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
                ....*....|....*....|....*....|....*....|....*....|....
gi 71985887 271 VKAIYDYAAADKDEISFLEGDIIVNCEKIDDGWMTGTVQRTLQWGMLPANYVQP 324
Cdd:cd11789   2 YRAMYDYAAADDDEVSFQEGDVIINVEIIDDGWMEGTVQRTGQSGMLPANYVEL 55

Nebulin repeat;

                          10        20
                  ....*....|....*....|....*...
gi 71985887    69 DTPEMRRIAENTKNQSNIKYHAEYEKMK 96
Cdd:pfam00880   1 DTPEIVHAKKNAKLQSDVKYKEDYEKEK 28

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
                ....*....|....*....|....*....|....*....|....*....|....
gi 71985887 271 VKAIYDYAAADKDEISFLEGDIIVNCEKIDDGWMTGTVQRTLQWGMLPANYVQP 324
Cdd:cd11789   2 YRAMYDYAAADDDEVSFQEGDVIINVEIIDDGWMEGTVQRTGQSGMLPANYVEL 55

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

                           10        20        30        40        50
                   ....*....|....*....|....*....|....*....|....*....|....*.
gi 71985887    268 GFAVKAIYDYAAADKDEISFLEGDIIVNCEKIDDGWMTGTVQRtLQWGMLPANYVQ 323
Cdd:smart00326   2 GPQVRALYDYTAQDPDELSFKKGDIITVLEKSDDGWWKGRLGR-GKEGLFPSNYVE 56

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

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|....*
gi 71985887     5 CARedCGKTVYPVEELKCLDKVWHKQCFKCTVCGMTLNMKNYKGYDKRPYCDPHY 59
Cdd:pfam00412   1 CAG--CNRPIYDRELVRALGKVWHPECFRCAVCGKPLTTGDFYEKDGKLYCKHDY 53

Nebulin repeat;

                          10        20
                  ....*....|....*....|....*...
gi 71985887    69 DTPEMRRIAENTKNQSNIKYHAEYEKMK 96
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
                   ....*....|....*....|....*...
gi 71985887    102 IADDPEMERLKKNTQVQSNVSYHGVLDQ 129
Cdd:smart00227   4 VPDTPEILLAKKNQKLISDVKYKEDYEK 31

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
                ....*....|....*....|....*....|....*....|....*....|....
gi 71985887 271 VKAIYDYAAADKDEISFLEGDIIVNCEKIDDGWMTGTVQRTLQWGMLPANYVQP 324
Cdd:cd11789   2 YRAMYDYAAADDDEVSFQEGDVIINVEIIDDGWMEGTVQRTGQSGMLPANYVEL 55

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 71985887 267 AGFAVKAIYDYAAADKDEISFLEGDIIVNCEKIDDGWMTGTVQRTLQWGMLPANYVQ 323
Cdd:cd11934   1 GGKRYRAVYDYNAADEDEVSFQDGDTIVNVQQIDDGWMYGTVERTGDTGMLPANYVE 57

C-terminal Src Homology 3 domain of Nebulin; Nebulin is a giant filamentous protein (600-900 kD) that is expressed abundantly in skeletal muscle. It binds to actin thin filaments and regulates its assembly and function. Nebulin was thought to be part of a molecular ruler complex that is critical in determining the lengths of actin thin filaments in skeletal muscle since its length, which varies due to alternative splicing, correlates with the length of thin filaments in various muscle types. Recent studies indicate that nebulin regulates thin filament length by stabilizing the filaments and preventing depolymerization. Mutations in nebulin can cause nemaline myopathy, characterized by muscle weakness which can be severe and can lead to neonatal lethality. Nebulin contains an N-terminal LIM domain, many nebulin repeats/super 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 71985887 268 GFAVKAIYDYAAADKDEISFLEGDIIVNCEKIDDGWMTGTVQRTLQWGMLPANYVQ 323
Cdd:cd11933   1 GKSFRAMYDYRAADDDEVSFKDGDTIVNVQTIDEGWMYGTVQRTGKTGMLPANYVE 56

