NCBI Conserved Domain Search

The phosphoinositide binding Phox Homology domain of Five SH protein; The PX domain is a phosphoinositide (PI) binding module present in many proteins with diverse functions such as cell signaling, vesicular trafficking, protein sorting, and lipid modification, among others. Five SH (FISH), also called Tks5, is a scaffolding protein and Src substrate that is localized in podosomes, which are electron-dense structures found in Src-transformed fibroblasts, osteoclasts, macrophages, and some invasive cancer cells. FISH contains an N-terminal PX domain and five Src homology 3 (SH3) domains. FISH binds and regulates some members of the ADAMs family of transmembrane metalloproteases, which function as sheddases and mediators of cell and matrix interactions. It is required for podosome formation, degradation of the extracellular matrix, and cancer cell invasion. This subfamily also includes proteins with a different number of SH3 domains than FISH, such as Tks4, which contains four SH3 domains instead of five. The Tks4 adaptor protein is required for the formation of functional podosomes. It has overlapping, but not identical, functions as FISH. The PX domain is involved in targeting of proteins to PI-enriched membranes, and may also be involved in protein-protein interaction.

Pssm-ID: 132798 Cd Length: 119 Bit Score: 247.34 E-value: 2.02e-77

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 63055065   7 IVEVKVLDVQKRRVPNKHYVYIIRVTWSSGATEAIYRRYSKFFDLQMQMLDKFPMEGGQKDPKQRIIPFLPGKILFRRSH 86
Cdd:cd06888   1 VKDVKVIDVEKRRAPSKHYVYIINVTWSDGSSNVIYRRYSKFFDLQMQLLDKFPIEGGQKDPSQRIIPFLPGKILFRRSH 80

                        90       100       110
                ....*....|....*....|....*....|....*....
gi 63055065  87 IRDVAVKRLIPIDEYCKALIQLPPYISQCDEVLQFFETR 125
Cdd:cd06888  81 IRDVAVKRLKPIDEYCKALVRLPPHISQCDEVLRFFEAK 119

Second Src homology 3 domain of Tyrosine kinase substrate with four SH3 domains; Tks4, also called SH3 and PX domain-containing protein 2B (SH3PXD2B) or HOFI, is a Src substrate and scaffolding protein that plays an important role in the formation of podosomes and invadopodia, the dynamic actin-rich structures that are related to cell migration and cancer cell invasion. It is required in the formation of functional podosomes, EGF-induced membrane ruffling, and lamellipodia generation. It plays an important role in cellular attachment and cell spreading. Tks4 is essential for the localization of MT1-MMP (membrane-type 1 matrix metalloproteinase) to invadopodia. It contains an N-terminal Phox homology (PX) domain and four SH3 domains. This model characterizes the second SH3 domain of Tks4. 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.

Pssm-ID: 213009 [Multi-domain] Cd Length: 54 Bit Score: 129.77 E-value: 5.39e-36

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....
gi 63055065 224 EKYTVIYPYTARDQDEMNLERGAVVEVVQKNLEGWWKIRYQGKEGWAPASYLKK 277
Cdd:cd12076   1 EKYTVIYPYTARDQDEINLEKGAVVEVIQKNLEGWWKIRYQGKEGWAPASYLKK 54

First Src homology 3 domain of Tyrosine kinase substrate with four SH3 domains; Tks4, also called SH3 and PX domain-containing protein 2B (SH3PXD2B) or HOFI, is a Src substrate and scaffolding protein that plays an important role in the formation of podosomes and invadopodia, the dynamic actin-rich structures that are related to cell migration and cancer cell invasion. It is required in the formation of functional podosomes, EGF-induced membrane ruffling, and lamellipodia generation. It plays an important role in cellular attachment and cell spreading. Tks4 is essential for the localization of MT1-MMP (membrane-type 1 matrix metalloproteinase) to invadopodia. It contains an N-terminal Phox homology (PX) domain and four SH3 domains. This model characterizes the first SH3 domain of Tks4. 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.

Pssm-ID: 213008 Cd Length: 55 Bit Score: 129.42 E-value: 6.15e-36

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*
gi 63055065 155 EQYVVVADYQKQESSEISLSVGQVVDIIEKNESGWWFVSTAEEQGWVPATCLEGQ 209
Cdd:cd12075   1 DQYVVVANYQKQESSEISLYVGQVVDIIEKNESGWWFVSTADEQGWVPATCLEAQ 55

Fourth (C-terminal) Src homology 3 domain of Tyrosine kinase substrate with four SH3 domains; Tks4, also called SH3 and PX domain-containing protein 2B (SH3PXD2B) or HOFI, is a Src substrate and scaffolding protein that plays an important role in the formation of podosomes and invadopodia, the dynamic actin-rich structures that are related to cell migration and cancer cell invasion. It is required in the formation of functional podosomes, EGF-induced membrane ruffling, and lamellipodia generation. It plays an important role in cellular attachment and cell spreading. Tks4 is essential for the localization of MT1-MMP (membrane-type 1 matrix metalloproteinase) to invadopodia. It contains an N-terminal Phox homology (PX) domain and four SH3 domains. This model characterizes the fourth (C-terminal) SH3 domain of Tks4. 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.

Pssm-ID: 212951 Cd Length: 56 Bit Score: 125.39 E-value: 1.81e-34

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*.
gi 63055065 851 LYVAVANFEGDEDTSSFQEGTVFEVREKNSSGWWFCQVLSGAPSWEGWIPSNYLRK 906
Cdd:cd12018   1 LYVAVADFEGDEDTSSFKEGTVFEVREKNSSGWWFCKVLSGGPVWEGWIPSNYLRK 56

Third Src homology 3 domain of Tyrosine kinase substrate with four SH3 domains; Tks4, also called SH3 and PX domain-containing protein 2B (SH3PXD2B) or HOFI, is a Src substrate and scaffolding protein that plays an important role in the formation of podosomes and invadopodia, the dynamic actin-rich structures that are related to cell migration and cancer cell invasion. It is required in the formation of functional podosomes, EGF-induced membrane ruffling, and lamellipodia generation. It plays an important role in cellular attachment and cell spreading. Tks4 is essential for the localization of MT1-MMP (membrane-type 1 matrix metalloproteinase) to invadopodia. It contains an N-terminal Phox homology (PX) domain and four SH3 domains. This model characterizes the third SH3 domain of Tks4. 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.

Pssm-ID: 213011 Cd Length: 53 Bit Score: 118.64 E-value: 3.70e-32

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|...
gi 63055065 372 EYYTIAEFQTTIPDGISFQAGLKVEVIEKSLSGWWYIQMEDKEGWAPATFIDK 424
Cdd:cd12078   1 EYYTIADFQTTIPDGISFQAGLKVEVIEKNLSGWWYIQIEDKEGWAPATFIDK 53

First Src homology 3 domain of Tyrosine kinase substrate (Tks) proteins; Tks proteins are Src substrates and scaffolding proteins that play important roles in the formation of podosomes and invadopodia, the dynamic actin-rich structures that are related to cell migration and cancer cell invasion. Vertebrates contain two Tks proteins, Tks4 (Tyr kinase substrate with four SH3 domains) and Tks5 (Tyr kinase substrate with five SH3 domains), which display partially overlapping but non-redundant functions. Both associate with the ADAMs family of transmembrane metalloproteases, which function as sheddases and mediators of cell and matrix interactions. Tks5 interacts with N-WASP and Nck, while Tks4 is essential for the localization of MT1-MMP (membrane-type 1 matrix metalloproteinase) to invadopodia. Tks proteins contain an N-terminal Phox homology (PX) domain and four or five SH3 domains. This model characterizes the first SH3 domain of Tks 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.

Pssm-ID: 212948 Cd Length: 53 Bit Score: 114.82 E-value: 8.55e-31

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|...
gi 63055065 156 QYVVVADYQKQESSEISLSVGQVVDIIEKNESGWWFVSTAEEQGWVPATCLEG 208
Cdd:cd12015   1 QYVVVADYKKQQPNEISLRAGDVVDVIEKNENGWWFVSLEDEQGWVPATYLEP 53

First Src homology 3 domain of Tyrosine kinase substrate with five SH3 domains; Tks5, also called SH3 and PX domain-containing protein 2A (SH3PXD2A) or Five SH (FISH), is a scaffolding protein and Src substrate that is localized in podosomes, which are electron-dense structures found in Src-transformed fibroblasts, osteoclasts, macrophages, and some invasive cancer cells. It binds and regulates some members of the ADAMs family of transmembrane metalloproteases, which function as sheddases and mediators of cell and matrix interactions. It is required for podosome formation, degradation of the extracellular matrix, and cancer cell invasion. Tks5 contains an N-terminal Phox homology (PX) domain and five SH3 domains. This model characterizes the first SH3 domain of Tks5. 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.

Pssm-ID: 213007 [Multi-domain] Cd Length: 53 Bit Score: 111.34 E-value: 1.30e-29

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|..
gi 63055065 156 QYVVVADYQKQESSEISLSVGQVVDIIEKNESGWWFVSTAEEQGWVPATCLE 207
Cdd:cd12074   1 QYVVVSNYEKQENSEISLQAGEVVDVIEKNESGWWFVSTAEEQGWVPATYLE 52

Second Src homology 3 domain of Tyrosine kinase substrate (Tks) proteins; Tks proteins are Src substrates and scaffolding proteins that play important roles in the formation of podosomes and invadopodia, the dynamic actin-rich structures that are related to cell migration and cancer cell invasion. Vertebrates contain two Tks proteins, Tks4 (Tyr kinase substrate with four SH3 domains) and Tks5 (Tyr kinase substrate with five SH3 domains), which display partially overlapping but non-redundant functions. Both associate with the ADAMs family of transmembrane metalloproteases, which function as sheddases and mediators of cell and matrix interactions. Tks5 interacts with N-WASP and Nck, while Tks4 is essential for the localization of MT1-MMP (membrane-type 1 matrix metalloproteinase) to invadopodia. Tks proteins contain an N-terminal Phox homology (PX) domain and four or five SH3 domains. This model characterizes the second SH3 domain of Tks 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.

Pssm-ID: 212949 Cd Length: 54 Bit Score: 111.01 E-value: 1.95e-29

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....
gi 63055065 224 EKYTVIYPYTARDQDEMNLERGAVVEVVQKNLEGWWKIRYQGKEGWAPASYLKK 277
Cdd:cd12016   1 EKYITTQAYKAENEDEIGFETGVVVEVIQKNLDGWWKIRYQGKEGWAPATYLKK 54

The phosphoinositide binding Phox Homology domain of the p47phox subunit of NADPH oxidase; The PX domain is a phosphoinositide (PI) binding module present in many proteins with diverse functions such as cell signaling, vesicular trafficking, protein sorting, and lipid modification, among others. p47phox is a cytosolic subunit of the phagocytic NADPH oxidase complex (also called Nox2 or gp91phox), which plays a key role in the ability of phagocytes to defend against bacterial infections. NADPH oxidase catalyzes the transfer of electrons from NADPH to oxygen during phagocytosis forming superoxide and reactive oxygen species. p47phox is required for activation of NADH oxidase and plays a role in translocation. It contains an N-terminal PX domain, two Src Homology 3 (SH3) domains, and a C-terminal domain that contains PxxP motifs for binding SH3 domains. The PX domain of p47phox is unique in that it contains two distinct basic pockets on the membrane-binding surface: one preferentially binds phosphatidylinositol-3,4-bisphosphate [PI(3,4)P2] and is analogous to the PI3P-binding pocket of p40phox, while the other binds anionic phospholipids such as phosphatidic acid or phosphatidylserine. Simultaneous binding in the two pockets results in increased membrane affinity. The PX domain of p47phox is also involved in protein-protein interaction.

Pssm-ID: 132797 Cd Length: 118 Bit Score: 112.62 E-value: 3.38e-29

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 63055065   7 IVEVKVLDVQKRRVPNKHYVYIIRVTWSSGATEAIYRRYSKFFDLQMQMLDKFPMEGGQKDPKQRIIPFLPGKILFRRsh 86
Cdd:cd06887   1 IRHIALLGFEKRFVPSQHYVYMFLVKWQDLSEKLVYRRFTEIYEFHKTLKEMFPIEAGDINKENRIIPHLPAPKWFDG-- 78

                        90       100       110       120
                ....*....|....*....|....*....|....*....|.
gi 63055065  87 iRDVAVKRLIPIDEYCKALIQLPPYISQCDEVLQFFETRPE 127
Cdd:cd06887  79 -QRAAENRQGTLTEYCSTLLSLPPKISRCPHVLDFFKVRPD 118

Third Src homology 3 domain of Tyrosine kinase substrate (Tks) proteins; Tks proteins are Src substrates and scaffolding proteins that play important roles in the formation of podosomes and invadopodia, the dynamic actin-rich structures that are related to cell migration and cancer cell invasion. Vertebrates contain two Tks proteins, Tks4 (Tyr kinase substrate with four SH3 domains) and Tks5 (Tyr kinase substrate with five SH3 domains), which display partially overlapping but non-redundant functions. Both associate with the ADAMs family of transmembrane metalloproteases, which function as sheddases and mediators of cell and matrix interactions. Tks5 interacts with N-WASP and Nck, while Tks4 is essential for the localization of MT1-MMP (membrane-type 1 matrix metalloproteinase) to invadopodia. Tks proteins contain an N-terminal Phox homology (PX) domain and four or five SH3 domains. This model characterizes the third SH3 domain of Tks 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.

Pssm-ID: 212950 Cd Length: 53 Bit Score: 107.15 E-value: 3.64e-28

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|...
gi 63055065 372 EYYTIAEFQTTIPDGISFQAGLKVEVIEKSLSGWWYIQMEDKEGWAPATFIDK 424
Cdd:cd12017   1 EYFTIGEFQATIQDGISFQKGQKVEVIDKNPSGWWYVKIDGKEGWAPSSYIEK 53

The phosphoinositide binding Phox Homology domain of the p40phox subunit of NADPH oxidase; The PX domain is a phosphoinositide binding module present in many proteins with diverse functions such as cell signaling, vesicular trafficking, protein sorting, and lipid modification, among others. p40phox contains an N-terminal PX domain, a central SH3 domain that binds p47phox, and a C-terminal PB1 domain that interacts with p67phox. It is a cytosolic subunit of the phagocytic NADPH oxidase complex (also called Nox2 or gp91phox) which plays a crucial role in the cellular response to bacterial infection. NADPH oxidase catalyzes the transfer of electrons from NADPH to oxygen during phagocytosis forming superoxide and reactive oxygen species. p40phox positively regulates NADPH oxidase in both phosphatidylinositol-3-phosphate (PI3P)-dependent and PI3P-independent manner. The PX domain is a phospholipid-binding module involved in the membrane targeting of proteins. The p40phox PX domain binds to PI3P, an abundant lipid in phagosomal membranes, playing an important role in the localization of NADPH oxidase. The PX domain of p40phox is also involved in protein-protein interaction.

Pssm-ID: 132792 Cd Length: 123 Bit Score: 108.68 E-value: 9.05e-28

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 63055065   8 VEVKVLDVQKRRVPNKHYVYIIRVTWSSGATEAIYRRYSKFFDLQMQMLDKFPMEGGqKDPKQRIIPFLPGKILFRRShi 87
Cdd:cd06882   4 VSATIADIEEKRGFTNYYVFVIEVKTKGGSKYLIYRRYRQFFALQSKLEERFGPEAG-SSAYDCTLPTLPGKIYVGRK-- 80

                        90       100       110       120
                ....*....|....*....|....*....|....*....|.
gi 63055065  88 RDVAVKRLIPIDEYCKALIQLPPYISQCDEVLQFFETRPED 128
Cdd:cd06882  81 AEIAERRIPLLNRYMKELLSLPVWVLMDEDVRLFFYQTESD 121

Second Src homology 3 domain of Tyrosine kinase substrate with five SH3 domains; Tks5, also called SH3 and PX domain-containing protein 2A (SH3PXD2A) or Five SH (FISH), is a scaffolding protein and Src substrate that is localized in podosomes, which are electron-dense structures found in Src-transformed fibroblasts, osteoclasts, macrophages, and some invasive cancer cells. It binds and regulates some members of the ADAMs family of transmembrane metalloproteases, which function as sheddases and mediators of cell and matrix interactions. It is required for podosome formation, degradation of the extracellular matrix, and cancer cell invasion. Tks5 contains an N-terminal Phox homology (PX) domain and five SH3 domains. This model characterizes the second SH3 domain of Tks5. 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.

Pssm-ID: 213010 Cd Length: 54 Bit Score: 97.80 E-value: 9.17e-25

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....
gi 63055065 224 EKYTVIYPYTARDQDEMNLERGAVVEVVQKNLEGWWKIRYQGKEGWAPASYLKK 277
Cdd:cd12077   1 EKYVTVQPYTSQGKDEIGFEKGVTVEVIQKNLEGWWYIRYLGKEGWAPASYLKK 54

Fifth (C-terminal) Src homology 3 domain of Tyrosine kinase substrate with five SH3 domains; Tks5, also called SH3 and PX domain-containing protein 2A (SH3PXD2A) or Five SH (FISH), is a scaffolding protein and Src substrate that is localized in podosomes, which are electron-dense structures found in Src-transformed fibroblasts, osteoclasts, macrophages, and some invasive cancer cells. It binds and regulates some members of the ADAMs family of transmembrane metalloproteases, which function as sheddases and mediators of cell and matrix interactions. It is required for podosome formation, degradation of the extracellular matrix, and cancer cell invasion. Tks5 contains an N-terminal Phox homology (PX) domain and five SH3 domains. This model characterizes the fifth (C-terminal) SH3 domain of Tks5. 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.

Pssm-ID: 212953 Cd Length: 57 Bit Score: 93.49 E-value: 2.85e-23

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*..
gi 63055065 851 LYVAVANFEGDEDTSSFQEGTVFEVREKNSSGWWFCQVLSGAPSWEGWIPSNYLRKK 907
Cdd:cd12020   1 VYVSIADYEGDEETAGFQEGVSMEVLEKNPNGWWYCQILDGVKPFKGWVPSNYLEKK 57

Third Src homology 3 domain of Tyrosine kinase substrate with five SH3 domains; Tks5, also called SH3 and PX domain-containing protein 2A (SH3PXD2A) or Five SH (FISH), is a scaffolding protein and Src substrate that is localized in podosomes, which are electron-dense structures found in Src-transformed fibroblasts, osteoclasts, macrophages, and some invasive cancer cells. It binds and regulates some members of the ADAMs family of transmembrane metalloproteases, which function as sheddases and mediators of cell and matrix interactions. It is required for podosome formation, degradation of the extracellular matrix, and cancer cell invasion. Tks5 contains an N-terminal Phox homology (PX) domain and five SH3 domains. This model characterizes the third SH3 domain of Tks5. 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.

Pssm-ID: 213012 Cd Length: 54 Bit Score: 92.80 E-value: 5.51e-23

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|...
gi 63055065 372 EYYTIAEFQTTIPDGISFQAGLKVEVIEKSLSGWWYIQMEDKEGWAPATFIDK 424
Cdd:cd12079   2 EYYTIAEFQSCISDGISFRGGQKAEVIEKNSGGWWYVQIGEKEGWAPSSYIDK 54

PhoX homologous domain, present in p47phox and p40phox; Eukaryotic domain of unknown function present in phox proteins, PLD isoforms, a PI3K isoform.

Pssm-ID: 214610 Cd Length: 105 Bit Score: 93.56 E-value: 1.01e-22

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 63055065     12 VLDVQKRRvPNKHYVYIIRVTWSSGATEA-IYRRYSKFFDLQMQMLDKFPMeggqkdpkqRIIPFLPGKILFRR--SHIR 88
Cdd:smart00312   1 VVEPEKIG-DGKHYYYVIEIETKTGLEEWtVSRRYSDFLELHSKLKKHFPR---------SILPPLPGKKLFGRlnNFSE 70

                           90       100       110
                   ....*....|....*....|....*....|....*
gi 63055065     89 DVAVKRLIPIDEYCKALIQLPPYISQCDEVLQFFE 123
Cdd:smart00312  71 EFIEKRRRGLEKYLQSLLNHPELINHSEVVLEFLE 105

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

Pssm-ID: 212790 [Multi-domain] Cd Length: 53 Bit Score: 88.46 E-value: 1.47e-21

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|...
gi 63055065 372 EYYTIAEFQTTIPDGISFQAGLKVEVIEKSLSGWWYIQMEDKEGWAPATFIDK 424
Cdd:cd11856   1 SYVAIADYEAQGDDEISLQEGEVVEVLEKNDSGWWYVRKGDKEGWVPASYLEP 53

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

Pssm-ID: 212790 [Multi-domain] Cd Length: 53 Bit Score: 87.31 E-value: 3.60e-21

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|..
gi 63055065 156 QYVVVADYQKQESSEISLSVGQVVDIIEKNESGWWFVSTAEEQGWVPATCLE 207
Cdd:cd11856   1 SYVAIADYEAQGDDEISLQEGEVVEVLEKNDSGWWYVRKGDKEGWVPASYLE 52

The phosphoinositide binding Phox Homology Domain of Class II Phosphoinositide 3-Kinases; The PX domain is a phosphoinositide (PI) binding module present in many proteins with diverse functions. The Phosphoinositide 3-Kinase (PI3K) family of enzymes catalyzes the phosphorylation of the 3-hydroxyl group of the inositol ring of phosphatidylinositol. PI3Ks play an important role in a variety of fundamental cellular processes, including cell motility, the Ras pathway, vesicle trafficking and secretion, immune cell activation and apoptosis. They are also involved in the regulation of clathrin-mediated membrane trafficking as well as ATP-dependent priming of neurosecretory granule exocytosis. PI3Ks are divided into three main classes (I, II, and III) based on their substrate specificity, regulation, and domain structure. Class II PI3Ks preferentially use PI as a substrate to produce PI3P, but can also phosphorylate PI4P to produce PI(3,4)P2. They function as monomers and do not associate with any regulatory subunits. Class II enzymes contain an N-terminal Ras binding domain, a lipid binding C2 domain, a PI3K homology domain of unknown function, an ATP-binding cataytic domain, a PX domain, and a second C2 domain at the C-terminus. Class II PI3Ks include three vertebrate isoforms (alpha, beta, and gamma), the Drosophila PI3K_68D, and similar proteins.

Pssm-ID: 132793 Cd Length: 109 Bit Score: 88.95 E-value: 5.06e-21

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 63055065   9 EVKVLDVQKRRVPNKHYVYIIRVTwSSGATEA--IYRRYSKFFDLQMQMLDKFPMEGgqkdpkqriIPFLPGKILFRRSH 86
Cdd:cd06883   1 EVSVFGFQKRYSPEKYYIYVVKVT-RENQTEPsfVFRTFEEFQELHNKLSLLFPSLK---------LPSFPARVVLGRSH 70

                        90       100       110
                ....*....|....*....|....*....|....*.
gi 63055065  87 IRDVAVKRLIPIDEYCKALIQLPPYISQCDEVLQFF 122
Cdd:cd06883  71 IKQVAERRKIELNSYLKSLFNASPEVAESDLVYTFF 106

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

Pssm-ID: 212790 [Multi-domain] Cd Length: 53 Bit Score: 83.84 E-value: 6.37e-20

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|...
gi 63055065 225 KYTVIYPYTARDQDEMNLERGAVVEVVQKNLEGWWKIRYQGKEGWAPASYLKK 277
Cdd:cd11856   1 SYVAIADYEAQGDDEISLQEGEVVEVLEKNDSGWWYVRKGDKEGWVPASYLEP 53

The Phox Homology domain, a phosphoinositide binding module; The PX domain is a phosphoinositide (PI) binding module involved in targeting proteins to membranes. Proteins containing PX domains interact with PIs and have been implicated in highly diverse functions such as cell signaling, vesicular trafficking, protein sorting, lipid modification, cell polarity and division, activation of T and B cells, and cell survival. Many members of this superfamily bind phosphatidylinositol-3-phosphate (PI3P) but in some cases, other PIs such as PI4P or PI(3,4)P2, among others, are the preferred substrates. In addition to protein-lipid interaction, the PX domain may also be involved in protein-protein interaction, as in the cases of p40phox, p47phox, and some sorting nexins (SNXs). The PX domain is conserved from yeast to humans and is found in more than 100 proteins. The majority of PX domain-containing proteins are SNXs, which play important roles in endosomal sorting.

Pssm-ID: 132768 [Multi-domain] Cd Length: 106 Bit Score: 82.41 E-value: 8.01e-19

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 63055065   9 EVKVLDVQKRR-VPNKHYVYIIRVTWSSGATEAIYRRYSKFFDLQMQMLDKFPmeggqkdpkQRIIPFLPGKILFRRsHI 87
Cdd:cd06093   1 SVSIPDYEKVKdGGKKYVVYIIEVTTQGGEEWTVYRRYSDFEELHEKLKKKFP---------GVILPPLPPKKLFGN-LD 70

                        90       100       110
                ....*....|....*....|....*....|....*.
gi 63055065  88 RDVAVKRLIPIDEYCKALIQLPPyISQCDEVLQFFE 123
Cdd:cd06093  71 PEFIEERRKQLEQYLQSLLNHPE-LRNSEELKEFLE 105

The phosphoinositide binding Phox Homology Domain of Class II Phosphoinositide 3-Kinases similar to the Drosophila PI3K_68D protein; The PX domain is a phosphoinositide (PI) binding module present in many proteins with diverse functions. The Phosphoinositide 3-Kinase (PI3K) family of enzymes catalyzes the phosphorylation of the 3-hydroxyl group of the inositol ring of phosphatidylinositol. PI3Ks play an important role in a variety of fundamental cellular processes, including cell motility, the Ras pathway, vesicle trafficking and secretion, immune cell activation and apoptosis. PI3Ks are divided into three main classes (I, II, and III) based on their substrate specificity, regulation, and domain structure. Class II PI3Ks preferentially use PI as a substrate to produce PI3P, but can also phosphorylate PI4P to produce PI(3,4)P2. They function as monomers and do not associate with any regulatory subunits. Class II enzymes contain an N-terminal Ras binding domain, a lipid binding C2 domain, a PI3K homology domain of unknown function, an ATP-binding cataytic domain, a PX domain, and a second C2 domain at the C-terminus. PI3K_68D is a novel PI3K which is widely expressed throughout the Drosophila life cycle. In vitro, it has been shown to phosphorylate PI and PI4P. It is involved in signaling pathways that affect pattern formation of Drosophila wings.

Pssm-ID: 132794 Cd Length: 111 Bit Score: 80.54 E-value: 4.62e-18

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 63055065   7 IVEVKVLDVQKRRVPNKHYVYIIRVTWSSGATEA-IYRRYSKFFDLQMQMLDKFPMEGgqkdpkqriIPFLPGKILFRRS 85
Cdd:cd06884   1 IVRVTVVGFQKRYDPEKYYVYVVEVTRENQASPQhVFRTYKEFLELYQKLCRKFPLAK---------LHPLSTGSHVGRS 71

                        90       100       110
                ....*....|....*....|....*....|....*..
gi 63055065  86 HIRDVAVKRLIPIDEYCKALIQLPPYISQCDEVLQFF 122
Cdd:cd06884  72 NIKSVAEKRKQDIQQFLNSLFKMAEEVSHSDLVYTFF 108

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

Pssm-ID: 212790 [Multi-domain] Cd Length: 53 Bit Score: 78.45 E-value: 5.58e-18

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*.
gi 63055065 852 YVAVANFEGDEDTS-SFQEGTVFEVREKNSSGWWFCQVLsgapSWEGWIPSNYLRK 906
Cdd:cd11856   2 YVAIADYEAQGDDEiSLQEGEVVEVLEKNDSGWWYVRKG----DKEGWVPASYLEP 53

The phosphoinositide binding Phox Homology domain of Bem1p; The PX domain is a phosphoinositide (PI) binding module present in many proteins with diverse functions such as cell signaling, vesicular trafficking, protein sorting, and lipid modification, among others. Members of this subfamily bear similarity to Saccharomyces cerevisiae Bem1p, containing two Src Homology 3 (SH3) domains at the N-terminus, a central PX domain, and a C-terminal PB1 domain. Bem1p is a scaffolding protein that is critical for proper Cdc42p activation during bud formation in yeast. During budding and mating, Bem1p migrates to the plasma membrane where it can serve as an adaptor for Cdc42p and some other proteins. Bem1p also functions as an effector of the G1 cyclin Cln3p and the cyclin-dependent kinase Cdc28p in promoting vacuolar fusion. The PX domain is involved in targeting of proteins to PI-enriched membranes, and may also be involved in protein-protein interaction. The PX domain of Bem1p specifically binds phosphatidylinositol-4-phosphate (PI4P).

Pssm-ID: 132800 Cd Length: 112 Bit Score: 78.48 E-value: 2.84e-17

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 63055065  22 NKHYVYIIRVTWSSGATEAIYRRYSKFFDLQMQMLDKFPMEGGQKDPKqRIIPFLPGkilfRRSHIRDVAV--KRLIPID 99
Cdd:cd06890  12 DNRYWYRVRATLSDGKTRYLCRYYQDFYKLHIALLDLFPAEAGRNSSK-RILPYLPG----PVTDVVNDSIslKRLNDLN 86

                        90       100
                ....*....|....*....|....*.
gi 63055065 100 EYCKALIQLPPYISQCDEVLQFFETR 125
Cdd:cd06890  87 EYLNELINLPAYIQTSEVVRDFFANR 112

The phosphoinositide binding Phox Homology domain of Nox Organizing protein 1; The PX domain is a phosphoinositide (PI) binding module present in many proteins with diverse functions such as cell signaling, vesicular trafficking, protein sorting, and lipid modification, among others. Nox Organizing protein 1 (NoxO1) is a critical regulator of enzyme kinetics of the nonphagocytic NADPH oxidase Nox1, which catalyzes the transfer of electrons from NADPH to molecular oxygen to form superoxide. Nox1 is expressed in colon, stomach, uterus, prostate, and vascular smooth muscle cells. NoxO1, a homolog of the p47phox subunit of phagocytic NADPH oxidase, is involved in targeting activator subunits (such as NoxA1) to Nox1. It is co-localized with Nox1 in the membranes of resting cells and directs the subcellular localization of Nox1. The PX domain is involved in targeting of proteins to PI-enriched membranes, and may also be involved in protein-protein interaction. The PX domain of NoxO1 preferentially binds phosphatidylinositol-3,5-bisphosphate [PI(3,5)P2], PI5P, and PI4P.

Pssm-ID: 132799 Cd Length: 121 Bit Score: 77.04 E-value: 8.81e-17

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 63055065   5 RSIVEVKVLDVQKRRvpnKHYVYIIRVTWSSGATEAIYRRYSKFFDLQMQMLDKFPMEGGQKDPKQRIIPFLPGKIL--- 81
Cdd:cd06889   3 RHPVDVQGVGVMQKR---RHKTYMFSVLWSDGSELFVYRSLEEFRKLHKQLKEKFPVEAGLLRSSDRVLPKFKDAPSlgs 79

                        90       100       110       120
                ....*....|....*....|....*....|....*....|.
gi 63055065  82 FRRSHIRDVAVKRLipIDEYCKALIQLPPYISQCDEVLQFF 122
Cdd:cd06889  80 LKGSTSRSLARLKL--LETYCQELLRLDEKVSRSPEVIQFF 118

The phosphoinositide binding Phox Homology Domain of the Alpha Isoform of Class II Phosphoinositide 3-Kinases; The PX domain is a phosphoinositide (PI) binding module present in many proteins with diverse functions. The Phosphoinositide 3-Kinase (PI3K) family of enzymes catalyzes the phosphorylation of the 3-hydroxyl group of the inositol ring of phosphatidylinositol. PI3Ks play an important role in a variety of fundamental cellular processes, including cell motility, the Ras pathway, vesicle trafficking and secretion, immune cell activation and apoptosis. PI3Ks are divided into three main classes (I, II, and III) based on their substrate specificity, regulation, and domain structure. Class II PI3Ks preferentially use PI as a substrate to produce PI3P, but can also phosphorylate PI4P to produce PI(3,4)P2. They function as monomers and do not associate with any regulatory subunits. Class II enzymes contain an N-terminal Ras binding domain, a lipid binding C2 domain, a PI3K homology domain of unknown function, an ATP-binding cataytic domain, a PX domain, and a second C2 domain at the C-terminus. The class II alpha isoform, PI3K-C2alpha, plays key roles in clathrin assembly and clathrin-mediated membrane trafficking, insulin signaling, vascular smooth muscle contraction, and the priming of neurosecretory granule exocytosis. The PX domain is involved in targeting of proteins to PI-enriched membranes, and may also be involved in protein-protein interaction.

Pssm-ID: 132822 Cd Length: 109 Bit Score: 75.35 E-value: 2.91e-16

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 63055065   9 EVKVLDVQKRRVPNKHYVYIIRVTwSSGATEA--IYRRYSKFFDLQMQMLDKFPMEGgqkdpkqriIPFLPGKILFRRSH 86
Cdd:cd07289   1 EVSVFTYHKRYNPDKHYIYVVRIL-REGQIEPsfVFRTFDEFQELHNKLSILFPLWK---------LPGFPNKMVLGRTH 70

                        90       100       110
                ....*....|....*....|....*....|....*.
gi 63055065  87 IRDVAVKRLIPIDEYCKALIQLPPYISQCDEVLQFF 122
Cdd:cd07289  71 IKDVAAKRKVELNSYIQSLMNSSTEVAECDLVYTFF 106

Second Src homology 3 domain of Tyrosine kinase substrate (Tks) proteins; Tks proteins are Src substrates and scaffolding proteins that play important roles in the formation of podosomes and invadopodia, the dynamic actin-rich structures that are related to cell migration and cancer cell invasion. Vertebrates contain two Tks proteins, Tks4 (Tyr kinase substrate with four SH3 domains) and Tks5 (Tyr kinase substrate with five SH3 domains), which display partially overlapping but non-redundant functions. Both associate with the ADAMs family of transmembrane metalloproteases, which function as sheddases and mediators of cell and matrix interactions. Tks5 interacts with N-WASP and Nck, while Tks4 is essential for the localization of MT1-MMP (membrane-type 1 matrix metalloproteinase) to invadopodia. Tks proteins contain an N-terminal Phox homology (PX) domain and four or five SH3 domains. This model characterizes the second SH3 domain of Tks 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.

Pssm-ID: 212949 Cd Length: 54 Bit Score: 71.72 E-value: 1.30e-15

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....
gi 63055065 371 EEYYTIAEFQTTIPDGISFQAGLKVEVIEKSLSGWWYIQMEDKEGWAPATFIDK 424
Cdd:cd12016   1 EKYITTQAYKAENEDEIGFETGVVVEVIQKNLDGWWKIRYQGKEGWAPATYLKK 54

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.

Pssm-ID: 214620 [Multi-domain] Cd Length: 56 Bit Score: 69.87 E-value: 5.49e-15

                           10        20        30        40        50
                   ....*....|....*....|....*....|....*....|....*....|....*.
gi 63055065    222 EEEKYTVIYPYTARDQDEMNLERGAVVEVVQKNLEGWWKIRYQ-GKEGWAPASYLK 276
Cdd:smart00326   1 EGPQVRALYDYTAQDPDELSFKKGDIITVLEKSDDGWWKGRLGrGKEGLFPSNYVE 56

Second Src homology 3 domain of Tyrosine kinase substrate with five SH3 domains; Tks5, also called SH3 and PX domain-containing protein 2A (SH3PXD2A) or Five SH (FISH), is a scaffolding protein and Src substrate that is localized in podosomes, which are electron-dense structures found in Src-transformed fibroblasts, osteoclasts, macrophages, and some invasive cancer cells. It binds and regulates some members of the ADAMs family of transmembrane metalloproteases, which function as sheddases and mediators of cell and matrix interactions. It is required for podosome formation, degradation of the extracellular matrix, and cancer cell invasion. Tks5 contains an N-terminal Phox homology (PX) domain and five SH3 domains. This model characterizes the second SH3 domain of Tks5. 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.

