2) and related proteins; This family includes the adaptor protein GRB2 and related proteins including Drosophila melanogaster Downstream of receptor kinase (DRK), Caenorhabditis elegans Sex muscle abnormal protein 5 (Sem-5), GRB2-related adaptor protein (GRAP), GRAP2, and similar proteins. Family members contain an N-terminal SH3 domain, a central SH2 domain, and a C-terminal SH3 domain. GRB2/Sem-5/DRK is a critical signaling molecule that regulates the Ras pathway by linking tyrosine kinases to the Ras guanine nucleotide releasing protein Sos (son of sevenless), which converts Ras to the active GTP-bound state. GRAP2 plays an important role in T cell receptor (TCR) signaling by promoting the formation of the SLP-76:LAT complex, which couples the TCR to the Ras pathway. GRAP acts as a negative regulator of T cell receptor (TCR)-induced lymphocyte proliferation by downregulating the signaling to the Ras/ERK pathway. The C-terminal SH3 domains (SH3c) of GRB2 and GRAP2 have been shown to bind to classical PxxP motif ligands, as well as to non-classical motifs. GRB2 SH3c binds Gab2 (Grb2-associated binder 2) through epitopes containing RxxK motifs, while the SH3c of GRAP2 binds to the phosphatase-like protein HD-PTP via a RxxxxK motif. SH3 domains are protein interaction domains that typically 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 47087157 216 RAMYDYSAQDEDEVSFRDGDYIVNVQPIDDGWMYGTVQrtGRTGMLPANYIE 267
Cdd:cd11805   3 QALYDFNPQEPGELEFRRGDIITVLDSSDPDWWKGELR--GRVGIFPANYVQ 52

First C-terminal Src homology 3 domain of Fungal Actin-binding protein 1; Abp1 is an adaptor protein that functions in receptor-mediated endocytosis and vesicle trafficking. It contains an N-terminal actin-binding module, the actin-depolymerizing factor (ADF) homology domain, a central proline-rich region, and a C-terminal SH3 domain (many yeast Abp1 proteins contain two C-terminal SH3 domains). Yeast Abp1 also contains two acidic domains that bind directly to the Arp2/3 complex, which is required to initiate actin polymerization. The SH3 domain of yeast Abp1 binds and localizes the kinases, Ark1p and Prk1p, which facilitate actin patch disassembly following vesicle internalization. It also mediates the localization to the actin patch of the synaptojanin-like protein, Sjl2p, which plays a key role in endocytosis. 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 47087157 219 YDYSAQDEDEVSFRDGDYIVNVQPIDDGWMYGTVQRtGRTGMLPANYIE 267
Cdd:cd11962   6 YDYEKDEDNEIELVEGEIVTNIEMVDEDWWMGTNSK-GESGLFPSNYVE 53

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.

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gi 47087157 213 RTYRAMYDYSAQDEDEVSFRDGDYIVnVQP-----IDDGWMYGTVQRTGRTGMLPANYIE 267
Cdd:cd11937   1 QTLRALFQYKPQNIDELMLSPGDYIF-VDPtqqseASEGWVIGISHRTGCRGFLPENYTE 59

Second Src Homology 3 domain of Nck adaptor proteins; Nck adaptor proteins regulate actin cytoskeleton dynamics by linking proline-rich effector molecules to protein tyrosine kinases and phosphorylated signaling intermediates. They contain three SH3 domains and a C-terminal SH2 domain. They function downstream of the PDGFbeta receptor and are involved in Rho GTPase signaling and actin dynamics. Vertebrates contain two Nck adaptor proteins: Nck1 (also called Nckalpha) and Nck2 (also called Nckbeta or Growth factor receptor-bound protein 4, Grb4), which show partly overlapping functions but also bind distinct targets. Their SH3 domains are involved in recruiting downstream effector molecules, such as the N-WASP/Arp2/3 complex, which when activated induces actin polymerization that results in the production of pedestals, or protrusions of the plasma membrane. The second SH3 domain of Nck appears to prefer ligands containing the APxxPxR motif. SH3 domains are protein interaction domains that usually bind to proline-rich ligands with moderate affinity and selectivity, preferentially a PxxP motif. 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 47087157 214 TYRAMYDYSAQDEDEVSFRDGDYIVNVQPIDDGWMYGTVQrtGRTGMLPANYIE 267
Cdd:cd11766   1 PAVVKFNYEAQREDELSLRKGDRVLVLEKSSDGWWRGECN--GQVGWFPSNYVT 52