The LIM domain of Mical (molecule interacting with CasL) like family; The LIM domain of Mical (molecule interacting with CasL) like family: Known members of this family includes LIM domain containing proteins; Mical (molecule interacting with CasL), pollen specific protein SF3, Eplin, xin actin-binding repeat-containing protein 2 (XIRP2) and Ltd-1. The members of this family function mainly at the cytoskeleton and focal adhesions. They interact with transcription factors or other signaling molecules to play roles in muscle development, neuronal differentiation, cell growth and mobility. Eplin has also found to be tumor suppressor. 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 71985887   5 CARedCGKTVYPVEELKCLDKVWHKQCFKCTVCGMTLNMKNYKGYDKRPYCDPHY 59
Cdd:cd09358   1 CAV--CGKTVYPMERLVADGKLFHKSCFRCSHCNKTLRLGNYASLEGKLYCKPHF 53

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 71985887    268 GFAVKAIYDYAAADKDEISFLEGDIIVNCEKIDDGWMTGTVQRtLQWGMLPANYVQ 323
Cdd:smart00326   2 GPQVRALYDYTAQDPDELSFKKGDIITVLEKSDDGWWKGRLGR-GKEGLFPSNYVE 56

Src homology 3 domain of eumetazoan Actin-binding protein 1; Abp1, also called drebrin-like protein, 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 helical domain, and a C-terminal SH3 domain. Mammalian Abp1, unlike yeast Abp1, does not contain an acidic domain that interacts with the Arp2/3 complex. It regulates actin dynamics indirectly by interacting with dynamin and WASP family proteins. Abp1 deficiency causes abnormal organ structure and function of the spleen, heart, and lung of mice. 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 71985887 271 VKAIYDYAAADKDEISFLEGDIIVNCEKIDDGWMTGTVQRTlQWGMLPANYVQ 323
Cdd:cd11960   2 ARALYDYQAADDTEISFDPGDIITDIEQIDEGWWRGTGPDG-TYGLFPANYVE 53

The first Lim domain of pollen specific protein SF3; The first Lim domain of pollen specific protein SF3: SF3 is a Lim protein that is found exclusively in mature plant pollen grains. It contains two LIM domains. The exact function of SF3 is unknown. It may be a transcription factor required for the expression of late pollen genes. It is possible that SF3 protein is involved in controlling pollen-specific processes such as male gamete maturation, pollen tube formation, or even fertilization. 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 71985887   4 KCarEDCGKTVYPVEELKCLDKVWHKQCFKCTVCGMTLNMKNYKGYDKRPYCDPHY 59
Cdd:cd09440   4 KC--KACDKTVYLVDQLSADGVVYHKSCFRCSHCKGTLKLSNYSSMEGVLYCKPHF 57

Zinc-binding domain present in Lin-11, Isl-1, Mec-3; Zinc-binding domain family. Some LIM domains bind protein partners via tyrosine-containing motifs. LIM domains are found in many key regulators of developmental pathways.

                           10        20        30        40        50
                   ....*....|....*....|....*....|....*....|....*....|....*.
gi 71985887      4 KCARedCGKTVYPVEE-LKCLDKVWHKQCFKCTVCGMTLNMKNYKGYDKRPYCDPH 58
Cdd:smart00132   1 KCAG--CGKPIYGTERvLRALGKVWHPECFKCATCGKPLSGDTFFEKDGKLYCKDC 54

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 71985887 272 KAIYDYAAADKDEISFLEGDIIVNCEKIDDGWMTGTVQRTLQWGMLPANYVQP 324
Cdd:cd11780   3 RALYSYTPQNEDELELREGDIVYVMEKCDDGWFVGTSERTGLFGTFPGNYVAR 55

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 71985887 271 VKAIYDYAAADKDEISFLEGDIIVNCEKIDDGWMTGTVQRtlQWGMLPANYVQ 323
Cdd:cd11961   2 AKALYDYDAAEDNELSFFENDKIINIEFVDDDWWLGECHG--SRGLFPSNYVE 52