Pssm-ID: 213010 Cd Length: 54 Bit Score: 68.52 E-value: 1.43e-14

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....
gi 63055065 371 EEYYTIAEFQTTIPDGISFQAGLKVEVIEKSLSGWWYIQMEDKEGWAPATFIDK 424
Cdd:cd12077   1 EKYVTVQPYTSQGKDEIGFEKGVTVEVIQKNLEGWWYIRYLGKEGWAPASYLKK 54

First or N-terminal Src homology 3 domain of the p47phox subunit of NADPH oxidase, also called Neutrophil Cytosolic Factor 1; p47phox, or NCF1, is a cytosolic subunit of the phagocytic NADPH oxidase complex (also called Nox2 or gp91phox), which plays a key role in the ability of phagocytes to defend against bacterial infections. NADPH oxidase catalyzes the transfer of electrons from NADPH to oxygen during phagocytosis forming superoxide and reactive oxygen species. p47phox is required for activation of NADH oxidase and plays a role in translocation. It contains an N-terminal Phox homology (PX) domain, tandem SH3 domains (N-SH3 and C-SH3), a polybasic/autoinhibitory region, and a C-terminal proline-rich region (PRR). This model characterizes the first SH3 domain (or N-SH3) of p47phox. In its inactive state, the tandem SH3 domains interact intramolecularly with the autoinhibitory region; upon activation, the tandem SH3 domains are exposed through a conformational change, resulting in their binding to the PRR of p22phox and the activation of NADPH oxidase. 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.

Pssm-ID: 212954 [Multi-domain] Cd Length: 53 Bit Score: 68.44 E-value: 1.67e-14

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|.
gi 63055065 157 YVVVADYQKQESSEISLSVGQVVDIIEKNESGWWFVSTAEEQGWVPATCLE 207
Cdd:cd12021   2 YRAIADYEKSSKSEMALKTGDVVEVVEKSENGWWFCQLKAKRGWVPASYLE 52

PX domain; PX domains bind to phosphoinositides.

Pssm-ID: 459940 Cd Length: 84 Bit Score: 68.42 E-value: 3.53e-14

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 63055065    41 IYRRYSKFFDLQMQMLDKFPmeggqkdpkQRIIPFLPGKILFRRSHiRDVAVKRLIPIDEYCKALIQLPPyISQCDEVLQ 120
Cdd:pfam00787  11 VRRRYSDFVELHKKLLRKFP---------SVIIPPLPPKRWLGRYN-EEFIEKRRKGLEQYLQRLLQHPE-LRNSEVLLE 79


                  ....*
gi 63055065   121 FFETR 125
Cdd:pfam00787  80 FLESD 84

First Src homology 3 domain of Tyrosine kinase substrate (Tks) proteins; Tks proteins are Src substrates and scaffolding proteins that play important roles in the formation of podosomes and invadopodia, the dynamic actin-rich structures that are related to cell migration and cancer cell invasion. Vertebrates contain two Tks proteins, Tks4 (Tyr kinase substrate with four SH3 domains) and Tks5 (Tyr kinase substrate with five SH3 domains), which display partially overlapping but non-redundant functions. Both associate with the ADAMs family of transmembrane metalloproteases, which function as sheddases and mediators of cell and matrix interactions. Tks5 interacts with N-WASP and Nck, while Tks4 is essential for the localization of MT1-MMP (membrane-type 1 matrix metalloproteinase) to invadopodia. Tks proteins contain an N-terminal Phox homology (PX) domain and four or five SH3 domains. This model characterizes the first SH3 domain of Tks 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.

Pssm-ID: 212948 Cd Length: 53 Bit Score: 66.67 E-value: 6.44e-14

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|...
gi 63055065 372 EYYTIAEFQTTIPDGISFQAGLKVEVIEKSLSGWWYIQMEDKEGWAPATFIDK 424
Cdd:cd12015   1 QYVVVADYKKQQPNEISLRAGDVVDVIEKNENGWWFVSLEDEQGWVPATYLEP 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.

Pssm-ID: 212690 [Multi-domain] Cd Length: 51 Bit Score: 62.87 E-value: 1.43e-12

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|.
gi 63055065 225 KYTVIYPYTARDQDEMNLERGAVVEVVQKNLEGWWKIRYQ-GKEGWAPASY 274
Cdd:cd00174   1 YARALYDYEAQDDDELSFKKGDIITVLEKDDDGWWEGELNgGREGLFPANY 51

First Src homology 3 domain of Tyrosine kinase substrate (Tks) proteins; Tks proteins are Src substrates and scaffolding proteins that play important roles in the formation of podosomes and invadopodia, the dynamic actin-rich structures that are related to cell migration and cancer cell invasion. Vertebrates contain two Tks proteins, Tks4 (Tyr kinase substrate with four SH3 domains) and Tks5 (Tyr kinase substrate with five SH3 domains), which display partially overlapping but non-redundant functions. Both associate with the ADAMs family of transmembrane metalloproteases, which function as sheddases and mediators of cell and matrix interactions. Tks5 interacts with N-WASP and Nck, while Tks4 is essential for the localization of MT1-MMP (membrane-type 1 matrix metalloproteinase) to invadopodia. Tks proteins contain an N-terminal Phox homology (PX) domain and four or five SH3 domains. This model characterizes the first SH3 domain of Tks 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.

Pssm-ID: 212948 Cd Length: 53 Bit Score: 62.82 E-value: 1.54e-12

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|...
gi 63055065 225 KYTVIYPYTARDQDEMNLERGAVVEVVQKNLEGWWKIRYQGKEGWAPASYLKK 277
Cdd:cd12015   1 QYVVVADYKKQQPNEISLRAGDVVDVIEKNENGWWFVSLEDEQGWVPATYLEP 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.

Pssm-ID: 214620 [Multi-domain] Cd Length: 56 Bit Score: 62.94 E-value: 1.64e-12

                           10        20        30        40        50
                   ....*....|....*....|....*....|....*....|....*....|....
gi 63055065    155 EQYVVVADYQKQESSEISLSVGQVVDIIEKNESGWWFVST-AEEQGWVPATCLE 207
Cdd:smart00326   3 PQVRALYDYTAQDPDELSFKKGDIITVLEKSDDGWWKGRLgRGKEGLFPSNYVE 56

First Src homology 3 domain of Tyrosine kinase substrate with five SH3 domains; Tks5, also called SH3 and PX domain-containing protein 2A (SH3PXD2A) or Five SH (FISH), is a scaffolding protein and Src substrate that is localized in podosomes, which are electron-dense structures found in Src-transformed fibroblasts, osteoclasts, macrophages, and some invasive cancer cells. It binds and regulates some members of the ADAMs family of transmembrane metalloproteases, which function as sheddases and mediators of cell and matrix interactions. It is required for podosome formation, degradation of the extracellular matrix, and cancer cell invasion. Tks5 contains an N-terminal Phox homology (PX) domain and five SH3 domains. This model characterizes the first SH3 domain of Tks5. 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.

Pssm-ID: 213007 [Multi-domain] Cd Length: 53 Bit Score: 62.42 E-value: 2.14e-12

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|..
gi 63055065 372 EYYTIAEFQTTIPDGISFQAGLKVEVIEKSLSGWWYIQMEDKEGWAPATFID 423
Cdd:cd12074   1 QYVVVSNYEKQENSEISLQAGEVVDVIEKNESGWWFVSTAEEQGWVPATYLE 52

Second or C-terminal Src homology 3 domain of NADPH oxidase (Nox) Organizing protein 1; Nox Organizing protein 1 (NoxO1) is a critical regulator of enzyme kinetics of the nonphagocytic NADPH oxidase Nox1, which catalyzes the transfer of electrons from NADPH to molecular oxygen to form superoxide. Nox1 is expressed in colon, stomach, uterus, prostate, and vascular smooth muscle cells. NoxO1 is involved in targeting activator subunits (such as NoxA1) to Nox1. It is co-localized with Nox1 in the membranes of resting cells and directs the subcellular localization of Nox1. NoxO1 contains an N-terminal Phox homology (PX) domain, tandem SH3 domains (N-SH3 and C-SH3), and a C-terminal proline-rich region (PRR). This model characterizes the second SH3 domain (or C-SH3) of NoxO1. The tandem SH3 domains of NoxO1 interact with the PRR of p22phox, which also complexes with Nox1. 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.

Pssm-ID: 212957 Cd Length: 53 Bit Score: 62.35 E-value: 2.16e-12

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|.
gi 63055065 226 YTVIYPYTARDQDEMNLERGAVVEVVQKNLEGWWKIRYQGKEGWAPASYLK 276
Cdd:cd12024   2 YYATRAYEAQKEDELSVPAGVVVEVLQKSDNGWWLIRYNGRAGYVPSMYLQ 52

Second Src homology 3 domain of Tyrosine kinase substrate (Tks) proteins; Tks proteins are Src substrates and scaffolding proteins that play important roles in the formation of podosomes and invadopodia, the dynamic actin-rich structures that are related to cell migration and cancer cell invasion. Vertebrates contain two Tks proteins, Tks4 (Tyr kinase substrate with four SH3 domains) and Tks5 (Tyr kinase substrate with five SH3 domains), which display partially overlapping but non-redundant functions. Both associate with the ADAMs family of transmembrane metalloproteases, which function as sheddases and mediators of cell and matrix interactions. Tks5 interacts with N-WASP and Nck, while Tks4 is essential for the localization of MT1-MMP (membrane-type 1 matrix metalloproteinase) to invadopodia. Tks proteins contain an N-terminal Phox homology (PX) domain and four or five SH3 domains. This model characterizes the second SH3 domain of Tks 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.

Pssm-ID: 212949 Cd Length: 54 Bit Score: 61.32 E-value: 4.97e-12

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|...
gi 63055065 155 EQYVVVADYQKQESSEISLSVGQVVDIIEKNESGWWFVSTAEEQGWVPATCLE 207
Cdd:cd12016   1 EKYITTQAYKAENEDEIGFETGVVVEVIQKNLDGWWKIRYQGKEGWAPATYLK 53

Third Src homology 3 domain of Tyrosine kinase substrate (Tks) proteins; Tks proteins are Src substrates and scaffolding proteins that play important roles in the formation of podosomes and invadopodia, the dynamic actin-rich structures that are related to cell migration and cancer cell invasion. Vertebrates contain two Tks proteins, Tks4 (Tyr kinase substrate with four SH3 domains) and Tks5 (Tyr kinase substrate with five SH3 domains), which display partially overlapping but non-redundant functions. Both associate with the ADAMs family of transmembrane metalloproteases, which function as sheddases and mediators of cell and matrix interactions. Tks5 interacts with N-WASP and Nck, while Tks4 is essential for the localization of MT1-MMP (membrane-type 1 matrix metalloproteinase) to invadopodia. Tks proteins contain an N-terminal Phox homology (PX) domain and four or five SH3 domains. This model characterizes the third SH3 domain of Tks 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.

Pssm-ID: 212950 Cd Length: 53 Bit Score: 61.31 E-value: 5.74e-12

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|..
gi 63055065 156 QYVVVADYQKQESSEISLSVGQVVDIIEKNESGWWFVSTAEEQGWVPATCLE 207
Cdd:cd12017   1 EYFTIGEFQATIQDGISFQKGQKVEVIDKNPSGWWYVKIDGKEGWAPSSYIE 52

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.

Pssm-ID: 394975 [Multi-domain] Cd Length: 47 Bit Score: 60.68 E-value: 6.62e-12

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*..
gi 63055065   227 TVIYPYTARDQDEMNLERGAVVEVVQKNLEGWWKIRYQ-GKEGWAPA 272
Cdd:pfam00018   1 VALYDYTAQEPDELSFKKGDIIIVLEKSEDGWWKGRNKgGKEGLIPS 47

First Src homology 3 domain of Tyrosine kinase substrate with four SH3 domains; Tks4, also called SH3 and PX domain-containing protein 2B (SH3PXD2B) or HOFI, is a Src substrate and scaffolding protein that plays an important role in the formation of podosomes and invadopodia, the dynamic actin-rich structures that are related to cell migration and cancer cell invasion. It is required in the formation of functional podosomes, EGF-induced membrane ruffling, and lamellipodia generation. It plays an important role in cellular attachment and cell spreading. Tks4 is essential for the localization of MT1-MMP (membrane-type 1 matrix metalloproteinase) to invadopodia. It contains an N-terminal Phox homology (PX) domain and four SH3 domains. This model characterizes the first SH3 domain of Tks4. 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.

Pssm-ID: 213008 Cd Length: 55 Bit Score: 60.09 E-value: 1.65e-11

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|...
gi 63055065 371 EEYYTIAEFQTTIPDGISFQAGLKVEVIEKSLSGWWYIQMEDKEGWAPATFID 423
Cdd:cd12075   1 DQYVVVANYQKQESSEISLYVGQVVDIIEKNESGWWFVSTADEQGWVPATCLE 53

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.

Pssm-ID: 212758 [Multi-domain] Cd Length: 53 Bit Score: 59.31 E-value: 2.36e-11

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|...
gi 63055065 225 KYTVIYPYTARDQDEMNLERGAVVEVVQKNLEGWWKIRYQGKEGWAPASYLKK 277
Cdd:cd11824   1 KYSVLYDYTAQEDDELSISKGDVVAVIEKGEDGWWTVERNGQKGLVPGTYLEK 53

Third Src homology 3 domain of Tyrosine kinase substrate (Tks) proteins; Tks proteins are Src substrates and scaffolding proteins that play important roles in the formation of podosomes and invadopodia, the dynamic actin-rich structures that are related to cell migration and cancer cell invasion. Vertebrates contain two Tks proteins, Tks4 (Tyr kinase substrate with four SH3 domains) and Tks5 (Tyr kinase substrate with five SH3 domains), which display partially overlapping but non-redundant functions. Both associate with the ADAMs family of transmembrane metalloproteases, which function as sheddases and mediators of cell and matrix interactions. Tks5 interacts with N-WASP and Nck, while Tks4 is essential for the localization of MT1-MMP (membrane-type 1 matrix metalloproteinase) to invadopodia. Tks proteins contain an N-terminal Phox homology (PX) domain and four or five SH3 domains. This model characterizes the third SH3 domain of Tks 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.

Pssm-ID: 212950 Cd Length: 53 Bit Score: 59.39 E-value: 2.56e-11

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|..
gi 63055065 226 YTVIYPYTARDQDEMNLERGAVVEVVQKNLEGWWKIRYQGKEGWAPASYLKK 277
Cdd:cd12017   2 YFTIGEFQATIQDGISFQKGQKVEVIDKNPSGWWYVKIDGKEGWAPSSYIEK 53

Second Src homology 3 domain of Tyrosine kinase substrate with four SH3 domains; Tks4, also called SH3 and PX domain-containing protein 2B (SH3PXD2B) or HOFI, is a Src substrate and scaffolding protein that plays an important role in the formation of podosomes and invadopodia, the dynamic actin-rich structures that are related to cell migration and cancer cell invasion. It is required in the formation of functional podosomes, EGF-induced membrane ruffling, and lamellipodia generation. It plays an important role in cellular attachment and cell spreading. Tks4 is essential for the localization of MT1-MMP (membrane-type 1 matrix metalloproteinase) to invadopodia. It contains an N-terminal Phox homology (PX) domain and four SH3 domains. This model characterizes the second SH3 domain of Tks4. 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.

Pssm-ID: 213009 [Multi-domain] Cd Length: 54 Bit Score: 59.28 E-value: 3.06e-11

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....
gi 63055065 371 EEYYTIAEFQTTIPDGISFQAGLKVEVIEKSLSGWWYIQMEDKEGWAPATFIDK 424
Cdd:cd12076   1 EKYTVIYPYTARDQDEINLEKGAVVEVIQKNLEGWWKIRYQGKEGWAPASYLKK 54

Fourth Src homology 3 domain of Tyrosine kinase substrate with five SH3 domains; Tks5, also called SH3 and PX domain-containing protein 2A (SH3PXD2A) or Five SH (FISH), is a scaffolding protein and Src substrate that is localized in podosomes, which are electron-dense structures found in Src-transformed fibroblasts, osteoclasts, macrophages, and some invasive cancer cells. It binds and regulates some members of the ADAMs family of transmembrane metalloproteases, which function as sheddases and mediators of cell and matrix interactions. It is required for podosome formation, degradation of the extracellular matrix, and cancer cell invasion. Tks5 contains an N-terminal Phox homology (PX) domain and five SH3 domains. This model characterizes the fourth SH3 domain of Tks5. 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.

Pssm-ID: 212952 Cd Length: 53 Bit Score: 59.22 E-value: 3.28e-11

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|.
gi 63055065 373 YYTIAEFQTTIPDGISFQAGLKVEVIEKSLSGWWYIQMEDKEGWAPATFID 423
Cdd:cd12019   2 YMTTSAYQKVQDSEISFPAGVEVEVLEKQESGWWYVRFGELEGWAPSHYLE 52

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.

Pssm-ID: 212690 [Multi-domain] Cd Length: 51 Bit Score: 59.01 E-value: 3.62e-11

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|.
gi 63055065 156 QYVVVADYQKQESSEISLSVGQVVDIIEKNESGWWFVSTAEEQ-GWVPATC 205
Cdd:cd00174   1 YARALYDYEAQDDDELSFKKGDIITVLEKDDDGWWEGELNGGReGLFPANY 51

Src homology 3 domain of Type I fungal Myosins; Type I myosins (myosin-I) are actin-dependent motors in endocytic actin structures and actin patches. They play roles in membrane traffic in endocytic and secretory pathways, cell motility, and mechanosensing. Saccharomyces cerevisiae has two myosins-I, Myo3 and Myo5, which are involved in endocytosis and the polarization of the actin cytoskeleton. Myosin-I contains an N-terminal actin-activated ATPase, a phospholipid-binding TH1 (tail homology 1) domain, and a C-terminal extension which includes an F-actin-binding TH2 domain, an SH3 domain, and an acidic peptide that participates in activating the Arp2/3complex. The SH3 domain of myosin-I is required for myosin-I-induced actin polymerization. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

Pssm-ID: 212792 [Multi-domain] Cd Length: 55 Bit Score: 58.94 E-value: 3.90e-11

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....
gi 63055065 156 QYVVVADYQKQESSEISLSVGQVVDIIEKNESGWWFVSTAEE--QGWVPATCLE 207
Cdd:cd11858   1 TYKALYDFAGSVANELSLKKDDIVYIVQKEDNGWWLAKKLDEskEGWVPAAYLE 54

First Src homology 3 domain of Tyrosine kinase substrate with five SH3 domains; Tks5, also called SH3 and PX domain-containing protein 2A (SH3PXD2A) or Five SH (FISH), is a scaffolding protein and Src substrate that is localized in podosomes, which are electron-dense structures found in Src-transformed fibroblasts, osteoclasts, macrophages, and some invasive cancer cells. It binds and regulates some members of the ADAMs family of transmembrane metalloproteases, which function as sheddases and mediators of cell and matrix interactions. It is required for podosome formation, degradation of the extracellular matrix, and cancer cell invasion. Tks5 contains an N-terminal Phox homology (PX) domain and five SH3 domains. This model characterizes the first SH3 domain of Tks5. 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.

Pssm-ID: 213007 [Multi-domain] Cd Length: 53 Bit Score: 58.96 E-value: 4.22e-11

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|.
gi 63055065 225 KYTVIYPYTARDQDEMNLERGAVVEVVQKNLEGWWKIRYQGKEGWAPASYL 275
Cdd:cd12074   1 QYVVVSNYEKQENSEISLQAGEVVDVIEKNESGWWFVSTAEEQGWVPATYL 51

Fourth Src homology 3 domain of Tyrosine kinase substrate with five SH3 domains; Tks5, also called SH3 and PX domain-containing protein 2A (SH3PXD2A) or Five SH (FISH), is a scaffolding protein and Src substrate that is localized in podosomes, which are electron-dense structures found in Src-transformed fibroblasts, osteoclasts, macrophages, and some invasive cancer cells. It binds and regulates some members of the ADAMs family of transmembrane metalloproteases, which function as sheddases and mediators of cell and matrix interactions. It is required for podosome formation, degradation of the extracellular matrix, and cancer cell invasion. Tks5 contains an N-terminal Phox homology (PX) domain and five SH3 domains. This model characterizes the fourth SH3 domain of Tks5. 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.

Pssm-ID: 212952 Cd Length: 53 Bit Score: 58.84 E-value: 4.76e-11

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|.
gi 63055065 157 YVVVADYQKQESSEISLSVGQVVDIIEKNESGWWFVSTAEEQGWVPATCLE 207
Cdd:cd12019   2 YMTTSAYQKVQDSEISFPAGVEVEVLEKQESGWWYVRFGELEGWAPSHYLE 52

Second or C-terminal Src homology 3 domain of the p47phox subunit of NADPH oxidase, also called Neutrophil Cytosolic Factor 1; p47phox, or NCF1, is a cytosolic subunit of the phagocytic NADPH oxidase complex (also called Nox2 or gp91phox), which plays a key role in the ability of phagocytes to defend against bacterial infections. NADPH oxidase catalyzes the transfer of electrons from NADPH to oxygen during phagocytosis forming superoxide and reactive oxygen species. p47phox is required for activation of NADH oxidase and plays a role in translocation. It contains an N-terminal Phox homology (PX) domain, tandem SH3 domains (N-SH3 and C-SH3), a polybasic/autoinhibitory region, and a C-terminal proline-rich region (PRR). This model characterizes the second SH3 domain (or C-SH3) of p47phox. In its inactive state, the tandem SH3 domains interact intramolecularly with the autoinhibitory region; upon activation, the tandem SH3 domains are exposed through a conformational change, resulting in their binding to the PRR of p22phox and the activation of NADPH oxidase. 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.

Pssm-ID: 212955 [Multi-domain] Cd Length: 53 Bit Score: 58.70 E-value: 4.76e-11

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|..
gi 63055065 226 YTVIYPYTARDQDEMNLERGAVVEVVQKNLEGWWKIRYQGKEGWAPASYLKK 277
Cdd:cd12022   2 YITIKAYTAVEEDELTLLEGEAIEVIHKLLDGWWVVRKGEVTGYFPSMYLQK 53

Variant SH3 domain;

Pssm-ID: 434066 [Multi-domain] Cd Length: 49 Bit Score: 58.01 E-value: 6.08e-11

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*....
gi 63055065   228 VIYPYTARDQDEMNLERGAVVEVVQKNLEGWWKIRYQGKEGWAPASYLK 276
Cdd:pfam14604   1 ALYPYEPKDDDELSLQRGDVITVIEESEDGWWEGINTGRTGLVPANYVE 49

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.

Pssm-ID: 214620 [Multi-domain] Cd Length: 56 Bit Score: 58.32 E-value: 6.81e-11

                           10        20        30        40        50
                   ....*....|....*....|....*....|....*....|....*....|....*
gi 63055065    852 YVAVANFEGDEDTS-SFQEGTVFEVREKNSSGWWFCQVLSGApswEGWIPSNYLR 905
Cdd:smart00326   5 VRALYDYTAQDPDElSFKKGDIITVLEKSDDGWWKGRLGRGK---EGLFPSNYVE 56

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.

Pssm-ID: 212758 [Multi-domain] Cd Length: 53 Bit Score: 58.15 E-value: 7.12e-11

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|.
gi 63055065 157 YVVVADYQKQESSEISLSVGQVVDIIEKNESGWWFVSTAEEQGWVPATCLE 207
Cdd:cd11824   2 YSVLYDYTAQEDDELSISKGDVVAVIEKGEDGWWTVERNGQKGLVPGTYLE 52

First Src homology 3 domain of Tyrosine kinase substrate with five SH3 domains; Tks5, also called SH3 and PX domain-containing protein 2A (SH3PXD2A) or Five SH (FISH), is a scaffolding protein and Src substrate that is localized in podosomes, which are electron-dense structures found in Src-transformed fibroblasts, osteoclasts, macrophages, and some invasive cancer cells. It binds and regulates some members of the ADAMs family of transmembrane metalloproteases, which function as sheddases and mediators of cell and matrix interactions. It is required for podosome formation, degradation of the extracellular matrix, and cancer cell invasion. Tks5 contains an N-terminal Phox homology (PX) domain and five SH3 domains. This model characterizes the first SH3 domain of Tks5. 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.

Pssm-ID: 213007 [Multi-domain] Cd Length: 53 Bit Score: 57.41 E-value: 1.22e-10

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....
gi 63055065 852 YVAVANFEGDEDTS-SFQEGTVFEVREKNSSGWWFcqvLSGAPSwEGWIPSNYL 904
Cdd:cd12074   2 YVVVSNYEKQENSEiSLQAGEVVDVIEKNESGWWF---VSTAEE-QGWVPATYL 51

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.

Pssm-ID: 394975 [Multi-domain] Cd Length: 47 Bit Score: 56.83 E-value: 1.93e-10

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*..
gi 63055065   158 VVVADYQKQESSEISLSVGQVVDIIEKNESGWWFV-STAEEQGWVPA 203
Cdd:pfam00018   1 VALYDYTAQEPDELSFKKGDIIIVLEKSEDGWWKGrNKGGKEGLIPS 47

Third Src homology 3 domain of Tyrosine kinase substrate with five SH3 domains; Tks5, also called SH3 and PX domain-containing protein 2A (SH3PXD2A) or Five SH (FISH), is a scaffolding protein and Src substrate that is localized in podosomes, which are electron-dense structures found in Src-transformed fibroblasts, osteoclasts, macrophages, and some invasive cancer cells. It binds and regulates some members of the ADAMs family of transmembrane metalloproteases, which function as sheddases and mediators of cell and matrix interactions. It is required for podosome formation, degradation of the extracellular matrix, and cancer cell invasion. Tks5 contains an N-terminal Phox homology (PX) domain and five SH3 domains. This model characterizes the third SH3 domain of Tks5. 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.

Pssm-ID: 213012 Cd Length: 54 Bit Score: 56.98 E-value: 2.21e-10

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|..
gi 63055065 156 QYVVVADYQKQESSEISLSVGQVVDIIEKNESGWWFVSTAEEQGWVPATCLE 207
Cdd:cd12079   2 EYYTIAEFQSCISDGISFRGGQKAEVIEKNSGGWWYVQIGEKEGWAPSSYID 53

Second Src homology 3 domain of Tyrosine kinase substrate with five SH3 domains; Tks5, also called SH3 and PX domain-containing protein 2A (SH3PXD2A) or Five SH (FISH), is a scaffolding protein and Src substrate that is localized in podosomes, which are electron-dense structures found in Src-transformed fibroblasts, osteoclasts, macrophages, and some invasive cancer cells. It binds and regulates some members of the ADAMs family of transmembrane metalloproteases, which function as sheddases and mediators of cell and matrix interactions. It is required for podosome formation, degradation of the extracellular matrix, and cancer cell invasion. Tks5 contains an N-terminal Phox homology (PX) domain and five SH3 domains. This model characterizes the second SH3 domain of Tks5. 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.

Pssm-ID: 213010 Cd Length: 54 Bit Score: 56.19 E-value: 3.93e-10

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|...
gi 63055065 155 EQYVVVADYQKQESSEISLSVGQVVDIIEKNESGWWFVSTAEEQGWVPATCLE 207
Cdd:cd12077   1 EKYVTVQPYTSQGKDEIGFEKGVTVEVIQKNLEGWWYIRYLGKEGWAPASYLK 53

Third Src homology 3 domain of Tyrosine kinase substrate with four SH3 domains; Tks4, also called SH3 and PX domain-containing protein 2B (SH3PXD2B) or HOFI, is a Src substrate and scaffolding protein that plays an important role in the formation of podosomes and invadopodia, the dynamic actin-rich structures that are related to cell migration and cancer cell invasion. It is required in the formation of functional podosomes, EGF-induced membrane ruffling, and lamellipodia generation. It plays an important role in cellular attachment and cell spreading. Tks4 is essential for the localization of MT1-MMP (membrane-type 1 matrix metalloproteinase) to invadopodia. It contains an N-terminal Phox homology (PX) domain and four SH3 domains. This model characterizes the third SH3 domain of Tks4. 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.

Pssm-ID: 213011 Cd Length: 53 Bit Score: 55.85 E-value: 4.56e-10

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|..
gi 63055065 156 QYVVVADYQKQESSEISLSVGQVVDIIEKNESGWWFVSTAEEQGWVPATCLE 207
Cdd:cd12078   1 EYYTIADFQTTIPDGISFQAGLKVEVIEKNLSGWWYIQIEDKEGWAPATFID 52

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

Pssm-ID: 212700 [Multi-domain] Cd Length: 53 Bit Score: 54.96 E-value: 8.02e-10

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*..
gi 63055065 228 VIYPYTARDQDEMNLERGAVVEVVQKNLEGWWKIRYQGKEGWAPASY 274
Cdd:cd11766   4 VKFNYEAQREDELSLRKGDRVLVLEKSSDGWWRGECNGQVGWFPSNY 50

Src homology 3 domain of Myosins Ie, If, and similar proteins; Myosins Ie (MyoIe) and If (MyoIf) are nonmuscle, unconventional, long tailed, class I myosins containing an N-terminal motor domain and a myosin tail with TH1, TH2, and SH3 domains. MyoIe interacts with the endocytic proteins, dynamin and synaptojanin-1, through its SH3 domain; it may play a role in clathrin-dependent endocytosis. In the kidney, MyoIe is critical for podocyte function and normal glomerular filtration. Mutations in MyoIe is associated with focal segmental glomerulosclerosis, a disease characterized by massive proteinuria and progression to end-stage kidney disease. MyoIf is predominantly expressed in the immune system; it plays a role in immune cell motility and innate immunity. Mutations in MyoIf may be associated with the loss of hearing. The MyoIf gene has also been found to be fused to the MLL (Mixed lineage leukemia) gene in infant acute myeloid leukemias (AML). SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

Pssm-ID: 212761 [Multi-domain] Cd Length: 53 Bit Score: 54.73 E-value: 1.05e-09

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*....
gi 63055065 229 IYPYTARDQDEMNLERGAVVEVVQKNLEGWWKIRYQGKEGWAPASYLKK 277
Cdd:cd11827   5 LYAYDAQDTDELSFNEGDIIEILKEDPSGWWTGRLRGKEGLFPGNYVEK 53

First or N-terminal Src homology 3 domain of the p47phox subunit of NADPH oxidase, also called Neutrophil Cytosolic Factor 1; p47phox, or NCF1, is a cytosolic subunit of the phagocytic NADPH oxidase complex (also called Nox2 or gp91phox), which plays a key role in the ability of phagocytes to defend against bacterial infections. NADPH oxidase catalyzes the transfer of electrons from NADPH to oxygen during phagocytosis forming superoxide and reactive oxygen species. p47phox is required for activation of NADH oxidase and plays a role in translocation. It contains an N-terminal Phox homology (PX) domain, tandem SH3 domains (N-SH3 and C-SH3), a polybasic/autoinhibitory region, and a C-terminal proline-rich region (PRR). This model characterizes the first SH3 domain (or N-SH3) of p47phox. In its inactive state, the tandem SH3 domains interact intramolecularly with the autoinhibitory region; upon activation, the tandem SH3 domains are exposed through a conformational change, resulting in their binding to the PRR of p22phox and the activation of NADPH oxidase. 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.

Pssm-ID: 212954 [Multi-domain] Cd Length: 53 Bit Score: 54.58 E-value: 1.50e-09

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|.
gi 63055065 373 YYTIAEFQTTIPDGISFQAGLKVEVIEKSLSGWWYIQMEDKEGWAPATFID 423
Cdd:cd12021   2 YRAIADYEKSSKSEMALKTGDVVEVVEKSENGWWFCQLKAKRGWVPASYLE 52

Third Src homology 3 domain of Tyrosine kinase substrate with four SH3 domains; Tks4, also called SH3 and PX domain-containing protein 2B (SH3PXD2B) or HOFI, is a Src substrate and scaffolding protein that plays an important role in the formation of podosomes and invadopodia, the dynamic actin-rich structures that are related to cell migration and cancer cell invasion. It is required in the formation of functional podosomes, EGF-induced membrane ruffling, and lamellipodia generation. It plays an important role in cellular attachment and cell spreading. Tks4 is essential for the localization of MT1-MMP (membrane-type 1 matrix metalloproteinase) to invadopodia. It contains an N-terminal Phox homology (PX) domain and four SH3 domains. This model characterizes the third SH3 domain of Tks4. 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.

Pssm-ID: 213011 Cd Length: 53 Bit Score: 54.31 E-value: 1.94e-09

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|...
gi 63055065 225 KYTVIYPYTARDQDEMNLERGAVVEVVQKNLEGWWKIRYQGKEGWAPASYLKK 277
Cdd:cd12078   1 EYYTIADFQTTIPDGISFQAGLKVEVIEKNLSGWWYIQIEDKEGWAPATFIDK 53

Second or C-terminal Src homology 3 domain of NADPH oxidase (Nox) Organizing protein 1; Nox Organizing protein 1 (NoxO1) is a critical regulator of enzyme kinetics of the nonphagocytic NADPH oxidase Nox1, which catalyzes the transfer of electrons from NADPH to molecular oxygen to form superoxide. Nox1 is expressed in colon, stomach, uterus, prostate, and vascular smooth muscle cells. NoxO1 is involved in targeting activator subunits (such as NoxA1) to Nox1. It is co-localized with Nox1 in the membranes of resting cells and directs the subcellular localization of Nox1. NoxO1 contains an N-terminal Phox homology (PX) domain, tandem SH3 domains (N-SH3 and C-SH3), and a C-terminal proline-rich region (PRR). This model characterizes the second SH3 domain (or C-SH3) of NoxO1. The tandem SH3 domains of NoxO1 interact with the PRR of p22phox, which also complexes with Nox1. 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.

Pssm-ID: 212957 Cd Length: 53 Bit Score: 53.88 E-value: 2.47e-09

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|.
gi 63055065 156 QYVVVADYQKQESSEISLSVGQVVDIIEKNESGWWFVSTAEEQGWVPATCL 206
Cdd:cd12024   1 LYYATRAYEAQKEDELSVPAGVVVEVLQKSDNGWWLIRYNGRAGYVPSMYL 51

Src homology 3 domain of Type I fungal Myosins; Type I myosins (myosin-I) are actin-dependent motors in endocytic actin structures and actin patches. They play roles in membrane traffic in endocytic and secretory pathways, cell motility, and mechanosensing. Saccharomyces cerevisiae has two myosins-I, Myo3 and Myo5, which are involved in endocytosis and the polarization of the actin cytoskeleton. Myosin-I contains an N-terminal actin-activated ATPase, a phospholipid-binding TH1 (tail homology 1) domain, and a C-terminal extension which includes an F-actin-binding TH2 domain, an SH3 domain, and an acidic peptide that participates in activating the Arp2/3complex. The SH3 domain of myosin-I is required for myosin-I-induced actin polymerization. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

Pssm-ID: 212792 [Multi-domain] Cd Length: 55 Bit Score: 53.16 E-value: 4.35e-09

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|...
gi 63055065 226 YTVIYPYTARDQDEMNLERGAVVEVVQKNLEGWW--KIRYQGKEGWAPASYLK 276
Cdd:cd11858   2 YKALYDFAGSVANELSLKKDDIVYIVQKEDNGWWlaKKLDESKEGWVPAAYLE 54

The phosphoinositide binding Phox Homology domain of Sorting Nexin 13; The PX domain is a phosphoinositide (PI) binding module present in many proteins with diverse functions. Sorting nexins (SNXs) make up the largest group among PX domain containing proteins. They are involved in regulating membrane traffic and protein sorting in the endosomal system. The PX domain of SNXs binds PIs and targets the protein to PI-enriched membranes. SNXs differ from each other in PI-binding specificity and affinity, and the presence of other protein-protein interaction domains, which help determine subcellular localization and specific function in the endocytic pathway. SNX13, also called RGS-PX1, contains an N-terminal PXA domain, a regulator of G protein signaling (RGS) domain, a PX domain, and a C-terminal domain that is conserved in some SNXs. It specifically binds to the stimulatory subunit of the heterotrimeric G protein G(alpha)s, serving as its GTPase activating protein, through the RGS domain. It preferentially binds phosphatidylinositol-3-phosphate (PI3P) through the PX domain and is localized in early endosomes. SNX13 is involved in endosomal sorting of EGFR into multivesicular bodies (MVB) for delivery to the lysosome.

