Second Src homology 3 domain of Rab3-interacting molecules (RIMs) binding proteins; RIMs binding proteins (RBPs, RIM-BPs) associate with calcium channels present in photoreceptors, neurons, and hair cells; they interact simultaneously with specific calcium channel subunits, and active zone proteins, RIM1 and RIM2. RIMs are part of the matrix at the presynaptic active zone and are associated with synaptic vesicles through their interaction with the small GTPase Rab3. RIM-BPs play a role in regulating synaptic transmission by serving as adaptors and linking calcium channels with the synaptic vesicle release machinery. RIM-BPs contain three SH3 domains and two to three fibronectin III repeats. Invertebrates contain one, while vertebrates contain at least two RIM-BPs, RIM-BP1 and RIM-BP2. RIM-BP1 is also called peripheral-type benzodiazapine receptor associated protein 1 (PRAX-1). Mammals contain a third protein, RIM-BP3. RIM-BP1 and RIM-BP2 are predominantly expressed in the brain where they display overlapping but distinct expression patterns, while RIM-BP3 is almost exclusively expressed in the testis and is essential in spermiogenesis. The SH3 domains of RIM-BPs bind to the PxxP motifs of RIM1, RIM2, and L-type (alpha1D) and N-type (alpha1B) calcium channel subunits. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity. 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 1046851394 1183 VFVALFDYDPISMSPNPDAGEEELPFREGQILKVFGDKDADGFYRGESGGRTGYIPCNMVAE 1244
Cdd:cd12012      1 LFVALFDYDPLTMSPNPDAAEEELPFKEGQLIKVYGDKDADGFYLGEINGRRGLVPCNMVSE 62

First Src homology 3 domain of Rab3-interacting molecules (RIMs) binding proteins; RIMs binding proteins (RBPs, RIM-BPs) associate with calcium channels present in photoreceptors, neurons, and hair cells; they interact simultaneously with specific calcium channel subunits, and active zone proteins, RIM1 and RIM2. RIMs are part of the matrix at the presynaptic active zone and are associated with synaptic vesicles through their interaction with the small GTPase Rab3. RIM-BPs play a role in regulating synaptic transmission by serving as adaptors and linking calcium channels with the synaptic vesicle release machinery. RIM-BPs contain three SH3 domains and two to three fibronectin III repeats. Invertebrates contain one, while vertebrates contain at least two RIM-BPs, RIM-BP1 and RIM-BP2. RIM-BP1 is also called peripheral-type benzodiazapine receptor associated protein 1 (PRAX-1). Mammals contain a third protein, RIM-BP3. RIM-BP1 and RIM-BP2 are predominantly expressed in the brain where they display overlapping but distinct expression patterns, while RIM-BP3 is almost exclusively expressed in the testis and is essential in spermiogenesis. The SH3 domains of RIM-BPs bind to the PxxP motifs of RIM1, RIM2, and L-type (alpha1D) and N-type (alpha1B) calcium channel subunits. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity. 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 1046851394  217 VFLARYSYNPFE-GPNENPEAELPLTAGEYIYIYGNMDEDGFFEGELMDGRRGLVPSNFVER 277
Cdd:cd12014      1 VFVARYSYNPLRdSPNENPEAELPLNAGDYVYVYGDMDEDGFYEGELLDGRRGLVPSNFVER 62

Fibronectin type 3 domain; One of three types of internal repeats found in the plasma protein fibronectin. Its tenth fibronectin type III repeat contains an RGD cell recognition sequence in a flexible loop between 2 strands. Approximately 2% of all animal proteins contain the FN3 repeat; including extracellular and intracellular proteins, membrane spanning cytokine receptors, growth hormone receptors, tyrosine phosphatase receptors, and adhesion molecules. FN3-like domains are also found in bacterial glycosyl hydrolases.

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 1046851394  445 PSQLRIHRLTATSAEITWVPGNSNLAHAV-YL---------NGEECPPARPSTYWATFCNLRPGTLYQARVEA 507
Cdd:cd00063      4 PTNLRVTDVTSTSVTLSWTPPEDDGGPITgYVveyrekgsgDWKEVEVTPGSETSYTLTGLKPGTEYEFRVRA 76