Third Src Homology 3 domain of the fungal endocytic adaptor protein Sla1p; Sla1p facilitates endocytosis by playing a role as an adaptor protein in coupling components of the actin cytoskeleton to the endocytic machinery. It interacts with Abp1p, Las17p and Pan1p, which are activator proteins of actin-related protein 2/3 (Arp2/3). Sla1p contains multiple domains including three SH3 domains, a SAM (sterile alpha motif) domain, and a Sla1 homology domain 1 (SHD1), which binds to the NPFXD motif that is found in many integral membrane proteins such as the Golgi-localized Arf-binding protein Lsb5p and the P4-ATPases, Drs2p and Dnf1p. The third SH3 domain of Sla1p can bind ubiquitin while retaining the ability to bind proline-rich ligands; monoubiquitination of target proteins signals internalization and sorting through the endocytic pathway. 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 47087157 216 RAMYDYSAQDEDEVSFRDGD--YIVNVQPIDDGWMygtVQR--TGRTGMLPANYIE 267
Cdd:cd11775   4 KVLYDFDAQSDDELTVKEGDvvYILDDKKSKDWWM---VENvsTGKEGVVPASYIE 56

Src homology 3 domains of the p47phox subunit of NADPH oxidase and similar domains; This family is composed of the tandem SH3 domains of p47phox subunit of NADPH oxidase and Nox Organizing protein 1 (NoxO1), the four SH3 domains of Tks4 (Tyr kinase substrate with four SH3 domains), the five SH3 domains of Tks5, the SH3 domain of obscurin, Myosin-I, and similar domains. Most members of this group also contain Phox homology (PX) domains, except for obscurin and Myosin-I. p47phox and NoxO1 are regulators of the phagocytic NADPH oxidase complex (also called Nox2 or gp91phox) and nonphagocytic NADPH oxidase Nox1, respectively. They play roles in the activation of their respective NADPH oxidase, which catalyzes the transfer of electrons from NADPH to molecular oxygen to form superoxide. Tks proteins are Src substrates and scaffolding proteins that play important roles in the formation of podosomes and invadopodia, the dynamic actin-rich structures that are related to cell migration and cancer cell invasion. Obscurin is a giant muscle protein that plays important roles in the organization and assembly of the myofibril and the sarcoplasmic reticulum. Type I myosins (Myosin-I) are actin-dependent motors in endocytic actin structures and actin patches. They play roles in membrane traffic in endocytic and secretory pathways, cell motility, and mechanosensing. Myosin-I contains an N-terminal actin-activated ATPase, a phospholipid-binding TH1 (tail homology 1) domain, and a C-terminal extension which includes an F-actin-binding TH2 domain, an SH3 domain, and an acidic peptide that participates in activating the Arp2/3complex. The SH3 domain of myosin-I is required for myosin-I-induced actin polymerization. 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 47087157 214 TYRAMYDYSAQDEDEVSFRDGDYIVNVQPIDDGWMYgtVQRTGRTGMLPANYIE 267
Cdd:cd11856   1 SYVAIADYEAQGDDEISLQEGEVVEVLEKNDSGWWY--VRKGDKEGWVPASYLE 52

Src Homology 3 domain of eumetazoan Peroxisomal biogenesis factor 13; PEX13 is a peroxin and is required for protein import into the peroxisomal matrix and membrane. It is an integral membrane protein that is essential for the localization of PEX14 and the import of proteins containing the peroxisome matrix targeting signals, PTS1 and PTS2. Mutations of the PEX13 gene in humans lead to a wide range of peroxisome biogenesis disorders (PBDs), the most severe of which is known as Zellweger syndrome (ZS), a severe multisystem disorder characterized by hypotonia, psychomotor retardation, and neuronal migration defects. PEX13 contains two transmembrane regions 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 47087157 216 RAMYDYSAQDEDEVSFRDGDyIVNV-----QPIDDGWMYGTVQRTgRTGMLPANYIE 267
Cdd:cd11864   3 RAEYDFVAESEDELSFRAGD-KLRLapkelQPRVRGWLLATVDGQ-KIGLVPANYVK 57

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.

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gi 47087157 215 YRAMYDYSAQDEDEVSFRDGDyIVNVQPI------DDGWMYGTVQRtgRTGMLPANYI 266
Cdd:cd12058   2 WTALYDYEASGEDELSLRRGD-VVEVLSQdaavsgDDGWWAGKIRH--RLGIFPANYV 56