Pssm-ID: 132783 Cd Length: 120 Bit Score: 54.97 E-value: 4.71e-09

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 63055065  26 VYIIRVT--WSSGATEA--IYRRYSKFFDLQMQMLDKFpmeggqkdPKQRIIPFlPGKILFRRSHiRDVAVKRLIPIDEY 101
Cdd:cd06873  24 VYAISVTriYPNGQEESwhVYRRYSDFHDLHMRLKEKF--------PNLSKLSF-PGKKTFNNLD-RAFLEKRRKMLNQY 93


                ....*.
gi 63055065 102 CKALIQ 107
Cdd:cd06873  94 LQSLLN 99

Third Src homology 3 domain of Tyrosine kinase substrate (Tks) proteins; Tks proteins are Src substrates and scaffolding proteins that play important roles in the formation of podosomes and invadopodia, the dynamic actin-rich structures that are related to cell migration and cancer cell invasion. Vertebrates contain two Tks proteins, Tks4 (Tyr kinase substrate with four SH3 domains) and Tks5 (Tyr kinase substrate with five SH3 domains), which display partially overlapping but non-redundant functions. Both associate with the ADAMs family of transmembrane metalloproteases, which function as sheddases and mediators of cell and matrix interactions. Tks5 interacts with N-WASP and Nck, while Tks4 is essential for the localization of MT1-MMP (membrane-type 1 matrix metalloproteinase) to invadopodia. Tks proteins contain an N-terminal Phox homology (PX) domain and four or five SH3 domains. This model characterizes the third SH3 domain of Tks 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.

Pssm-ID: 212950 Cd Length: 53 Bit Score: 52.84 E-value: 5.14e-09

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*.
gi 63055065 852 YVAVANFE-GDEDTSSFQEGTVFEVREKNSSGWWFCQVlsgaPSWEGWIPSNYLRK 906
Cdd:cd12017   2 YFTIGEFQaTIQDGISFQKGQKVEVIDKNPSGWWYVKI----DGKEGWAPSSYIEK 53

First Src homology 3 domain (or SH3A) of Intersectin; Intersectins (ITSNs) are adaptor proteins that function in exo- and endocytosis, actin cytoskeletal reorganization, and signal transduction. They are essential for initiating clathrin-coated pit formation. They bind to many proteins through their multidomain structure and facilitate the assembly of multimeric complexes. Vertebrates contain two ITSN proteins, ITSN1 and ITSN2, which exist in alternatively spliced short and long isoforms. The short isoforms contain two Eps15 homology domains (EH1 and EH2), a coiled-coil region and five SH3 domains (SH3A-E), while the long isoforms, in addition, contain RhoGEF (also called Dbl-homologous or DH), Pleckstrin homology (PH) and C2 domains. ITSN1 and ITSN2 are both widely expressed, with variations depending on tissue type and stage of development. The first SH3 domain (or SH3A) of ITSN1 has been shown to bind many proteins including Sos1, dynamin1/2, CIN85, c-Cbl, PI3K-C2, SHIP2, N-WASP, and CdGAP, among others. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

Pssm-ID: 212770 [Multi-domain] Cd Length: 55 Bit Score: 52.75 E-value: 5.39e-09

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*
gi 63055065 225 KYTVIYPYTARDQDEMNLERGAVVEV--VQKNLEGWWKIRYQGKEGWAPASYLKK 277
Cdd:cd11836   1 KYRALYAFEARNPDEISFQPGDIIQVdeSQVAEPGWLAGELKGKTGWFPANYVEK 55

First Src homology 3 domain (or SH3A) of Intersectin-2; Intersectin-2 (ITSN2) is an adaptor protein that functions in exo- and endocytosis, actin cytoskeletal reorganization, and signal transduction. It plays a role in clathrin-coated pit (CCP) formation. It binds to many proteins through its multidomain structure and facilitate the assembly of multimeric complexes. ITSN2 also functions as a specific GEF for Cdc42 activation in epithelial morphogenesis, and is required in mitotic spindle orientation. It exists in alternatively spliced short and long isoforms. The short isoform contains two Eps15 homology domains (EH1 and EH2), a coiled-coil region and five SH3 domains (SH3A-E), while the long isoform, in addition, contains RhoGEF (also called Dbl-homologous or DH), Pleckstrin homology (PH) and C2 domains. The first SH3 domain (or SH3A) of ITSN2 is expected to bind many protein partners, similar to ITSN1 which has been shown to bind Sos1, dynamin1/2, CIN85, c-Cbl, PI3K-C2, SHIP2, N-WASP, and CdGAP, among others. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

Pssm-ID: 212921 [Multi-domain] Cd Length: 57 Bit Score: 52.95 E-value: 5.42e-09

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....
gi 63055065 226 YTVIYPYTARDQDEMNLERGAVVEVVQKNL--EGWWKIRYQGKEGWAPASYLKK 277
Cdd:cd11988   4 YRALYPFEARNHDEMSFNAGDIIQVDEKTVgePGWLYGSFQGNFGWFPCNYVEK 57

First or N-terminal Src homology 3 domain of the p47phox subunit of NADPH oxidase, also called Neutrophil Cytosolic Factor 1; p47phox, or NCF1, is a cytosolic subunit of the phagocytic NADPH oxidase complex (also called Nox2 or gp91phox), which plays a key role in the ability of phagocytes to defend against bacterial infections. NADPH oxidase catalyzes the transfer of electrons from NADPH to oxygen during phagocytosis forming superoxide and reactive oxygen species. p47phox is required for activation of NADH oxidase and plays a role in translocation. It contains an N-terminal Phox homology (PX) domain, tandem SH3 domains (N-SH3 and C-SH3), a polybasic/autoinhibitory region, and a C-terminal proline-rich region (PRR). This model characterizes the first SH3 domain (or N-SH3) of p47phox. In its inactive state, the tandem SH3 domains interact intramolecularly with the autoinhibitory region; upon activation, the tandem SH3 domains are exposed through a conformational change, resulting in their binding to the PRR of p22phox and the activation of NADPH oxidase. 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.

Pssm-ID: 212954 [Multi-domain] Cd Length: 53 Bit Score: 52.65 E-value: 6.90e-09

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|.
gi 63055065 226 YTVIYPYTARDQDEMNLERGAVVEVVQKNLEGWWKIRYQGKEGWAPASYLK 276
Cdd:cd12021   2 YRAIADYEKSSKSEMALKTGDVVEVVEKSENGWWFCQLKAKRGWVPASYLE 52

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.

Pssm-ID: 212690 [Multi-domain] Cd Length: 51 Bit Score: 52.47 E-value: 6.99e-09

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|...
gi 63055065 852 YVAVANFEGDEDTS-SFQEGTVFEVREKNSSGWWFCQVLSGApswEGWIPSNY 903
Cdd:cd00174   2 ARALYDYEAQDDDElSFKKGDIITVLEKDDDGWWEGELNGGR---EGLFPANY 51

Src Homology 3 domain of Nephrocystin (or Nephrocystin-1); Nephrocystin contains an SH3 domain involved in signaling pathways that regulate cell adhesion and cytoskeletal organization. It is a protein that in humans is associated with juvenile nephronophthisis, an inherited kidney disease characterized by renal fibrosis that lead to chronic renal failure in children. It is localized in cell-cell junctions in renal duct cells, and is known to interact with Ack1, an activated Cdc42-associated kinase. 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.

Pssm-ID: 212704 [Multi-domain] Cd Length: 54 Bit Score: 51.93 E-value: 9.66e-09

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|..
gi 63055065 157 YVVVADYQKQESSEISLSVGQVVDIIEKNESGWWFVSTAE-EQGWVPATCLE 207
Cdd:cd11770   2 YEALSDFQAEQEGDLSFKKGEVLRIISKRADGWWLAENSKgNRGLVPKTYLK 53

Second Src Homology 3 domain of Nck1 adaptor protein; Nck1 (also called Nckalpha) plays a crucial role in connecting signaling pathways of tyrosine kinase receptors and important effectors in actin dynamics and cytoskeletal remodeling. It binds and activates RasGAP, resulting in the downregulation of Ras. It is also involved in the signaling of endothilin-mediated inhibition of cell migration. Nck adaptor proteins regulate actin cytoskeleton dynamics by linking proline-rich effector molecules to protein tyrosine kinases and phosphorylated signaling intermediates. They contain three SH3 domains and a C-terminal SH2 domain. They function downstream of the PDGFbeta receptor and are involved in Rho GTPase signaling and actin dynamics. Vertebrates contain two Nck adaptor proteins: Nck1 (also called Nckalpha) and Nck2, which show partly overlapping functions but also bind distinct targets. The second SH3 domain of Nck appears to prefer ligands containing the APxxPxR motif. SH3 domains are protein interaction domains that usually bind to proline-rich ligands with moderate affinity and selectivity, preferentially a PxxP motif. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

Pssm-ID: 212834 [Multi-domain] Cd Length: 55 Bit Score: 51.96 E-value: 1.14e-08

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*...
gi 63055065 228 VIYPYTARDQDEMNLERGAVVEVVQKNLEGWWKIRYQGKEGWAPASYL 275
Cdd:cd11901   6 VKFNYTAEREDELSLVKGTKVIVMEKCSDGWWRGSYNGQVGWFPSNYV 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.

Pssm-ID: 212991 [Multi-domain] Cd Length: 58 Bit Score: 51.87 E-value: 1.26e-08

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*
gi 63055065 226 YTVIYPYTARDQDEMNLERGAVVEVVQKNL-----EGWWKIRYQGKEGWAPASYL 275
Cdd:cd12058   2 WTALYDYEASGEDELSLRRGDVVEVLSQDAavsgdDGWWAGKIRHRLGIFPANYV 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.

Pssm-ID: 429575 [Multi-domain] Cd Length: 54 Bit Score: 51.44 E-value: 1.83e-08

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|.
gi 63055065   157 YVVVADYQKQESSEISLSVGQVVDIIEKNESGWWFVSTAEEQGWVPATCLE 207
Cdd:pfam07653   2 GRVIFDYVGTDKNGLTLKKGDVVKVLGKDNDGWWEGETGGRVGLVPSTAVE 52

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.

Pssm-ID: 212757 [Multi-domain] Cd Length: 53 Bit Score: 51.19 E-value: 2.00e-08

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*...
gi 63055065 227 TVIYPYTARDQDEMNLERGAVVEVVQKNLEGWWKIRYQGKEGWAPASY 274
Cdd:cd11823   3 KALYSYTANREDELSLQPGDIIEVHEKQDDGWWLGELNGKKGIFPATY 50

First Src homology 3 domain of Tyrosine kinase substrate (Tks) proteins; Tks proteins are Src substrates and scaffolding proteins that play important roles in the formation of podosomes and invadopodia, the dynamic actin-rich structures that are related to cell migration and cancer cell invasion. Vertebrates contain two Tks proteins, Tks4 (Tyr kinase substrate with four SH3 domains) and Tks5 (Tyr kinase substrate with five SH3 domains), which display partially overlapping but non-redundant functions. Both associate with the ADAMs family of transmembrane metalloproteases, which function as sheddases and mediators of cell and matrix interactions. Tks5 interacts with N-WASP and Nck, while Tks4 is essential for the localization of MT1-MMP (membrane-type 1 matrix metalloproteinase) to invadopodia. Tks proteins contain an N-terminal Phox homology (PX) domain and four or five SH3 domains. This model characterizes the first SH3 domain of Tks 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.

Pssm-ID: 212948 Cd Length: 53 Bit Score: 50.50 E-value: 3.62e-08

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*.
gi 63055065 852 YVAVANFEGDEDTS-SFQEGTVFEVREKNSSGWWFCQVlsgaPSWEGWIPSNYLRK 906
Cdd:cd12015   2 YVVVADYKKQQPNEiSLRAGDVVDVIEKNENGWWFVSL----EDEQGWVPATYLEP 53

Src Homology 3 domain of Pak Interactive eXchange factors; PIX proteins are Rho guanine nucleotide exchange factors (GEFs), which activate small GTPases by exchanging bound GDP for free GTP. They act as GEFs for both Cdc42 and Rac 1, and have been implicated in cell motility, adhesion, neurite outgrowth, and cell polarity. Vertebrates contain two proteins from the PIX subfamily, alpha-PIX and beta-PIX. Alpha-PIX, also called ARHGEF6, is localized in dendritic spines where it regulates spine morphogenesis. Mutations in the ARHGEF6 gene cause X-linked intellectual disability in humans. Beta-PIX play roles in regulating neuroendocrine exocytosis, focal adhesion maturation, cell migration, synaptic vesicle localization, and insulin secretion. PIX proteins contain an N-terminal SH3 domain followed by RhoGEF (also called Dbl-homologous or DH) and Pleckstrin Homology (PH) domains, and a C-terminal leucine-zipper domain for dimerization. The SH3 domain of PIX binds to an atypical PxxxPR motif in p21-activated kinases (PAKs) with high affinity. The binding of PAKs to PIX facilitate the localization of PAKs to focal complexes and also localizes PAKs to PIX targets Cdc43 and Rac, leading to the activation of PAKs. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

Pssm-ID: 212810 [Multi-domain] Cd Length: 53 Bit Score: 50.39 E-value: 3.64e-08

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|..
gi 63055065 225 KYTVIYPYTARDQDEMNLERGAVVEVVQKNLEGWWKIRYQGKEGWAPASYLK 276
Cdd:cd11877   1 LVRAKFNFEGTNEDELSFDKGDIITVTQVVEGGWWEGTLNGKTGWFPSNYVK 52

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.

Pssm-ID: 429575 [Multi-domain] Cd Length: 54 Bit Score: 50.29 E-value: 3.67e-08

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|...
gi 63055065   225 KYTVIYPYTARDQDEMNLERGAVVEVVQKNLEGWWKIRYQGKEGWAPASYLKK 277
Cdd:pfam07653   1 YGRVIFDYVGTDKNGLTLKKGDVVKVLGKDNDGWWEGETGGRVGLVPSTAVEE 53

First Src homology 3 domain of Tyrosine kinase substrate with four SH3 domains; Tks4, also called SH3 and PX domain-containing protein 2B (SH3PXD2B) or HOFI, is a Src substrate and scaffolding protein that plays an important role in the formation of podosomes and invadopodia, the dynamic actin-rich structures that are related to cell migration and cancer cell invasion. It is required in the formation of functional podosomes, EGF-induced membrane ruffling, and lamellipodia generation. It plays an important role in cellular attachment and cell spreading. Tks4 is essential for the localization of MT1-MMP (membrane-type 1 matrix metalloproteinase) to invadopodia. It contains an N-terminal Phox homology (PX) domain and four SH3 domains. This model characterizes the first SH3 domain of Tks4. 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.

Pssm-ID: 213008 Cd Length: 55 Bit Score: 50.46 E-value: 4.39e-08

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....
gi 63055065 852 YVAVANFEGDEDTS-SFQEGTVFEVREKNSSGWWFcqvLSGAPSwEGWIPSNYL 904
Cdd:cd12075   3 YVVVANYQKQESSEiSLYVGQVVDIIEKNESGWWF---VSTADE-QGWVPATCL 52

Src homology 3 domain of ARHGEF9-like Rho guanine nucleotide exchange factors; Members of this family contain a SH3 domain followed by RhoGEF (also called Dbl-homologous or DH) and Pleckstrin Homology (PH) domains. They include the Rho guanine nucleotide exchange factors ARHGEF9, ASEF (also called ARHGEF4), ASEF2, and similar proteins. GEFs activate small GTPases by exchanging bound GDP for free GTP. ARHGEF9 specifically activates Cdc42, while both ASEF and ASEF2 can activate Rac1 and Cdc42. ARHGEF9 is highly expressed in the brain and it interacts with gephyrin, a postsynaptic protein associated with GABA and glycine receptors. ASEF plays a role in angiogenesis and cell migration. ASEF2 is important in cell migration and adhesion dynamics. ASEF exists in an autoinhibited form and is activated upon binding of the tumor suppressor APC (adenomatous polyposis coli), leading to the activation of Rac1 or Cdc42. In its autoinhibited form, the SH3 domain of ASEF forms an extensive interface with the DH and PH domains, blocking the Rac 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.

Pssm-ID: 212762 [Multi-domain] Cd Length: 53 Bit Score: 50.07 E-value: 4.75e-08

                        10        20        30
                ....*....|....*....|....*....|....*....
gi 63055065 384 PDGISFQAGLKVEVIEKSLSGWWYIQMEDKEGWAPATFI 422
Cdd:cd11828  13 PEELGFKAGDVIEVLDMSDKDWWWGSIRDEEGWFPASFV 51

Fourth Src homology 3 domain (or SH3D) 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 fourth SH3 domain (or SH3D) of ITSN1 has been shown to bind SHIP2, Numb, CdGAP, and N-WASP. 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.

Pssm-ID: 212773 [Multi-domain] Cd Length: 58 Bit Score: 50.03 E-value: 5.24e-08

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*.
gi 63055065 227 TVIYPYTARDQDEMNLERGAVVEVVQKNLEGWWKIRYQGKE-----GWAPASYLKK 277
Cdd:cd11839   3 QVIAPFTATAENQLSLAVGQLVLVRKKSPSGWWEGELQARGkkrqiGWFPANYVKL 58

Src Homology 3 domain of SH3 domain-containing protein 21 (SH3D21) and similar proteins; N-terminal SH3 domain of the uncharacterized protein SH3 domain-containing protein 21, and similar uncharacterized domains, it belongs to the CD2AP-like_3 subfamily of proteins. The CD2AP-like_3 subfamily is composed of the third SH3 domain (SH3C) 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. SH3C of both proteins have been shown to bind to 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.

Pssm-ID: 213018 [Multi-domain] Cd Length: 55 Bit Score: 49.77 E-value: 6.51e-08

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*....
gi 63055065 225 KYTVIYPYTARDQDEMNLERGAVVEVVQKNLE--GWWKIRYQGKEGWAP 271
Cdd:cd12142   1 YCRVLFDYNPVAPDELALKKGDVIEVISKETEdeGWWEGELNGRRGFFP 49

Fifth (C-terminal) Src homology 3 domain of Tyrosine kinase substrate with five SH3 domains; Tks5, also called SH3 and PX domain-containing protein 2A (SH3PXD2A) or Five SH (FISH), is a scaffolding protein and Src substrate that is localized in podosomes, which are electron-dense structures found in Src-transformed fibroblasts, osteoclasts, macrophages, and some invasive cancer cells. It binds and regulates some members of the ADAMs family of transmembrane metalloproteases, which function as sheddases and mediators of cell and matrix interactions. It is required for podosome formation, degradation of the extracellular matrix, and cancer cell invasion. Tks5 contains an N-terminal Phox homology (PX) domain and five SH3 domains. This model characterizes the fifth (C-terminal) SH3 domain of Tks5. 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.

Pssm-ID: 212953 Cd Length: 57 Bit Score: 49.19 E-value: 1.14e-07

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*.
gi 63055065 373 YYTIAEFQTTiPDGISFQAGLKVEVIEKSLSGWWYIQMED----KEGWAPATFIDK 424
Cdd:cd12020   2 YVSIADYEGD-EETAGFQEGVSMEVLEKNPNGWWYCQILDgvkpFKGWVPSNYLEK 56

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.

Pssm-ID: 214620 [Multi-domain] Cd Length: 56 Bit Score: 49.07 E-value: 1.33e-07

                           10        20        30        40        50
                   ....*....|....*....|....*....|....*....|....*....|....*
gi 63055065    369 VEEEYYTIAEFQTTIPDGISFQAGLKVEVIEKSLSGWWYIQMED-KEGWAPATFI 422
Cdd:smart00326   1 EGPQVRALYDYTAQDPDELSFKKGDIITVLEKSDDGWWKGRLGRgKEGLFPSNYV 55

Second Src Homology 3 domain of Nck2 adaptor protein; Nck2 (also called Nckbeta or Growth factor receptor-bound protein 4, Grb4) plays a crucial role in connecting signaling pathways of tyrosine kinase receptors and important effectors in actin dynamics and cytoskeletal remodeling. It binds neuronal signaling proteins such as ephrinB and Disabled-1 (Dab-1) exclusively. Nck adaptor proteins regulate actin cytoskeleton dynamics by linking proline-rich effector molecules to protein tyrosine kinases and phosphorylated signaling intermediates. They contain three SH3 domains and a C-terminal SH2 domain. They function downstream of the PDGFbeta receptor and are involved in Rho GTPase signaling and actin dynamics. Vertebrates contain two Nck adaptor proteins: Nck1 (also called Nckalpha) and Nck2, which show partly overlapping functions but also bind distinct targets. The second SH3 domain of Nck appears to prefer ligands containing the APxxPxR motif. SH3 domains are protein interaction domains that usually bind to proline-rich ligands with moderate affinity and selectivity, preferentially a PxxP motif. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

Pssm-ID: 212835 [Multi-domain] Cd Length: 55 Bit Score: 48.85 E-value: 1.45e-07

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*...
gi 63055065 228 VIYPYTARDQDEMNLERGAVVEVVQKNLEGWWKIRYQGKEGWAPASYL 275
Cdd:cd11902   5 VKFAYVAEREDELSLVKGSRVTVMEKCSDGWWRGSYNGQIGWFPSNYV 52

Src homology 3 domain of Protein arginine N-methyltransferase 2; PRMT2, also called HRMT1L1, belongs to the arginine methyltransferase protein family. It functions as a coactivator to both estrogen receptor alpha (ER-alpha) and androgen receptor (AR), presumably through arginine methylation. The ER-alpha transcription factor is involved in cell proliferation, differentiation, morphogenesis, and apoptosis, and is also implicated in the development and progression of breast cancer. PRMT2 and its variants are upregulated in breast cancer cells and may be involved in modulating the ER-alpha signaling pathway during formation of breast cancer. PRMT2 also plays a role in regulating the function of E2F transcription factors, which are critical cell cycle regulators, by binding to the retinoblastoma gene product (RB). It contains an N-terminal SH3 domain and an AdoMet binding 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.

Pssm-ID: 212740 [Multi-domain] Cd Length: 53 Bit Score: 48.93 E-value: 1.48e-07

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|
gi 63055065 226 YTVIYPYTARDQDEMNLERGAVVEVVQKNLEGWWKIRYQGKEGWAPASYL 275
Cdd:cd11806   2 YVAIADFVATDDSQLSFESGDKLLVLRKPSVDWWWAEHNGCCGYIPASHL 51

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.

Pssm-ID: 212727 [Multi-domain] Cd Length: 55 Bit Score: 48.87 E-value: 1.59e-07

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|
gi 63055065 228 VIYPYTARDQDEMNLERGAVVEVVQKNLEGWW---KIRyQGKEGWAPASY 274
Cdd:cd11793   4 CVHAYTAQQPDELTLEEGDVVNVLRKMPDGWYegeRLR-DGERGWFPSSY 52

Third Src homology 3 domain of Tyrosine kinase substrate with five SH3 domains; Tks5, also called SH3 and PX domain-containing protein 2A (SH3PXD2A) or Five SH (FISH), is a scaffolding protein and Src substrate that is localized in podosomes, which are electron-dense structures found in Src-transformed fibroblasts, osteoclasts, macrophages, and some invasive cancer cells. It binds and regulates some members of the ADAMs family of transmembrane metalloproteases, which function as sheddases and mediators of cell and matrix interactions. It is required for podosome formation, degradation of the extracellular matrix, and cancer cell invasion. Tks5 contains an N-terminal Phox homology (PX) domain and five SH3 domains. This model characterizes the third SH3 domain of Tks5. 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.

Pssm-ID: 213012 Cd Length: 54 Bit Score: 48.50 E-value: 1.72e-07

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|...
gi 63055065 225 KYTVIYPYTARDQDEMNLERGAVVEVVQKNLEGWWKIRYQGKEGWAPASYLKK 277
Cdd:cd12079   2 EYYTIAEFQSCISDGISFRGGQKAEVIEKNSGGWWYVQIGEKEGWAPSSYIDK 54

Src homology 3 domain of DBL's Big Sister (DBS), a guanine nucleotide exchange factor; DBS, also called MCF2L (MCF2-transforming sequence-like protein) or OST, is a Rho GTPase guanine nucleotide exchange factor (RhoGEF), facilitating the exchange of GDP and GTP. It was originally isolated from a cDNA screen for sequences that cause malignant growth. It plays roles in regulating clathrin-mediated endocytosis and cell migration through its activation of Rac1 and Cdc42. Depending on cell type, DBS can also activate RhoA and RhoG. DBS contains a Sec14-like domain, spectrin-like repeats, a RhoGEF [or Dbl homology (DH)] domain, a Pleckstrin homology (PH) domain, and an 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.

Pssm-ID: 212791 Cd Length: 55 Bit Score: 47.67 E-value: 3.40e-07

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|..
gi 63055065 157 YVVVADYQKQESSEISLSVGQVVDIIEKNESGWWFVS--TAEEQGWVPATCL 206
Cdd:cd11857   2 YTVVADYEKGGPDDLTVKSGDLVQLIHEGDEGQWLVKnlSTRKEGWVPAANL 53

Fourth Src homology 3 domain of Tyrosine kinase substrate with five SH3 domains; Tks5, also called SH3 and PX domain-containing protein 2A (SH3PXD2A) or Five SH (FISH), is a scaffolding protein and Src substrate that is localized in podosomes, which are electron-dense structures found in Src-transformed fibroblasts, osteoclasts, macrophages, and some invasive cancer cells. It binds and regulates some members of the ADAMs family of transmembrane metalloproteases, which function as sheddases and mediators of cell and matrix interactions. It is required for podosome formation, degradation of the extracellular matrix, and cancer cell invasion. Tks5 contains an N-terminal Phox homology (PX) domain and five SH3 domains. This model characterizes the fourth SH3 domain of Tks5. 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.

Pssm-ID: 212952 Cd Length: 53 Bit Score: 47.67 E-value: 3.42e-07

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|
gi 63055065 226 YTVIYPYTARDQDEMNLERGAVVEVVQKNLEGWWKIRYQGKEGWAPASYL 275
Cdd:cd12019   2 YMTTSAYQKVQDSEISFPAGVEVEVLEKQESGWWYVRFGELEGWAPSHYL 51

Third Src Homology 3 domain (SH3C) of CD2-associated protein and similar proteins; This subfamily is composed of the third SH3 domain (SH3C) 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. SH3C of both proteins have been shown to bind to 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.

Pssm-ID: 212808 [Multi-domain] Cd Length: 55 Bit Score: 47.73 E-value: 3.81e-07

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*....
gi 63055065 225 KYTVIYPYTARDQDEMNLERGAVVEVVQKNLE--GWWKIRYQGKEGWAP 271
Cdd:cd11875   1 KARVLFDYEAENEDELTLREGDIVTILSKDCEdkGWWKGELNGKRGVFP 49

Src homology 3 domain of Abl Interactor 2; Abi2 is highly expressed in the brain and eye. It regulates actin cytoskeletal reorganization at adherens junctions and dendritic spines, which is important in cell morphogenesis, migration, and cognitive function. Mice deficient with Abi2 show defects in orientation and migration of lens fibers, neuronal migration, dendritic spine morphology, as well as deficits in learning and memory. 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. 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.

Pssm-ID: 212905 [Multi-domain] Cd Length: 61 Bit Score: 47.70 E-value: 4.03e-07

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*..
gi 63055065 224 EKYTVIYPYTARDQDEMNLERGAVVEVVQKNLEGWWKIRYQGKEGWAPASYLKKNSG 280
Cdd:cd11972   3 EKVVAIYDYTKDKEDELSFQEGAIIYVIKKNDDGWYEGVMNGVTGLFPGNYVESIMH 59

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.

Pssm-ID: 212774 [Multi-domain] Cd Length: 53 Bit Score: 47.41 E-value: 4.38e-07

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*...
gi 63055065 229 IYPYTARDQDEMNLERGAVVEVVQKNLEGWWKIRYQGKEGWAPASYLK 276
Cdd:cd11840   5 LFPYTAQNEDELSFQKGDIINVLSKDDPDWWRGELNGQTGLFPSNYVE 52

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.

Pssm-ID: 212706 [Multi-domain] Cd Length: 53 Bit Score: 47.29 E-value: 4.56e-07

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|
gi 63055065 226 YTVIYPYTARDQDEMNLERGAVVEVVQKNLEGWWKIRYQGKEGWAPASYL 275
Cdd:cd11772   2 FRALYDYEAQHPDELSFEEGDLLYISDKSDPNWWKATCGGKTGLIPSNYV 51

Second Src Homology 3 domain (SH3B) of CD2-associated protein and similar proteins; This subfamily is composed of the second SH3 domain (SH3B) 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. SH3B of both proteins have been shown to bind to Cbl. In the case of CD2AP, its SH3B binds to Cbl at a site distinct from the c-Cbl/SH3A binding site. The CIN85 SH3B also binds 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.

Pssm-ID: 212807 [Multi-domain] Cd Length: 53 Bit Score: 47.33 E-value: 4.87e-07

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*....
gi 63055065 228 VIYPYTARDQDEMNLERGAVVEVVQKNLEGWWKIRYQGKEGWAPASYLK 276
Cdd:cd11874   4 VLFSYTPQNEDELELKVGDTIEVLGEVEEGWWEGKLNGKVGVFPSNFVK 52

C-terminal (or second) Src homology 3 domain of VAV1 protein; VAV1 is expressed predominantly in the hematopoietic system and it plays an important role in the development and activation of B and T cells. It is activated by tyrosine phosphorylation to function as a guanine nucleotide exchange factor (GEF) for Rho GTPases following cell surface receptor activation, triggering various effects such as cytoskeletal reorganization, transcription regulation, cell cycle progression, and calcium mobilization. It also serves as a scaffold protein and has been shown to interact with Ku70, Socs1, Janus kinase 2, SIAH2, S100B, Abl gene, ZAP-70, SLP76, and Syk, among others. 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 C-terminal SH3 domain of Vav1 interacts with a wide variety of proteins including cytoskeletal regulators (zyxin), RNA-binding proteins (Sam68), transcriptional regulators, viral proteins, and dynamin 2. 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.

Pssm-ID: 212909 [Multi-domain] Cd Length: 54 Bit Score: 47.25 E-value: 6.05e-07

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*....
gi 63055065 230 YPYTARDQDEMNLERGAVVEVV-QKNLEGWWKIRYQGKEGWAPASYLKK 277
Cdd:cd11976   6 YDFCARDRSELSLKEGDIIKILnKKGQQGWWRGEIYGRVGWFPANYVEE 54

Second or C-terminal Src homology 3 domain of the p47phox subunit of NADPH oxidase, also called Neutrophil Cytosolic Factor 1; p47phox, or NCF1, is a cytosolic subunit of the phagocytic NADPH oxidase complex (also called Nox2 or gp91phox), which plays a key role in the ability of phagocytes to defend against bacterial infections. NADPH oxidase catalyzes the transfer of electrons from NADPH to oxygen during phagocytosis forming superoxide and reactive oxygen species. p47phox is required for activation of NADH oxidase and plays a role in translocation. It contains an N-terminal Phox homology (PX) domain, tandem SH3 domains (N-SH3 and C-SH3), a polybasic/autoinhibitory region, and a C-terminal proline-rich region (PRR). This model characterizes the second SH3 domain (or C-SH3) of p47phox. In its inactive state, the tandem SH3 domains interact intramolecularly with the autoinhibitory region; upon activation, the tandem SH3 domains are exposed through a conformational change, resulting in their binding to the PRR of p22phox and the activation of NADPH oxidase. 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.

Pssm-ID: 212955 [Multi-domain] Cd Length: 53 Bit Score: 46.76 E-value: 6.79e-07

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|..
gi 63055065 373 YYTIAEFQTTIPDGISFQAGLKVEVIEKSLSGWWYIQMEDKEGWAPATFIDK 424
Cdd:cd12022   2 YITIKAYTAVEEDELTLLEGEAIEVIHKLLDGWWVVRKGEVTGYFPSMYLQK 53

Src homology 3 domain of CAS (Crk-Associated Substrate) scaffolding proteins; CAS proteins function as molecular scaffolds to regulate protein complexes that are involved in many cellular processes including migration, chemotaxis, apoptosis, differentiation, and progenitor cell function. They mediate the signaling of integrins at focal adhesions where they localize, and thus, regulate cell invasion and survival. Over-expression of these proteins is implicated in poor prognosis, increased metastasis, and resistance to chemotherapeutics in many cancers such as breast, lung, melanoma, and glioblastoma. CAS proteins have also been linked to the pathogenesis of inflammatory disorders, Alzheimer's, Parkinson's, and developmental defects. They share a common domain structure that includes an N-terminal SH3 domain, an unstructured substrate domain that contains many YxxP motifs, a serine-rich four-helix bundle, and a FAT-like C-terminal domain. Vertebrates contain four CAS proteins: BCAR1 (or p130Cas), NEDD9 (or HEF1), EFS (or SIN), and CASS4 (or HEPL). The SH3 domain of CAS proteins binds to diverse partners including FAK, FRNK, Pyk2, PTP-PEST, DOCK180, 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.

Pssm-ID: 212778 Cd Length: 56 Bit Score: 46.96 E-value: 7.34e-07

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|.
gi 63055065 229 IYPYTARDQDEMNLERGAVVEVVQKN---LEGWWKIRYQGKEGWAPASYLK 276
Cdd:cd11844   5 LYDNVAESPDELAFRRGDILTVLEQNtagLEGWWLCSLRGRQGIAPGNRLK 55

C-terminal (or second) Src homology 3 domain of VAV3 protein; VAV3 is ubiquitously expressed and functions as a phosphorylation-dependent guanine nucleotide exchange factor (GEF) for RhoA, RhoG, and Rac1. It has been implicated to function in the hematopoietic, bone, cerebellar, and cardiovascular systems. VAV3 is essential in axon guidance in neurons that control blood pressure and respiration. It is overexpressed in prostate cancer cells and it plays a role in regulating androgen receptor transcriptional activity. 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.

Pssm-ID: 212911 [Multi-domain] Cd Length: 56 Bit Score: 46.94 E-value: 7.40e-07

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|
gi 63055065 230 YPYTARDQDEMNLERGAVVEVVQKN-LEGWWKIRYQGKEGWAPASYLKKN 278
Cdd:cd11978   7 YDFCARDMRELSLLKGDVVKIYTKMsTNGWWRGEVNGRVGWFPSTYVEED 56

Second Src homology 3 domain (or SH3B) 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 second SH3 domain (or SH3B) of ITSN1 has been shown to bind WNK and CdGAP. 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.

Pssm-ID: 212771 [Multi-domain] Cd Length: 53 Bit Score: 46.59 E-value: 7.85e-07

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|...
gi 63055065 225 KYTVIYPYTARDQDEMNLERGAVVEVVQKnLEGWWKIRYQ-GKEGWAPASYLK 276
Cdd:cd11837   1 TATALYPWRAKKENHLSFAKGDIITVLEQ-QEMWWFGELEgGEEGWFPKSYVK 52

Second C-terminal Src homology 3 domain of Dynamin Binding Protein, also called Tuba, and similar domains; DNMBP or Tuba is a cdc42-specific guanine nucleotide exchange factor (GEF) that contains four N-terminal SH3 domains, a central RhoGEF [or Dbl homology (DH)] domain followed by a Bin/Amphiphysin/Rvs (BAR) domain, and two C-terminal SH3 domains. It provides a functional link between dynamin, Rho GTPase signaling, and actin dynamics. It plays an important role in regulating cell junction configuration. The C-terminal SH3 domains of DNMBP bind to N-WASP and Ena/VASP proteins, which are key regulatory proteins of the actin cytoskeleton. Also included in this subfamily is the second C-terminal SH3 domain of Rho guanine nucleotide exchange factor 37 (ARHGEF37), whose function is still unknown. 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.