Second Src homology 3 domain of Rab3-interacting molecules (RIMs) binding proteins; RIMs binding proteins (RBPs, RIM-BPs) associate with calcium channels present in photoreceptors, neurons, and hair cells; they interact simultaneously with specific calcium channel subunits, and active zone proteins, RIM1 and RIM2. RIMs are part of the matrix at the presynaptic active zone and are associated with synaptic vesicles through their interaction with the small GTPase Rab3. RIM-BPs play a role in regulating synaptic transmission by serving as adaptors and linking calcium channels with the synaptic vesicle release machinery. RIM-BPs contain three SH3 domains and two to three fibronectin III repeats. Invertebrates contain one, while vertebrates contain at least two RIM-BPs, RIM-BP1 and RIM-BP2. RIM-BP1 is also called peripheral-type benzodiazapine receptor associated protein 1 (PRAX-1). Mammals contain a third protein, RIM-BP3. RIM-BP1 and RIM-BP2 are predominantly expressed in the brain where they display overlapping but distinct expression patterns, while RIM-BP3 is almost exclusively expressed in the testis and is essential in spermiogenesis. The SH3 domains of RIM-BPs bind to the PxxP motifs of RIM1, RIM2, and L-type (alpha1D) and N-type (alpha1B) calcium channel subunits. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity. 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 1046851394 1183 VFVALFDYDPISMSPNPDAGEEELPFREGQILKVFGDKDADGFYRGESGGRTGYIPCNMVAE 1244
Cdd:cd12012      1 LFVALFDYDPLTMSPNPDAAEEELPFKEGQLIKVYGDKDADGFYLGEINGRRGLVPCNMVSE 62

First Src homology 3 domain of Rab3-interacting molecules (RIMs) binding proteins; RIMs binding proteins (RBPs, RIM-BPs) associate with calcium channels present in photoreceptors, neurons, and hair cells; they interact simultaneously with specific calcium channel subunits, and active zone proteins, RIM1 and RIM2. RIMs are part of the matrix at the presynaptic active zone and are associated with synaptic vesicles through their interaction with the small GTPase Rab3. RIM-BPs play a role in regulating synaptic transmission by serving as adaptors and linking calcium channels with the synaptic vesicle release machinery. RIM-BPs contain three SH3 domains and two to three fibronectin III repeats. Invertebrates contain one, while vertebrates contain at least two RIM-BPs, RIM-BP1 and RIM-BP2. RIM-BP1 is also called peripheral-type benzodiazapine receptor associated protein 1 (PRAX-1). Mammals contain a third protein, RIM-BP3. RIM-BP1 and RIM-BP2 are predominantly expressed in the brain where they display overlapping but distinct expression patterns, while RIM-BP3 is almost exclusively expressed in the testis and is essential in spermiogenesis. The SH3 domains of RIM-BPs bind to the PxxP motifs of RIM1, RIM2, and L-type (alpha1D) and N-type (alpha1B) calcium channel subunits. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity. 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 1046851394  217 VFLARYSYNPFE-GPNENPEAELPLTAGEYIYIYGNMDEDGFFEGELMDGRRGLVPSNFVER 277
Cdd:cd12014      1 VFVARYSYNPLRdSPNENPEAELPLNAGDYVYVYGDMDEDGFYEGELLDGRRGLVPSNFVER 62

Variant 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.

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|
gi 1046851394 1340 PMVAAFDYNPRENSPnmdveaeLPFRAGDVITVFGnMDDDGFYYGELNGQRGLVPSNFLE 1399
Cdd:pfam07653    1 YGRVIFDYVGTDKNG-------LTLKKGDVVKVLG-KDNDGWWEGETGGRVGLVPSTAVE 52

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 1046851394   226 PFEGPNENpeaELPLTAGEYIYIYgNMDEDGFFEGELMDGRRGLVPSNFVE 276
Cdd:smart00326   10 DYTAQDPD---ELSFKKGDIITVL-EKSDDGWWKGRLGRGKEGLFPSNYVE 56

Variant SH3 domain;

                           10        20        30        40        50
                   ....*....|....*....|....*....|....*....|....*....|....*..
gi 1046851394  220 ARYSYNPFEgpnenpEAELPLTAGEYIYIyGNMDEDGFFEGELmDGRRGLVPSNFVE 276
Cdd:pfam14604    1 ALYPYEPKD------DDELSLQRGDVITV-IEESEDGWWEGIN-TGRTGLVPANYVE 49

Ezrin/radixin/moesin, alpha-helical domain; The ERM family consists of three closely-related proteins, ezrin, radixin and moesin. Ezrin was first identified as a constituent of microvilli, radixin as a barbed, end-capping actin-modulating protein from isolated junctional fractions, and moesin as a heparin binding protein. A tumour suppressor molecule responsible for neurofibromatosis type 2 (NF2) is highly similar to ERM proteins and has been designated merlin (moesin-ezrin-radixin-like protein). ERM molecules contain 3 domains, an N-terminal globular domain, an extended alpha-helical domain and a charged C-terminal domain (pfam00769). Ezrin, radixin and merlin also contain a polyproline linker region between the helical and C-terminal domains. The N-terminal domain is highly conserved and is also found in merlin, band 4.1 proteins and members of the band 4.1 superfamily, designated the FERM domain. ERM proteins crosslink actin filaments with plasma membranes. They co-localize with CD44 at actin filament plasma membrane interaction sites, associating with CD44 via their N-terminal domains and with actin filaments via their C-terminal domains. This is the alpha-helical domain, which is involved in intramolecular masking of protein-protein interaction sites, regulating the activity of this proteins.