This domain belongs to the LIM domain family which are found on Mical (molecule interacting with CasL) like proteins; The LIM domain on proteins of unknown function: This domain belongs to the LIM domain family which are found on Mical (molecule interacting with CasL)-like proteins. Known members of the Mical-like family includes single LIM domain containing proteins, Mical (molecule interacting with CasL), pollen specific protein SF3, Eplin, xin actin-binding repeat-containing protein 2 (XIRP2), and Ltd-1. The members of this family function mainly at the cytoskeleton and focal adhesions. They interact with transcription factors or other signaling molecules to play roles in muscle development, neuronal differentiation, cell growth, and mobility. 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 71985887  10 CGKTVYPVEELKCLDKVWHKQCFKCTVCGMTLNMKNYKGYDKRPYCDPHY 59
Cdd:cd09445   4 CGKPVYKMEEIIAEKHIYHKNCFRCKDCNKQLKVDNYQSHEGNLYCKVHF 53

LIM is a small protein-protein interaction domain, containing two zinc fingers; LIM domains are identified in a diverse group of proteins with wide variety of biological functions, including gene expression regulation, cell fate determination, cytoskeleton organization, tumor formation and development. LIM domains function as adaptors or scaffolds to support the assembly of multimeric protein complexes. They perform their functions through interactions with other protein partners. LIM domains are 50-60 amino acids in size and share two characteristic highly conserved zinc finger motifs. The two zinc fingers contain eight conserved residues, mostly cysteines and histidines, which coordinately bond to two zinc atoms. The consensus sequence of LIM domain has been defined as C-x(2)-C-x(16,23)-H-x(2)-[CH]-x(2)-C-x(2)-C-x(16,21)-C-x(2,3)-[CHD] (where X denotes any amino acid).

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*
gi 71985887   5 CARedCGKTVYPVEELKCLDKVWHKQCFKCTVCGMTLNMKNYKGYDKRPYCDPHY 59
Cdd:cd08368   1 CAG--CGKPIEGRELLRALGKKWHPECFKCAECGKPLGGDSFYEKDGKPYCEKCY 53

The second Lim domain of pollen specific protein SF3; The second Lim domain of pollen specific protein SF3: SF3 is a Lim protein that is found exclusively in mature plant pollen grains. It contains two LIM domains. The exact function of SF3 is unknown. It may be a transcription factor required for the expression of late pollen genes. It is possible that SF3 protein is involved in controlling pollen-specific processes such as male gamete maturation, pollen tube formation, or even fertilization. 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 71985887  10 CGKTVYPVEELKCLDKVWHKQCFKCTVCGMTLNMKNYKGYDKRPYCDPHY 59
Cdd:cd09441   4 CGKTVYPIEKVTVEGTSYHKSCFKCSHGGCTISPSNYAAHEGRLYCKHHH 53

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.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*.
gi 71985887 268 GFAVKAIYDYAAADKDEISFLEGDIIVNCEKIDDGWMTGTVQRTLQWGMLPANYVQ 323
Cdd:cd11917   4 GEPFQALYNYMPRNEDELELREGDVIDVMEKCDDGWFVGTSRRTKFFGTFPGNYVK 59

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

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....
gi 71985887 271 VKAIYDYAAADKDEISFLEGDIIVNCEKIDDGWMTGTVQRtlQWGMLPANYVQP 324
Cdd:cd11772   2 FRALYDYEAQHPDELSFEEGDLLYISDKSDPNWWKATCGG--KTGLIPSNYVEE 53

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.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|...
gi 71985887 271 VKAIYDYAAADKDEISFLEGDIIVNCEKIDDGWMTGTVQRTLqwGMLPANYVQ 323
Cdd:cd11826   2 VVALYDYTADKDDELSFQEGDIIYVTKKNDDGWYEGVLNGVT--GLFPGNYVE 52

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 71985887   5 CARedCGKTVYPVEELKCLDKVWHKQCFKCTVCGMTLNMKNYKGYDKRPYC 55
Cdd:cd09326   1 CPR--CGKSVYAAEEVIAAGKSWHKSCFTCAVCNKRLDSTTLAEHDGEIYC 49