Pssm-ID: 212734 [Multi-domain] Cd Length: 57 Bit Score: 46.98 E-value: 7.92e-07

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*
gi 63055065 156 QYVVVADYQKQESSEISLSVGQVVDIIE----KNESGWWFVSTAEEQGWVPATCL 206
Cdd:cd11800   1 YYYALYTFEARSPGELSVTEGQVVTVLEkhdlKGNPEWWLVEDRGKQGYVPSNYL 55

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.

Pssm-ID: 212760 [Multi-domain] Cd Length: 52 Bit Score: 46.55 E-value: 9.05e-07

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|
gi 63055065 225 KYTVIYPYTARDQDEMNLERGAVVEVVQKNLEGWWKIRYQGKEGWAPASY 274
Cdd:cd11826   1 KVVALYDYTADKDDELSFQEGDIIYVTKKNDDGWYEGVLNGVTGLFPGNY 50

Src Homology 3 domain of Tec-like Protein Tyrosine Kinases; The Tec (Tyrosine kinase expressed in hepatocellular carcinoma) subfamily is composed of Tec, Btk, Bmx (Etk), Itk (Tsk, Emt), Rlk (Txk), and similar proteins. They are cytoplasmic (or nonreceptor) tyr kinases containing Src homology protein interaction domains (SH3, SH2) N-terminal to the catalytic tyr kinase domain. Most Tec subfamily members (except Rlk) also contain an N-terminal pleckstrin homology (PH) domain, which binds the products of PI3K and allows membrane recruitment and activation. In addition, some members contain the Tec homology (TH) domain, which contains proline-rich and zinc-binding regions. Tec kinases are expressed mainly by haematopoietic cells, although Tec and Bmx are also found in endothelial cells. B-cells express Btk and Tec, while T-cells express Itk, Txk, and Tec. Collectively, Tec kinases are expressed in a variety of myeloid cells such as mast cells, platelets, macrophages, and dendritic cells. Each Tec kinase shows a distinct cell-type pattern of expression. The function of Tec kinases in lymphoid cells have been studied extensively. They play important roles in the development, differentiation, maturation, regulation, survival, and function of B-cells and T-cells. 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.

Pssm-ID: 212702 [Multi-domain] Cd Length: 54 Bit Score: 46.50 E-value: 9.84e-07

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*....
gi 63055065 230 YPYTARDQDEMNLERGAVVEVVQKNLEGWWKIR-YQGKEGWAPASYLKK 277
Cdd:cd11768   6 YDFQPIEPGDLPLEKGEEYVVLDDSNEHWWRARdKNGNEGYIPSNYVTE 54

Third Src homology 3 domain of Tyrosine kinase substrate with five SH3 domains; Tks5, also called SH3 and PX domain-containing protein 2A (SH3PXD2A) or Five SH (FISH), is a scaffolding protein and Src substrate that is localized in podosomes, which are electron-dense structures found in Src-transformed fibroblasts, osteoclasts, macrophages, and some invasive cancer cells. It binds and regulates some members of the ADAMs family of transmembrane metalloproteases, which function as sheddases and mediators of cell and matrix interactions. It is required for podosome formation, degradation of the extracellular matrix, and cancer cell invasion. Tks5 contains an N-terminal Phox homology (PX) domain and five SH3 domains. This model characterizes the third SH3 domain of Tks5. 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.

Pssm-ID: 213012 Cd Length: 54 Bit Score: 46.58 E-value: 1.00e-06

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*.
gi 63055065 852 YVAVANFEGD-EDTSSFQEGTVFEVREKNSSGWWFCQVlsgaPSWEGWIPSNYLRK 906
Cdd:cd12079   3 YYTIAEFQSCiSDGISFRGGQKAEVIEKNSGGWWYVQI----GEKEGWAPSSYIDK 54

Uncharacterized conserved protein YraI [Function unknown];

Pssm-ID: 444015 [Multi-domain] Cd Length: 92 Bit Score: 47.75 E-value: 1.05e-06

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*
gi 63055065 242 LERGAVVEVV-QKNLEGWWKIRYQGKEGWAPASYLKKNSGEPLPP 285
Cdd:COG4991  47 LPAGATVTVLgCTSGGGWCKVSYGGQRGWVSARYLQVSYDGQPVP 91

Fourth Src homology 3 domain (or SH3D) 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 fourth SH3 domain (or SH3D) of ITSN1 has been shown to bind SHIP2, Numb, CdGAP, and N-WASP. 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.

Pssm-ID: 212773 [Multi-domain] Cd Length: 58 Bit Score: 46.56 E-value: 1.05e-06

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....
gi 63055065 159 VVADYQKQESSEISLSVGQVVDIIEKNESGWWfvsTAEEQ--------GWVPAT 204
Cdd:cd11839   4 VIAPFTATAENQLSLAVGQLVLVRKKSPSGWW---EGELQargkkrqiGWFPAN 54

First Src Homology 3 domain of FCH and double SH3 domains proteins; This group is composed of FCH and double SH3 domains protein 1 (FCHSD1) and FCHSD2. These proteins have a common domain structure consisting of an N-terminal F-BAR (FES-CIP4 Homology and Bin/Amphiphysin/Rvs), two SH3, and C-terminal proline-rich domains. They have only been characterized in silico and their functions remain unknown. This group also includes the insect protein, nervous wreck, which acts as a regulator of synaptic growth signaling. 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.

Pssm-ID: 212695 [Multi-domain] Cd Length: 57 Bit Score: 46.59 E-value: 1.06e-06

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|...
gi 63055065 227 TVIYPYTARDQDEMNLERGAVVEVVQK-NLEGWWKIR-YQGKEGWAPASYLKK 277
Cdd:cd11761   5 KVLYSYEAQRPDELTITEGEELEVIEDgDGDGWVKARnKSGEVGYVPENYLQF 57

Second or C-terminal Src homology 3 domain of the p47phox subunit of NADPH oxidase, also called Neutrophil Cytosolic Factor 1; p47phox, or NCF1, is a cytosolic subunit of the phagocytic NADPH oxidase complex (also called Nox2 or gp91phox), which plays a key role in the ability of phagocytes to defend against bacterial infections. NADPH oxidase catalyzes the transfer of electrons from NADPH to oxygen during phagocytosis forming superoxide and reactive oxygen species. p47phox is required for activation of NADH oxidase and plays a role in translocation. It contains an N-terminal Phox homology (PX) domain, tandem SH3 domains (N-SH3 and C-SH3), a polybasic/autoinhibitory region, and a C-terminal proline-rich region (PRR). This model characterizes the second SH3 domain (or C-SH3) of p47phox. In its inactive state, the tandem SH3 domains interact intramolecularly with the autoinhibitory region; upon activation, the tandem SH3 domains are exposed through a conformational change, resulting in their binding to the PRR of p22phox and the activation of NADPH oxidase. 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.

Pssm-ID: 212955 [Multi-domain] Cd Length: 53 Bit Score: 46.37 E-value: 1.15e-06

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|.
gi 63055065 157 YVVVADYQKQESSEISLSVGQVVDIIEKNESGWWFVSTAEEQGWVPATCLE 207
Cdd:cd12022   2 YITIKAYTAVEEDELTLLEGEAIEVIHKLLDGWWVVRKGEVTGYFPSMYLQ 52

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.

Pssm-ID: 212759 [Multi-domain] Cd Length: 54 Bit Score: 46.17 E-value: 1.20e-06

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|
gi 63055065 229 IYPYTARDQDEMNLERGAVVEVVQKNLEGWWKIRYQGK-EGWAPASYLKK 277
Cdd:cd11825   5 LYDYRAQRPDELSFCKHAIITNVEKEDGGWWRGDYGGKkQKWFPANYVEE 54

Src Homology 3 domain of Abelson helper integration site-1 (AHI-1); AHI-1, also called Jouberin, is expressed in high levels in the brain, gonad tissues, and skeletal muscle. It is an adaptor protein that interacts with the small GTPase Rab8a and regulates it distribution and function, affecting cilium formation and vesicle transport. Mutations in the AHI-1 gene can cause Joubert syndrome, a disorder characterized by brainstem malformations, cerebellar aplasia/hypoplasia, and retinal dystrophy. AHI-1 variation is also associated with susceptibility to schizophrenia and type 2 diabetes mellitus progression. AHI-1 contains WD40 and SH3 domains. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

Pssm-ID: 212746 [Multi-domain] Cd Length: 52 Bit Score: 46.35 E-value: 1.20e-06

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*...
gi 63055065 229 IYPYTARDQDEMNLERGAVVEVVQKNLEGWWKIRY-QGKEGWAPASYL 275
Cdd:cd11812   5 LYDYTANRSDELTIHRGDIIRVLYKDNDNWWFGSLvNGQQGYFPANYV 52

First 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 first 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.

Pssm-ID: 212845 [Multi-domain] Cd Length: 55 Bit Score: 46.06 E-value: 1.28e-06

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|.
gi 63055065 228 VIYPYTARDQDEMNLERGAVVEVVQKN-LEGWWKIRY-QGKEGWAPASYLK 276
Cdd:cd11912   4 VLYDYTASGDDEVSISEGEEVTVLEPDdGSGWTKVRNgSGEEGLVPTSYIE 54

The phosphoinositide binding Phox Homology Domain of the Beta Isoform of Class II Phosphoinositide 3-Kinases; The PX domain is a phosphoinositide (PI) binding module present in many proteins with diverse functions. The Phosphoinositide 3-Kinase (PI3K) family of enzymes catalyzes the phosphorylation of the 3-hydroxyl group of the inositol ring of phosphatidylinositol. PI3Ks play an important role in a variety of fundamental cellular processes, including cell motility, the Ras pathway, vesicle trafficking and secretion, immune cell activation and apoptosis. PI3Ks are divided into three main classes (I, II, and III) based on their substrate specificity, regulation, and domain structure. Class II PI3Ks preferentially use PI as a substrate to produce PI3P, but can also phosphorylate PI4P to produce PI(3,4)P2. They function as monomers and do not associate with any regulatory subunits. Class II enzymes contain an N-terminal Ras binding domain, a lipid binding C2 domain, a PI3K homology domain of unknown function, an ATP-binding cataytic domain, a PX domain, and a second C2 domain at the C-terminus. The class II beta isoform, PI3K-C2beta, contributes to the migration and survival of cancer cells. It regulates Rac activity and impacts membrane ruffling, cell motility, and cadherin-mediated cell-cell adhesion. The PX domain is involved in targeting of proteins to PI-enriched membranes, and may also be involved in protein-protein interaction.

Pssm-ID: 132823 Cd Length: 109 Bit Score: 48.00 E-value: 1.31e-06

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 63055065  21 PNKHYVYIIRVTwSSGATEAIY--RRYSKFFDLQMQMLDKFPmeggqkdpkQRIIPFLPGKILFRRSHIRDVAVKRLIPI 98
Cdd:cd07290  13 PSKGYAYVVKVQ-REGHKEATFvqRTFEEFQELHNKLRLLFP---------SSKLPSFPSRFVIGRSRGEAVAERRKEEL 82

                        90       100
                ....*....|....*....|....
gi 63055065  99 DEYCKALIQLPPYISQCDEVLQFF 122
Cdd:cd07290  83 NGYIWHLIHAPPEVAECDLVYTFF 106

Src Homology 3 domain of Mixed Lineage Kinases; MLKs are Serine/Threonine Kinases (STKs), 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. Mammals have four MLKs (MLK1-4), mostly conserved in vertebrates, which contain 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.

Pssm-ID: 212809 [Multi-domain] Cd Length: 58 Bit Score: 45.97 E-value: 1.42e-06

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*
gi 63055065 226 YTVIYPYTARDQDEMNLERGAVVEVVQKNL-----EGWWKIRYQGKEGWAPASYL 275
Cdd:cd11876   2 WTALFDYDARGEDELTLRRGQPVEVLSKDAavsgdEGWWTGKIGDKVGIFPSNYV 56

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.

Pssm-ID: 212779 [Multi-domain] Cd Length: 52 Bit Score: 46.04 E-value: 1.43e-06

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*.
gi 63055065 851 LYVAVANFEG--DEDTSsFQEGTVFEVREKNSSGWWFCQVLS-GApswEGWIPSNY 903
Cdd:cd11845   1 IYVALYDYEArtDDDLS-FKKGDRLQILDDSDGDWWLARHLStGK---EGYIPSNY 52

Second Src Homology 3 domain (SH3B) 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 second SH3 domain (SH3B) of CD2AP. SH3B binds to c-Cbl in a site (TPSSRPLR is the core binding motif) distinct from the c-Cbl/SH3A 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.

Pssm-ID: 212987 [Multi-domain] Cd Length: 55 Bit Score: 46.11 E-value: 1.46e-06

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|
gi 63055065 228 VIYPYTARDQDEMNLERGAVVEVVQKNLEGWWKIRYQGKEGWAPASYLKK 277
Cdd:cd12054   5 VLFEYVPQNEDELELKVGDIIDINEEVEEGWWSGTLNGKSGLFPSNFVKE 54

Second Src homology 3 domain of Tyrosine kinase substrate (Tks) proteins; Tks proteins are Src substrates and scaffolding proteins that play important roles in the formation of podosomes and invadopodia, the dynamic actin-rich structures that are related to cell migration and cancer cell invasion. Vertebrates contain two Tks proteins, Tks4 (Tyr kinase substrate with four SH3 domains) and Tks5 (Tyr kinase substrate with five SH3 domains), which display partially overlapping but non-redundant functions. Both associate with the ADAMs family of transmembrane metalloproteases, which function as sheddases and mediators of cell and matrix interactions. Tks5 interacts with N-WASP and Nck, while Tks4 is essential for the localization of MT1-MMP (membrane-type 1 matrix metalloproteinase) to invadopodia. Tks proteins contain an N-terminal Phox homology (PX) domain and four or five SH3 domains. This model characterizes the second SH3 domain of Tks 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.

Pssm-ID: 212949 Cd Length: 54 Bit Score: 45.91 E-value: 1.50e-06

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*.
gi 63055065 852 YVAVANFEG-DEDTSSFQEGTVFEVREKNSSGWWFCQVLSGapswEGWIPSNYLRK 906
Cdd:cd12016   3 YITTQAYKAeNEDEIGFETGVVVEVIQKNLDGWWKIRYQGK----EGWAPATYLKK 54

Src homology 3 domain of SH3 and multiple ankyrin repeat domains (Shank) proteins; Shank proteins carry scaffolding functions through multiple sites of protein-protein interaction in its domain architecture, including ankyrin (ANK) repeats, a long proline rich region, as well as SH3, PDZ, and SAM domains. They bind a variety of membrane and cytosolic proteins, and exist in alternatively spliced isoforms. They are highly enriched in postsynaptic density (PSD) where they interact with the cytoskeleton and with postsynaptic membrane receptors including NMDA and glutamate receptors. They are crucial in the construction and organization of the PSD and dendritic spines of excitatory synapses. There are three members of this family (Shank1, Shank2, Shank3) which show distinct and cell-type specific patterns of expression. Shank1 is brain-specific; Shank2 is found in neurons, glia, endocrine cells, liver, and kidney; Shank3 is widely expressed. The SH3 domain of Shank binds GRIP, a scaffold protein that binds AMPA receptors and Eph receptors/ligands. 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.

Pssm-ID: 212766 Cd Length: 50 Bit Score: 45.89 E-value: 1.57e-06

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|
gi 63055065 156 QYVVVADYQKQESSEISLSVGQVVDIIEKNESGWWFVSTAEEQGWVPATC 205
Cdd:cd11832   1 YFIAVKSYSPQEEGEISLHKGDRVKVLSIGEGGFWEGSVRGRTGWFPSDC 50

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.

Pssm-ID: 212764 [Multi-domain] Cd Length: 54 Bit Score: 45.70 E-value: 1.69e-06

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*....
gi 63055065 230 YPYTARDQDEMNLERGAVVEVVQK-NLEGWWKIRYQGKEGWAPASYLKK 277
Cdd:cd11830   6 YDFCARDMRELSLKEGDVVKIYNKkGQQGWWRGEINGRIGWFPSTYVEE 54

Variant SH3 domain;

Pssm-ID: 434066 [Multi-domain] Cd Length: 49 Bit Score: 45.30 E-value: 2.18e-06

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*....
gi 63055065   159 VVADYQKQESSEISLSVGQVVDIIEKNESGWWFVSTAEEQGWVPATCLE 207
Cdd:pfam14604   1 ALYPYEPKDDDELSLQRGDVITVIEESEDGWWEGINTGRTGLVPANYVE 49

Second C-terminal Src homology 3 domain of Dynamin Binding Protein, also called Tuba, and similar domains; DNMBP or Tuba is a cdc42-specific guanine nucleotide exchange factor (GEF) that contains four N-terminal SH3 domains, a central RhoGEF [or Dbl homology (DH)] domain followed by a Bin/Amphiphysin/Rvs (BAR) domain, and two C-terminal SH3 domains. It provides a functional link between dynamin, Rho GTPase signaling, and actin dynamics. It plays an important role in regulating cell junction configuration. The C-terminal SH3 domains of DNMBP bind to N-WASP and Ena/VASP proteins, which are key regulatory proteins of the actin cytoskeleton. Also included in this subfamily is the second C-terminal SH3 domain of Rho guanine nucleotide exchange factor 37 (ARHGEF37), whose function is still unknown. 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.

Pssm-ID: 212734 [Multi-domain] Cd Length: 57 Bit Score: 45.44 E-value: 2.26e-06

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*.
gi 63055065 226 YTVIYPYTARDQDEMNLERGAVVEVVQK-NLEG---WWKIRYQGKEGWAPASYLKK 277
Cdd:cd11800   2 YYALYTFEARSPGELSVTEGQVVTVLEKhDLKGnpeWWLVEDRGKQGYVPSNYLAK 57

Third Src homology 3 domain of Tyrosine kinase substrate with four SH3 domains; Tks4, also called SH3 and PX domain-containing protein 2B (SH3PXD2B) or HOFI, is a Src substrate and scaffolding protein that plays an important role in the formation of podosomes and invadopodia, the dynamic actin-rich structures that are related to cell migration and cancer cell invasion. It is required in the formation of functional podosomes, EGF-induced membrane ruffling, and lamellipodia generation. It plays an important role in cellular attachment and cell spreading. Tks4 is essential for the localization of MT1-MMP (membrane-type 1 matrix metalloproteinase) to invadopodia. It contains an N-terminal Phox homology (PX) domain and four SH3 domains. This model characterizes the third SH3 domain of Tks4. 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.

Pssm-ID: 213011 Cd Length: 53 Bit Score: 45.45 E-value: 2.46e-06

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*.
gi 63055065 852 YVAVANFEGD-EDTSSFQEGTVFEVREKNSSGWWFCQVlsgaPSWEGWIPSNYLRK 906
Cdd:cd12078   2 YYTIADFQTTiPDGISFQAGLKVEVIEKNLSGWWYIQI----EDKEGWAPATFIDK 53

Second Src homology 3 domain of Tyrosine kinase substrate with five SH3 domains; Tks5, also called SH3 and PX domain-containing protein 2A (SH3PXD2A) or Five SH (FISH), is a scaffolding protein and Src substrate that is localized in podosomes, which are electron-dense structures found in Src-transformed fibroblasts, osteoclasts, macrophages, and some invasive cancer cells. It binds and regulates some members of the ADAMs family of transmembrane metalloproteases, which function as sheddases and mediators of cell and matrix interactions. It is required for podosome formation, degradation of the extracellular matrix, and cancer cell invasion. Tks5 contains an N-terminal Phox homology (PX) domain and five SH3 domains. This model characterizes the second SH3 domain of Tks5. 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.

Pssm-ID: 213010 Cd Length: 54 Bit Score: 45.41 E-value: 2.50e-06

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*.
gi 63055065 852 YVAVANFEGD-EDTSSFQEGTVFEVREKNSSGWWFCQVLSGapswEGWIPSNYLRK 906
Cdd:cd12077   3 YVTVQPYTSQgKDEIGFEKGVTVEVIQKNLEGWWYIRYLGK----EGWAPASYLKK 54

Fifth (C-terminal) Src homology 3 domain of Tyrosine kinase substrate with five SH3 domains; Tks5, also called SH3 and PX domain-containing protein 2A (SH3PXD2A) or Five SH (FISH), is a scaffolding protein and Src substrate that is localized in podosomes, which are electron-dense structures found in Src-transformed fibroblasts, osteoclasts, macrophages, and some invasive cancer cells. It binds and regulates some members of the ADAMs family of transmembrane metalloproteases, which function as sheddases and mediators of cell and matrix interactions. It is required for podosome formation, degradation of the extracellular matrix, and cancer cell invasion. Tks5 contains an N-terminal Phox homology (PX) domain and five SH3 domains. This model characterizes the fifth (C-terminal) SH3 domain of Tks5. 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.

Pssm-ID: 212953 Cd Length: 57 Bit Score: 45.34 E-value: 2.67e-06

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*
gi 63055065 157 YVVVADYQKQESSeISLSVGQVVDIIEKNESGWWFVSTAE----EQGWVPATCLE 207
Cdd:cd12020   2 YVSIADYEGDEET-AGFQEGVSMEVLEKNPNGWWYCQILDgvkpFKGWVPSNYLE 55

Src Homology 3 domain of Nephrocystin (or Nephrocystin-1); Nephrocystin contains an SH3 domain involved in signaling pathways that regulate cell adhesion and cytoskeletal organization. It is a protein that in humans is associated with juvenile nephronophthisis, an inherited kidney disease characterized by renal fibrosis that lead to chronic renal failure in children. It is localized in cell-cell junctions in renal duct cells, and is known to interact with Ack1, an activated Cdc42-associated kinase. 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.

Pssm-ID: 212704 [Multi-domain] Cd Length: 54 Bit Score: 45.00 E-value: 2.79e-06

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*..
gi 63055065 851 LYVAVANFEGDEDTS-SFQEGTVFEVREKNSSGWWFCQVLSGApswEGWIPSNYLRK 906
Cdd:cd11770   1 LYEALSDFQAEQEGDlSFKKGEVLRIISKRADGWWLAENSKGN---RGLVPKTYLKV 54

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.

Pssm-ID: 212806 [Multi-domain] Cd Length: 53 Bit Score: 44.95 E-value: 2.92e-06

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|
gi 63055065 228 VIYPYTARDQDEMNLERGAVVEVVQKNLEGWWKIRYQGKEGWAPASYLKK 277
Cdd:cd11873   4 VEFDYDAEEPDELTLKVGDIITNVKKMEEGWWEGTLNGKRGMFPDNFVKV 53

Uncharacterized conserved protein YgiM, contains N-terminal SH3 domain, DUF1202 family [General function prediction only];

Pssm-ID: 442337 [Multi-domain] Cd Length: 119 Bit Score: 47.04 E-value: 3.02e-06

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*.
gi 63055065 242 LERGAVVEVVQKNlEGWWKIRY-QGKEGWAPASYLKKNSGEPLPPK 286
Cdd:COG3103  30 LPKGEKVTVLGRS-GGWYKVRYsNGKTGWVSSRYLTVTPSARERLP 74

Src homology 3 domain of Alpha Spectrin; Spectrin is a major structural component of the red blood cell membrane skeleton and is important in erythropoiesis and membrane biogenesis. It is a flexible, rope-like molecule composed of two subunits, alpha and beta, which consist of many spectrin-type repeats. Alpha and beta spectrin associate to form heterodimers and tetramers; spectrin tetramer formation is critical for red cell shape and deformability. Defects in alpha spectrin have been associated with inherited hemolytic anemias including hereditary spherocytosis (HSp), hereditary elliptocytosis (HE), and hereditary pyropoikilocytosis (HPP). Alpha spectrin contains a middle SH3 domain and a C-terminal EF-hand binding motif in addition to multiple spectrin repeats. 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.

Pssm-ID: 212742 [Multi-domain] Cd Length: 53 Bit Score: 44.78 E-value: 3.76e-06

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|
gi 63055065 158 VVVADYQKQESSEISLSVGQVVDIIEKNESGWWFVSTAEEQGWVPATCLE 207
Cdd:cd11808   3 VALYDYQEKSPREVSMKKGDILTLLNSSNKDWWKVEVNDRQGFVPAAYVK 52

First or N-terminal Src homology 3 domain of the p47phox subunit of NADPH oxidase, also called Neutrophil Cytosolic Factor 1; p47phox, or NCF1, is a cytosolic subunit of the phagocytic NADPH oxidase complex (also called Nox2 or gp91phox), which plays a key role in the ability of phagocytes to defend against bacterial infections. NADPH oxidase catalyzes the transfer of electrons from NADPH to oxygen during phagocytosis forming superoxide and reactive oxygen species. p47phox is required for activation of NADH oxidase and plays a role in translocation. It contains an N-terminal Phox homology (PX) domain, tandem SH3 domains (N-SH3 and C-SH3), a polybasic/autoinhibitory region, and a C-terminal proline-rich region (PRR). This model characterizes the first SH3 domain (or N-SH3) of p47phox. In its inactive state, the tandem SH3 domains interact intramolecularly with the autoinhibitory region; upon activation, the tandem SH3 domains are exposed through a conformational change, resulting in their binding to the PRR of p22phox and the activation of NADPH oxidase. 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.

Pssm-ID: 212954 [Multi-domain] Cd Length: 53 Bit Score: 44.95 E-value: 3.88e-06

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....
gi 63055065 852 YVAVANFEGDEDTS-SFQEGTVFEVREKNSSGWWFCQVlsgaPSWEGWIPSNYL 904
Cdd:cd12021   2 YRAIADYEKSSKSEmALKTGDVVEVVEKSENGWWFCQL----KAKRGWVPASYL 51

Second or C-terminal Src homology 3 domain of NADPH oxidase (Nox) Organizing protein 1; Nox Organizing protein 1 (NoxO1) is a critical regulator of enzyme kinetics of the nonphagocytic NADPH oxidase Nox1, which catalyzes the transfer of electrons from NADPH to molecular oxygen to form superoxide. Nox1 is expressed in colon, stomach, uterus, prostate, and vascular smooth muscle cells. NoxO1 is involved in targeting activator subunits (such as NoxA1) to Nox1. It is co-localized with Nox1 in the membranes of resting cells and directs the subcellular localization of Nox1. NoxO1 contains an N-terminal Phox homology (PX) domain, tandem SH3 domains (N-SH3 and C-SH3), and a C-terminal proline-rich region (PRR). This model characterizes the second SH3 domain (or C-SH3) of NoxO1. The tandem SH3 domains of NoxO1 interact with the PRR of p22phox, which also complexes with Nox1. 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.

Pssm-ID: 212957 Cd Length: 53 Bit Score: 44.64 E-value: 4.08e-06

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|
gi 63055065 373 YYTIAEFQTTIPDGISFQAGLKVEVIEKSLSGWWYIQMEDKEGWAPATFI 422
Cdd:cd12024   2 YYATRAYEAQKEDELSVPAGVVVEVLQKSDNGWWLIRYNGRAGYVPSMYL 51

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.

Pssm-ID: 212690 [Multi-domain] Cd Length: 51 Bit Score: 44.38 E-value: 4.51e-06

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|
gi 63055065 373 YYTIAEFQTTIPDGISFQAGLKVEVIEKSLSGWWYIQMED-KEGWAPATF 421
Cdd:cd00174   2 ARALYDYEAQDDDELSFKKGDIITVLEKDDDGWWEGELNGgREGLFPANY 51

Fifth Src homology 3 domain (or SH3E) of Intersectin-2; Intersectin-2 (ITSN2) is an adaptor protein that functions in exo- and endocytosis, actin cytoskeletal reorganization, and signal transduction. It plays a role in clathrin-coated pit (CCP) formation. It binds to many proteins through its multidomain structure and facilitate the assembly of multimeric complexes. ITSN2 also functions as a specific GEF for Cdc42 activation in epithelial morphogenesis, and is required in mitotic spindle orientation. It exists in alternatively spliced short and long isoforms. The short isoform contains two Eps15 homology domains (EH1 and EH2), a coiled-coil region and five SH3 domains (SH3A-E), while the long isoform, in addition, contains RhoGEF (also called Dbl-homologous or DH), Pleckstrin homology (PH) and C2 domains. The fifth SH3 domain (or SH3E) of ITSN2 is expected to bind protein partners, similar to ITSN1 which 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.

Pssm-ID: 212929 [Multi-domain] Cd Length: 54 Bit Score: 44.59 E-value: 4.58e-06

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*...
gi 63055065 229 IYPYTARDQDEMNLERGAVVEVVQKNLEGWWKIRYQGKEGWAPASYLK 276
Cdd:cd11996   6 MYDYTANNEDELSFSKGQLINVLNKDDPDWWQGEINGVTGLFPSNYVK 53

First Src homology 3 domain (or SH3A) of Intersectin-1; Intersectin-1 (ITSN1) is an adaptor protein that functions in exo- and endocytosis, actin cytoskeletal reorganization, and signal transduction. It plays a role in clathrin-coated pit (CCP) formation. It binds to many proteins through its multidomain structure and facilitate the assembly of multimeric complexes. ITSN1 localizes in membranous organelles, CCPs, the Golgi complex, and may be involved in the cell membrane trafficking system. It exists in alternatively spliced short and long isoforms. The short isoform contains two Eps15 homology domains (EH1 and EH2), a coiled-coil region and five SH3 domains (SH3A-E), while the long isoform, in addition, contains RhoGEF (also called Dbl-homologous or DH), Pleckstrin homology (PH) and C2 domains. The first SH3 domain (or SH3A) of ITSN1 has been shown to bind many proteins including Sos1, dynamin1/2, CIN85, c-Cbl, PI3K-C2, SHIP2, N-WASP, and CdGAP, among others. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

Pssm-ID: 212920 [Multi-domain] Cd Length: 55 Bit Score: 44.60 E-value: 4.60e-06

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....
gi 63055065 226 YTVIYPYTARDQDEMNLERGAVVEV--VQKNLEGWWKIRYQGKEGWAPASYLKK 277
Cdd:cd11987   2 YRALYPFEARSHDEITIQPGDIVMVdeSQTGEPGWLGGELKGKTGWFPANYAEK 55

Src homology 3 domain of ARHGEF9-like Rho guanine nucleotide exchange factors; Members of this family contain a SH3 domain followed by RhoGEF (also called Dbl-homologous or DH) and Pleckstrin Homology (PH) domains. They include the Rho guanine nucleotide exchange factors ARHGEF9, ASEF (also called ARHGEF4), ASEF2, and similar proteins. GEFs activate small GTPases by exchanging bound GDP for free GTP. ARHGEF9 specifically activates Cdc42, while both ASEF and ASEF2 can activate Rac1 and Cdc42. ARHGEF9 is highly expressed in the brain and it interacts with gephyrin, a postsynaptic protein associated with GABA and glycine receptors. ASEF plays a role in angiogenesis and cell migration. ASEF2 is important in cell migration and adhesion dynamics. ASEF exists in an autoinhibited form and is activated upon binding of the tumor suppressor APC (adenomatous polyposis coli), leading to the activation of Rac1 or Cdc42. In its autoinhibited form, the SH3 domain of ASEF forms an extensive interface with the DH and PH domains, blocking the Rac 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.

Pssm-ID: 212762 [Multi-domain] Cd Length: 53 Bit Score: 44.29 E-value: 4.96e-06

                        10        20        30        40
                ....*....|....*....|....*....|....*....|...
gi 63055065 162 DYQKQESSEISLSVGQVVDIIEKNESGWWFVSTAEEQGWVPAT 204
Cdd:cd11828   7 DHVTMDPEELGFKAGDVIEVLDMSDKDWWWGSIRDEEGWFPAS 49

Fifth (C-terminal) Src homology 3 domain of Tyrosine kinase substrate with five SH3 domains; Tks5, also called SH3 and PX domain-containing protein 2A (SH3PXD2A) or Five SH (FISH), is a scaffolding protein and Src substrate that is localized in podosomes, which are electron-dense structures found in Src-transformed fibroblasts, osteoclasts, macrophages, and some invasive cancer cells. It binds and regulates some members of the ADAMs family of transmembrane metalloproteases, which function as sheddases and mediators of cell and matrix interactions. It is required for podosome formation, degradation of the extracellular matrix, and cancer cell invasion. Tks5 contains an N-terminal Phox homology (PX) domain and five SH3 domains. This model characterizes the fifth (C-terminal) SH3 domain of Tks5. 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.

Pssm-ID: 212953 Cd Length: 57 Bit Score: 44.57 E-value: 4.96e-06

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*.
gi 63055065 226 YTVIYPYTArDQDEMNLERGAVVEVVQKNLEGWWKIRY----QGKEGWAPASYLKK 277
Cdd:cd12020   2 YVSIADYEG-DEETAGFQEGVSMEVLEKNPNGWWYCQIldgvKPFKGWVPSNYLEK 56

Src homology 3 domain of Alpha Spectrin; Spectrin is a major structural component of the red blood cell membrane skeleton and is important in erythropoiesis and membrane biogenesis. It is a flexible, rope-like molecule composed of two subunits, alpha and beta, which consist of many spectrin-type repeats. Alpha and beta spectrin associate to form heterodimers and tetramers; spectrin tetramer formation is critical for red cell shape and deformability. Defects in alpha spectrin have been associated with inherited hemolytic anemias including hereditary spherocytosis (HSp), hereditary elliptocytosis (HE), and hereditary pyropoikilocytosis (HPP). Alpha spectrin contains a middle SH3 domain and a C-terminal EF-hand binding motif in addition to multiple spectrin repeats. 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.

Pssm-ID: 212742 [Multi-domain] Cd Length: 53 Bit Score: 44.40 E-value: 5.04e-06

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|
gi 63055065 228 VIYPYTARDQDEMNLERGAVVEVVQKNLEGWWKIRYQGKEGWAPASYLKK 277
Cdd:cd11808   4 ALYDYQEKSPREVSMKKGDILTLLNSSNKDWWKVEVNDRQGFVPAAYVKK 53

Second Src Homology 3 domain (SH3B) of Cbl-interacting protein of 85 kDa; CIN85, also called SH3 domain-containing kinase-binding protein 1 (SH3KBP1) or CD2-binding protein 3 (CD2BP3) or Ruk, is an adaptor protein that is involved in the downregulation of receptor tyrosine kinases by facilitating endocytosis through interaction with endophilin-associated ubiquitin ligase Cbl proteins. It is also important in many other cellular processes including vesicle-mediated transport, cytoskeletal remodelling, apoptosis, cell adhesion and migration, and viral infection, among others. CIN85 exists as multiple variants from alternative splicing; the main variant contains three SH3 domains, a proline-rich region, and a C-terminal coiled-coil domain. All of these domains enable CIN85 to bind various protein partners and assemble complexes that have been implicated in many different functions. This alignment model represents the second SH3 domain (SH3B) of CIN85. SH3B has been shown to bind Cbl proline-rich peptides and 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.