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1046851394    2 REVAQRRQQLEEEHEQARLSLQEK--------------QEEVRRLQQAQAEAKREHEgavQLLESTldSMQARVRE-LEG 66
Cdd:pfam20492    9 QELEERLKQYEEETKKAQEELEESeetaeeleeerrqaEEEAERLEQKRQEAEEEKE---RLEESA--EMEAEEKEqLEA 83

                           90
                   ....*....|....*...
gi 1046851394   67 QCRSQTERFSLLAQELQA 84
Cdd:pfam20492   84 ELAEAQEEIARLEEEVER 101

Fibronectin type 3 domain; One of three types of internal repeat within the plasma protein, fibronectin. The tenth fibronectin type III repeat contains a RGD cell recognition sequence in a flexible loop between 2 strands. Type III modules are present in both extracellular and intracellular proteins.

                            10        20        30        40        50        60        70
                    ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 1046851394   445 PSQLRIHRLTATSAEITWVPGNSNLAHAVYLN----------GEECPPARPSTYWATFCNLRPGTLYQARVEA 507
Cdd:smart00060    4 PSNLRVTDVTSTSVTLSWEPPPDDGITGYIVGyrveyreegsEWKEVNVTPSSTSYTLTGLKPGTEYEFRVRA 76

chromosome segregation protein SMC, primarily archaeal type; SMC (structural maintenance of chromosomes) proteins bind DNA and act in organizing and segregating chromosomes for partition. SMC proteins are found in bacteria, archaea, and eukaryotes. It is found in a single copy and is homodimeric in prokaryotes, but six paralogs (excluded from this family) are found in eukarotes, where SMC proteins are heterodimeric. This family represents the SMC protein of archaea and a few bacteria (Aquifex, Synechocystis, etc); the SMC of other bacteria is described by TIGR02168. The N- and C-terminal domains of this protein are well conserved, but the central hinge region is skewed in composition and highly divergent. [Cellular processes, Cell division, DNA metabolism, Chromosome-associated proteins]

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1046851394    2 REVAQRRQQLE---EEHEQARLSLQEKQEEVRRLQQAQAEAKREHEGAVQ---LLESTLDSMQARVRELEGQCRSQTERF 75
Cdd:TIGR02169  385 DELKDYREKLEklkREINELKRELDRLQEELQRLSEELADLNAAIAGIEAkinELEEEKEDKALEIKKQEWKLEQLAADL 464

                           90
                   ....*....|.
gi 1046851394   76 SLLAQELQAFR 86
Cdd:TIGR02169  465 SKYEQELYDLK 475

The Extended FES-CIP4 Homology (FCH) or F-BAR (FCH and Bin/Amphiphysin/Rvs) domain, a dimerization module that binds and bends membranes; F-BAR domains are dimerization modules that bind and bend membranes and are found in proteins involved in membrane dynamics and actin reorganization. F-BAR domain containing proteins, also known as Pombe Cdc15 homology (PCH) family proteins, include Fes and Fer tyrosine kinases, PACSINs/Syndapins, FCHO, PSTPIP, CIP4-like proteins and srGAPs. Many members also contain an SH3 domain and play roles in endocytosis. F-BAR domains form banana-shaped dimers with a positively-charged concave surface that binds to negatively-charged lipid membranes. They can induce membrane deformation in the form of long tubules. These tubules have diameters larger than those observed with N-BARs. The F-BAR domains of some members such as NOSTRIN and Rgd1 are important for the subcellular localization of the protein.

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1046851394    1 MREVAQRRQQLEEEHEQ-----ARLSLQEKQEEVRRLQQAQAEAKREHEGAVQLLESTLDSMQARVRELEGQCRSQTE-- 73
Cdd:cd07610     19 LREFLKKRAAIEEEYAKnlqklAKKFSKKPESGKTSLGTSWNSLREETESAATVHEELSEKLSQLIREPLEKVKEDKEqa 98