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
                ....*....|....*....|....*....|....*....|....*....|....*....|.
gi 71985887 269 FAVKAIYDYAAADKDEISFLEGDIIV-----NCEKIDDGWMTGTVQRTLQWGMLPANYVQP 324
Cdd:cd11790   3 YKVRATHDYTAEDTDELTFEKGDVILvipfdDPEEQDEGWLMGVKESTGCRGVFPENFTER 63

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.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....
gi 71985887 270 AVKAIYDYAAADKDEISFLEGDIIVNCEKIDDGWMTGTVQRTLQwGMLPANYVQ 323
Cdd:cd11825   1 TVKALYDYRAQRPDELSFCKHAIITNVEKEDGGWWRGDYGGKKQ-KWFPANYVE 53

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
                ....*....|....*....|....*....|....*....|....*....|...
gi 71985887 271 VKAIYDYAAADKDEISFLEGDIIVNCEKIDDGWMTGTVQ-RTlqwGMLPANYV 322
Cdd:cd11873   2 VIVEFDYDAEEPDELTLKVGDIITNVKKMEEGWWEGTLNgKR---GMFPDNFV 51

Src homology 3 domain of Proline-Serine-Threonine Phosphatase-Interacting Protein 1; PSTPIP1, also called CD2 Binding Protein 1 (CD2BP1), is mainly expressed in hematopoietic cells. It is a binding partner of the cell surface receptor CD2 and PTP-PEST, a tyrosine phosphatase which functions in cell motility and Rac1 regulation. It also plays a role in the activation of the Wiskott-Aldrich syndrome protein (WASP), which couples actin rearrangement and T cell activation. Mutations in the gene encoding PSTPIP1 cause the autoinflammatory disorder known as PAPA (pyogenic sterile arthritis, pyoderma gangrenosum, and acne) syndrome. PSTPIP1 contains an N-terminal F-BAR domain, PEST motifs, 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 71985887 273 AIYDYAAADKDEISFLEGDIIVNCEKIDDGWMtgTVQRTLQWGMLPANYVQ 323
Cdd:cd11824   4 VLYDYTAQEDDELSISKGDVVAVIEKGEDGWW--TVERNGQKGLVPGTYLE 52

Src Homology 3 domain of GTPase Regulator Associated with Focal adhesion kinase and similar proteins; This subfamily is composed of Rho GTPase activating proteins (GAPs) with similarity to GRAF. Members contain an N-terminal BAR domain, followed by a Pleckstrin homology (PH) domain, a Rho GAP domain, and a C-terminal SH3 domain. Although vertebrates harbor four Rho GAPs in the GRAF subfamily including GRAF, GRAF2, GRAF3, and Oligophrenin-1 (OPHN1), only three are included in this model. OPHN1 contains the BAR, PH and GAP domains, but not the C-terminal SH3 domain. GRAF and GRAF2 show GAP activity towards RhoA and Cdc42. GRAF influences Rho-mediated cytoskeletal rearrangements and binds focal adhesion kinase. GRAF2 regulates caspase-activated p21-activated protein kinase-2. 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 71985887 271 VKAIYDYAAADKDEISFLEGDIIVNCEKID-DGWMTGTVQ-RTlqwGMLPANYVQP 324
Cdd:cd11882   2 ARALYACKAEDESELSFEPGQIITNVQPSDePGWLEGTLNgRT---GLIPENYVEF 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.

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gi 71985887 271 VKAIYDYAAADKDEISFLEGDIIVNCEKIDDGWMTGTVQRTLQWgmLPANYVQP 324
Cdd:cd11877   2 VRAKFNFEGTNEDELSFDKGDIITVTQVVEGGWWEGTLNGKTGW--FPSNYVKE 53

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 71985887 271 VKAIYDYAAADKDEISFLEGDIIVNCEKIDDGWMTGTVQ-RTlqwGMLPANYVQP 324
Cdd:cd11805   2 VQALYDFNPQEPGELEFRRGDIITVLDSSDPDWWKGELRgRV---GIFPANYVQP 53