Pssm-ID: 212988 [Multi-domain] Cd Length: 53 Bit Score: 44.60 E-value: 5.07e-06

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|
gi 63055065 228 VIYPYTARDQDEMNLERGAVVEVVQKNLEGWWKIRYQGKEGWAPASYLKK 277
Cdd:cd12055   4 VAFSYLPQNEDELELKVGDIIEVVGEVEEGWWEGVLNGKTGMFPSNFIKE 53

Src homology 3 domain of APC-Stimulated guanine nucleotide Exchange Factor 2; ASEF2, also called Spermatogenesis-associated protein 13 (SPATA13), is a GEF that localizes with actin at the leading edge of cells and is important in cell migration and adhesion dynamics. GEFs activate small GTPases by exchanging bound GDP for free GTP. ASEF2 can activate both Rac 1 and Cdc42, but only Rac1 activation is necessary for increased cell migration and adhesion turnover. Together with APC (adenomatous polyposis coli) and Neurabin2, a scaffold protein that binds F-actin, it is involved in regulating HGF-induced cell migration. ASEF2 contains a SH3 domain followed by RhoGEF (also called Dbl-homologous or DH) and Pleckstrin Homology (PH) domains. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

Pssm-ID: 212907 Cd Length: 54 Bit Score: 44.28 E-value: 5.16e-06

                        10        20        30
                ....*....|....*....|....*....|....*.
gi 63055065 387 ISFQAGLKVEVIEKSLSGWWYIQMEDKEGWAPATFI 422
Cdd:cd11974  17 LAFKAGDVIRVLEASNKDWWWGRNEDREAWFPASFV 52

Src homology 3 domain of Type I fungal Myosins; Type I myosins (myosin-I) are actin-dependent motors in endocytic actin structures and actin patches. They play roles in membrane traffic in endocytic and secretory pathways, cell motility, and mechanosensing. Saccharomyces cerevisiae has two myosins-I, Myo3 and Myo5, which are involved in endocytosis and the polarization of the actin cytoskeleton. Myosin-I contains an N-terminal actin-activated ATPase, a phospholipid-binding TH1 (tail homology 1) domain, and a C-terminal extension which includes an F-actin-binding TH2 domain, an SH3 domain, and an acidic peptide that participates in activating the Arp2/3complex. The SH3 domain of myosin-I is required for myosin-I-induced actin polymerization. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

Pssm-ID: 212792 [Multi-domain] Cd Length: 55 Bit Score: 44.30 E-value: 5.91e-06

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....
gi 63055065 852 YVAVANFEGDEDTS-SFQEGTVFEVREKNSSGWWFCQVLSGapSWEGWIPSNYL 904
Cdd:cd11858   2 YKALYDFAGSVANElSLKKDDIVYIVQKEDNGWWLAKKLDE--SKEGWVPAAYL 53

Third Src Homology 3 domain (SH3C) of Cbl-interacting protein of 85 kDa; CIN85, also called SH3 domain-containing kinase-binding protein 1 (SH3KBP1) or CD2-binding protein 3 (CD2BP3) or Ruk, is an adaptor protein that is involved in the downregulation of receptor tyrosine kinases by facilitating endocytosis through interaction with endophilin-associated ubiquitin ligase Cbl proteins. It is also important in many other cellular processes including vesicle-mediated transport, cytoskeletal remodelling, apoptosis, cell adhesion and migration, and viral infection, among others. CIN85 exists as multiple variants from alternative splicing; the main variant contains three SH3 domains, a proline-rich region, and a C-terminal coiled-coil domain. All of these domains enable CIN85 to bind various protein partners and assemble complexes that have been implicated in many different functions. This alignment model represents the third SH3 domain (SH3C) of CIN85. SH3C has been shown to bind ubiquitin. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

Pssm-ID: 212990 [Multi-domain] Cd Length: 56 Bit Score: 44.50 E-value: 6.03e-06

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|.
gi 63055065 228 VIYPYTARDQDEMNLERGAVVEVVQKNL--EGWWKIRYQGKEGWAPASYLK 276
Cdd:cd12057   4 VLFPYEAQNEDELTIKEGDIVTLISKDCidAGWWEGELNGRRGVFPDNFVK 54

Third Src Homology 3 domain of Nck1 adaptor protein; Nck1 (also called Nckalpha) plays a crucial role in connecting signaling pathways of tyrosine kinase receptors and important effectors in actin dynamics and cytoskeletal remodeling. It binds and activates RasGAP, resulting in the downregulation of Ras. It is also involved in the signaling of endothilin-mediated inhibition of cell migration. Nck adaptor proteins regulate actin cytoskeleton dynamics by linking proline-rich effector molecules to protein tyrosine kinases and phosphorylated signaling intermediates. They contain three SH3 domains and a C-terminal SH2 domain. They function downstream of the PDGFbeta receptor and are involved in Rho GTPase signaling and actin dynamics. Vertebrates contain two Nck adaptor proteins: Nck1 (also called Nckalpha) and Nck2, which show partly overlapping functions but also bind distinct targets. The third SH3 domain of Nck appears to prefer ligands with a PxAPxR motif. SH3 domains are protein interaction domains that usually bind to proline-rich ligands with moderate affinity and selectivity, preferentially a PxxP motif. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

Pssm-ID: 212837 [Multi-domain] Cd Length: 57 Bit Score: 44.25 E-value: 6.30e-06

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|
gi 63055065 229 IYPYTARDQDEMNLERGAVVEVVQK--NLEGWWKIR-YQGKEGWAPASYL 275
Cdd:cd11904   6 LYPFSSSNDEELNFEKGEVMDVIEKpeNDPEWWKCRkANGQVGLVPKNYV 55

Src Homology 3 domain of beta-Pak Interactive eXchange factor; Beta-PIX, also called Rho guanine nucleotide exchange factor 7 (ARHGEF7) or Cool (Cloned out of Library)-1, activates small GTPases by exchanging bound GDP for free GTP. It acts as a GEF for both Cdc42 and Rac 1, and plays important 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.

Pssm-ID: 212994 [Multi-domain] Cd Length: 54 Bit Score: 43.91 E-value: 7.39e-06

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*...
gi 63055065 230 YPYTARDQDEMNLERGAVVEVVQKNLEGWWKIRYQGKEGWAPASYLKK 277
Cdd:cd12061   6 FNFQQTNEDELSFSKGDVIHVTRVEEGGWWEGTHNGRTGWFPSNYVRE 53

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

Pssm-ID: 212700 [Multi-domain] Cd Length: 53 Bit Score: 43.79 E-value: 7.73e-06

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*..
gi 63055065 156 QYVVVADYQKQESSEISLSVGQVVDIIEKNESGWWFVSTAEEQGWVP 202
Cdd:cd11766   1 PAVVKFNYEAQREDELSLRKGDRVLVLEKSSDGWWRGECNGQVGWFP 47

Src homology 3 domain of SH3 and multiple ankyrin repeat domains protein 1; Shank1, also called SSTRIP (Somatostatin receptor-interacting protein), is a brain-specific protein that plays a role in the construction of postsynaptic density (PSD) and the maturation of dendritic spines. Mice deficient in Shank1 show altered PSD composition, thinner PSDs, smaller dendritic spines, and weaker basal synaptic transmission, although synaptic plasticity is normal. They show increased anxiety and impaired fear memory, but also show better spatial learning. Shank proteins carry scaffolding functions through multiple sites of protein-protein interaction in its domain architecture, including ankyrin (ANK) repeats, a long proline rich region, as well as SH3, PDZ, and SAM domains. The SH3 domain of Shank binds GRIP, a scaffold protein that binds AMPA receptors and Eph receptors/ligands. 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.

Pssm-ID: 212915 [Multi-domain] Cd Length: 52 Bit Score: 43.85 E-value: 8.48e-06

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|
gi 63055065 157 YVVVADYQKQESSEISLSVGQVVDIIEKNESGWWFVSTAEEQGWVPATCL 206
Cdd:cd11982   3 FMAVKPYQSQAEGEISLSKGEKIKVLSVGEGGFWEGQVKGRVGWFPSDCV 52

Src homology 3 domain of Rho GTPase-activating proteins 32 and 33, and similar proteins; Members of this family contain N-terminal PX and Src Homology 3 (SH3) domains, a central Rho GAP domain, and C-terminal extensions. RhoGAPs (or ARHGAPs) bind to Rho proteins and enhance the hydrolysis rates of bound GTP. ARHGAP32 is also called RICS, PX-RICS, p250GAP, or p200RhoGAP. It is a Rho GTPase-activating protein for Cdc42 and Rac1, and is implicated in the regulation of postsynaptic signaling and neurite outgrowth. PX-RICS, a variant of RICS that contain PX and SH3 domains, is the main isoform expressed during neural development. It is involved in neural functions including axon and dendrite extension, postnatal remodeling, and fine-tuning of neural circuits during early brain development. ARHGAP33, also called sorting nexin 26 or TCGAP (Tc10/CDC42 GTPase-activating protein), is widely expressed in the brain where it is involved in regulating the outgrowth of axons and dendrites and is regulated by the protein tyrosine kinase Fyn. It is translocated to the plasma membrane in adipocytes in response to insulin and may be involved in the regulation of insulin-stimulated glucose transport. 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.

Pssm-ID: 212769 [Multi-domain] Cd Length: 54 Bit Score: 43.59 E-value: 9.46e-06

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|.
gi 63055065 158 VVVADYQKQESSEISLSVGQVVDIIE---KNESGWWFVSTAEEQGWVPATC 205
Cdd:cd11835   3 HVIKRYTAQAPDELSLEVGDIVSVIDmppPEESTWWRGKKGFQVGFFPSEC 53

Src Homology 3 domain of Nephrocystin (or Nephrocystin-1); Nephrocystin contains an SH3 domain involved in signaling pathways that regulate cell adhesion and cytoskeletal organization. It is a protein that in humans is associated with juvenile nephronophthisis, an inherited kidney disease characterized by renal fibrosis that lead to chronic renal failure in children. It is localized in cell-cell junctions in renal duct cells, and is known to interact with Ack1, an activated Cdc42-associated kinase. 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.

Pssm-ID: 212704 [Multi-domain] Cd Length: 54 Bit Score: 43.46 E-value: 1.07e-05

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|...
gi 63055065 226 YTVIYPYTARDQDEMNLERGAVVEVVQKNLEGWWKI-RYQGKEGWAPASYLKK 277
Cdd:cd11770   2 YEALSDFQAEQEGDLSFKKGEVLRIISKRADGWWLAeNSKGNRGLVPKTYLKV 54

First Src homology 3 domain of the RhoGEF kinase, Kalirin; Kalirin, also called Duo, Duet, or TRAD, is a large neuronal dual Rho guanine nucleotide exchange factor (RhoGEF) that activates Rac1, RhoA, and RhoG using two RhoGEF domains. Kalirin exists in many isoforms generated by alternative splicing and the use of multiple promoters; the major isoforms are kalirin-7, -9, and -12, which differ at their C-terminal ends. Kalirin-12, the longest isoform, contains an N-terminal Sec14p domain, spectrin-like repeats, two RhoGEF domains, two SH3 domains, as well as Ig, FNIII, and kinase domains at the C-terminal end. Kalirin-7 contains only a single RhoGEF domain and does not contain an SH3 domain. Kalirin, through its many isoforms, interacts with many different proteins and is able to localize to different locations within the cell. It influences neurite initiation, axon growth, dendritic morphogenesis, vesicle trafficking, neuronal maintenance, and neurodegeneration. 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.

Pssm-ID: 212786 Cd Length: 62 Bit Score: 43.92 E-value: 1.08e-05

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|
gi 63055065 155 EQYVVVADYQKQESSEISLSVGQVVDIIEKNES--GWWFVSTAEE------QGWVPATCL 206
Cdd:cd11852   1 ELTVVIEDFEATSSQELTVSKGQTVEVLERPSSrpDWCLVRTLEQdnsppqEGLVPSSIL 60

Src Homology 3 domain of fungal peroxisomal membrane protein Pex13p; Pex13p, located in the peroxisomal membrane, contains two transmembrane regions and a C-terminal SH3 domain. It binds to the peroxisomal targeting type I (PTS1) receptor Pex5p and the docking factor Pex14p through its SH3 domain. It is essential for both PTS1 and PTS2 protein import pathways into the peroxisomal matrix. Pex13p binds Pex14p, which contains a PxxP motif, in a classical fashion to the proline-rich ligand binding site of its SH3 domain. It binds the WxxxF/Y motif of Pex5p in a novel site that does not compete with Pex14p binding. 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.

Pssm-ID: 212705 [Multi-domain] Cd Length: 60 Bit Score: 43.42 E-value: 1.20e-05

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*
gi 63055065 228 VIYPYTARDQD-EMNLERGAVVEVVQK-----NLEGWWKIRYQ-GKEGWAPASYL 275
Cdd:cd11771   4 ALYDFTPENPEmELSLKKGDIVAVLSKtdplgRDSEWWKGRTRdGRIGWFPSNYV 58

Fifth Src homology 3 domain (or SH3E) of Intersectin-1; Intersectin-1 (ITSN1) is an adaptor protein that functions in exo- and endocytosis, actin cytoskeletal reorganization, and signal transduction. It plays a role in clathrin-coated pit (CCP) formation. It binds to many proteins through its multidomain structure and facilitate the assembly of multimeric complexes. ITSN1 localizes in membranous organelles, CCPs, the Golgi complex, and may be involved in the cell membrane trafficking system. It exists in alternatively spliced short and long isoforms. The short isoform contains two Eps15 homology domains (EH1 and EH2), a coiled-coil region and five SH3 domains (SH3A-E), while the long isoform, in addition, contains RhoGEF (also called Dbl-homologous or DH), Pleckstrin homology (PH) and C2 domains. 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.

Pssm-ID: 212928 [Multi-domain] Cd Length: 54 Bit Score: 43.02 E-value: 1.47e-05

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*...
gi 63055065 229 IYPYTARDQDEMNLERGAVVEVVQKNLEGWWKIRYQGKEGWAPASYLK 276
Cdd:cd11995   6 MYDYTAQNDDELAFSKGQIINVLNKEDPDWWKGELNGQVGLFPSNYVK 53

Src Homology 3 domain of Mixed Lineage Kinases 1, 2, and 3; MLKs 1, 2, and 3 are Serine/Threonine Kinases (STKs), 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. Little is known about the specific function of MLK1, also called MAP3K9. It is capable of activating the c-Jun N-terminal kinase pathway. Mice lacking both MLK1 and MLK2 are viable, fertile, and have normal life spans. MLK2, also called MAP3K10, is abundant in brain, skeletal muscle, and testis. It functions upstream of the MAPK, c-Jun N-terminal kinase. It binds hippocalcin, a calcium-sensor protein that protects neurons against calcium-induced cell death. Both MLK2 and hippocalcin may be associated with the pathogenesis of Parkinson's disease. MLK3, also called MAP3K11, is highly expressed in breast cancer cells and its signaling through c-Jun N-terminal kinase has been implicated in the migration, invasion, and malignancy of cancer cells. It also functions as a negative regulator of Inhibitor of Nuclear Factor-KappaB Kinase (IKK) and thus, impacts inflammation and immunity. MLKs contain 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.

Pssm-ID: 212992 [Multi-domain] Cd Length: 58 Bit Score: 43.22 E-value: 1.50e-05

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                ....*....|....*....|....*....|....*....|....*....|....
gi 63055065 226 YTVIYPYTARDQDEMNLERGAVVEVVQKNL-----EGWWKIRYQGKEGWAPASY 274
Cdd:cd12059   2 WTAVFDYEASAEDELTLRRGDRVEVLSKDSavsgdEGWWTGKINDRVGIFPSNY 55

Src Homology 3 domain of Sdc25/Cdc25 guanine nucleotide exchange factors; This subfamily is composed of the Saccharomyces cerevisiae guanine nucleotide exchange factors (GEFs) Sdc25 and Cdc25, and similar proteins. These GEFs regulate Ras by stimulating the GDP/GTP exchange on Ras. Cdc25 is involved in the Ras/PKA pathway that plays an important role in the regulation of metabolism, stress responses, and proliferation, depending on available nutrients and conditions. Proteins in this subfamily contain an N-terminal SH3 domain as well as REM (Ras exchanger motif) and RasGEF domains at the C-terminus. SH3 domains bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs; they play a role in the regulation of enzymes by intramolecular interactions, changing the subcellular localization of signal pathway components and mediate multiprotein complex assemblies.

Pssm-ID: 212816 Cd Length: 55 Bit Score: 43.04 E-value: 1.57e-05

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|...
gi 63055065 853 VAVANFEGDEDTS-SFQEGTVFEVREKNSSGWWFCQVLSGAPSWE-GWIPSNY 903
Cdd:cd11883   3 VALYDFTPKSKNQlSFKAGDIIYVLNKDPSGWWDGVIISSSGKVKrGWFPSNY 55

Second C-terminal Src homology 3 domain of Dynamin Binding Protein, also called Tuba, and similar domains; DNMBP or Tuba is a cdc42-specific guanine nucleotide exchange factor (GEF) that contains four N-terminal SH3 domains, a central RhoGEF [or Dbl homology (DH)] domain followed by a Bin/Amphiphysin/Rvs (BAR) domain, and two C-terminal SH3 domains. It provides a functional link between dynamin, Rho GTPase signaling, and actin dynamics. It plays an important role in regulating cell junction configuration. The C-terminal SH3 domains of DNMBP bind to N-WASP and Ena/VASP proteins, which are key regulatory proteins of the actin cytoskeleton. Also included in this subfamily is the second C-terminal SH3 domain of Rho guanine nucleotide exchange factor 37 (ARHGEF37), whose function is still unknown. 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.

Pssm-ID: 212734 [Multi-domain] Cd Length: 57 Bit Score: 43.13 E-value: 1.60e-05

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*.
gi 63055065 373 YYTIAEFQTTIPDGISFQAGLKVEVIEK-SLSG---WWYIQMEDKEGWAPATFIDK 424
Cdd:cd11800   2 YYALYTFEARSPGELSVTEGQVVTVLEKhDLKGnpeWWLVEDRGKQGYVPSNYLAK 57

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.

Pssm-ID: 212895 [Multi-domain] Cd Length: 54 Bit Score: 42.86 E-value: 1.92e-05

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|.
gi 63055065 158 VVVADYQKQESSEISLSVGQVVDIIEKNESGWWFVSTAE-EQGWVPATCLE 207
Cdd:cd11962   3 VVLYDYEKDEDNEIELVEGEIVTNIEMVDEDWWMGTNSKgESGLFPSNYVE 53

Src homology 3 domain of Phospholipase C (PLC) gamma 1; PLCgamma1 is widely expressed and is essential in growth and development. It is activated by the TrkA receptor tyrosine kinase and functions as a key regulator of cell differentiation. It is also the predominant PLCgamma in T cells and is required for T cell and NK cell function. 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. 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.

Pssm-ID: 212903 Cd Length: 60 Bit Score: 43.05 E-value: 2.06e-05

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|
gi 63055065 229 IYPYTARDQDEMNLERGAVVEVVQKNLEGWWKIRYQGKEG-WAPASYLKK 277
Cdd:cd11970   9 LFDYKAQREDELTFTKNAIIQNVEKQEGGWWRGDYGGKKQlWFPSNYVEE 58

Fourth (C-terminal) Src homology 3 domain of Tyrosine kinase substrate with four SH3 domains; Tks4, also called SH3 and PX domain-containing protein 2B (SH3PXD2B) or HOFI, is a Src substrate and scaffolding protein that plays an important role in the formation of podosomes and invadopodia, the dynamic actin-rich structures that are related to cell migration and cancer cell invasion. It is required in the formation of functional podosomes, EGF-induced membrane ruffling, and lamellipodia generation. It plays an important role in cellular attachment and cell spreading. Tks4 is essential for the localization of MT1-MMP (membrane-type 1 matrix metalloproteinase) to invadopodia. It contains an N-terminal Phox homology (PX) domain and four SH3 domains. This model characterizes the fourth (C-terminal) SH3 domain of Tks4. 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.

Pssm-ID: 212951 Cd Length: 56 Bit Score: 42.95 E-value: 2.07e-05

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....
gi 63055065 157 YVVVADYQKQESSEiSLSVGQVVDIIEKNESGWWFVSTAEE----QGWVPATCL 206
Cdd:cd12018   2 YVAVADFEGDEDTS-SFKEGTVFEVREKNSSGWWFCKVLSGgpvwEGWIPSNYL 54

Src homology 3 domain of Fyn and Yrk Protein Tyrosine Kinases; Fyn and Yrk (Yes-related kinase) are members of the Src subfamily of proteins, which are cytoplasmic (or non-receptor) PTKs. Fyn, together with Lck, plays a critical role in T-cell signal transduction by phosphorylating ITAM (immunoreceptor tyr activation motif) sequences on T-cell receptors, ultimately leading to the proliferation and differentiation of T-cells. In addition, Fyn is involved in the myelination of neurons, and is implicated in Alzheimer's and Parkinson's diseases. Yrk has been detected only in chickens. It is primarily found in neuronal and epithelial cells and in macrophages. It may play a role in inflammation and in response to injury. Src kinases 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). 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.

Pssm-ID: 212939 [Multi-domain] Cd Length: 56 Bit Score: 42.73 E-value: 2.09e-05

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*.
gi 63055065 850 SLYVAVANFEG-DEDTSSFQEGTVFEVREKNSSGWWFCQVLSGAPSweGWIPSNYL 904
Cdd:cd12006   1 TLFVALYDYEArTEDDLSFHKGEKFQILNSSEGDWWEARSLTTGET--GYIPSNYV 54

Src homology 3 domain of yeast cell fusion protein Fus1p; Fus1p is required at the cell surface for cell fusion during the mating response in yeast. It requires Bch1p and Bud7p, which are Chs5p-Arf1p binding proteins, for localization to the plasma membrane. It acts as a scaffold protein to assemble a cell surface complex which is involved in septum degradation and inhibition of the NOG pathway to promote cell fusion. The SH3 domain of Fus1p interacts with Bin1p, a formin that controls the assembly of actin cables in response to Cdc42 signaling. It has been shown to bind the motif, R(S/T)(S/T)SL, instead of PxxP motifs. 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.

Pssm-ID: 212788 [Multi-domain] Cd Length: 56 Bit Score: 42.69 E-value: 2.21e-05

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*.
gi 63055065 156 QYVVVADYQKQESSEISLSVGQVVDIIEKNESGWWFV----STAEEQGWVPATCLE 207
Cdd:cd11854   1 LMTVISTFEPSLDDELLIKVGETVRVLAEYDDGWCLVeradGLNGDRGMVPGECLQ 56

Src homology 3 domain of Protein arginine N-methyltransferase 2; PRMT2, also called HRMT1L1, belongs to the arginine methyltransferase protein family. It functions as a coactivator to both estrogen receptor alpha (ER-alpha) and androgen receptor (AR), presumably through arginine methylation. The ER-alpha transcription factor is involved in cell proliferation, differentiation, morphogenesis, and apoptosis, and is also implicated in the development and progression of breast cancer. PRMT2 and its variants are upregulated in breast cancer cells and may be involved in modulating the ER-alpha signaling pathway during formation of breast cancer. PRMT2 also plays a role in regulating the function of E2F transcription factors, which are critical cell cycle regulators, by binding to the retinoblastoma gene product (RB). It contains an N-terminal SH3 domain and an AdoMet binding 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.

Pssm-ID: 212740 [Multi-domain] Cd Length: 53 Bit Score: 42.76 E-value: 2.26e-05

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*..
gi 63055065 157 YVVVADYQKQESSEISLSVGQVVDIIEKNESGWWFVSTAEEQGWVPA 203
Cdd:cd11806   2 YVAIADFVATDDSQLSFESGDKLLVLRKPSVDWWWAEHNGCCGYIPA 48

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.

Pssm-ID: 212902 Cd Length: 55 Bit Score: 42.52 E-value: 2.26e-05

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*....
gi 63055065 229 IYPYTARDQDEMNLERGAVVEVVQKNLEGWWKIRYQGK-EGWAPASYLK 276
Cdd:cd11969   5 LYDYRAKRSDELSFCKGALIHNVSKETGGWWKGDYGGKvQHYFPSNYVE 53

C-terminal Src Homology 3 domain of LIM and SH3 domain protein 1; Lasp1 is a cytoplasmic protein that binds focal adhesion proteins and is involved in cell signaling, migration, and proliferation. It is overexpressed in several cancer cells including breast, ovarian, bladder, and liver. In cancer cells, it can be found in the nucleus; its degree of nuclear localization correlates with tumor size and poor prognosis. Lasp1 is a 36kD protein containing an N-terminal LIM domain, two nebulin repeats, and a C-terminal SH3 domain. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

Pssm-ID: 212867 [Multi-domain] Cd Length: 59 Bit Score: 42.68 E-value: 2.41e-05

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*
gi 63055065 224 EKYTVIYPYTARDQDEMNLERGAVVEVVQKNLEGWW--KIRYQGKEGWAPASYLK 276
Cdd:cd11934   3 KRYRAVYDYNAADEDEVSFQDGDTIVNVQQIDDGWMygTVERTGDTGMLPANYVE 57

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.

Pssm-ID: 212709 [Multi-domain] Cd Length: 57 Bit Score: 42.69 E-value: 2.53e-05

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*.
gi 63055065 155 EQYVVVADYQKQESSEISLSVGQVVDIIE-KNESGWWFVSTAE--EQGWVPATCLE 207
Cdd:cd11775   1 KRGKVLYDFDAQSDDELTVKEGDVVYILDdKKSKDWWMVENVStgKEGVVPASYIE 56

Src homology 3 domain of Obscurin and similar proteins; Obscurin is a giant muscle protein that is concentrated at the peripheries of Z-disks and M-lines. It binds small ankyrin I, a component of the sarcoplasmic reticulum (SR) membrane. It is associated with the contractile apparatus through binding with titin and sarcomeric myosin. It plays important roles in the organization and assembly of the myofibril and the SR. Obscurin has been observed as alternatively-spliced isoforms. The major isoform in sleletal muscle, approximately 800 kDa in size, is composed of many adhesion modules and signaling domains. It harbors 49 Ig and 2 FNIII repeats at the N-terminues, a complex middle region with additional Ig domains, an IQ motif, and a conserved SH3 domain near RhoGEF and PH domains, and a non-modular C-terminus with phosphorylation motifs. The obscurin gene also encodes two kinase domains, which are not part of the 800 kDa form of the protein, but is part of smaller spliced products that present in heart muscle. 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.

Pssm-ID: 212958 Cd Length: 63 Bit Score: 42.56 E-value: 2.59e-05

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*....
gi 63055065 157 YVVVADY--QKQESSEISLSVGQVVDIIEKNESGWWFVST------AEEQGWVPATCLE 207
Cdd:cd12025   4 YIVTADYtpDGADTEAIPLEEGQYVEVLDSAHPLKWLVRTkptkssPPRQGWVSPAYLE 62

C-terminal (or second) Src homology 3 domain of VAV2 protein; VAV2 is widely expressed and functions as a guanine nucleotide exchange factor (GEF) for RhoA, RhoB and RhoG and also activates Rac1 and Cdc42. It is implicated in many cellular and physiological functions including blood pressure control, eye development, neurite outgrowth and branching, EGFR endocytosis and degradation, and cell cluster morphology, among others. It has been reported to associate with Nek3. 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.

Pssm-ID: 212910 [Multi-domain] Cd Length: 58 Bit Score: 42.69 E-value: 2.74e-05

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|
gi 63055065 230 YPYTARDQDEMNLERGAVVEVVQK--NLEGWWKIRYQGKEGWAPASYLKK 277
Cdd:cd11977   7 YNFAARDMRELSLREGDVVRIYSRigGDQGWWKGETNGRIGWFPSTYVEE 56

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

Pssm-ID: 212757 [Multi-domain] Cd Length: 53 Bit Score: 42.33 E-value: 2.84e-05

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*.
gi 63055065 162 DYQKQESSEISLSVGQVVDIIEKNESGWWFVSTAEEQGWVPATCLE 207
Cdd:cd11823   7 SYTANREDELSLQPGDIIEVHEKQDDGWWLGELNGKKGIFPATYVE 52

Second Src Homology 3 domain (SH3B) 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 second SH3 domain (SH3B) of CD2AP. SH3B binds to c-Cbl in a site (TPSSRPLR is the core binding motif) distinct from the c-Cbl/SH3A 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.

Pssm-ID: 212987 [Multi-domain] Cd Length: 55 Bit Score: 42.26 E-value: 2.92e-05

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*...
gi 63055065 156 QYVVVADYQKQESSEISLSVGQVVDIIEKNESGWWFVSTAEEQGWVPA 203
Cdd:cd12054   2 QCKVLFEYVPQNEDELELKVGDIIDINEEVEEGWWSGTLNGKSGLFPS 49

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.

Pssm-ID: 212779 [Multi-domain] Cd Length: 52 Bit Score: 42.18 E-value: 3.16e-05

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*..
gi 63055065 230 YPYTARDQDEMNLERGAVVEVVQKNLEGWWKIRYQ--GKEGWAPASY 274
Cdd:cd11845   6 YDYEARTDDDLSFKKGDRLQILDDSDGDWWLARHLstGKEGYIPSNY 52

Src homology 3 domain of the Rho guanine nucleotide exchange factor ARHGEF9; ARHGEF9, also called PEM2 or collybistin, selectively activates Cdc42 by exchanging bound GDP for free GTP. It is highly expressed in the brain and it interacts with gephyrin, a postsynaptic protein associated with GABA and glycine receptors. Mutations in the ARHGEF9 gene cause X-linked mental retardation with associated features like seizures, hyper-anxiety, aggressive behavior, and sensory hyperarousal. ARHGEF9 contains a SH3 domain followed by RhoGEF (also called Dbl-homologous or DH) and Pleckstrin Homology (PH) domains. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

Pssm-ID: 212908 Cd Length: 62 Bit Score: 42.39 E-value: 3.23e-05

                        10        20        30
                ....*....|....*....|....*....|....*.
gi 63055065 387 ISFQAGLKVEVIEKSLSGWWYIQMEDKEGWAPATFI 422
Cdd:cd11975  21 LAFKAGDVIKVLDASNKDWWWGQIDDEEGWFPASFV 56

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.

Pssm-ID: 394975 [Multi-domain] Cd Length: 47 Bit Score: 41.81 E-value: 3.45e-05

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|
gi 63055065   853 VAVANFEG-DEDTSSFQEGTVFEVREKNSSGWWFCQVLSGApswEGWIPS 901
Cdd:pfam00018   1 VALYDYTAqEPDELSFKKGDIIIVLEKSEDGWWKGRNKGGK---EGLIPS 47

Src homology 3 domain of CAS (Crk-Associated Substrate) scaffolding protein family member 4; CASS4, also called HEPL (HEF1-EFS-p130Cas-like), localizes to focal adhesions and plays a role in regulating FAK activity, focal adhesion integrity, and cell spreading. It is most abundant in blood cells and lung tissue, and is also found in high levels in leukemia and ovarian cell lines. CAS proteins function as molecular scaffolds to regulate protein complexes that are involved in many cellular processes. They share a common domain structure that includes an N-terminal SH3 domain, an unstructured substrate domain that contains many YxxP motifs, a serine-rich four-helix bundle, and a FAT-like C-terminal domain. The SH3 domain of CAS proteins binds to diverse partners including FAK, FRNK, Pyk2, PTP-PEST, DOCK180, 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.

Pssm-ID: 212933 Cd Length: 57 Bit Score: 42.17 E-value: 3.64e-05

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|.
gi 63055065 229 IYPYTARDQDEMNLERGAVVEVVQKNL---EGWWKIRYQGKEGWAPASYLK 276
Cdd:cd12000   6 LYDNKADCSDELAFRRGDILTVLEQNVpgsEGWWKCLLHGRQGLAPANRLQ 56

Src Homology 3 domain of Sorting Nexin 9 and similar proteins; Sorting nexins (SNXs) are Phox homology (PX) domain containing proteins that are involved in regulating membrane traffic and protein sorting in the endosomal system. SNXs differ from each other in their lipid-binding specificity, subcellular localization and specific function in the endocytic pathway. This subfamily consists of SH3 domain containing SNXs including SNX9, SNX18, SNX33, and similar proteins. SNX9 is localized to plasma membrane endocytic sites and acts primarily in clathrin-mediated endocytosis, while SNX18 is localized to peripheral endosomal structures, and acts in a trafficking pathway that is clathrin-independent but relies on AP-1 and PACS1. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

Pssm-ID: 212697 [Multi-domain] Cd Length: 55 Bit Score: 41.93 E-value: 4.18e-05

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|..
gi 63055065 225 KYTVIYPYTARDQDEMNLERGAVVEVVQKN-LEGWWKIR-YQGKEGWAPASY 274
Cdd:cd11763   1 KVRALYDFDSQPSGELSLRAGEVLTITRQDvGDGWLEGRnSRGEVGLFPSSY 52

Second Src homology 3 domain of Tyrosine kinase substrate with four SH3 domains; Tks4, also called SH3 and PX domain-containing protein 2B (SH3PXD2B) or HOFI, is a Src substrate and scaffolding protein that plays an important role in the formation of podosomes and invadopodia, the dynamic actin-rich structures that are related to cell migration and cancer cell invasion. It is required in the formation of functional podosomes, EGF-induced membrane ruffling, and lamellipodia generation. It plays an important role in cellular attachment and cell spreading. Tks4 is essential for the localization of MT1-MMP (membrane-type 1 matrix metalloproteinase) to invadopodia. It contains an N-terminal Phox homology (PX) domain and four SH3 domains. This model characterizes the second SH3 domain of Tks4. 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.

Pssm-ID: 213009 [Multi-domain] Cd Length: 54 Bit Score: 41.94 E-value: 4.67e-05

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*.
gi 63055065 861 DEDTSSFQEGTVFEVREKNSSGWWFCQVLSGapswEGWIPSNYLRK 906
Cdd:cd12076  13 DQDEINLEKGAVVEVIQKNLEGWWKIRYQGK----EGWAPASYLKK 54

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

Pssm-ID: 394975 [Multi-domain] Cd Length: 47 Bit Score: 41.42 E-value: 4.77e-05

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*
gi 63055065   376 IAEFQTTIPDGISFQAGLKVEVIEKSLSGWWYIQM-EDKEGWAPA 419
Cdd:pfam00018   3 LYDYTAQEPDELSFKKGDIIIVLEKSEDGWWKGRNkGGKEGLIPS 47

Src Homology 3 domain of Cdc42-Interacting Protein 4; This subfamily is composed of Cdc42-Interacting Protein 4 (CIP4), Formin Binding Protein 17 (FBP17), FormiN Binding Protein 1-Like (FNBP1L), and similar proteins. CIP4 and FNBP1L are Cdc42 effectors that bind Wiskott-Aldrich syndrome protein (WASP) and function in endocytosis. CIP4 and FBP17 bind to the Fas ligand and may be implicated in the inflammatory response. CIP4 may also play a role in phagocytosis. It functions downstream of Cdc42 in PDGF-dependent actin reorganization and cell migration, and also regulates the activity of PDGFRbeta. It uses Src as a substrate in regulating the invasiveness of breast tumor cells. CIP4 may also play a role in the pathogenesis of Huntington's disease. Members of this subfamily typically contain an N-terminal F-BAR (FES-CIP4 Homology and Bin/Amphiphysin/Rvs) domain, a central Cdc42-binding HR1 domain, and a C-terminal SH3 domain. The SH3 domain of CIP4 associates with Gapex-5, a Rab31 GEF. 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.