                           90
                   ....*....|....*
gi 1046851394   74 RFSLLAQELQAFRLH 88
Cdd:cd07610     99 RKKELAEGEKLKKKL 113

Second Src homology 3 domain of Rab3-interacting molecules (RIMs) binding proteins; RIMs binding proteins (RBPs, RIM-BPs) associate with calcium channels present in photoreceptors, neurons, and hair cells; they interact simultaneously with specific calcium channel subunits, and active zone proteins, RIM1 and RIM2. RIMs are part of the matrix at the presynaptic active zone and are associated with synaptic vesicles through their interaction with the small GTPase Rab3. RIM-BPs play a role in regulating synaptic transmission by serving as adaptors and linking calcium channels with the synaptic vesicle release machinery. RIM-BPs contain three SH3 domains and two to three fibronectin III repeats. Invertebrates contain one, while vertebrates contain at least two RIM-BPs, RIM-BP1 and RIM-BP2. RIM-BP1 is also called peripheral-type benzodiazapine receptor associated protein 1 (PRAX-1). Mammals contain a third protein, RIM-BP3. RIM-BP1 and RIM-BP2 are predominantly expressed in the brain where they display overlapping but distinct expression patterns, while RIM-BP3 is almost exclusively expressed in the testis and is essential in spermiogenesis. The SH3 domains of RIM-BPs bind to the PxxP motifs of RIM1, RIM2, and L-type (alpha1D) and N-type (alpha1B) calcium channel subunits. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity. 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 1046851394 1183 VFVALFDYDPISMSPNPDAGEEELPFREGQILKVFGDKDADGFYRGESGGRTGYIPCNMVAE 1244
Cdd:cd12012      1 LFVALFDYDPLTMSPNPDAAEEELPFKEGQLIKVYGDKDADGFYLGEINGRRGLVPCNMVSE 62

First Src homology 3 domain of Rab3-interacting molecules (RIMs) binding proteins; RIMs binding proteins (RBPs, RIM-BPs) associate with calcium channels present in photoreceptors, neurons, and hair cells; they interact simultaneously with specific calcium channel subunits, and active zone proteins, RIM1 and RIM2. RIMs are part of the matrix at the presynaptic active zone and are associated with synaptic vesicles through their interaction with the small GTPase Rab3. RIM-BPs play a role in regulating synaptic transmission by serving as adaptors and linking calcium channels with the synaptic vesicle release machinery. RIM-BPs contain three SH3 domains and two to three fibronectin III repeats. Invertebrates contain one, while vertebrates contain at least two RIM-BPs, RIM-BP1 and RIM-BP2. RIM-BP1 is also called peripheral-type benzodiazapine receptor associated protein 1 (PRAX-1). Mammals contain a third protein, RIM-BP3. RIM-BP1 and RIM-BP2 are predominantly expressed in the brain where they display overlapping but distinct expression patterns, while RIM-BP3 is almost exclusively expressed in the testis and is essential in spermiogenesis. The SH3 domains of RIM-BPs bind to the PxxP motifs of RIM1, RIM2, and L-type (alpha1D) and N-type (alpha1B) calcium channel subunits. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity. 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 1046851394  217 VFLARYSYNPFE-GPNENPEAELPLTAGEYIYIYGNMDEDGFFEGELMDGRRGLVPSNFVER 277
Cdd:cd12014      1 VFVARYSYNPLRdSPNENPEAELPLNAGDYVYVYGDMDEDGFYEGELLDGRRGLVPSNFVER 62

Src homology 3 domains of Rab3-interacting molecules (RIMs) binding proteins; RIMs binding proteins (RBPs, RIM-BPs) associate with calcium channels present in photoreceptors, neurons, and hair cells; they interact simultaneously with specific calcium channel subunits, and active zone proteins, RIM1 and RIM2. RIMs are part of the matrix at the presynaptic active zone and are associated with synaptic vesicles through their interaction with the small GTPase Rab3. RIM-BPs play a role in regulating synaptic transmission by serving as adaptors and linking calcium channels with the synaptic vesicle release machinery. RIM-BPs contain three SH3 domains and two to three fibronectin III repeats. Invertebrates contain one, while vertebrates contain at least two RIM-BPs, RIM-BP1 and RIM-BP2. RIM-BP1 is also called peripheral-type benzodiazapine receptor associated protein 1 (PRAX-1). Mammals contain a third protein, RIM-BP3. RIM-BP1 and RIM-BP2 are predominantly expressed in the brain where they display overlapping but distinct expression patterns, while RIM-BP3 is almost exclusively expressed in the testis and is essential in spermiogenesis. The SH3 domains of RIM-BPs bind to the PxxP motifs of RIM1, RIM2, and L-type (alpha1D) and N-type (alpha1B) calcium channel subunits. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity. 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 1046851394  217 VFLARYSYNPFEG-PNENPEAELPLTAGEYIYIYGNMDEDGFFEGELMDGRRGLVPSNFVE 276
Cdd:cd11851      1 LMVALYDYNPETMsPNDDPEEELSFHAGDVVRVYGPMDEDGFYYGELEGGRKGLVPSNFVQ 61