Src Homology 3 domain of Ras GTPase-Activating Protein 1; RasGAP, also called Ras p21 protein activator, RASA1, or p120RasGAP, is part of the GAP1 family of GTPase-activating proteins. It is a 120kD cytosolic protein containing an SH3 domain flanked by two SH2 domains at the N-terminal end, a pleckstrin homology (PH) domain, a calcium dependent phospholipid binding domain (CaLB/C2), and a C-terminal catalytic GAP domain. It stimulates the GTPase activity of normal RAS p21. It acts as a positive effector of Ras in tumor cells. It also functions as a regulator downstream of tyrosine receptors such as those of PDGF, EGF, ephrin, and insulin, among others. The SH3 domain of RasGAP is unable to bind proline-rich sequences but have been shown to interact with protein partners such as the G3BP protein, Aurora kinases, and the Calpain small subunit 1. The RasGAP SH3 domain is necessary for the downstream signaling of Ras and it also influences Rho-mediated cytoskeletal reorganization. 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 71985887 271 VKAIYDY-AAADKDEISFLEGDIIVNCEKIDDGWMTGTVQRTLQWGMLPANYVQP 324
Cdd:cd11788   4 VRAILPYnKVPDTDELSFQKGDIFVVHNELEDGWLWVTSLRTGESGLVFRDLVEE 58

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 71985887 274 IYDYAAADKDEISFLEGDIIVNCEKIDDGWMTGTVQRTlQWGMLPANYVQ 323
Cdd:cd11962   5 LYDYEKDEDNEIELVEGEIVTNIEMVDEDWWMGTNSKG-ESGLFPSNYVE 53

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 71985887 273 AIYDYAAADKDEISFLEGDIIVNCEKI-----DDGWMTGTVQRTLqwGMLPANYVQP 324
Cdd:cd12058   4 ALYDYEASGEDELSLRRGDVVEVLSQDaavsgDDGWWAGKIRHRL--GIFPANYVTR 58

Fifth 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 71985887 272 KAIYDYAAADKDEISFLEGDIIVNCEKIDDGWMTGTVQRtlQWGMLPANY 321
Cdd:cd11818   3 RALYDFTGENEDELSFKAGDIITELESIDEEWMSGELRG--KSGIFPKNF 50

Src homology 3 domain of Endophilin-A; Endophilins play roles in synaptic vesicle formation, virus budding, mitochondrial morphology maintenance, receptor-mediated endocytosis inhibition, and endosomal sorting. They are classified into two types, A and B. Vertebrates contain three endophilin-A isoforms (A1, A2, and A3). Endophilin-A proteins are enriched in the brain and play multiple roles in receptor-mediated endocytosis. They tubulate membranes and regulate calcium influx into neurons to trigger the activation of the endocytic machinery. They are also involved in the sorting of plasma membrane proteins, actin filament assembly, and the uncoating of clathrin-coated vesicles for fusion with endosomes. Endophilins contain an N-terminal N-BAR domain (BAR domain with an additional N-terminal amphipathic helix), followed by a variable region containing proline clusters, 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 71985887 270 AVKAIYDYAAADKDEISFLEGDIIVNCEKIDDGWMTGTVQRtlQWGMLPANYVQ 323
Cdd:cd11803   2 CCRALYDFEPENEGELGFKEGDIITLTNQIDENWYEGMVNG--QSGFFPVNYVE 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.

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                ....*....|....*....|....*....|....*....|....*....|....*..
gi 71985887 268 GFAVKAIYDYAAADKDEISFLEGDIIVNCEKIDD-GWMTGtVQRTLQWGMLPANYVQ 323
Cdd:cd11999   1 GVRVRAVYDYTGQEPDELSFKAGEELLKVEDEDEqGWCKG-VTDGGAVGLYPANYVE 56

Src homology 3 domain of ArfGAP with SH3 domain, ankyrin repeat and PH domain containing proteins; ASAPs are Arf GTPase activating proteins (GAPs) and they function in regulating cell growth, migration, and invasion. They contain an N-terminal BAR domain, followed by a Pleckstrin homology (PH) domain, an Arf GAP domain, ankyrin (ANK) repeats, and a C-terminal SH3 domain. Vertebrates contain at least three members, ASAP1, ASAP2, and ASAP3, but some ASAP3 proteins do not seem to harbor a C-terminal SH3 domain. ASAP1 and ASAP2 show GTPase activating protein (GAP) activity towards Arf1 and Arf5. They do not show GAP activity towards Arf6, but are able to mediate Arf6 signaling by binding stably to GTP-Arf6. ASAP3 is an Arf6-specific GAP. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