Pssm-ID: 212844 [Multi-domain] Cd Length: 55 Bit Score: 41.48 E-value: 4.93e-05

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|..
gi 63055065 227 TVIYPYTARDQDEMNLERGAVVEVVQK-NLEGWWKIRY-QGKEGWAPASYLK 276
Cdd:cd11911   3 TALYDFDGTSEGTLSMEEGEILLVLEEdGGDGWTRVRKnNGDEGYVPTSYIE 54

Third Src Homology 3 domain (SH3C) of CD2-associated protein; CD2AP, also called CMS (Cas ligand with Multiple SH3 domains) or METS1 (Mesenchyme-to-Epithelium Transition protein with SH3 domains), is a cytosolic adaptor protein that plays a role in regulating the cytoskeleton. It is critical in cell-to-cell union necessary for kidney function. It also stabilizes the contact between a T cell and antigen-presenting cells. It is primarily expressed in podocytes at the cytoplasmic face of the slit diaphragm and serves as a linker anchoring podocin and nephrin to the actin cytoskeleton. CD2AP contains three SH3 domains, a proline-rich region, and a C-terminal coiled-coil domain. All of these domains enable CD2AP to bind various protein partners and assemble complexes that have been implicated in many different functions. This alignment model represents the third SH3 domain (SH3C) of CD2AP. SH3C has been shown to bind ubiquitin. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

Pssm-ID: 212989 [Multi-domain] Cd Length: 57 Bit Score: 41.73 E-value: 5.03e-05

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*...
gi 63055065 229 IYPYTARDQDEMNLERGAVVEVVQKNL--EGWWKIRYQGKEGWAPASY 274
Cdd:cd12056   7 LFHYEGTNEDELDFKEGEIILIISKDTgePGWWKGELNGKEGVFPDNF 54

Src Homology 3 domain of Interleukin-2-inducible T-cell Kinase; ITK (also known as Tsk or Emt) is a cytoplasmic (or nonreceptor) tyr kinase containing Src homology protein interaction domains (SH3, SH2) N-terminal to the catalytic tyr kinase domain. It also contains an N-terminal pleckstrin homology (PH) domain, which binds the products of PI3K and allows membrane recruitment and activation, and the Tec homology (TH) domain, which contains proline-rich and zinc-binding regions. ITK is expressed in T-cells and mast cells, and is important in their development and differentiation. Of the three Tec kinases expressed in T-cells, ITK plays the predominant role in T-cell receptor (TCR) signaling. It is activated by phosphorylation upon TCR crosslinking and is involved in the pathway resulting in phospholipase C-gamma1 activation and actin polymerization. It also plays a role in the downstream signaling of the T-cell costimulatory receptor CD28, the T-cell surface receptor CD2, and the chemokine receptor CXCR4. In addition, ITK is crucial for the development of T-helper(Th)2 effector responses. 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.

Pssm-ID: 212841 [Multi-domain] Cd Length: 56 Bit Score: 41.92 E-value: 5.03e-05

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*...
gi 63055065 229 IYPYTARDQDEMNLERGAVVEVVQKNLEGWWKIR-YQGKEGWAPASYL 275
Cdd:cd11908   6 LYDYQTNDPQELALRYNEEYHLLDSSEIHWWRVQdKNGHEGYVPSSYL 53

Fourth Src homology 3 domain of Tyrosine kinase substrate with five SH3 domains; Tks5, also called SH3 and PX domain-containing protein 2A (SH3PXD2A) or Five SH (FISH), is a scaffolding protein and Src substrate that is localized in podosomes, which are electron-dense structures found in Src-transformed fibroblasts, osteoclasts, macrophages, and some invasive cancer cells. It binds and regulates some members of the ADAMs family of transmembrane metalloproteases, which function as sheddases and mediators of cell and matrix interactions. It is required for podosome formation, degradation of the extracellular matrix, and cancer cell invasion. Tks5 contains an N-terminal Phox homology (PX) domain and five SH3 domains. This model characterizes the fourth SH3 domain of Tks5. 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.

Pssm-ID: 212952 Cd Length: 53 Bit Score: 41.50 E-value: 5.87e-05

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*
gi 63055065 851 LYVAVANFEGDEDTS-SFQEGTVFEVREKNSSGWWFCQVlsgaPSWEGWIPSNYL 904
Cdd:cd12019   1 SYMTTSAYQKVQDSEiSFPAGVEVEVLEKQESGWWYVRF----GELEGWAPSHYL 51

Third Src Homology 3 domain of Nck2 adaptor protein; Nck2 (also called Nckbeta or Growth factor receptor-bound protein 4, Grb4) plays a crucial role in connecting signaling pathways of tyrosine kinase receptors and important effectors in actin dynamics and cytoskeletal remodeling. It binds neuronal signaling proteins such as ephrinB and Disabled-1 (Dab-1) exclusively. Nck adaptor proteins regulate actin cytoskeleton dynamics by linking proline-rich effector molecules to protein tyrosine kinases and phosphorylated signaling intermediates. They contain three SH3 domains and a C-terminal SH2 domain. They function downstream of the PDGFbeta receptor and are involved in Rho GTPase signaling and actin dynamics. Vertebrates contain two Nck adaptor proteins: Nck1 (also called Nckalpha) and Nck2, which show partly overlapping functions but also bind distinct targets. The third SH3 domain of Nck appears to prefer ligands with a PxAPxR motif. SH3 domains are protein interaction domains that usually bind to proline-rich ligands with moderate affinity and selectivity, preferentially a PxxP motif. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

Pssm-ID: 212836 [Multi-domain] Cd Length: 59 Bit Score: 41.58 E-value: 6.87e-05

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|
gi 63055065 229 IYPYTARDQDEMNLERGAVVEVVQK--NLEGWWKIR-YQGKEGWAPASYL 275
Cdd:cd11903   6 LYPFSSVTEEELNFEKGETMEVIEKpeNDPEWWKCKnSRGQVGLVPKNYV 55

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.

Pssm-ID: 212709 [Multi-domain] Cd Length: 57 Bit Score: 41.15 E-value: 7.09e-05

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|...
gi 63055065 227 TVIYPYTARDQDEMNLERGAVVEVV-QKNLEGWWKIRYQ--GKEGWAPASYLK 276
Cdd:cd11775   4 KVLYDFDAQSDDELTVKEGDVVYILdDKKSKDWWMVENVstGKEGVVPASYIE 56

C-terminal Src Homology 3 domain of Nebulette and LIM-nebulette (or Lasp2); Nebulette is a cardiac-specific protein that localizes to the Z-disc. It interacts with tropomyosin and is important in stabilizing actin thin filaments in cardiac muscles. Polymorphisms in the nebulette gene are associated with dilated cardiomyopathy, with some mutations resulting in severe heart failure. Nebulette is a 107kD protein that contains an N-terminal acidic region, multiple nebulin repeats, and a C-terminal SH3 domain. LIM-nebulette, also called Lasp2 (LIM and SH3 domain protein 2), is an alternatively spliced variant of nebulette. Although it shares a gene with nebulette, Lasp2 is not transcribed from a muscle-specific promoter, giving rise to its multiple tissue expression pattern with highest amounts in the brain. It can crosslink actin filaments and it affects cell spreading. Lasp2 is a 34kD protein containing an N-terminal LIM domain, three 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.

Pssm-ID: 212868 [Multi-domain] Cd Length: 58 Bit Score: 41.14 E-value: 7.59e-05

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|...
gi 63055065 226 YTVIYPYTARDQDEMNLERGAVVEVVQKNLEGWW--KIRYQGKEGWAPASYLK 276
Cdd:cd11935   3 YRAMYDYSAQDEDEVSFRDGDYIVNVQPIDEGWMygTVQRTGRTGMLPANYIE 55

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.

Pssm-ID: 212810 [Multi-domain] Cd Length: 53 Bit Score: 41.15 E-value: 7.82e-05

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*.
gi 63055065 851 LYVAVANFEG-DEDTSSFQEGTVFEVREKNSSGWWFcQVLSGApswEGWIPSNYLR 905
Cdd:cd11877   1 LVRAKFNFEGtNEDELSFDKGDIITVTQVVEGGWWE-GTLNGK---TGWFPSNYVK 52

First 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 first 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.

Pssm-ID: 212845 [Multi-domain] Cd Length: 55 Bit Score: 41.06 E-value: 8.85e-05

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|.
gi 63055065 159 VVADYQKQESSEISLSVGQVVDIIEKNE-SGWWFV-STAEEQGWVPATCLE 207
Cdd:cd11912   4 VLYDYTASGDDEVSISEGEEVTVLEPDDgSGWTKVrNGSGEEGLVPTSYIE 54

Second Src homology 3 domain (or SH3B) of Intersectin-1; Intersectin-1 (ITSN1) is an adaptor protein that functions in exo- and endocytosis, actin cytoskeletal reorganization, and signal transduction. It plays a role in clathrin-coated pit (CCP) formation. It binds to many proteins through its multidomain structure and facilitate the assembly of multimeric complexes. ITSN1 localizes in membranous organelles, CCPs, the Golgi complex, and may be involved in the cell membrane trafficking system. It exists in alternatively spliced short and long isoforms. The short isoform contains two Eps15 homology domains (EH1 and EH2), a coiled-coil region and five SH3 domains (SH3A-E), while the long isoform, in addition, contains RhoGEF (also called Dbl-homologous or DH), Pleckstrin homology (PH) and C2 domains. The second SH3 domain (or SH3B) of ITSN1 has been shown to bind WNK and CdGAP. 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.

Pssm-ID: 212922 [Multi-domain] Cd Length: 52 Bit Score: 40.85 E-value: 9.04e-05

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*...
gi 63055065 229 IYPYTARDQDEMNLERGAVVEVVQKNlEGWWKIRYQGKEGWAPASYLK 276
Cdd:cd11989   5 LYPWRAKKDNHLNFNKNDVITVLEQQ-DMWWFGEVQGQKGWFPKSYVK 51

Src homology 3 domain of Slit-Robo GTPase Activating Proteins; Slit-Robo GTPase Activating Proteins (srGAPs) are Rho GAPs that interact with Robo1, the transmembrane receptor of Slit proteins. Slit proteins are secreted proteins that control axon guidance and the migration of neurons and leukocytes. Vertebrates contain three isoforms of srGAPs (srGAP1-3), all of which are expressed during embryonic and early development in the nervous system but with different localization and timing. A fourth member has also been reported (srGAP4, also called ARHGAP4). srGAPs contain an N-terminal F-BAR domain, a Rho GAP 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.

Pssm-ID: 212743 [Multi-domain] Cd Length: 53 Bit Score: 40.85 E-value: 9.60e-05

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*.
gi 63055065 230 YPYTARDQDEMNLERGAVVEVVQKNLEGWWKIRYQGKEGWAPASYL 275
Cdd:cd11809   6 FDYTGRSERELSFKKGDSLTLYRQVSDDWWRGQLNGQDGLVPHKYI 51

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.

Pssm-ID: 429575 [Multi-domain] Cd Length: 54 Bit Score: 40.66 E-value: 1.05e-04

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|....*.
gi 63055065   852 YVAVANFEG-DEDTSSFQEGTVFEVREKNSSGWWFCQVLSGapswEGWIPSNYLRK 906
Cdd:pfam07653   2 GRVIFDYVGtDKNGLTLKKGDVVKVLGKDNDGWWEGETGGR----VGLVPSTAVEE 53

Src Homology 3 domain of Sdc25/Cdc25 guanine nucleotide exchange factors; This subfamily is composed of the Saccharomyces cerevisiae guanine nucleotide exchange factors (GEFs) Sdc25 and Cdc25, and similar proteins. These GEFs regulate Ras by stimulating the GDP/GTP exchange on Ras. Cdc25 is involved in the Ras/PKA pathway that plays an important role in the regulation of metabolism, stress responses, and proliferation, depending on available nutrients and conditions. Proteins in this subfamily contain an N-terminal SH3 domain as well as REM (Ras exchanger motif) and RasGEF domains at the C-terminus. SH3 domains bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs; they play a role in the regulation of enzymes by intramolecular interactions, changing the subcellular localization of signal pathway components and mediate multiprotein complex assemblies.

Pssm-ID: 212816 Cd Length: 55 Bit Score: 40.73 E-value: 1.05e-04

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|..
gi 63055065 158 VVVA--DYQKQESSEISLSVGQVVDIIEKNESGWW--FV---STAEEQGWVP 202
Cdd:cd11883   1 VVVAlyDFTPKSKNQLSFKAGDIIYVLNKDPSGWWdgVIissSGKVKRGWFP 52

Src homology 3 domain of SH3 and multiple ankyrin repeat domains protein 2; Shank2, also called ProSAP1 (Proline-rich synapse-associated protein 1) or CortBP1 (Cortactin-binding protein 1), is found in neurons, glia, endocrine cells, liver, and kidney. It plays a role in regulating dendritic spine volume and branching and postsynaptic clustering. Mutations in the Shank2 gene are associated with autism spectrum disorder and mental retardation. Shank proteins carry scaffolding functions through multiple sites of protein-protein interaction in its domain architecture, including ankyrin (ANK) repeats, a long proline rich region, as well as SH3, PDZ, and SAM domains. The SH3 domain of Shank binds GRIP, a scaffold protein that binds AMPA receptors and Eph receptors/ligands. 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.

Pssm-ID: 212916 Cd Length: 52 Bit Score: 40.68 E-value: 1.13e-04

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|
gi 63055065 157 YVVVADYQKQESSEISLSVGQVVDIIEKNESGWWFVSTAEEQGWVPATCL 206
Cdd:cd11983   3 FVVVKSYQPQVEGEIPLHKGDRVKVLSIGEGGFWEGSARGHVGWFPAECV 52

Third Src Homology 3 domain of SH3 domain containing ring finger 1 (SH3RF1), SH3RF3, and similar domains; SH3RF1 (or POSH) and SH3RF3 (or POSH2) are scaffold proteins that function as E3 ubiquitin-protein ligases. They contain an N-terminal RING finger domain and four SH3 domains. This model represents the third SH3 domain, located in the middle of SH3RF1 and SH3RF3, and similar domains. SH3RF1 plays a role in calcium homeostasis through the control of the ubiquitin domain protein Herp. It may also have a role in regulating death receptor mediated and JNK mediated apoptosis. SH3RF3 interacts with p21-activated kinase 2 (PAK2) and GTP-loaded Rac1. It may play a role in regulating JNK mediated apoptosis in certain conditions. 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.

Pssm-ID: 212717 [Multi-domain] Cd Length: 55 Bit Score: 40.46 E-value: 1.15e-04

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....
gi 63055065 226 YTVIYPYTARDQDEMNLERGAVVEVVQKNLEGWWK---IRyQGKEGWAPASYLK 276
Cdd:cd11783   2 YVALYPYKPQKPDELELRKGEMYTVTEKCQDGWFKgtsLR-TGQSGVFPGNYVQ 54

Src homology 3 domain of Type I fungal Myosins; Type I myosins (myosin-I) are actin-dependent motors in endocytic actin structures and actin patches. They play roles in membrane traffic in endocytic and secretory pathways, cell motility, and mechanosensing. Saccharomyces cerevisiae has two myosins-I, Myo3 and Myo5, which are involved in endocytosis and the polarization of the actin cytoskeleton. Myosin-I contains an N-terminal actin-activated ATPase, a phospholipid-binding TH1 (tail homology 1) domain, and a C-terminal extension which includes an F-actin-binding TH2 domain, an SH3 domain, and an acidic peptide that participates in activating the Arp2/3complex. The SH3 domain of myosin-I is required for myosin-I-induced actin polymerization. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

Pssm-ID: 212792 [Multi-domain] Cd Length: 55 Bit Score: 40.45 E-value: 1.21e-04

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*..
gi 63055065 378 EFQTTIPDGISFQAGLKVEVIEKSLSGWWYIQM--EDKEGWAPATFI 422
Cdd:cd11858   7 DFAGSVANELSLKKDDIVYIVQKEDNGWWLAKKldESKEGWVPAAYL 53

Src Homology 3 domain of beta-Pak Interactive eXchange factor; Beta-PIX, also called Rho guanine nucleotide exchange factor 7 (ARHGEF7) or Cool (Cloned out of Library)-1, activates small GTPases by exchanging bound GDP for free GTP. It acts as a GEF for both Cdc42 and Rac 1, and plays important 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.

Pssm-ID: 212994 [Multi-domain] Cd Length: 54 Bit Score: 40.44 E-value: 1.23e-04

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                ....*....|....*....|....*....|....*....|....*....|.
gi 63055065 857 NFE-GDEDTSSFQEGTVFEVREKNSSGWWFcQVLSGApswEGWIPSNYLRK 906
Cdd:cd12061   7 NFQqTNEDELSFSKGDVIHVTRVEEGGWWE-GTHNGR---TGWFPSNYVRE 53

Src homology 3 domain of the Rho guanine nucleotide exchange factor, ephexin-1 (also called NGEF or ARHGEF27); Ephexin-1, also called NGEF (neuronal GEF) or ARHGEF27, activates RhoA, Tac1, and Cdc42 by exchanging bound GDP for free GTP. It is expressed mainly in the brain in a region associated with movement control. It regulates the stability of postsynaptic acetylcholine receptor (AChR) clusters and thus, plays a critical role in the maturation and neurotransmission of neuromuscular junctions. Ephexin-1 directly interacts with the ephrin receptor EphA4 and their coexpression enhances the ability of ephexin-1 to activate RhoA. It is required for normal axon growth and EphA-induced growth cone collapse. Ephexin-1 contains RhoGEF (also called Dbl-homologous or DH), Pleckstrin Homology (PH), and SH3 domains. The SH3 domains of ARHGEFs play an autoinhibitory role through intramolecular interactions with a proline-rich region N-terminal to the DH domain. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

Pssm-ID: 212872 [Multi-domain] Cd Length: 55 Bit Score: 40.70 E-value: 1.32e-04

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                ....*....|....*....|....*....|....*....|....*....|....
gi 63055065 156 QYVVVADYQKQESSEISLSVGQVVDIIEKNESGWWFVSTA--EEQGWVPATCLE 207
Cdd:cd11939   1 QVQCVHPYVSQEPDELSLELADVLNILDKTDDGWIFGERLhdQERGWFPSSVVE 54

Third Src Homology 3 domain of SH3 domain containing ring finger 2; SH3RF2 is also called POSHER (POSH-eliminating RING protein) or HEPP1 (heart protein phosphatase 1-binding protein). It acts as an anti-apoptotic regulator of the JNK pathway by binding to and promoting the degradation of SH3RF1 (or POSH), a scaffold protein that is required for pro-apoptotic JNK activation. It may also play a role in cardiac functions together with protein phosphatase 1. SH3RF2 contains an N-terminal RING finger domain and three SH3 domains. This model represents the third SH3 domain, located in the middle, of SH3RF2. 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.

Pssm-ID: 212718 Cd Length: 55 Bit Score: 40.53 E-value: 1.33e-04

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                ....*....|....*....|....*....|....*....|....*....|..
gi 63055065 226 YTVIYPYTARDQDEMNLERGAVVEVVQKNLEGWWK--IRYQGKEGWAPASYL 275
Cdd:cd11784   2 CVALHSYSAHRPEELELQKGEGVRVLGKFQEGWLRglSLVTGRVGIFPSNYV 53

Src homology 3 domain of Brk (Breast tumor kinase) Protein Tyrosine Kinase (PTK), also called PTK6; Brk is a cytoplasmic (or non-receptor) PTK with limited homology to Src kinases. It has been found to be overexpressed in a majority of breast tumors. It plays roles in normal cell differentiation, proliferation, survival, migration, and cell cycle progression. Brk substrates include RNA-binding proteins (SLM-1/2, Sam68), transcription factors (STAT3/5), and signaling molecules (Akt, paxillin, IRS-4). Src kinases in general 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 site. 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.

Pssm-ID: 212781 [Multi-domain] Cd Length: 58 Bit Score: 40.62 E-value: 1.38e-04

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                ....*....|....*....|....*....|....*....|....*....|....*...
gi 63055065 851 LYVAVANFE--GDEDTSsFQEGTVFEVREKnSSGWWFCQVL--SGAPSWEGWIPSNYL 904
Cdd:cd11847   1 IYKALWDFKarGDEELS-FQAGDQFRIAER-SGDWWTALKLdrAGGVVAQGFVPNNYL 56

Src homology 3 domain of Abl Interactor 1; Abi1, also called e3B1, is a central regulator of actin cytoskeletal reorganization through interactions with many protein complexes. It is part of WAVE, a nucleation-promoting factor complex, that links Rac 1 activation to actin polymerization causing lamellipodia protrusion at the plasma membrane. Abi1 interact with formins to promote protrusions at the leading edge of motile cells. It also is a target of alpha4 integrin, regulating membrane protrusions at sites of integrin engagement. 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. 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.

Pssm-ID: 212904 [Multi-domain] Cd Length: 59 Bit Score: 40.39 E-value: 1.52e-04

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                ....*....|....*....|....*....|....*....|....*....|..
gi 63055065 225 KYTVIYPYTARDQDEMNLERGAVVEVVQKNLEGWWKIRYQGKEGWAPASYLK 276
Cdd:cd11971   1 KVVAIYDYSKDKDDELSFMEGAIIYVIKKNDDGWYEGVCNGVTGLFPGNYVE 52

Fourth (C-terminal) Src homology 3 domain of Tyrosine kinase substrate with four SH3 domains; Tks4, also called SH3 and PX domain-containing protein 2B (SH3PXD2B) or HOFI, is a Src substrate and scaffolding protein that plays an important role in the formation of podosomes and invadopodia, the dynamic actin-rich structures that are related to cell migration and cancer cell invasion. It is required in the formation of functional podosomes, EGF-induced membrane ruffling, and lamellipodia generation. It plays an important role in cellular attachment and cell spreading. Tks4 is essential for the localization of MT1-MMP (membrane-type 1 matrix metalloproteinase) to invadopodia. It contains an N-terminal Phox homology (PX) domain and four SH3 domains. This model characterizes the fourth (C-terminal) SH3 domain of Tks4. 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.

Pssm-ID: 212951 Cd Length: 56 Bit Score: 40.26 E-value: 1.73e-04

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*.
gi 63055065 236 DQDEMNLERGAVVEVVQKNLEGWW--KIRYQGK--EGWAPASYLKK 277
Cdd:cd12018  11 DEDTSSFKEGTVFEVREKNSSGWWfcKVLSGGPvwEGWIPSNYLRK 56

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.

Pssm-ID: 212723 [Multi-domain] Cd Length: 55 Bit Score: 39.99 E-value: 1.80e-04

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*
gi 63055065 225 KYTVIYPYTARDQDEMNLERGAVVEVVQKNLEGWWKIRYQ--GKEGWAPASYLKK 277
Cdd:cd11789   1 RYRAMYDYAAADDDEVSFQEGDVIINVEIIDDGWMEGTVQrtGQSGMLPANYVEL 55

Second or C-terminal Src homology 3 domain of NADPH oxidase (Nox) Organizing protein 1; Nox Organizing protein 1 (NoxO1) is a critical regulator of enzyme kinetics of the nonphagocytic NADPH oxidase Nox1, which catalyzes the transfer of electrons from NADPH to molecular oxygen to form superoxide. Nox1 is expressed in colon, stomach, uterus, prostate, and vascular smooth muscle cells. NoxO1 is involved in targeting activator subunits (such as NoxA1) to Nox1. It is co-localized with Nox1 in the membranes of resting cells and directs the subcellular localization of Nox1. NoxO1 contains an N-terminal Phox homology (PX) domain, tandem SH3 domains (N-SH3 and C-SH3), and a C-terminal proline-rich region (PRR). This model characterizes the second SH3 domain (or C-SH3) of NoxO1. The tandem SH3 domains of NoxO1 interact with the PRR of p22phox, which also complexes with Nox1. 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.

Pssm-ID: 212957 Cd Length: 53 Bit Score: 40.01 E-value: 2.02e-04

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*.
gi 63055065 851 LYVAVANFEG-DEDTSSFQEGTVFEVREKNSSGWWFCQVLSGApsweGWIPSNYLR 905
Cdd:cd12024   1 LYYATRAYEAqKEDELSVPAGVVVEVLQKSDNGWWLIRYNGRA----GYVPSMYLQ 52

Src Homology 3 domain of alpha-Pak Interactive eXchange factor; Alpha-PIX, also called Rho guanine nucleotide exchange factor 6 (ARHGEF6) or Cool (Cloned out of Library)-2, activates small GTPases by exchanging bound GDP for free GTP. It acts as a GEF for both Cdc42 and Rac 1, and is localized in dendritic spines where it regulates spine morphogenesis. It controls dendritic length and spine density in the hippocampus. Mutations in the ARHGEF6 gene cause X-linked intellectual disability in humans. 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.

Pssm-ID: 212993 Cd Length: 58 Bit Score: 39.99 E-value: 2.09e-04

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*...
gi 63055065 230 YPYTARDQDEMNLERGAVVEVVQKNLEGWWKIRYQGKEGWAPASYLKK 277
Cdd:cd12060   8 FNFKQTNEDELSVCKGDIIYVTRVEEGGWWEGTLNGKTGWFPSNYVRE 55

Src Homology 3 domain of Nephrocystin (or Nephrocystin-1); Nephrocystin contains an SH3 domain involved in signaling pathways that regulate cell adhesion and cytoskeletal organization. It is a protein that in humans is associated with juvenile nephronophthisis, an inherited kidney disease characterized by renal fibrosis that lead to chronic renal failure in children. It is localized in cell-cell junctions in renal duct cells, and is known to interact with Ack1, an activated Cdc42-associated kinase. 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.

Pssm-ID: 212704 [Multi-domain] Cd Length: 54 Bit Score: 39.99 E-value: 2.13e-04

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|..
gi 63055065 372 EYYTIAEFQTTIPDGISFQAGLKVEVIEKSLSGWWYIQMED-KEGWAPATFI 422
Cdd:cd11770   1 LYEALSDFQAEQEGDLSFKKGEVLRIISKRADGWWLAENSKgNRGLVPKTYL 52

Src Homology 3 (SH3) domain of Inhibitor of ASPP protein (iASPP); iASPP, also called RelA-associated inhibitor (RAI), is an oncoprotein that inhibits the apoptotic transactivation potential of p53. It is upregulated in human breast cancers expressing wild-type p53, in acute leukemias regardless of the p53 mutation status, as well as in ovarian cancer where it is associated with poor patient outcome and chemoresistance. iASPP is also a binding partner and negative regulator of p65RelA, which promotes cell proliferation and inhibits apoptosis; p65RelA has the opposite effect on cell growth compared to the p53 family. It contains a proline-rich region, four ankyrin (ANK) repeats, and an SH3 domain at its C-terminal half. The SH3 domain and the ANK repeats of iASPP contribute to the p53 binding site; they bind to the DNA binding domain of p53. 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.

Pssm-ID: 212885 [Multi-domain] Cd Length: 56 Bit Score: 39.91 E-value: 2.52e-04

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*....
gi 63055065 229 IYPYTARDQDEMNLERGAVVEVVQKNLEG--WWKIRYQGKEGWAPASYL 275
Cdd:cd11952   6 LWDYSAEFPDELSFKEGDMVTVLRKDGEGtdWWWASLCGREGYVPRNYF 54

Src homology 3 domain of SH3 and multiple ankyrin repeat domains protein 3; Shank3, also called ProSAP2 (Proline-rich synapse-associated protein 2), is widely expressed. It plays a role in the formation of dendritic spines and synapses. Haploinsufficiency of the Shank3 gene causes the 22q13 deletion/Phelan-McDermid syndrome, and variants of Shank3 have been implicated in autism spectrum disorder, schizophrenia, and intellectual disability. Shank proteins carry scaffolding functions through multiple sites of protein-protein interaction in its domain architecture, including ankyrin (ANK) repeats, a long proline rich region, as well as SH3, PDZ, and SAM domains. The SH3 domain of Shank binds GRIP, a scaffold protein that binds AMPA receptors and Eph receptors/ligands. 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.

Pssm-ID: 212917 Cd Length: 52 Bit Score: 39.55 E-value: 2.55e-04

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|
gi 63055065 157 YVVVADYQKQESSEISLSVGQVVDIIEKNESGWWFVSTAEEQGWVPATCL 206
Cdd:cd11984   3 FIAVKAYSPQGEGEIQLNRGERVKVLSIGEGGFWEGTVKGRTGWFPADCV 52

Src homology 3 domain of CAS (Crk-Associated Substrate) scaffolding protein family member, Neural precursor cell Expressed, Developmentally Down-regulated 9; NEDD9 is also called human enhancer of filamentation 1 (HEF1) or CAS-L (Crk-associated substrate in lymphocyte). It was first described as a gene predominantly expressed in early embryonic brain, and was also isolated from a screen of human proteins that regulate filamentous budding in yeast, and as a tyrosine phosphorylated protein in lymphocytes. It promotes metastasis in different solid tumors. NEDD9 localizes in focal adhesions and associates with FAK and Abl kinase. It also interacts with SMAD3 and the proteasomal machinery which allows its rapid turnover; these interactions are not shared by other CAS proteins. CAS proteins function as molecular scaffolds to regulate protein complexes that are involved in many cellular processes. They share a common domain structure that includes an N-terminal SH3 domain, an unstructured substrate domain that contains many YxxP motifs, a serine-rich four-helix bundle, and a FAT-like C-terminal domain. The SH3 domain of CAS proteins binds to diverse partners including FAK, FRNK, Pyk2, PTP-PEST, DOCK180, 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.

Pssm-ID: 212935 Cd Length: 57 Bit Score: 39.58 E-value: 2.69e-04

                        10        20        30        40
                ....*....|....*....|....*....|....*....|..
gi 63055065 238 DEMNLERGAVVEVVQKN---LEGWWKIRYQGKEGWAPASYLK 276
Cdd:cd12002  14 EELAFRKGDILTVIEQNtggLEGWWLCSLHGRQGIAPGNRLK 55

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

Pssm-ID: 212700 [Multi-domain] Cd Length: 53 Bit Score: 39.56 E-value: 2.74e-04

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*.
gi 63055065 379 FQTTIPDGISFQAGLKVEVIEKSLSGWWYIQMEDKEGWAPATFIDK 424
Cdd:cd11766   8 YEAQREDELSLRKGDRVLVLEKSSDGWWRGECNGQVGWFPSNYVTE 53

The phosphoinositide binding Phox Homology domain of uncharacterized proteins containing PX and RUN domains; The PX domain is a phosphoinositide (PI) binding module involved in targeting proteins to PI-enriched membranes. Members in this subfamily are uncharacterized proteins containing an N-terminal RUN domain and a C-terminal PX domain. PX domain harboring proteins have been implicated in highly diverse functions such as cell signaling, vesicular trafficking, protein sorting, lipid modification, cell polarity and division, activation of T and B cells, and cell survival. In addition to protein-lipid interaction, the PX domain may also be involved in protein-protein interaction. The RUN domain is found in GTPases in the Rap and Rab families and may play a role in Ras-like signaling pathways.

Pssm-ID: 132810 Cd Length: 118 Bit Score: 41.18 E-value: 3.10e-04

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*..
gi 63055065  19 RVPNKHYVYIIRVT-----WSsgateaIYRRYSKFFDLQMQMLDKFP 60
Cdd:cd07277  13 KGSDAHHVYQVYIRirddeWN------VYRRYSEFYELHKKLKKKFP 53

Src homology 3 domain of DBL's Big Sister (DBS), a guanine nucleotide exchange factor; DBS, also called MCF2L (MCF2-transforming sequence-like protein) or OST, is a Rho GTPase guanine nucleotide exchange factor (RhoGEF), facilitating the exchange of GDP and GTP. It was originally isolated from a cDNA screen for sequences that cause malignant growth. It plays roles in regulating clathrin-mediated endocytosis and cell migration through its activation of Rac1 and Cdc42. Depending on cell type, DBS can also activate RhoA and RhoG. DBS contains a Sec14-like domain, spectrin-like repeats, a RhoGEF [or Dbl homology (DH)] domain, a Pleckstrin homology (PH) domain, and an 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.

Pssm-ID: 212791 Cd Length: 55 Bit Score: 39.58 E-value: 3.16e-04

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|...
gi 63055065 225 KYTVIYPYTARDQDEMNLERGAVVEVVQKNLEGWWKIR--YQGKEGWAPASYL 275
Cdd:cd11857   1 KYTVVADYEKGGPDDLTVKSGDLVQLIHEGDEGQWLVKnlSTRKEGWVPAANL 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.

Pssm-ID: 212883 [Multi-domain] Cd Length: 53 Bit Score: 39.42 E-value: 3.24e-04

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*.
gi 63055065 229 IYPYTARDQDEMNLERGAVVEVVQKNLEGWWKIRYQGKEGWAPASY 274
Cdd:cd11950   5 LYDFEALEDDELGFNSGDVIEVLDSSNPSWWKGRLHGKLGLFPANY 50

Bacterial SH3 domain;

Pssm-ID: 462405 [Multi-domain] Cd Length: 54 Bit Score: 39.15 E-value: 3.36e-04

                          10        20        30
                  ....*....|....*....|....*....|....*.
gi 63055065   242 LERGAVVEVVQKNLEGWWKIR-YQGKEGWAPASYLK 276
Cdd:pfam08239  19 LPKGEKVEVLEEQGGGWYKVRtYDGYEGWVSSSYLS 54

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.

Pssm-ID: 212706 [Multi-domain] Cd Length: 53 Bit Score: 39.21 E-value: 3.42e-04

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*..
gi 63055065 162 DYQKQESSEISLSVGQVVDIIEKNESGWWFVSTAEEQGWVPATCLEG 208
Cdd:cd11772   7 DYEAQHPDELSFEEGDLLYISDKSDPNWWKATCGGKTGLIPSNYVEE 53

First Src Homology 3 domain (SH3A) of Cbl-interacting protein of 85 kDa; CIN85, also called SH3 domain-containing kinase-binding protein 1 (SH3KBP1) or CD2-binding protein 3 (CD2BP3) or Ruk, is an adaptor protein that is involved in the downregulation of receptor tyrosine kinases by facilitating endocytosis through interaction with endophilin-associated ubiquitin ligase Cbl proteins. It is also important in many other cellular processes including vesicle-mediated transport, cytoskeletal remodelling, apoptosis, cell adhesion and migration, and viral infection, among others. CIN85 exists as multiple variants from alternative splicing; the main variant contains three SH3 domains, a proline-rich region, and a C-terminal coiled-coil domain. All of these domains enable CIN85 to bind various protein partners and assemble complexes that have been implicated in many different functions. This alignment model represents the first SH3 domain (SH3A) of CIN85; SH3A binds to internal proline-rich motifs within the proline-rich region. This intramolecular interaction serves as a regulatory mechanism to keep CIN85 in a closed conformation, preventing the recruitment of other proteins. SH3A has also been shown to bind ubiquitin and to an atypical PXXXPR motif at the C-terminus of Cbl and the cytoplasmic end of the cell adhesion protein CD2. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

Pssm-ID: 212985 [Multi-domain] Cd Length: 53 Bit Score: 39.11 E-value: 3.45e-04

                        10        20        30
                ....*....|....*....|....*....|...
gi 63055065 158 VVVADYQKQESSEISLSVGQVVDIIEKNESGWW 190
Cdd:cd12052   3 IVEFDYKAQHEDELTITVGDIITKIKKDDGGWW 35

Second Src homology 3 domain (or SH3B) of Intersectin-2; Intersectin-2 (ITSN2) is an adaptor protein that functions in exo- and endocytosis, actin cytoskeletal reorganization, and signal transduction. It plays a role in clathrin-coated pit (CCP) formation. It binds to many proteins through its multidomain structure and facilitate the assembly of multimeric complexes. ITSN2 also functions as a specific GEF for Cdc42 activation in epithelial morphogenesis, and is required in mitotic spindle orientation. It exists in alternatively spliced short and long isoforms. The short isoform contains two Eps15 homology domains (EH1 and EH2), a coiled-coil region and five SH3 domains (SH3A-E), while the long isoform, in addition, contains RhoGEF (also called Dbl-homologous or DH), Pleckstrin homology (PH) and C2 domains. The second SH3 domain (or SH3B) of ITSN2 is expected to bind protein partners, similar to ITSN1 which has been shown to bind WNK and CdGAP. 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.