Src homology 3 domains of Rab3-interacting molecules (RIMs) binding proteins; RIMs binding proteins (RBPs, RIM-BPs) associate with calcium channels present in photoreceptors, neurons, and hair cells; they interact simultaneously with specific calcium channel subunits, and active zone proteins, RIM1 and RIM2. RIMs are part of the matrix at the presynaptic active zone and are associated with synaptic vesicles through their interaction with the small GTPase Rab3. RIM-BPs play a role in regulating synaptic transmission by serving as adaptors and linking calcium channels with the synaptic vesicle release machinery. RIM-BPs contain three SH3 domains and two to three fibronectin III repeats. Invertebrates contain one, while vertebrates contain at least two RIM-BPs, RIM-BP1 and RIM-BP2. RIM-BP1 is also called peripheral-type benzodiazapine receptor associated protein 1 (PRAX-1). Mammals contain a third protein, RIM-BP3. RIM-BP1 and RIM-BP2 are predominantly expressed in the brain where they display overlapping but distinct expression patterns, while RIM-BP3 is almost exclusively expressed in the testis and is essential in spermiogenesis. The SH3 domains of RIM-BPs bind to the PxxP motifs of RIM1, RIM2, and L-type (alpha1D) and N-type (alpha1B) calcium channel subunits. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity. 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 1046851394 1183 VFVALFDYDPISMSPNPDaGEEELPFREGQILKVFGDKDADGFYRGE-SGGRTGYIPCNMVAE 1244
Cdd:cd11851      1 LMVALYDYNPETMSPNDD-PEEELSFHAGDVVRVYGPMDEDGFYYGElEGGRKGLVPSNFVQE 62

Third Src homology 3 domain of Rab3-interacting molecules (RIMs) binding proteins; RIMs binding proteins (RBPs, RIM-BPs) associate with calcium channels present in photoreceptors, neurons, and hair cells; they interact simultaneously with specific calcium channel subunits, and active zone proteins, RIM1 and RIM2. RIMs are part of the matrix at the presynaptic active zone and are associated with synaptic vesicles through their interaction with the small GTPase Rab3. RIM-BPs play a role in regulating synaptic transmission by serving as adaptors and linking calcium channels with the synaptic vesicle release machinery. RIM-BPs contain three SH3 domains and two to three fibronectin III repeats. Invertebrates contain one, while vertebrates contain at least two RIM-BPs, RIM-BP1 and RIM-BP2. RIM-BP1 is also called peripheral-type benzodiazapine receptor associated protein 1 (PRAX-1). Mammals contain a third protein, RIM-BP3. RIM-BP1 and RIM-BP2 are predominantly expressed in the brain where they display overlapping but distinct expression patterns, while RIM-BP3 is almost exclusively expressed in the testis and is essential in spermiogenesis. The SH3 domains of RIM-BPs bind to the PxxP motifs of RIM1, RIM2, and L-type (alpha1D) and N-type (alpha1B) calcium channel subunits. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity. 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 1046851394  220 ARYSYNPFE-GPNENPEAELPLTAGEYIYIYGNMDEDGFFEGELmDGRRGLVPSNFVE 276
Cdd:cd12013      4 ALFDYDPREsSPNVDAEVELSFRAGDIITVFGEMDEDGFYYGEL-NGQRGLVPSNFLE 60

Second Src homology 3 domain of Rab3-interacting molecules (RIMs) binding proteins; RIMs binding proteins (RBPs, RIM-BPs) associate with calcium channels present in photoreceptors, neurons, and hair cells; they interact simultaneously with specific calcium channel subunits, and active zone proteins, RIM1 and RIM2. RIMs are part of the matrix at the presynaptic active zone and are associated with synaptic vesicles through their interaction with the small GTPase Rab3. RIM-BPs play a role in regulating synaptic transmission by serving as adaptors and linking calcium channels with the synaptic vesicle release machinery. RIM-BPs contain three SH3 domains and two to three fibronectin III repeats. Invertebrates contain one, while vertebrates contain at least two RIM-BPs, RIM-BP1 and RIM-BP2. RIM-BP1 is also called peripheral-type benzodiazapine receptor associated protein 1 (PRAX-1). Mammals contain a third protein, RIM-BP3. RIM-BP1 and RIM-BP2 are predominantly expressed in the brain where they display overlapping but distinct expression patterns, while RIM-BP3 is almost exclusively expressed in the testis and is essential in spermiogenesis. The SH3 domains of RIM-BPs bind to the PxxP motifs of RIM1, RIM2, and L-type (alpha1D) and N-type (alpha1B) calcium channel subunits. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity. 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 1046851394  217 VFLARYSYNPFE-GPNENP-EAELPLTAGEYIYIYGNMDEDGFFEGElMDGRRGLVPSNFVE 276
Cdd:cd12012      1 LFVALFDYDPLTmSPNPDAaEEELPFKEGQLIKVYGDKDADGFYLGE-INGRRGLVPCNMVS 61