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gi 71985887 271 VKAIYDYAAADKDEISFLEGDIIVNCEKIDDGWMTGTV----QRTlqwGMLPANY 321
Cdd:cd11821   2 VRALYDCQADNDDELTFSEGEIIVVTGEEDDEWWEGHIegdpSRR---GVFPVSF 53

Src homology 3 domain of Phospholipase C (PLC) gamma 2; PLCgamma2 is primarily expressed in haematopoietic cells, specifically in B cells. It is activated by tyrosine phosphorylation by B cell receptor (BCR) kinases and is recruited to the plasma membrane where its substrate is located. It is required in pre-BCR signaling and in the maturation of B cells. PLCs catalyze the hydrolysis of phosphatidylinositol (4,5)-bisphosphate [PtdIns(4,5)P2] to produce Ins(1,4,5)P3 and diacylglycerol (DAG). Ins(1,4,5)P3 initiates the calcium signaling cascade while DAG functions as an activator of PKC. 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. 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 71985887 270 AVKAIYDYAAADKDEISFLEGDIIVNCEKIDDGWMTGTVQRTLQWgMLPANYVQ 323
Cdd:cd11969   1 TVKALYDYRAKRSDELSFCKGALIHNVSKETGGWWKGDYGGKVQH-YFPSNYVE 53

The second LIM domain of Cysteine Rich Protein 3 (CRP3/MLP); The second 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. The second LIM domain of CRP3/MLP interacts with cytoskeletal protein beta-spectrin. CRP3/MLP also interacts with the basic helix-loop-helix myogenic transcription 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 71985887   5 CARedCGKTVYPVEELKCLDKVWHKQCFKCTVCGMTLNMKNYKGYDKRPYCDPHY 59
Cdd:cd09482   1 CPR--CGKSVYAAEKVMGGGKPWHKTCFRCAICGKSLESTTVTDKDGELYCKVCY 53

The first LIM domain of thymus LIM protein (TLP); The first LIM domain of thymus LIM protein (TLP): 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. 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 71985887   5 CARedCGKTVYPVEELKCLDKVWHKQCFKCTVCGMTLNMKNYKGYDKRPYCdpHYP 60
Cdd:cd09476   1 CPR--CDKTVYFAEKVSSLGKNWHRFCLKCERCSKILSPGGHAEHDGKPYC--HKP 52

Src Homology 3 domain of Insulin Receptor tyrosine kinase Substrate p53, Brain-specific Angiogenesis Inhibitor 1-Associated Protein 2 (BAIAP2)-Like proteins, and similar proteins; Proteins in this family include IRSp53, BAIAP2L1, BAIAP2L2, and similar proteins. They all contain an Inverse-Bin/Amphiphysin/Rvs (I-BAR) or IMD domain in addition to the SH3 domain. IRSp53, also known as BAIAP2, is a scaffolding protein that takes part in many signaling pathways including Cdc42-induced filopodia formation, Rac-mediated lamellipodia extension, and spine morphogenesis. IRSp53 exists as multiple splicing variants that differ mainly at the C-termini. BAIAP2L1, also called IRTKS (Insulin Receptor Tyrosine Kinase Substrate), serves as a substrate for the insulin receptor and binds the small GTPase Rac. It plays a role in regulating the actin cytoskeleton and colocalizes with F-actin, cortactin, VASP, and vinculin. IRSp53 and IRTKS also mediate the recruitment of effector proteins Tir and EspFu, which regulate host cell actin reorganization, to bacterial attachment sites. BAIAP2L2 co-localizes with clathrin plaques but its function has not been determined. The SH3 domains of IRSp53 and IRTKS have been shown to bind the proline-rich C-terminus of EspFu. 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 71985887 271 VKAIYDYAAADKDEISFLEGDII-VNCEKIDDGWMTGTVQRTLQWGMLPANYVQP 324
Cdd:cd11779   3 VKALYPHAAGGETQLSFEEGDVItLLGPEPRDGWHYGENERSGRRGWFPIAYTEP 57