Pssm-ID: 212923 [Multi-domain] Cd Length: 52 Bit Score: 39.25 E-value: 3.49e-04

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*
gi 63055065 232 YTARDQDEMNLERGAVVEVVQKNlEGWWKIRYQGKEGWAPASYLK 276
Cdd:cd11990   8 WTAKKDNHLNFSKNDIITVLEQQ-ENWWFGEVHGGRGWFPKSYVK 51

Fourth (C-terminal) Src homology 3 domain of Tyrosine kinase substrate with four SH3 domains; Tks4, also called SH3 and PX domain-containing protein 2B (SH3PXD2B) or HOFI, is a Src substrate and scaffolding protein that plays an important role in the formation of podosomes and invadopodia, the dynamic actin-rich structures that are related to cell migration and cancer cell invasion. It is required in the formation of functional podosomes, EGF-induced membrane ruffling, and lamellipodia generation. It plays an important role in cellular attachment and cell spreading. Tks4 is essential for the localization of MT1-MMP (membrane-type 1 matrix metalloproteinase) to invadopodia. It contains an N-terminal Phox homology (PX) domain and four SH3 domains. This model characterizes the fourth (C-terminal) SH3 domain of Tks4. 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.

Pssm-ID: 212951 Cd Length: 56 Bit Score: 39.49 E-value: 3.59e-04

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*.
gi 63055065 373 YYTIAEFQTTiPDGISFQAGLKVEVIEKSLSGWWYIQM----EDKEGWAPATFIDK 424
Cdd:cd12018   2 YVAVADFEGD-EDTSSFKEGTVFEVREKNSSGWWFCKVlsggPVWEGWIPSNYLRK 56

Src homology 3 domain of Myosins Ie, If, and similar proteins; Myosins Ie (MyoIe) and If (MyoIf) are nonmuscle, unconventional, long tailed, class I myosins containing an N-terminal motor domain and a myosin tail with TH1, TH2, and SH3 domains. MyoIe interacts with the endocytic proteins, dynamin and synaptojanin-1, through its SH3 domain; it may play a role in clathrin-dependent endocytosis. In the kidney, MyoIe is critical for podocyte function and normal glomerular filtration. Mutations in MyoIe is associated with focal segmental glomerulosclerosis, a disease characterized by massive proteinuria and progression to end-stage kidney disease. MyoIf is predominantly expressed in the immune system; it plays a role in immune cell motility and innate immunity. Mutations in MyoIf may be associated with the loss of hearing. The MyoIf gene has also been found to be fused to the MLL (Mixed lineage leukemia) gene in infant acute myeloid leukemias (AML). SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

Pssm-ID: 212761 [Multi-domain] Cd Length: 53 Bit Score: 38.93 E-value: 4.04e-04

                        10        20
                ....*....|....*....|....*....
gi 63055065 162 DYQKQESSEISLSVGQVVDIIEKNESGWW 190
Cdd:cd11827   7 AYDAQDTDELSFNEGDIIEILKEDPSGWW 35

Third Src Homology 3 domain of SH3 domain containing ring finger 1, an E3 ubiquitin-protein ligase; SH3RF1 is also called POSH (Plenty of SH3s) or SH3MD2 (SH3 multiple domains protein 2). It is a scaffold protein that acts as an E3 ubiquitin-protein ligase. It plays a role in calcium homeostasis through the control of the ubiquitin domain protein Herp. It may also have a role in regulating death receptor mediated and JNK mediated apoptosis. SH3RF1 also enhances the ubiquitination of ROMK1 potassium channel resulting in its increased endocytosis. It contains an N-terminal RING finger domain and four SH3 domains. This model represents the third SH3 domain, located in the middle, of SH3RF1. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

Pssm-ID: 212859 [Multi-domain] Cd Length: 55 Bit Score: 39.18 E-value: 4.19e-04

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|..
gi 63055065 226 YTVIYPYTARDQDEMNLERGAVVEVVQKNLEGWWK--IRYQGKEGWAPASYL 275
Cdd:cd11926   2 YVAIYPYTPRKEDELELRKGEMFLVFERCQDGWFKgtSMHTSKIGVFPGNYV 53

Src homology 3 domain of Cortactin and related proteins; This subfamily includes cortactin, Abp1 (actin-binding protein 1), hematopoietic lineage cell-specific protein 1 (HS1), and similar proteins. These proteins are involved in regulating actin dynamics through direct or indirect interaction with the Arp2/3 complex, which is required to initiate actin polymerization. They all contain at least one C-terminal SH3 domain. Cortactin and HS1 bind Arp2/3 and actin through an N-terminal region that contains an acidic domain and several copies of a repeat domain found in cortactin and HS1. Abp1 binds actin via an N-terminal actin-depolymerizing factor (ADF) homology domain. Yeast Abp1 binds Arp2/3 directly through two acidic domains. Mammalian Abp1 does not directly interact with Arp2/3; instead, it regulates actin dynamics indirectly by interacting with dynamin and WASP family proteins. The C-terminal region of these proteins acts as an adaptor or scaffold that can connect membrane trafficking and signaling proteins that bind the SH3 domain within the actin network. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

Pssm-ID: 212753 [Multi-domain] Cd Length: 54 Bit Score: 38.83 E-value: 4.45e-04

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|.
gi 63055065 158 VVVADYQKQESSEISLSVGQVVDIIEKNESGWWFVSTAEEQ-GWVPATCLE 207
Cdd:cd11819   3 KALYDYQAAEDNEISFVEGDIITQIEQIDEGWWLGVNAKGQkGLFPANYVE 53

N-terminal Src homology 3 domain of Growth factor receptor-bound protein 2; GRB2 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. It is ubiquitously expressed in all tissues throughout development and is important in cell cycle progression, motility, morphogenesis, and angiogenesis. In lymphocytes, GRB2 is associated with antigen receptor signaling components. GRB2 contains an N-terminal SH3 domain, a central SH2 domain, and a C-terminal SH3 domain. Its N-terminal SH3 domain 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.

Pssm-ID: 212879 [Multi-domain] Cd Length: 56 Bit Score: 38.85 E-value: 4.56e-04

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|
gi 63055065 230 YPYTARDQDEMNLERGAVVEVVqkNLE---GWWKIRYQGKEGWAPASYLK 276
Cdd:cd11946   7 YDFKATADDELSFKRGDILKVL--NEEcdqNWYKAELNGKDGFIPKNYIE 54

Fourth Src homology 3 domain (or SH3D) of Intersectin-2; Intersectin-2 (ITSN2) is an adaptor protein that functions in exo- and endocytosis, actin cytoskeletal reorganization, and signal transduction. It plays a role in clathrin-coated pit (CCP) formation. It binds to many proteins through its multidomain structure and facilitate the assembly of multimeric complexes. ITSN2 also functions as a specific GEF for Cdc42 activation in epithelial morphogenesis, and is required in mitotic spindle orientation. It exists in alternatively spliced short and long isoforms. The short isoform contains two Eps15 homology domains (EH1 and EH2), a coiled-coil region and five SH3 domains (SH3A-E), while the long isoform, in addition, contains RhoGEF (also called Dbl-homologous or DH), Pleckstrin homology (PH) and C2 domains. The fourth SH3 domain (or SH3D) of ITSN2 is expected to bind protein partners, similar to ITSN1 which has been shown to bind SHIP2, Numb, CdGAP, and N-WASP. 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.

Pssm-ID: 212927 Cd Length: 59 Bit Score: 39.14 E-value: 4.62e-04

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....
gi 63055065 159 VVADYQKQESSEISLSVGQVVDIIEKNESGWWF-----VSTAEEQGWVPATCLE 207
Cdd:cd11994   4 VTTAYVASGVEQLSLSPGQLILILKKNSSGWWLgelqaRGKKRQKGWFPASHVK 57

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.

Pssm-ID: 212881 [Multi-domain] Cd Length: 54 Bit Score: 39.03 E-value: 4.92e-04

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|...
gi 63055065 227 TVIYPYTARDQDEMNLERGAVVEVVqkNLE---GWWKIRYQGKEGWAPASYLK 276
Cdd:cd11948   3 VALYSFQATESDELPFQKGDILKIL--NMEddqNWYKAELQGREGYIPKNYIK 53

First 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.

Pssm-ID: 212707 [Multi-domain] Cd Length: 57 Bit Score: 38.94 E-value: 5.10e-04

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*
gi 63055065 157 YVVVADYQKQESSEISLSVGQVVDIIEKNESGWWFV-------STAEEQGWVPAT 204
Cdd:cd11773   2 YKALYDYEPQTEDELTIQEDDILYLLEKSDDDWWKVklkvnssDDDEPVGLVPAT 56

Src homology 3 domain of APC-Stimulated guanine nucleotide Exchange Factor; ASEF, also called ARHGEF4, exists in an autoinhibited form and is activated upon binding of the tumor suppressor APC (adenomatous polyposis coli). GEFs activate small GTPases by exchanging bound GDP for free GTP. ASEF can activate Rac1 or Cdc42. Truncated ASEF, which is found in colorectal cancers, is constitutively active and has been shown to promote angiogenesis and cancer cell migration. ASEF contains a SH3 domain followed by RhoGEF (also called Dbl-homologous or DH) and Pleckstrin Homology (PH) domains. In its autoinhibited form, the SH3 domain of ASEF forms an extensive interface with the DH and PH domains, blocking the Rac 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.

Pssm-ID: 212906 [Multi-domain] Cd Length: 73 Bit Score: 39.62 E-value: 5.10e-04

                        10        20        30
                ....*....|....*....|....*....|....*.
gi 63055065 387 ISFQAGLKVEVIEKSLSGWWYIQMEDKEGWAPATFI 422
Cdd:cd11973  34 LGFKAGDVIEVMDATNKEWWWGRVLDSEGWFPASFV 69

Second C-terminal Src homology 3 domain of Dynamin Binding Protein, also called Tuba, and similar domains; DNMBP or Tuba is a cdc42-specific guanine nucleotide exchange factor (GEF) that contains four N-terminal SH3 domains, a central RhoGEF [or Dbl homology (DH)] domain followed by a Bin/Amphiphysin/Rvs (BAR) domain, and two C-terminal SH3 domains. It provides a functional link between dynamin, Rho GTPase signaling, and actin dynamics. It plays an important role in regulating cell junction configuration. The C-terminal SH3 domains of DNMBP bind to N-WASP and Ena/VASP proteins, which are key regulatory proteins of the actin cytoskeleton. 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.

Pssm-ID: 213017 [Multi-domain] Cd Length: 57 Bit Score: 39.02 E-value: 5.18e-04

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*.
gi 63055065 226 YTVIYPYTARDQDEMNLERGAVVEVVQ-KNLEG---WWKIRYQGKEGWAPASYLKK 277
Cdd:cd12141   2 YYAVYTFKARSPNELSVSANQRVRILEfSDLTGnkeWWLAEANGQKGYVPSNYIRK 57

Third (or C-terminal) Src Homology 3 domain of Sorbin and SH3 domain containing 1 (Sorbs1), also called ponsin; Sorbs1 is also called ponsin, SH3P12, or CAP (c-Cbl associated protein). It is an adaptor protein containing one sorbin homology (SoHo) and three SH3 domains. It binds Cbl and plays a major role in regulating the insulin signaling pathway by enhancing insulin-induced phosphorylation of Cbl. Sorbs1, like vinexin, localizes at cell-ECM and cell-cell adhesion sites where it binds vinculin, paxillin, and afadin. It may function in the control of cell motility. Other interaction partners of Sorbs1 include c-Abl, Sos, flotillin, Grb4, ataxin-7, filamin C, among others. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

Pssm-ID: 212849 [Multi-domain] Cd Length: 59 Bit Score: 38.82 E-value: 5.40e-04

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|...
gi 63055065 226 YTVIYPYTARDQDEMNLERGAVVEVVQKNLEGWW--KIRYQGKEGWAPASYLK 276
Cdd:cd11916   4 YQALYSYAPQNDDELELRDGDIVDVMEKCDDGWFvgTSRRTKQFGTFPGNYVK 56

Src homology 3 domain of Growth Arrest Specific protein 7; GAS7 is mainly expressed in the brain and is required for neurite outgrowth. It may also play a role in the protection and migration of embryonic stem cells. Treatment-related acute myeloid leukemia (AML) has been reported resulting from mixed-lineage leukemia (MLL)-GAS7 translocations as a complication of primary cancer treatment. GAS7 contains an N-terminal SH3 domain, followed by a WW domain, and a central F-BAR 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.

Pssm-ID: 212763 [Multi-domain] Cd Length: 52 Bit Score: 38.65 E-value: 5.46e-04

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*...
gi 63055065 229 IYPYTA-RDQDEMNLERGAVVEVVQKNLEGWWKIRYQGKEGWAPASYL 275
Cdd:cd11829   5 LYAFTGeQHQQGLSFEAGELIRVLQAPDGGWWEGEKDGLRGWFPASYV 52

Src homology 3 domain of APC-Stimulated guanine nucleotide Exchange Factor 2; ASEF2, also called Spermatogenesis-associated protein 13 (SPATA13), is a GEF that localizes with actin at the leading edge of cells and is important in cell migration and adhesion dynamics. GEFs activate small GTPases by exchanging bound GDP for free GTP. ASEF2 can activate both Rac 1 and Cdc42, but only Rac1 activation is necessary for increased cell migration and adhesion turnover. Together with APC (adenomatous polyposis coli) and Neurabin2, a scaffold protein that binds F-actin, it is involved in regulating HGF-induced cell migration. ASEF2 contains a SH3 domain followed by RhoGEF (also called Dbl-homologous or DH) and Pleckstrin Homology (PH) domains. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

Pssm-ID: 212907 Cd Length: 54 Bit Score: 38.89 E-value: 5.56e-04

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*...
gi 63055065 229 IYPYTARDQDEMNLERGAVVEVVQKNLEGWWKIRYQGKEGWAPASYLK 276
Cdd:cd11974   6 LWDHVTMDDQELAFKAGDVIRVLEASNKDWWWGRNEDREAWFPASFVR 53

Src homology 3 domain of Yes Protein Tyrosine Kinase; Yes (or c-Yes) is a member of the Src subfamily of proteins, which are cytoplasmic (or non-receptor) PTKs. c-Yes kinase is the cellular homolog of the oncogenic protein (v-Yes) encoded by the Yamaguchi 73 and Esh sarcoma viruses. It displays functional overlap with other Src subfamily members, particularly Src. It also shows some unique functions such as binding to occludins, transmembrane proteins that regulate extracellular interactions in tight junctions. Yes also associates with a number of proteins in different cell types that Src does not interact with, like JAK2 and gp130 in pre-adipocytes, and Pyk2 in treated pulmonary vein endothelial cells. Although the biological function of Yes remains unclear, it appears to have a role in regulating cell-cell interactions and vesicle trafficking in polarized cells. Src kinases 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). 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.

Pssm-ID: 212940 [Multi-domain] Cd Length: 58 Bit Score: 38.86 E-value: 5.58e-04

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|...
gi 63055065 226 YTVIYPYTARDQDEMNLERGAVVEVVQkNLEG-WWKIRY--QGKEGWAPASYL 275
Cdd:cd12007   3 FVALYDYEARTTEDLSFKKGERFQIIN-NTEGdWWEARSiaTGKNGYIPSNYV 54

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.

Pssm-ID: 212850 [Multi-domain] Cd Length: 61 Bit Score: 38.82 E-value: 5.73e-04

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*.
gi 63055065 224 EKYTVIYPYTARDQDEMNLERGAVVEVVQKNLEGWW--KIRYQGKEGWAPASYLKK 277
Cdd:cd11917   5 EPFQALYNYMPRNEDELELREGDVIDVMEKCDDGWFvgTSRRTKFFGTFPGNYVKR 60

Fourth Src homology 3 domain (or SH3D) of Intersectin-1; Intersectin-1 (ITSN1) is an adaptor protein that functions in exo- and endocytosis, actin cytoskeletal reorganization, and signal transduction. It plays a role in clathrin-coated pit (CCP) formation. It binds to many proteins through its multidomain structure and facilitate the assembly of multimeric complexes. ITSN1 localizes in membranous organelles, CCPs, the Golgi complex, and may be involved in the cell membrane trafficking system. It exists in alternatively spliced short and long isoforms. The short isoform contains two Eps15 homology domains (EH1 and EH2), a coiled-coil region and five SH3 domains (SH3A-E), while the long isoform, in addition, contains RhoGEF (also called Dbl-homologous or DH), Pleckstrin homology (PH) and C2 domains. The fourth SH3 domain (or SH3D) of ITSN1 has been shown to bind SHIP2, Numb, CdGAP, and N-WASP. 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.

Pssm-ID: 212926 Cd Length: 65 Bit Score: 38.95 E-value: 5.87e-04

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|.
gi 63055065 221 EEEEKYTVIYPYTARDQDEMNLERGAVVEVVQKNLEGWW--KIRYQGKE---GWAPASYLK 276
Cdd:cd11993   1 KKPEIAQVIASYTATGPEQLTLAPGQLILIRKKNPGGWWegELQARGKKrqiGWFPANYVK 61

N-terminal Src Homology 3 domain of Ct10 Regulator of Kinase adaptor proteins; CRK adaptor proteins consists of SH2 and SH3 domains, which bind tyrosine-phosphorylated peptides and proline-rich motifs, respectively. They function downstream of protein tyrosine kinases in many signaling pathways started by various extracellular signals, including growth and differentiation factors. Cellular CRK (c-CRK) contains a single SH2 domain, followed by N-terminal and C-terminal SH3 domains. It is involved in the regulation of many cellular processes including cell growth, motility, adhesion, and apoptosis. CRK has been implicated in the malignancy of various human cancers. The N-terminal SH3 domain of CRK binds a number of target proteins including DOCK180, C3G, SOS, and cABL. The CRK family includes two alternatively spliced protein forms, CRKI and CRKII, that are expressed by the CRK gene, and the CRK-like (CRKL) protein, which is expressed by a distinct gene (CRKL). 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.

Pssm-ID: 212692 [Multi-domain] Cd Length: 55 Bit Score: 38.50 E-value: 6.73e-04

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*
gi 63055065 224 EKYTVIYPYTARDQDEMNLERGAVVEVVQKNLEGWWKIR-YQGKEGWAPASYLKK 277
Cdd:cd11758   1 EYVRALFDFPGNDDEDLPFKKGEILTVIRKPEEQWWNARnSEGKTGMIPVPYVEK 55

Src homology 3 domain of Hematopoietic lineage cell-specific protein 1; HS1, also called HCLS1 (hematopoietic cell-specific Lyn substrate 1), is a cortactin homolog expressed specifically in hematopoietic cells. It is an actin regulatory protein that binds the Arp2/3 complex and stabilizes branched actin filaments. It is required for cell spreading and signaling in lymphocytes. It regulates cytoskeletal remodeling that controls lymphocyte trafficking, and it also affects tissue invasion and infiltration of leukemic B cells. Like cortactin, HS1 contains an N-terminal acidic domain, several copies of a repeat domain found in cortactin and HS1, a proline-rich region, and a C-terminal SH3 domain. The N-terminal region binds the Arp2/3 complex and F-actin, while the C-terminal region acts as an adaptor or scaffold that can connect varied proteins that bind the SH3 domain within the actin network. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

Pssm-ID: 213006 [Multi-domain] Cd Length: 55 Bit Score: 38.66 E-value: 6.83e-04

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*...
gi 63055065 229 IYPYTARDQDEMNLERGAVVEVVQKNLEGWWKIRYQGKEGWAPASYLK 276
Cdd:cd12073   6 LYDYQGEGDDEISFDPQETITDIEMVDEGWWKGTCHGHRGLFPANYVE 53

Src homology 3 domain of Cortactin; Cortactin was originally identified as a substrate of Src kinase. It is an actin regulatory protein that binds to the Arp2/3 complex and stabilizes branched actin filaments. It is involved in cellular processes that affect cell motility, adhesion, migration, endocytosis, and invasion. It is expressed ubiquitously except in hematopoietic cells, where the homolog hematopoietic lineage cell-specific 1 (HS1) is expressed instead. Cortactin contains an N-terminal acidic domain, several copies of a repeat domain found in cortactin and HS1, a proline-rich region, and a C-terminal SH3 domain. The N-terminal region interacts with the Arp2/3 complex and F-actin, and is crucial in regulating branched actin assembly. Cortactin also serves as a scaffold and provides a bridge to the actin cytoskeleton for membrane trafficking and signaling proteins that bind to its SH3 domain. Binding partners for the SH3 domain of cortactin include dynamin2, N-WASp, MIM, FGD1, among others. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

Pssm-ID: 212892 [Multi-domain] Cd Length: 53 Bit Score: 38.17 E-value: 7.28e-04

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*...
gi 63055065 229 IYPYTARDQDEMNLERGAVVEVVQKNLEGWWKIRYQGKEGWAPASYLK 276
Cdd:cd11959   5 LYDYQAADDDEISFDPDDIITNIEMIDEGWWRGVCRGKYGLFPANYVE 52

First 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.

Pssm-ID: 212707 [Multi-domain] Cd Length: 57 Bit Score: 38.56 E-value: 7.33e-04

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*.
gi 63055065 226 YTVIYPYTARDQDEMNLERGAVVEVVQKNLEGWWKIRYQ-------GKEGWAPASY 274
Cdd:cd11773   2 YKALYDYEPQTEDELTIQEDDILYLLEKSDDDWWKVKLKvnssdddEPVGLVPATY 57

Src Homology 3 domain of Abelson helper integration site-1 (AHI-1); AHI-1, also called Jouberin, is expressed in high levels in the brain, gonad tissues, and skeletal muscle. It is an adaptor protein that interacts with the small GTPase Rab8a and regulates it distribution and function, affecting cilium formation and vesicle transport. Mutations in the AHI-1 gene can cause Joubert syndrome, a disorder characterized by brainstem malformations, cerebellar aplasia/hypoplasia, and retinal dystrophy. AHI-1 variation is also associated with susceptibility to schizophrenia and type 2 diabetes mellitus progression. AHI-1 contains WD40 and SH3 domains. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

Pssm-ID: 212746 [Multi-domain] Cd Length: 52 Bit Score: 38.26 E-value: 7.56e-04

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*..
gi 63055065 158 VVVADYQKQESSEISLSVGQVVDIIEKNESGWWFVSTAE-EQGWVPA 203
Cdd:cd11812   3 VALYDYTANRSDELTIHRGDIIRVLYKDNDNWWFGSLVNgQQGYFPA 49

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.

Pssm-ID: 212866 [Multi-domain] Cd Length: 58 Bit Score: 38.45 E-value: 7.57e-04

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|...
gi 63055065 226 YTVIYPYTARDQDEMNLERGAVVEVVQKNLEGWW--KIRYQGKEGWAPASYLK 276
Cdd:cd11933   4 FRAMYDYRAADDDEVSFKDGDTIVNVQTIDEGWMygTVQRTGKTGMLPANYVE 56

The phosphoinositide binding Phox Homology domain of yeast MDM1p; The PX domain is a phosphoinositide binding (PI) module present in many proteins with diverse functions such as cell signaling, vesicular trafficking, protein sorting, and lipid modification, among others. Yeast MDM1p is a filament-like protein localized in punctate structures distributed throughout the cytoplasm. It plays an important role in nuclear and mitochondrial transmission to daughter buds. Members of this subfamily show similar domain architectures as some sorting nexins (SNXs). Some members are similar to SNX19 in that they contain an N-terminal PXA domain, a central PX domain, and a C-terminal domain that is conserved in some SNXs. Others are similar to SNX13 and SNX14, which also harbor these three domains as well as a regulator of G protein signaling (RGS) domain in between the PXA and PX domains. SNXs make up the largest group among PX domain containing proteins. They are involved in regulating membrane traffic and protein sorting in the endosomal system. The PX domain of SNXs binds PIs and targets the protein to PI-enriched membranes. SNXs differ from each other in PI-binding specificity and affinity, and the presence of other protein-protein interaction domains, which help determine subcellular localization and specific function in the endocytic pathway.

Pssm-ID: 132786 Cd Length: 133 Bit Score: 40.37 E-value: 8.26e-04

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 63055065  26 VYIIRVTWSSG----ATEAIYRRYSKFFDLQMQMLDKFPMEGGQKDPKQRIIPFLPGKilfrrshiRDVAVKRLIPIDEY 101
Cdd:cd06876  40 VYLIEVQRLNNddqsSGWVVARRYSEFLELHKYLKKRYPGVLKLDFPQKRKISLKYSK--------TLLVEERRKALEKY 111


                ....*...
gi 63055065 102 CKALIQLP 109
Cdd:cd06876 112 LQELLKIP 119

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.

Pssm-ID: 212760 [Multi-domain] Cd Length: 52 Bit Score: 38.07 E-value: 8.37e-04

                        10        20        30
                ....*....|....*....|....*....|....
gi 63055065 159 VVA--DYQKQESSEISLSVGQVVDIIEKNESGWW 190
Cdd:cd11826   2 VVAlyDYTADKDDELSFQEGDIIYVTKKNDDGWY 35

Src homology 3 domain of Abl Interactor 2; Abi2 is highly expressed in the brain and eye. It regulates actin cytoskeletal reorganization at adherens junctions and dendritic spines, which is important in cell morphogenesis, migration, and cognitive function. Mice deficient with Abi2 show defects in orientation and migration of lens fibers, neuronal migration, dendritic spine morphology, as well as deficits in learning and memory. 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. 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.

Pssm-ID: 212905 [Multi-domain] Cd Length: 61 Bit Score: 38.45 E-value: 9.26e-04

                        10        20        30
                ....*....|....*....|....*....|....*..
gi 63055065 154 LEQYVVVADYQKQESSEISLSVGQVVDIIEKNESGWW 190
Cdd:cd11972   2 LEKVVAIYDYTKDKEDELSFQEGAIIYVIKKNDDGWY 38

Src homology 3 domain of ARHGEF9-like Rho guanine nucleotide exchange factors; Members of this family contain a SH3 domain followed by RhoGEF (also called Dbl-homologous or DH) and Pleckstrin Homology (PH) domains. They include the Rho guanine nucleotide exchange factors ARHGEF9, ASEF (also called ARHGEF4), ASEF2, and similar proteins. GEFs activate small GTPases by exchanging bound GDP for free GTP. ARHGEF9 specifically activates Cdc42, while both ASEF and ASEF2 can activate Rac1 and Cdc42. ARHGEF9 is highly expressed in the brain and it interacts with gephyrin, a postsynaptic protein associated with GABA and glycine receptors. ASEF plays a role in angiogenesis and cell migration. ASEF2 is important in cell migration and adhesion dynamics. ASEF exists in an autoinhibited form and is activated upon binding of the tumor suppressor APC (adenomatous polyposis coli), leading to the activation of Rac1 or Cdc42. In its autoinhibited form, the SH3 domain of ASEF forms an extensive interface with the DH and PH domains, blocking the Rac 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.

Pssm-ID: 212762 [Multi-domain] Cd Length: 53 Bit Score: 38.13 E-value: 9.27e-04

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*
gi 63055065 232 YTARDQDEMNLERGAVVEVVQKNLEGWWKIRYQGKEGWAPASYLK 276
Cdd:cd11828   8 HVTMDPEELGFKAGDVIEVLDMSDKDWWWGSIRDEEGWFPASFVR 52

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.

Pssm-ID: 212714 [Multi-domain] Cd Length: 55 Bit Score: 38.05 E-value: 9.62e-04

                        10        20        30        40
                ....*....|....*....|....*....|....*....|...
gi 63055065 157 YVVVADYQKQESSEISLSVGQVVDIIEKNESGwWFVSTAEEQG 199
Cdd:cd11780   2 YRALYSYTPQNEDELELREGDIVYVMEKCDDG-WFVGTSERTG 43

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.

Pssm-ID: 212779 [Multi-domain] Cd Length: 52 Bit Score: 37.95 E-value: 1.03e-03

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|..
gi 63055065 156 QYVVVADYQKQESSEISLSVGQVVDIIEKNESGWWFV---STAEEqGWVPAT 204
Cdd:cd11845   1 IYVALYDYEARTDDDLSFKKGDRLQILDDSDGDWWLArhlSTGKE-GYIPSN 51

Src homology 3 domain of Lyn Protein Tyrosine Kinase; Lyn is a member of the Src subfamily of proteins, which are cytoplasmic (or non-receptor) PTKs. Lyn is expressed in B lymphocytes and myeloid cells. It exhibits both positive and negative regulatory roles in B cell receptor (BCR) signaling. Lyn, as well as Fyn and Blk, promotes B cell activation by phosphorylating ITAMs (immunoreceptor tyr activation motifs) in CD19 and in Ig components of BCR. It negatively regulates signaling by its unique ability to phosphorylate ITIMs (immunoreceptor tyr inhibition motifs) in cell surface receptors like CD22 and CD5. Lyn also plays an important role in G-CSF receptor signaling by phosphorylating a variety of adaptor molecules. Src kinases 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). 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.

Pssm-ID: 212937 [Multi-domain] Cd Length: 56 Bit Score: 38.05 E-value: 1.06e-03

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|.
gi 63055065 229 IYPYTARDQDEMNLERGAVVEVVQKNLEgWWKIR--YQGKEGWAPASYLKK 277
Cdd:cd12004   5 LYPYDGIHEDDLSFKKGEKLKVIEEHGE-WWKARslTTKKEGFIPSNYVAK 54

First C-terminal Src homology 3 domain of SH3 and cysteine-rich domain-containing protein 3 (Stac3); Stac proteins are putative adaptor proteins that contain a cysteine-rich C1 domain and one or two SH3 domains at the C-terminus. There are three mammalian members (Stac1, Stac2, and Stac3) of this family. Stac1 and Stac3 contain two SH3 domains while Stac2 contains a single SH3 domain at the C-terminus. Stac1 and Stac2 have been found to be expressed differently in mature dorsal root ganglia (DRG) neurons. Stac1 is mainly expressed in peptidergic neurons while Stac2 is found in a subset of nonpeptidergic and all trkB+ neurons. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

Pssm-ID: 212919 [Multi-domain] Cd Length: 53 Bit Score: 37.97 E-value: 1.16e-03

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|
gi 63055065 373 YYTIAEFQTTIPDGISFQAGLKVEVIEKSLSGWWYIQMEDKEGWAPATFI 422
Cdd:cd11986   2 FVALYRFKALEKDDLDFHPGERITVIDDSNEEWWRGKIGEKTGYFPMNFI 51

Src homology 3 domain of Fyn and Yrk Protein Tyrosine Kinases; Fyn and Yrk (Yes-related kinase) are members of the Src subfamily of proteins, which are cytoplasmic (or non-receptor) PTKs. Fyn, together with Lck, plays a critical role in T-cell signal transduction by phosphorylating ITAM (immunoreceptor tyr activation motif) sequences on T-cell receptors, ultimately leading to the proliferation and differentiation of T-cells. In addition, Fyn is involved in the myelination of neurons, and is implicated in Alzheimer's and Parkinson's diseases. Yrk has been detected only in chickens. It is primarily found in neuronal and epithelial cells and in macrophages. It may play a role in inflammation and in response to injury. Src kinases 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). 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.

Pssm-ID: 212939 [Multi-domain] Cd Length: 56 Bit Score: 37.72 E-value: 1.20e-03

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|..
gi 63055065 226 YTVIYPYTARDQDEMNLERGAVVEVVQKNLEGWWKIR--YQGKEGWAPASYL 275
Cdd:cd12006   3 FVALYDYEARTEDDLSFHKGEKFQILNSSEGDWWEARslTTGETGYIPSNYV 54

Src Homology 3 domain of Sorting Nexin 9 and similar proteins; Sorting nexins (SNXs) are Phox homology (PX) domain containing proteins that are involved in regulating membrane traffic and protein sorting in the endosomal system. SNXs differ from each other in their lipid-binding specificity, subcellular localization and specific function in the endocytic pathway. This subfamily consists of SH3 domain containing SNXs including SNX9, SNX18, SNX33, and similar proteins. SNX9 is localized to plasma membrane endocytic sites and acts primarily in clathrin-mediated endocytosis, while SNX18 is localized to peripheral endosomal structures, and acts in a trafficking pathway that is clathrin-independent but relies on AP-1 and PACS1. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

Pssm-ID: 212697 [Multi-domain] Cd Length: 55 Bit Score: 37.69 E-value: 1.23e-03

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....
gi 63055065 156 QYVVVADYQKQESSEISLSVGQVVDIIEKN-ESGWWF-VSTAEEQGWVPATCLE 207
Cdd:cd11763   1 KVRALYDFDSQPSGELSLRAGEVLTITRQDvGDGWLEgRNSRGEVGLFPSSYVE 54

The phosphoinositide binding Phox Homology domain of KIF16B kinesin or Sorting Nexin 23; The PX domain is a phosphoinositide (PI) binding module present in many proteins with diverse functions such as cell signaling, vesicular trafficking, protein sorting, and lipid modification, among others. KIF16B, also called sorting nexin 23 (SNX23), is a family-3 kinesin which harbors an N-terminal kinesin motor domain containing ATP and microtubule binding sites, a ForkHead Associated (FHA) domain, and a C-terminal PX domain. The PX domain of KIF16B binds to phosphatidylinositol-3-phosphate (PI3P) in early endosomes and plays a role in the transport of early endosomes to the plus end of microtubules. By regulating early endosome plus end motility, KIF16B modulates the balance between recycling and degradation of receptors. SNXs make up the largest group among PX domain containing proteins. They are involved in regulating membrane traffic and protein sorting in the endosomal system. The PX domain of SNXs binds PIs and targets the protein to PI-enriched membranes. SNXs differ from each other in PI-binding specificity and affinity, and the presence of other protein-protein interaction domains, which help determine subcellular localization and specific function in the endocytic pathway.

Pssm-ID: 132784 Cd Length: 127 Bit Score: 39.67 E-value: 1.26e-03

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 63055065  24 HYVYIIRVTwSSGATEAIYRRYSKFFDLQMQMLDKFPMEGGqkdpkqriIPFLPGKILFRRShiRDVAVKRLIPIDEYCK 103
Cdd:cd06874  18 HFEFEVKIT-VLDETWTVFRRYSRFRELHKTMKLKYPEVAA--------LEFPPKKLFGNKS--ERVAKERRRQLETYLR 86

                        90
                ....*....|..
gi 63055065 104 ALIQLPPYISQC 115
Cdd:cd06874  87 NFFSVCLKLPAC 98

Src homology 3 domain of APC-Stimulated guanine nucleotide Exchange Factor; ASEF, also called ARHGEF4, exists in an autoinhibited form and is activated upon binding of the tumor suppressor APC (adenomatous polyposis coli). GEFs activate small GTPases by exchanging bound GDP for free GTP. ASEF can activate Rac1 or Cdc42. Truncated ASEF, which is found in colorectal cancers, is constitutively active and has been shown to promote angiogenesis and cancer cell migration. ASEF contains a SH3 domain followed by RhoGEF (also called Dbl-homologous or DH) and Pleckstrin Homology (PH) domains. In its autoinhibited form, the SH3 domain of ASEF forms an extensive interface with the DH and PH domains, blocking the Rac 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.

Pssm-ID: 212906 [Multi-domain] Cd Length: 73 Bit Score: 38.46 E-value: 1.27e-03

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*...
gi 63055065 229 IYPYTARDQDEMNLERGAVVEVVQKNLEGWWKIRYQGKEGWAPASYLK 276
Cdd:cd11973  23 LWDHVTMDDQELGFKAGDVIEVMDATNKEWWWGRVLDSEGWFPASFVR 70

Src Homology 3 domain of Epidermal growth factor receptor kinase substrate 8 and similar proteins; This group is composed of Eps8 and Eps8-like proteins including Eps8-like 1-3, among others. These proteins contain N-terminal Phosphotyrosine-binding (PTB), central SH3, and C-terminal effector domains. Eps8 binds either Abi1 (also called E3b1) or Rab5 GTPase activating protein RN-tre through its SH3 domain. With Abi1 and Sos1, it becomes part of a trimeric complex that is required to activate Rac. Together with RN-tre, it inhibits the internalization of EGFR. The SH3 domains of Eps8 and similar proteins recognize peptides containing a PxxDY motif, instead of the classical PxxP motif. SH3 domains are protein interaction domains that usually 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.