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

                            10        20        30        40        50        60
                    ....*....|....*....|....*....|....*....|....*....|....*....|
gi 1046851394  1341 MVAAFDYNPREnspnmdvEAELPFRAGDVITVFgNMDDDGFYYGELN-GQRGLVPSNFLE 1399
Cdd:smart00326    5 VRALYDYTAQD-------PDELSFKKGDIITVL-EKSDDGWWKGRLGrGKEGLFPSNYVE 56

Variant 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.

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|...
gi 1046851394 1183 VFVALFDYDPismspnpdAGEEELPFREGQILKVFgDKDADGFYRGESGGRTGYIPCNMVAEV 1245
Cdd:pfam07653    1 YGRVIFDYVG--------TDKNGLTLKKGDVVKVL-GKDNDGWWEGETGGRVGLVPSTAVEEI 54

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 1046851394 1341 MVAAFDYNPREnspnmdvEAELPFRAGDVITVFgNMDDDGFYYGELN-GQRGLVPSNF 1397
Cdd:cd00174      2 ARALYDYEAQD-------DDELSFKKGDIITVL-EKDDDGWWEGELNgGREGLFPANY 51

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

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gi 1046851394 1183 VFVALFDYDPismsPNPDageeELPFREGQILKVFgDKDADGFYRGESGGRTGYIPCNMVAE 1244
Cdd:cd11772      1 VFRALYDYEA----QHPD----ELSFEEGDLLYIS-DKSDPNWWKATCGGKTGLIPSNYVEE 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.

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gi 1046851394 1183 VFVALFDYDPismspnpdAGEEELPFREGQILKVFgDKDADGFYRGES-GGRTGYIPCN 1240
Cdd:cd00174      1 YARALYDYEA--------QDDDELSFKKGDIITVL-EKDDDGWWEGELnGGREGLFPAN 50

Variant SH3 domain;

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gi 1046851394  220 ARYSYNPFEgpnenpEAELPLTAGEYIYIyGNMDEDGFFEGELmDGRRGLVPSNFVE 276
Cdd:pfam14604    1 ALYPYEPKD------DDELSLQRGDVITV-IEESEDGWWEGIN-TGRTGLVPANYVE 49

N-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 N-terminal SH3 domain of GRB2 binds to Sos and Sos-derived proline-rich peptides. 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 1046851394 1185 VALFDYDPismspnpdAGEEELPFREGQILKVFGDKDADGFYRGESGGRTGYIPCNMV 1242
Cdd:cd11804      3 VAKHDFKA--------TAEDELSFKKGSILKVLNMEDDPNWYKAELDGKEGLIPKNYI 52

Second Src Homology 3 domain of Bzz1 and similar domains; Bzz1 (or Bzz1p) is a WASP/Las17-interacting protein involved in endocytosis and trafficking to the vacuole. It physically interacts with type I myosins and functions in the early steps of endocytosis. Together with other proteins, it induces membrane scission in yeast. Bzz1 contains an N-terminal F-BAR (FES-CIP4 Homology and Bin/Amphiphysin/Rvs), a central coiled-coil, and two C-terminal SH3 domains. This model represents the second C-terminal SH3 domain. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

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gi 1046851394 1341 MVAAFDYNPRENSpnmdveaELPFRAGDVITVFGNMDDDGFYYGELNGQRGLVPSNF 1397
Cdd:cd11778      2 VEALYDYEAQGDD-------EISIRVGDRIAVIRGDDGSGWTYGEINGVKGLFPTSY 51

Src homology 3 domain of Nitric Oxide Synthase TRaffic INducer; Nostrin is expressed in endothelial and epithelial cells and is involved in the regulation, trafficking and targeting of endothelial NOS (eNOS). It facilitates the endocytosis of eNOS by coordinating the functions of dynamin and the Wiskott-Aldrich syndrome protein (WASP). Increased expression of Nostrin may be correlated to preeclampsia. Nostrin contains an N-terminal F-BAR domain and a C-terminal SH3 domain. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

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gi 1046851394 1342 VAAFDYNPRENSpnmdveaELPFRAGDVITVFgNMDDDGFYYGELNGQRGLVPSNFLE 1399
Cdd:cd11823      3 KALYSYTANRED-------ELSLQPGDIIEVH-EKQDDGWWLGELNGKKGIFPATYVE 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 1046851394 1343 AAFDYNPRENSpnmdveaELPFRAGDVITVFGNMDDDgFYYGELNGQRGLVPSNFLE 1399
Cdd:cd11805      4 ALYDFNPQEPG-------ELEFRRGDIITVLDSSDPD-WWKGELRGRVGIFPANYVQ 52