a LIM domain subfamily on a group of proteins with unknown function; This model represents a LIM domain subfamily of Eplin-like family. This family shows highest homology to the LIM domains on Eplin and XIRP2 protein families. Epithelial Protein Lost in Neoplasm is a cytoskeleton-associated tumor suppressor whose expression inversely correlates with cell growth, motility, invasion and cancer mortality. Xirp2 is expressed in muscles and is an important effector of the Ang II signaling pathway in the heart. 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.

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gi 71985887  10 CGKTVYPVEELKCLDKVWHKQCFKCTVCGMTLNMKNYKGYDKRPYCDPHY 59
Cdd:cd09486   4 CQKTVYPMERLVADKLVFHNSCFCCKHCNAKLSLGSYAALHGEFYCKPHF 53

C-terminal Src homology 3 domain of GRB2-related adaptor protein 2; GRAP2 is also called GADS (GRB2-related adapter downstream of Shc), GrpL, GRB2L, Mona, or GRID (Grb2-related protein with insert domain). It is expressed specifically in the hematopoietic system. It 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. It also has roles in antigen-receptor and tyrosine kinase mediated signaling. GRAP2 is unique from other GRB2-like adaptor proteins in that it can be regulated by caspase cleavage. It contains an N-terminal SH3 domain, a central SH2 domain, and a C-terminal SH3 domain. The C-terminal SH3 domain of GRAP2 binds to different motifs found in substrate peptides including the typical PxxP motif in hematopoietic progenitor kinase 1 (HPK1), the RxxK motif in SLP-76 and HPK1, and the RxxxxK motif in phosphatase-like protein HD-PTP. 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 71985887 271 VKAIYDYAAADKDEISFLEGDIIVNCEKIDDGWMTGTVQRTLqwGMLPANYVQP 324
Cdd:cd11950   2 VRALYDFEALEDDELGFNSGDVIEVLDSSNPSWWKGRLHGKL--GLFPANYVAP 53

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.

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gi 71985887 271 VKAIYDYAAADKDEISFLEGDIIVNCEKIDDGWMTGTVQRTLQWGMLPANYVQ 323
Cdd:cd11793   2 VQCVHAYTAQQPDELTLEEGDVVNVLRKMPDGWYEGERLRDGERGWFPSSYTE 54

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 71985887 272 KAIYDYAAADKDEISFLEGD--IIVNCEKIDDGWMtgtVQR--TLQWGMLPANYVQP 324
Cdd:cd11775   4 KVLYDFDAQSDDELTVKEGDvvYILDDKKSKDWWM---VENvsTGKEGVVPASYIEI 57

The third LIM domain of actin binding LIM (abLIM) proteins; The third LIM domain of actin binding LIM (abLIM) proteins: Three homologous members of the abLIM protein family have been identified; abLIM-1, abLIM-2 and abLIM-3. The N-terminal of abLIM consists of four tandem repeats of LIM domains and the C-terminal of acting binding LIM protein is a villin headpiece domain, which has strong actin binding activity. The abLIM-1, which is expressed in retina, brain, and muscle tissue, has been indicated to function as a tumor suppressor. AbLIM-2 and -3, mainly expressed in muscle and neuronal tissue, bind to F-actin strongly. They may serve as a scaffold for signaling modules of the actin cytoskeleton and thereby modulate transcription. It has shown that LIM domains of abLIMs interact with STARS (striated muscle activator of Rho signaling), which directly binds actin and stimulates serum-response factor (SRF)-dependent transcription. All LIM domains are 50-60 amino acids in size and share two characteristic highly conserved 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 71985887  10 CGKTVYPVEELKCLDKVWHKQCFKCTVCGMTLNmKNYKGYDKRPYCDPHY 59
Cdd:cd09329   4 CGQEIKNGQALLALDKQWHVWCFKCKECGKVLT-GEYMGKDGKPYCERDY 52