Src homology 3 domain of Phospholipase C (PLC) gamma; PLC catalyzes the hydrolysis of phosphatidylinositol (4,5)-bisphosphate [PtdIns(4,5)P2] to produce Ins(1,4,5)P3 and diacylglycerol (DAG) in response to various receptors. Ins(1,4,5)P3 initiates the calcium signaling cascade while DAG functions as an activator of PKC. PLCgamma catalyzes this reaction in tyrosine kinase-dependent signaling pathways. It is activated and recruited to its substrate at the membrane. Vertebrates contain two forms of PLCgamma, PLCgamma1, which is widely expressed, and PLCgamma2, which is primarily found in haematopoietic cells. PLCgamma contains a Pleckstrin homology (PH) domain followed by an elongation factor (EF) domain, two catalytic regions of PLC domains that flank two tandem SH2 domains, followed by a SH3 domain and C2 domain. The SH3 domain of PLCgamma1 directly interacts with dynamin-1 and can serve as a guanine nucleotide exchange factor (GEF). It also interacts with Cbl, inhibiting its phosphorylation and activity. 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 47087157 214 TYRAMYDYSAQDEDEVSFRDGDYIVNVQPIDDGWM---YGtvqrTGRTGMLPANYIE 267
Cdd:cd11825   1 TVKALYDYRAQRPDELSFCKHAIITNVEKEDGGWWrgdYG----GKKQKWFPANYVE 53

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.

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gi 47087157 215 YRAMYDYSAQDEDEVSFRDGDYIVNVQPIDDGWMYGTVQRTGRTGMLPANYI 266
Cdd:cd11926   2 YVAIYPYTPRKEDELELRKGEMFLVFERCQDGWFKGTSMHTSKIGVFPGNYV 53

Fourth Src homology 3 domain of ADAM-binding protein Eve-1; Eve-1, also called SH3 domain-containing protein 19 (SH3D19) or EEN-binding protein (EBP), exists in multiple alternatively spliced isoforms. The longest isoform contains five SH3 domain in the C-terminal region and seven proline-rich motifs in the N-terminal region. It is abundantly expressed in skeletal muscle and heart, and may be involved in regulating the activity of ADAMs (A disintegrin and metalloproteases). Eve-1 interacts with EEN, an endophilin involved in endocytosis and may be the target of the MLL-EEN fusion protein that is implicated in leukemogenesis. 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 47087157 217 AMYDYSAQDEDEVSFRDGDYIVNVQPIDDGWMYGTVQrtGRTGMLPANY 265
Cdd:cd11817   4 ALYDFTGETEEDLSFQRGDRILVTEHLDAEWSRGRLN--GREGIFPRAF 50

Src Homology 3 domain of GTPase Regulator Associated with Focal adhesion kinase 3; GRAF3 is also called Rho GTPase activating protein 42 (ARHGAP42) or ARHGAP10-like. Though its function has not been characterized, it may be a GAP with activity towards RhoA and Cdc42, based on its similarity to GRAF and GRAF2. It contains an N-terminal BAR domain, followed by a Pleckstrin homology (PH) domain, a Rho GAP domain, and a C-terminal SH3 domain. The SH3 domain of GRAF and GRAF2 binds PKNbeta, a target of the small GTPase Rho. 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 47087157 216 RAMYDYSAQDEDEVSFRDGDYIVNVQP-IDDGWMYGTVQrtGRTGMLPANYIEFV 269
Cdd:cd12066   3 KAMYSCKAEHSHELSFPQGAIFSNVYPsVEPGWLKATYE--GKTGLVPENYVVFL 55

The first LIM domain of LIMK (LIM domain Kinase ); The first LIM domain of LIMK (LIM domain Kinase ): LIMK protein family is comprised of two members LIMK1 and LIMK2. LIMK contains two LIM domains, a PDZ domain and a kinase domain. LIMK is involved in the regulation of actin polymerization and microtubule disassembly. LIMK influences architecture of the actin cytoskeleton by regulating the activity of the cofilin family proteins cofilin1, cofilin2, and destrin. The mechanism of the activation is to phosphorylates cofilin on serine 3 and inactivates its actin-severing activity, and altering the rate of actin depolymerisation. LIMKs can function in both cytoplasm and nucleus and are expressed in all tissues. Both LIMK1 and LIMK2 can act in the nucleus to suppress Rac/Cdc42-dependent cyclin D1 expression. However, LIMK1 and LIMk2 have different cellular locations. While LIMK1 localizes mainly at focal adhesions, LIMK2 is found in cytoplasmic punctae, suggesting that they may have different cellular functions. The LIM domains of LIMK have been shown to play an important role in regulating kinase activity and likely also contribute to LIMK function by acting as sites of protein-to-protein interactions. All LIM domains are 50-60 amino acids in size and share two characteristic zinc finger motifs. The two zinc fingers contain eight conserved residues, mostly cysteines and histidines, which coordinately bond to two zinc atoms. LIM domains function as adaptors or scaffolds to support the assembly of multimeric protein complexes.

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gi 47087157   5 CARCGKVVYPTEKVNCLDKYWHKGCFHCEVCKMALNmNNYKGYEKKPYCNAHY 57
Cdd:cd09364   1 CAGCRGKILDSQYVQALNQDWHCDCFRCSVCSDSLS-NWYFEKDGKLYCRKDY 52