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

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gi 1046851394 1183 VFVALFDYDPIsmspnpdaGEEELPFREGQILKVFGDKDADGFY-RGESGGRTGYIPCN 1240
Cdd:cd11845      1 IYVALYDYEAR--------TDDDLSFKKGDRLQILDDSDGDWWLaRHLSTGKEGYIPSN 51

Fifth Src homology 3 domain (or SH3E) of Intersectin; Intersectins (ITSNs) are adaptor proteins that function in exo- and endocytosis, actin cytoskeletal reorganization, and signal transduction. They are essential for initiating clathrin-coated pit formation. They bind to many proteins through their multidomain structure and facilitate the assembly of multimeric complexes. Vertebrates contain two ITSN proteins, ITSN1 and ITSN2, which exist in alternatively spliced short and long isoforms. The short isoforms contain two Eps15 homology domains (EH1 and EH2), a coiled-coil region and five SH3 domains (SH3A-E), while the long isoforms, in addition, contain RhoGEF (also called Dbl-homologous or DH), Pleckstrin homology (PH) and C2 domains. ITSN1 and ITSN2 are both widely expressed, with variations depending on tissue type and stage of development. The fifth SH3 domain (or SH3E) of ITSN1 has been shown to bind many protein partners including SGIP1, Sos1, dynamin1/2, CIN85, c-Cbl, SHIP2, N-WASP, and synaptojanin-1, among others. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

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gi 1046851394 1342 VAAFDYNPREnspnmdvEAELPFRAGDVITVFgNMDDDGFYYGELNGQRGLVPSNFLE 1399
Cdd:cd11840      3 IALFPYTAQN-------EDELSFQKGDIINVL-SKDDPDWWRGELNGQTGLFPSNYVE 52

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 1046851394 1357 DVEAELPFRAGDVITVFGNMDDDGFYyGELNGQRGLVPSNF 1397
Cdd:cd11818     11 ENEDELSFKAGDIITELESIDEEWMS-GELRGKSGIFPKNF 50

Second 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. 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 1046851394 1186 ALFDYDPISmspnpdagEEELPFREGQILKVFGDKDADGFYRGESGGRTGYIPCNMV 1242
Cdd:cd11774      4 ALYDYDKQT--------EEELSFNEGDTLDVYDDSDSDWILVGFNGTQFGFVPANYI 52

N-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 have 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 N-terminal SH3 domain of the related protein GRB2 binds to Sos and Sos-derived proline-rich peptides. 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 1046851394 1359 EAELPFRAGDVITVFGNmdDDGFYYGELNGQRGLVPSNFLE 1399
Cdd:cd11947     13 EDELSFKKGDVLKILSS--DDIWFKAELNGEEGYVPKNFVD 51

Chromosome segregation ATPase Smc [Cell cycle control, cell division, chromosome partitioning];

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gi 1046851394    2 REVAQRRQQLEEEHEQARLSLQEKQEEVRRLQQAQAEAKRE---HEGAVQLLESTLDSMQARVRELEGQCRSQTERFSLL 78
Cdd:COG1196    256 EELEAELAELEAELEELRLELEELELELEEAQAEEYELLAElarLEQDIARLEERRRELEERLEELEEELAELEEELEEL 335

                   ....*.
gi 1046851394   79 AQELQA 84
Cdd:COG1196    336 EEELEE 341

N-terminal Src homology 3 domain of GRB2-related adaptor protein; GRAP is a GRB-2 like adaptor protein that is highly expressed in lymphoid tissues. It acts as a negative regulator of T cell receptor (TCR)-induced lymphocyte proliferation by downregulating the signaling to the Ras/ERK pathway. It has been identified as a regulator of TGFbeta signaling in diabetic kidney tubules and may have a role in the pathogenesis of the disease. GRAP contains an N-terminal SH3 domain, a central SH2 domain, and a C-terminal SH3 domain. The N-terminal SH3 domain of the related protein GRB2 binds to Sos and Sos-derived proline-rich peptides. 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 1046851394 1185 VALFDYdpismspnPDAGEEELPFREGQILKVFGDKDADGFYRGESGGRTGYIPCNMV 1242
Cdd:cd11948      3 VALYSF--------QATESDELPFQKGDILKILNMEDDQNWYKAELQGREGYIPKNYI 52

Src Homology 3 domain of Membrane Protein, Palmitoylated (or MAGUK p55 subfamily member) proteins; The MPP/p55 subfamily of MAGUK (membrane-associated guanylate kinase) proteins includes at least eight vertebrate members (MPP1-7 and CASK), four Drosophila proteins (Stardust, Varicose, CASK and Skiff), and other similar proteins; they all contain one each of the core of three domains characteristic of MAGUK proteins: PDZ, SH3, and guanylate kinase (GuK). In addition, most members except for MPP1 contain N-terminal L27 domains and some also contain a Hook (Protein 4.1 Binding) motif in between the SH3 and GuK domains. CASK has an additional calmodulin-dependent kinase (CaMK)-like domain at the N-terminus. Members of this subfamily are scaffolding proteins that play important roles in regulating and establishing cell polarity, cell adhesion, and synaptic targeting and transmission, among others. The GuK domain in MAGUK proteins is enzymatically inactive; instead, the domain mediates protein-protein interactions and associates intramolecularly with the SH3 domain. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

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gi 1046851394 1186 ALFDYDPI--SMSPNPDAGeeeLPFREGQILKVFGDKDAD---GFYRGESGGRTGYIPCNM 1241
Cdd:cd11862      4 ALFDYDPEedPLIPCKEAG---LSFKKGDILQIVNQDDPNwwqARKVGDPNGRAGLIPSQD 61

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 1046851394 1342 VAAFDYNPREnspnmdvEAELPFRAGDVITVFgNMDDDGFYYGELNGQRGLVPSNFLE 1399
Cdd:cd11824      3 SVLYDYTAQE-------DDELSISKGDVVAVI-EKGEDGWWTVERNGQKGLVPGTYLE 52

N-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 N-terminal SH3 domain of GRB2 binds to Sos and Sos-derived proline-rich peptides. 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 1046851394 1342 VAAFDYNPREnspnmdvEAELPFRAGDVITVFGNMDDDGFYYGELNGQRGLVPSNFL 1398
Cdd:cd11804      3 VAKHDFKATA-------EDELSFKKGSILKVLNMEDDPNWYKAELDGKEGLIPKNYI 52

C-terminal (or second) Src homology 3 domain of VAV proteins; VAV proteins function both as cytoplasmic guanine nucleotide exchange factors (GEFs) for Rho GTPases and scaffold proteins and they play important roles in cell signaling by coupling cell surface receptors to various effector functions. They play key roles in processes that require cytoskeletal reorganization including immune synapse formation, phagocytosis, cell spreading, and platelet aggregation, among others. Vertebrates have three VAV proteins (VAV1, VAV2, and VAV3). VAV proteins contain several domains that enable their function: N-terminal calponin homology (CH), acidic, RhoGEF (also called Dbl-homologous or DH), Pleckstrin Homology (PH), C1 (zinc finger), SH2, and two SH3 domains. The SH3 domain of VAV is involved in the localization of proteins to specific sites within the cell, by interacting with proline-rich sequences within target proteins. 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 1046851394 1342 VAAFDYNPRENSpnmdveaELPFRAGDVITVFGNMDDDGFYYGELNGQRGLVPSNFLE 1399
Cdd:cd11830      3 KARYDFCARDMR-------ELSLKEGDVVKIYNKKGQQGWWRGEINGRIGWFPSTYVE 53

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 1046851394 1186 ALFDYDPismspnpdAGEEELPFREGQILKVFGDKDaDGFYRGESGGRTGYIPCNMV 1242
Cdd:cd11803      5 ALYDFEP--------ENEGELGFKEGDIITLTNQID-ENWYEGMVNGQSGFFPVNYV 52

First Src Homology 3 domain (SH3A) of CD2-associated protein; CD2AP, also called CMS (Cas ligand with Multiple SH3 domains) or METS1 (Mesenchyme-to-Epithelium Transition protein with SH3 domains), is a cytosolic adaptor protein that plays a role in regulating the cytoskeleton. It is critical in cell-to-cell union necessary for kidney function. It also stabilizes the contact between a T cell and antigen-presenting cells. It is primarily expressed in podocytes at the cytoplasmic face of the slit diaphragm and serves as a linker anchoring podocin and nephrin to the actin cytoskeleton. CD2AP contains three SH3 domains, a proline-rich region, and a C-terminal coiled-coil domain. All of these domains enable CD2AP to bind various protein partners and assemble complexes that have been implicated in many different functions. This alignment model represents the first SH3 domain (SH3A) of CD2AP. SH3A binds to the PXXXPR motif present in c-Cbl and the cytoplasmic domain of cell adhesion protein CD2. Its interaction with CD2 anchors CD2 at sites of cell contact. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

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gi 1046851394 1359 EAELPFRAGDVITVFGNMDDDGFYYGELNGQRGLVPSNFLE 1399
Cdd:cd12053     13 EDELTIRVGEIIRNVKKLEEEGWLEGELNGRRGMFPDNFVK 53