Pssm-ID: 212698 [Multi-domain] Cd Length: 54 Bit Score: 37.63 E-value: 1.36e-03

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*..
gi 63055065 226 YTVIYPYTARDQDEMNLERGAVVEVVQKNLEgWWKIR-YQGKEGWAP 271
Cdd:cd11764   2 VRVLYDFTARNSKELSVLKGEYLEVLDDSRQ-WWKVRnSRGQVGYVP 47

Src homology 3 domain of Myosins Ie, If, and similar proteins; Myosins Ie (MyoIe) and If (MyoIf) are nonmuscle, unconventional, long tailed, class I myosins containing an N-terminal motor domain and a myosin tail with TH1, TH2, and SH3 domains. MyoIe interacts with the endocytic proteins, dynamin and synaptojanin-1, through its SH3 domain; it may play a role in clathrin-dependent endocytosis. In the kidney, MyoIe is critical for podocyte function and normal glomerular filtration. Mutations in MyoIe is associated with focal segmental glomerulosclerosis, a disease characterized by massive proteinuria and progression to end-stage kidney disease. MyoIf is predominantly expressed in the immune system; it plays a role in immune cell motility and innate immunity. Mutations in MyoIf may be associated with the loss of hearing. The MyoIf gene has also been found to be fused to the MLL (Mixed lineage leukemia) gene in infant acute myeloid leukemias (AML). SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

Pssm-ID: 212761 [Multi-domain] Cd Length: 53 Bit Score: 37.39 E-value: 1.41e-03

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*..
gi 63055065 860 GDEDTSSFQEGTVFEVREKNSSGWWFCQvLSGApswEGWIPSNYLRK 906
Cdd:cd11827  11 QDTDELSFNEGDIIEILKEDPSGWWTGR-LRGK---EGLFPGNYVEK 53

Src homology 3 domain of Myosins Ie, If, and similar proteins; Myosins Ie (MyoIe) and If (MyoIf) are nonmuscle, unconventional, long tailed, class I myosins containing an N-terminal motor domain and a myosin tail with TH1, TH2, and SH3 domains. MyoIe interacts with the endocytic proteins, dynamin and synaptojanin-1, through its SH3 domain; it may play a role in clathrin-dependent endocytosis. In the kidney, MyoIe is critical for podocyte function and normal glomerular filtration. Mutations in MyoIe is associated with focal segmental glomerulosclerosis, a disease characterized by massive proteinuria and progression to end-stage kidney disease. MyoIf is predominantly expressed in the immune system; it plays a role in immune cell motility and innate immunity. Mutations in MyoIf may be associated with the loss of hearing. The MyoIf gene has also been found to be fused to the MLL (Mixed lineage leukemia) gene in infant acute myeloid leukemias (AML). SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

Pssm-ID: 212761 [Multi-domain] Cd Length: 53 Bit Score: 37.39 E-value: 1.47e-03

                        10        20        30        40
                ....*....|....*....|....*....|....*....|
gi 63055065 385 DGISFQAGLKVEVIEKSLSGWWYIQMEDKEGWAPATFIDK 424
Cdd:cd11827  14 DELSFNEGDIIEILKEDPSGWWTGRLRGKEGLFPGNYVEK 53

Fourth Src homology 3 domain of ADAM-binding protein Eve-1; Eve-1, also called SH3 domain-containing protein 19 (SH3D19) or EEN-binding protein (EBP), exists in multiple alternatively spliced isoforms. The longest isoform contains five SH3 domain in the C-terminal region and seven proline-rich motifs in the N-terminal region. It is abundantly expressed in skeletal muscle and heart, and may be involved in regulating the activity of ADAMs (A disintegrin and metalloproteases). Eve-1 interacts with EEN, an endophilin involved in endocytosis and may be the target of the MLL-EEN fusion protein that is implicated in leukemogenesis. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

Pssm-ID: 212751 [Multi-domain] Cd Length: 50 Bit Score: 37.07 E-value: 1.63e-03

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*.
gi 63055065 229 IYPYTARDQDEMNLERGAVVEVVQKNLEGWWKIRYQGKEGWAPASY 274
Cdd:cd11817   5 LYDFTGETEEDLSFQRGDRILVTEHLDAEWSRGRLNGREGIFPRAF 50

Src Homology 3 domain of Apoptosis Stimulating of p53 protein 1; ASPP1, like ASPP2, activates the apoptotic function of the p53 family of tumor suppressors (p53, p63, and p73). In addition, it functions in the cytoplasm to regulate the nuclear localization of the transcriptional cofactors YAP and TAZ by inihibiting their phosphorylation; YAP and TAZ are important regulators of cell expansion, differentiation, migration, and invasion. ASPP1 is downregulated in breast tumors expressing wild-type p53. It contains a proline-rich region, four ankyrin (ANK) repeats, and an SH3 domain at its C-terminal half. The SH3 domain and the ANK repeats of ASPP1 contribute to the p53 binding site; they bind to the DNA binding domain of p53. 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.

Pssm-ID: 212887 [Multi-domain] Cd Length: 57 Bit Score: 37.31 E-value: 1.66e-03

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*...
gi 63055065 162 DYQKQESSEISLSVGQVVDIIEK---NESGWWFVSTAEEQGWVPATCL 206
Cdd:cd11954   8 DYEAQNADELSFQEGDAITILRRkddSETEWWWARLNDKEGYVPKNLL 55

Src Homology 3 domain of Sdc25/Cdc25 guanine nucleotide exchange factors; This subfamily is composed of the Saccharomyces cerevisiae guanine nucleotide exchange factors (GEFs) Sdc25 and Cdc25, and similar proteins. These GEFs regulate Ras by stimulating the GDP/GTP exchange on Ras. Cdc25 is involved in the Ras/PKA pathway that plays an important role in the regulation of metabolism, stress responses, and proliferation, depending on available nutrients and conditions. Proteins in this subfamily contain an N-terminal SH3 domain as well as REM (Ras exchanger motif) and RasGEF domains at the C-terminus. SH3 domains bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs; they play a role in the regulation of enzymes by intramolecular interactions, changing the subcellular localization of signal pathway components and mediate multiprotein complex assemblies.

Pssm-ID: 212816 Cd Length: 55 Bit Score: 37.26 E-value: 1.74e-03

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|..
gi 63055065 228 VIYPYTARDQDEMNLERGAVVEVVQKNLEGWW-----KIRYQGKEGWAPASY 274
Cdd:cd11883   4 ALYDFTPKSKNQLSFKAGDIIYVLNKDPSGWWdgviiSSSGKVKRGWFPSNY 55

Second C-terminal Src homology 3 domain of Dynamin Binding Protein, also called Tuba, and similar domains; DNMBP or Tuba is a cdc42-specific guanine nucleotide exchange factor (GEF) that contains four N-terminal SH3 domains, a central RhoGEF [or Dbl homology (DH)] domain followed by a Bin/Amphiphysin/Rvs (BAR) domain, and two C-terminal SH3 domains. It provides a functional link between dynamin, Rho GTPase signaling, and actin dynamics. It plays an important role in regulating cell junction configuration. The C-terminal SH3 domains of DNMBP bind to N-WASP and Ena/VASP proteins, which are key regulatory proteins of the actin cytoskeleton. Also included in this subfamily is the second C-terminal SH3 domain of Rho guanine nucleotide exchange factor 37 (ARHGEF37), whose function is still unknown. 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.

Pssm-ID: 212734 [Multi-domain] Cd Length: 57 Bit Score: 37.35 E-value: 1.83e-03

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|
gi 63055065 852 YVAVANFEG-DEDTSSFQEGTVFEVRE----KNSSGWWFCQVLSGapswEGWIPSNYLRK 906
Cdd:cd11800   2 YYALYTFEArSPGELSVTEGQVVTVLEkhdlKGNPEWWLVEDRGK----QGYVPSNYLAK 57

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.

Pssm-ID: 212757 [Multi-domain] Cd Length: 53 Bit Score: 37.32 E-value: 1.86e-03

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*....
gi 63055065 375 TIAEFQTTIPDGISFQAGLKVEVIEKSLSGWWYIQMEDKEGWAPATFID 423
Cdd:cd11823   4 ALYSYTANREDELSLQPGDIIEVHEKQDDGWWLGELNGKKGIFPATYVE 52

Src Homology 3 domain of Class A Dedicator of Cytokinesis proteins 1 and 5; Dock1, also called Dock180, and Dock5 are class A DOCKs and are atypical guanine nucleotide exchange factors (GEFs) that lack the conventional Dbl homology (DH) domain. Dock1 interacts with the scaffold protein Elmo and the resulting complex functions upstream of Rac in many biological events including phagocytosis of apoptotic cells, cell migration and invasion. Dock5 functions upstream of Rac1 to regulate osteoclast function. All DOCKs contain two homology domains: the DHR-1 (Dock homology region-1), also called CZH1 (CED-5, Dock180, and MBC-zizimin homology 1), and DHR-2 (also called CZH2 or Docker). The DHR-1 domain binds phosphatidylinositol-3,4,5-triphosphate while DHR-2 contains the catalytic activity for Rac and/or Cdc42. Class A DOCKs also contain an SH3 domain at the N-terminal region and a PxxP motif at the C-terminus; they are specific GEFs for Rac. The SH3 domain of Dock1 binds to DHR-2 in an autoinhibitory manner; binding of Elmo to the SH3 domain of Dock1 exposes the DHR-2 domain and promotes GEF 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.

Pssm-ID: 212984 [Multi-domain] Cd Length: 56 Bit Score: 37.11 E-value: 1.88e-03

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|
gi 63055065 229 IYPYTARDQDEMNLERGAVVEVVQkNLEGWWK---IRYQGKEGWAPASYL 275
Cdd:cd12051   5 IYNYDARGPDELSLQIGDTVHILE-TYEGWYRgytLRKKSKKGIFPASYI 53

Src homology 3 domain of SH3 and multiple ankyrin repeat domains protein 3; Shank3, also called ProSAP2 (Proline-rich synapse-associated protein 2), is widely expressed. It plays a role in the formation of dendritic spines and synapses. Haploinsufficiency of the Shank3 gene causes the 22q13 deletion/Phelan-McDermid syndrome, and variants of Shank3 have been implicated in autism spectrum disorder, schizophrenia, and intellectual disability. Shank proteins carry scaffolding functions through multiple sites of protein-protein interaction in its domain architecture, including ankyrin (ANK) repeats, a long proline rich region, as well as SH3, PDZ, and SAM domains. The SH3 domain of Shank binds GRIP, a scaffold protein that binds AMPA receptors and Eph receptors/ligands. 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.

Pssm-ID: 212917 Cd Length: 52 Bit Score: 37.24 E-value: 1.98e-03

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*...
gi 63055065 225 KYTVIYPYTARDQDEMNLERGAVVEVVQKNLEGWWKIRYQGKEGWAPA 272
Cdd:cd11984   2 TFIAVKAYSPQGEGEIQLNRGERVKVLSIGEGGFWEGTVKGRTGWFPA 49

The phosphoinositide binding Phox Homology domain of the fungal protein YPT35; The PX domain is a phosphoinositide (PI) binding module present in many proteins with diverse functions such as cell signaling, vesicular trafficking, protein sorting, and lipid modification, among others. This subfamily is composed of YPT35 proteins from the fungal subkingdom Dikarya. The PX domain is involved in targeting of proteins to PI-enriched membranes, and may also be involved in protein-protein interaction. The PX domain of YPT35 binds to phosphatidylinositol 3-phosphate (PI3P). It also serves as a protein interaction domain, binding to members of the Yip1p protein family, which localize to the ER and Golgi. YPT35 is mainly associated with endosomes and together with Yip1p proteins, may be involved in a specific function in the endocytic pathway.

Pssm-ID: 132813 Cd Length: 120 Bit Score: 38.85 E-value: 1.99e-03

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 63055065   7 IVEVKVLD---VQKRRVPNKHYVYIIRVT--WSSGATEAIYRRYSKFFDLQMQMLDKFPmeggqkDPKQRIIPFLPGKIL 81
Cdd:cd07280   2 ATDVNVGDytiVGGDTGGGAYVVWKITIEtkDLIGSSIVAYKRYSEFVQLREALLDEFP------RHKRNEIPQLPPKVP 75


                ....*..
gi 63055065  82 FRRSHIR 88
Cdd:cd07280  76 WYDSRVN 82

Src homology 3 domain of Cortactin and related proteins; This subfamily includes cortactin, Abp1 (actin-binding protein 1), hematopoietic lineage cell-specific protein 1 (HS1), and similar proteins. These proteins are involved in regulating actin dynamics through direct or indirect interaction with the Arp2/3 complex, which is required to initiate actin polymerization. They all contain at least one C-terminal SH3 domain. Cortactin and HS1 bind Arp2/3 and actin through an N-terminal region that contains an acidic domain and several copies of a repeat domain found in cortactin and HS1. Abp1 binds actin via an N-terminal actin-depolymerizing factor (ADF) homology domain. Yeast Abp1 binds Arp2/3 directly through two acidic domains. Mammalian Abp1 does not directly interact with Arp2/3; instead, it regulates actin dynamics indirectly by interacting with dynamin and WASP family proteins. The C-terminal region of these proteins acts as an adaptor or scaffold that can connect membrane trafficking and signaling proteins that bind the SH3 domain within the actin network. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

Pssm-ID: 212753 [Multi-domain] Cd Length: 54 Bit Score: 37.29 E-value: 2.01e-03

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|.
gi 63055065 227 TVIYPYTARDQDEMNLERGAVVEVVQKNLEGWWKIRY-QGKEGWAPASYLK 276
Cdd:cd11819   3 KALYDYQAAEDNEISFVEGDIITQIEQIDEGWWLGVNaKGQKGLFPANYVE 53

Second Src Homology 3 domain (SH3B) of CD2-associated protein and similar proteins; This subfamily is composed of the second SH3 domain (SH3B) 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. SH3B of both proteins have been shown to bind to Cbl. In the case of CD2AP, its SH3B binds to Cbl at a site distinct from the c-Cbl/SH3A binding site. The CIN85 SH3B also binds 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.

Pssm-ID: 212807 [Multi-domain] Cd Length: 53 Bit Score: 36.93 E-value: 2.01e-03

                        10        20        30
                ....*....|....*....|....*....|..
gi 63055065 159 VVADYQKQESSEISLSVGQVVDIIEKNESGWW 190
Cdd:cd11874   4 VLFSYTPQNEDELELKVGDTIEVLGEVEEGWW 35

Src Homology 3 domain of beta-Pak Interactive eXchange factor; Beta-PIX, also called Rho guanine nucleotide exchange factor 7 (ARHGEF7) or Cool (Cloned out of Library)-1, activates small GTPases by exchanging bound GDP for free GTP. It acts as a GEF for both Cdc42 and Rac 1, and plays important 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.

Pssm-ID: 212994 [Multi-domain] Cd Length: 54 Bit Score: 36.97 E-value: 2.09e-03

                        10        20        30        40
                ....*....|....*....|....*....|....*....|..
gi 63055065 162 DYQKQESSEISLSVGQVVDIIEKNESGWWFVSTAEEQGWVPA 203
Cdd:cd12061   7 NFQQTNEDELSFSKGDVIHVTRVEEGGWWEGTHNGRTGWFPS 48

Src Homology 3 domain of beta-Pak Interactive eXchange factor; Beta-PIX, also called Rho guanine nucleotide exchange factor 7 (ARHGEF7) or Cool (Cloned out of Library)-1, activates small GTPases by exchanging bound GDP for free GTP. It acts as a GEF for both Cdc42 and Rac 1, and plays important 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.

Pssm-ID: 212994 [Multi-domain] Cd Length: 54 Bit Score: 36.97 E-value: 2.14e-03

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....
gi 63055065 379 FQTTIPDGISFQAGLKVEVIEKSLSGWWYIQMEDKEGWAPATFI 422
Cdd:cd12061   8 FQQTNEDELSFSKGDVIHVTRVEEGGWWEGTHNGRTGWFPSNYV 51

Src homology 3 domain of Growth Arrest Specific protein 7; GAS7 is mainly expressed in the brain and is required for neurite outgrowth. It may also play a role in the protection and migration of embryonic stem cells. Treatment-related acute myeloid leukemia (AML) has been reported resulting from mixed-lineage leukemia (MLL)-GAS7 translocations as a complication of primary cancer treatment. GAS7 contains an N-terminal SH3 domain, followed by a WW domain, and a central F-BAR 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.

Pssm-ID: 212763 [Multi-domain] Cd Length: 52 Bit Score: 37.11 E-value: 2.15e-03

                        10        20        30
                ....*....|....*....|....*....|....*..
gi 63055065 386 GISFQAGLKVEVIEKSLSGWWYIQMEDKEGWAPATFI 422
Cdd:cd11829  16 GLSFEAGELIRVLQAPDGGWWEGEKDGLRGWFPASYV 52

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.

Pssm-ID: 212714 [Multi-domain] Cd Length: 55 Bit Score: 36.90 E-value: 2.18e-03

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....
gi 63055065 226 YTVIYPYTARDQDEMNLERGAVVEVVQKNLEGWW--KIRYQGKEGWAPASYLKK 277
Cdd:cd11780   2 YRALYSYTPQNEDELELREGDIVYVMEKCDDGWFvgTSERTGLFGTFPGNYVAR 55

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.

Pssm-ID: 212760 [Multi-domain] Cd Length: 52 Bit Score: 36.92 E-value: 2.31e-03

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|..
gi 63055065 853 VAVANFEGD-EDTSSFQEGTVFEVREKNSSGWWFcQVLSGApswEGWIPSNY 903
Cdd:cd11826   3 VALYDYTADkDDELSFQEGDIIYVTKKNDDGWYE-GVLNGV---TGLFPGNY 50

Src homology 3 domain of High osmolarity signaling protein Sho1p; Sho1p (or Sho1), also called SSU81 (Suppressor of SUA8-1 mutation), is a yeast membrane protein that regulates adaptation to high salt conditions by activating the HOG (high-osmolarity glycerol) pathway. High salt concentrations lead to the localization to the membrane of the MAPKK Pbs2, which is then activated by the MAPKK Ste11 and in turn, activates the MAPK Hog1. Pbs2 is localized to the membrane though the interaction of its PxxP motif with the SH3 domain of Sho1p. 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.

Pssm-ID: 212789 [Multi-domain] Cd Length: 55 Bit Score: 37.01 E-value: 2.33e-03

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|.
gi 63055065 229 IYPYTARDQD--EMNLERGAVVEVvqKNLEG-WWKIRYQ-GKEGWAPASYL 275
Cdd:cd11855   5 LYPYDASPDDpnELSFEKGEILEV--SDTSGkWWQARKSnGETGICPSNYL 53

Src homology 3 domain of the Rho guanine nucleotide exchange factors ARHGEF16 and ARHGEF26; ARHGEF16, also called ephexin-4, acts as a GEF for RhoG, activating it by exchanging bound GDP for free GTP. RhoG is a small GTPase that is a crucial regulator of Rac in migrating cells. ARHGEF16 interacts directly with the ephrin receptor EphA2 and mediates cell migration and invasion in breast cancer cells by activating RhoG. ARHGEF26, also called SGEF (SH3 domain-containing guanine exchange factor), also activates RhoG. It is highly expressed in liver and may play a role in regulating membrane dynamics. ARHGEF16 and ARHGEF26 contain RhoGEF (also called Dbl-homologous or DH), Pleckstrin Homology (PH), and SH3 domains. The SH3 domains of ARHGEFs play an autoinhibitory role through intramolecular interactions with a proline-rich region N-terminal to the DH domain. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

Pssm-ID: 212871 Cd Length: 55 Bit Score: 37.13 E-value: 2.39e-03

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|..
gi 63055065 228 VIYPYTARDQDEMNLERGAVVEVVQKNLEGWW---KIRyQGKEGWAPASYLK 276
Cdd:cd11938   4 IIKAYTAKQPDELSLQQADVVLVLQTESDGWYygeRLR-DGERGWFPSSCAK 54

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.

Pssm-ID: 212739 [Multi-domain] Cd Length: 53 Bit Score: 36.84 E-value: 2.63e-03

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*...
gi 63055065 230 YPYTARDQDEMNLERGAVVEVVQKNLEGWWKIRYQGKEGWAPASYLKK 277
Cdd:cd11805   6 YDFNPQEPGELEFRRGDIITVLDSSDPDWWKGELRGRVGIFPANYVQP 53

Src homology 3 domain of CAS (Crk-Associated Substrate) scaffolding protein family member, Embryonal Fyn-associated Substrate; EFS is also called HEFS, CASS3 (Cas scaffolding protein family member 3) or SIN (Src-interacting protein). It was identified based on interactions with the Src kinases, Fyn and Yes. It plays a role in thymocyte development and acts as a negative regulator of T cell proliferation. CAS proteins function as molecular scaffolds to regulate protein complexes that are involved in many cellular processes. They share a common domain structure that includes an N-terminal SH3 domain, an unstructured substrate domain that contains many YxxP motifs, a serine-rich four-helix bundle, and a FAT-like C-terminal domain. The SH3 domain of CAS proteins binds to diverse partners including FAK, FRNK, Pyk2, PTP-PEST, DOCK180, 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.

Pssm-ID: 212936 Cd Length: 62 Bit Score: 37.18 E-value: 2.74e-03

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|.
gi 63055065 229 IYPYTARDQDEMNLERGAVVEVVQKN---LEGWWKIRYQGKEGWAPASYLK 276
Cdd:cd12003   6 LYDNAAESPEELSFRRGDVLMVLKREhgsLPGWWLCSLHGQQGIAPANRLR 56

First Src Homology 3 domain (SH3A) of Cbl-interacting protein of 85 kDa; CIN85, also called SH3 domain-containing kinase-binding protein 1 (SH3KBP1) or CD2-binding protein 3 (CD2BP3) or Ruk, is an adaptor protein that is involved in the downregulation of receptor tyrosine kinases by facilitating endocytosis through interaction with endophilin-associated ubiquitin ligase Cbl proteins. It is also important in many other cellular processes including vesicle-mediated transport, cytoskeletal remodelling, apoptosis, cell adhesion and migration, and viral infection, among others. CIN85 exists as multiple variants from alternative splicing; the main variant contains three SH3 domains, a proline-rich region, and a C-terminal coiled-coil domain. All of these domains enable CIN85 to bind various protein partners and assemble complexes that have been implicated in many different functions. This alignment model represents the first SH3 domain (SH3A) of CIN85; SH3A binds to internal proline-rich motifs within the proline-rich region. This intramolecular interaction serves as a regulatory mechanism to keep CIN85 in a closed conformation, preventing the recruitment of other proteins. SH3A has also been shown to bind ubiquitin and to an atypical PXXXPR motif at the C-terminus of Cbl and the cytoplasmic end of the cell adhesion protein CD2. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

Pssm-ID: 212985 [Multi-domain] Cd Length: 53 Bit Score: 36.80 E-value: 2.75e-03

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|
gi 63055065 228 VIYPYTARDQDEMNLERGAVVEVVQKNLEGWWKIRYQGKEGWAPASYLKK 277
Cdd:cd12052   4 VEFDYKAQHEDELTITVGDIITKIKKDDGGWWEGEIKGRRGLFPDNFVRE 53

Src homology 3 domain of the Rho guanine nucleotide exchange factors ARHGEF5 and ARHGEF19; ARHGEF5, also called ephexin-3 or TIM (Transforming immortalized mammary oncogene), is a potent activator of RhoA and it plays roles in regulating cell shape, adhesion, and migration. It binds to the SH3 domain of Src and is involved in regulating Src-induced podosome formation. ARHGEF19, also called ephexin-2 or WGEF (weak-similarity GEF), is highly expressed in the intestine, liver, heart and kidney. It activates RhoA, Cdc42, and Rac 1, and has been shown to activate RhoA in the Wnt-PCP (planar cell polarity) pathway. It is involved in the regulation of cell polarity and cytoskeletal reorganization. ARHGEF5 and ARHGEF19 contain RhoGEF (also called Dbl-homologous or DH), Pleckstrin Homology (PH), and SH3 domains. The SH3 domains of ARHGEFs play an autoinhibitory role through intramolecular interactions with a proline-rich region N-terminal to the DH domain. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

Pssm-ID: 212873 Cd Length: 55 Bit Score: 36.69 E-value: 2.96e-03

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|
gi 63055065 229 IYPYTARDQDEMNLERGAVVEVVQKNLEGWWK-IRYQ-GKEGWAPASYLK 276
Cdd:cd11940   5 IRSYKAQENDELTLEKADIIMVRQQSSDGWLEgVRLSdGERGWFPQSHVE 54

Src homology 3 domain of Protein arginine N-methyltransferase 2; PRMT2, also called HRMT1L1, belongs to the arginine methyltransferase protein family. It functions as a coactivator to both estrogen receptor alpha (ER-alpha) and androgen receptor (AR), presumably through arginine methylation. The ER-alpha transcription factor is involved in cell proliferation, differentiation, morphogenesis, and apoptosis, and is also implicated in the development and progression of breast cancer. PRMT2 and its variants are upregulated in breast cancer cells and may be involved in modulating the ER-alpha signaling pathway during formation of breast cancer. PRMT2 also plays a role in regulating the function of E2F transcription factors, which are critical cell cycle regulators, by binding to the retinoblastoma gene product (RB). It contains an N-terminal SH3 domain and an AdoMet binding 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.

Pssm-ID: 212740 [Multi-domain] Cd Length: 53 Bit Score: 36.60 E-value: 3.03e-03

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....
gi 63055065 852 YVAVANFEG-DEDTSSFQEGTVFEVREKNSSGWWFCQvLSGApswEGWIPSNYL 904
Cdd:cd11806   2 YVAIADFVAtDDSQLSFESGDKLLVLRKPSVDWWWAE-HNGC---CGYIPASHL 51

The phosphoinositide binding Phox Homology domain of Sorting Nexin 8 and yeast Mvp1p; The PX domain is a phosphoinositide (PI) binding module present in many proteins with diverse functions. Sorting nexins (SNXs) make up the largest group among PX domain containing proteins. They are involved in regulating membrane traffic and protein sorting in the endosomal system. The PX domain of SNXs binds PIs and targets the protein to PI-enriched membranes. SNXs differ from each other in PI-binding specificity and affinity, and the presence of other protein-protein interaction domains, which help determine subcellular localization and specific function in the endocytic pathway. Some SNXs are localized in early endosome structures such as clathrin-coated pits, while others are located in late structures of the endocytic pathway. SNX8 and the yeast counterpart Mvp1p are involved in sorting and delivery of late-Golgi proteins, such as carboxypeptidase Y, to vacuoles.

Pssm-ID: 132776 Cd Length: 105 Bit Score: 37.98 E-value: 3.32e-03

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 63055065   6 SIVEVKVLDvQKRRVPNKHYVYIIRvtwSSGATEAIYRRYSKFFDLQMQMLDKFPMeggqkdpkqRIIPFLPGK-ILFR- 83
Cdd:cd06866   1 DTVTVELVP-EKKGLFLKHVEYEVS---SKRFKSTVYRRYSDFVWLHEYLLKRYPY---------RMVPALPPKrIGGSa 67

                        90       100       110       120
                ....*....|....*....|....*....|....*....|....*.
gi 63055065  84 -RSHI--RDVAVKRLIpideyckALIQLPPYISQcDEVLQFFETRP 126
Cdd:cd06866  68 dREFLeaRRRGLSRFL-------NLVARHPVLSE-DELVRTFLTEP 105

Src homology 3 domain of SH3 and multiple ankyrin repeat domains (Shank) proteins; Shank proteins carry scaffolding functions through multiple sites of protein-protein interaction in its domain architecture, including ankyrin (ANK) repeats, a long proline rich region, as well as SH3, PDZ, and SAM domains. They bind a variety of membrane and cytosolic proteins, and exist in alternatively spliced isoforms. They are highly enriched in postsynaptic density (PSD) where they interact with the cytoskeleton and with postsynaptic membrane receptors including NMDA and glutamate receptors. They are crucial in the construction and organization of the PSD and dendritic spines of excitatory synapses. There are three members of this family (Shank1, Shank2, Shank3) which show distinct and cell-type specific patterns of expression. Shank1 is brain-specific; Shank2 is found in neurons, glia, endocrine cells, liver, and kidney; Shank3 is widely expressed. The SH3 domain of Shank binds GRIP, a scaffold protein that binds AMPA receptors and Eph receptors/ligands. 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.

Pssm-ID: 212766 Cd Length: 50 Bit Score: 36.26 E-value: 3.39e-03

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*...
gi 63055065 225 KYTVIYPYTARDQDEMNLERGAVVEVVQKNLEGWWKIRYQGKEGWAPA 272
Cdd:cd11832   1 YFIAVKSYSPQEEGEISLHKGDRVKVLSIGEGGFWEGSVRGRTGWFPS 48

Src Homology 3 domain of GTPase Regulator Associated with Focal adhesion kinase 2; GRAF2, also called Rho GTPase activating protein 10 (ARHGAP10) or PS-GAP, is a GAP with activity towards Cdc42 and RhoA. It regulates caspase-activated p21-activated protein kinase-2 (PAK-2p34). GRAF2 interacts with PAK-2p34, leading to its stabilization and decrease of cell death. It is highly expressed in skeletal muscle, and is involved in alpha-catenin recruitment at cell-cell junctions. GRAF2 contains an N-terminal BAR domain, followed by a Pleckstrin homology (PH) domain, a Rho GAP domain, and a C-terminal SH3 domain. The SH3 domain of GRAF 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.

Pssm-ID: 212998 [Multi-domain] Cd Length: 54 Bit Score: 36.50 E-value: 3.42e-03

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|...
gi 63055065 225 KYTVIYPYTARDQDEMNLERGAVVEVVQKNLE-GWWKIRYQGKEGWAPASYLK 276
Cdd:cd12065   1 KAKAVYPCEAEHSSELSFEVGAIFEDVTLSREpGWLEGTLNGKRGLIPENYVE 53

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.

Pssm-ID: 212706 [Multi-domain] Cd Length: 53 Bit Score: 36.51 E-value: 3.46e-03

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....
gi 63055065 852 YVAVANFEGDE-DTSSFQEGTVFEVREKNSSGWWfcQVLSGAPSweGWIPSNYL 904
Cdd:cd11772   2 FRALYDYEAQHpDELSFEEGDLLYISDKSDPNWW--KATCGGKT--GLIPSNYV 51

Src homology 3 domain of Slit-Robo GTPase Activating Proteins 1, 2, and 3; srGAP1, also called Rho GTPase-Activating Protein 13 (ARHGAP13), is a Cdc42- and RhoA-specific GAP and is expressed later in the development of central nervous system tissues. srGAP2 is expressed in zones of neuronal differentiation. It plays a role in the regeneration of neurons and axons. srGAP3, also called MEGAP (MEntal disorder associated GTPase-Activating Protein), is a Rho GAP with activity towards Rac1 and Cdc42. It impacts cell migration by regulating actin and microtubule cytoskeletal dynamics. The association between srGAP3 haploinsufficiency and mental retardation is under debate. srGAPs are Rho GAPs that interact with Robo1, the transmembrane receptor of Slit proteins. Slit proteins are secreted proteins that control axon guidance and the migration of neurons and leukocytes. srGAPs contain an N-terminal F-BAR domain, a Rho GAP 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.

Pssm-ID: 212888 [Multi-domain] Cd Length: 53 Bit Score: 36.46 E-value: 3.51e-03

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*.
gi 63055065 230 YPYTARDQDEMNLERGAVVEVVQKNLEGWWKIRYQGKEGWAPASYL 275
Cdd:cd11955   6 FDYVGRSARELSFKKGASLLLYHRASDDWWEGRHNGIDGLVPHQYI 51

First C-terminal Src homology 3 domain of SH3 and cysteine-rich domain-containing (Stac) proteins; Stac proteins are putative adaptor proteins that contain a cysteine-rich C1 domain and one or two SH3 domains at the C-terminus. There are three mammalian members (Stac1, Stac2, and Stac3) of this family. Stac1 and Stac3 contain two SH3 domains while Stac2 contains a single SH3 domain at the C-terminus. This model represents the first C-terminal SH3 domain of Stac1 and Stac3, and the single C-terminal SH3 domain of Stac2. Stac1 and Stac2 have been found to be expressed differently in mature dorsal root ganglia (DRG) neurons. Stac1 is mainly expressed in peptidergic neurons while Stac2 is found in a subset of nonpeptidergic and all trkB+ neurons. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

Pssm-ID: 212767 [Multi-domain] Cd Length: 53 Bit Score: 36.33 E-value: 3.52e-03

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|..
gi 63055065 373 YYTIAEFQTTIPDGISFQAGLKVEVIEKSLSGWWYIQMEDKEGWAPATFIDK 424
Cdd:cd11833   2 YVALYKFKPQENEDLEMRPGDKITLLDDSNEDWWKGKIEDRVGFFPANFVQR 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.

Pssm-ID: 212806 [Multi-domain] Cd Length: 53 Bit Score: 36.48 E-value: 3.65e-03

                        10        20        30
                ....*....|....*....|....*....|....
gi 63055065 157 YVVVADYQKQESSEISLSVGQVVDIIEKNESGWW 190
Cdd:cd11873   2 VIVEFDYDAEEPDELTLKVGDIITNVKKMEEGWW 35

Variant SH3 domain;

Pssm-ID: 434066 [Multi-domain] Cd Length: 49 Bit Score: 36.06 E-value: 3.77e-03

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*
gi 63055065   379 FQTTIPDGISFQAGLKVEVIEKSLSGWWYIQMEDKEGWAPATFID 423
Cdd:pfam14604   5 YEPKDDDELSLQRGDVITVIEESEDGWWEGINTGRTGLVPANYVE 49

Src Homology 3 domain of Sdc25/Cdc25 guanine nucleotide exchange factors; This subfamily is composed of the Saccharomyces cerevisiae guanine nucleotide exchange factors (GEFs) Sdc25 and Cdc25, and similar proteins. These GEFs regulate Ras by stimulating the GDP/GTP exchange on Ras. Cdc25 is involved in the Ras/PKA pathway that plays an important role in the regulation of metabolism, stress responses, and proliferation, depending on available nutrients and conditions. Proteins in this subfamily contain an N-terminal SH3 domain as well as REM (Ras exchanger motif) and RasGEF domains at the C-terminus. SH3 domains bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs; they play a role in the regulation of enzymes by intramolecular interactions, changing the subcellular localization of signal pathway components and mediate multiprotein complex assemblies.

Pssm-ID: 212816 Cd Length: 55 Bit Score: 36.49 E-value: 3.80e-03

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|.
gi 63055065 376 IAEFQTTIPDGISFQAGLKVEVIEKSLSGWW-----YIQMEDKEGWAPATF 421
Cdd:cd11883   5 LYDFTPKSKNQLSFKAGDIIYVLNKDPSGWWdgviiSSSGKVKRGWFPSNY 55

Src homology 3 domain of Brk (Breast tumor kinase) Protein Tyrosine Kinase (PTK), also called PTK6; Brk is a cytoplasmic (or non-receptor) PTK with limited homology to Src kinases. It has been found to be overexpressed in a majority of breast tumors. It plays roles in normal cell differentiation, proliferation, survival, migration, and cell cycle progression. Brk substrates include RNA-binding proteins (SLM-1/2, Sam68), transcription factors (STAT3/5), and signaling molecules (Akt, paxillin, IRS-4). Src kinases in general 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 site. 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.

Pssm-ID: 212781 [Multi-domain] Cd Length: 58 Bit Score: 36.38 E-value: 3.84e-03

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*.
gi 63055065 225 KYTVIYPYTARDQDEMNLERGAVVEVVQKNLEGWW--KIRYQG---KEGWAPASYL 275
Cdd:cd11847   1 IYKALWDFKARGDEELSFQAGDQFRIAERSGDWWTalKLDRAGgvvAQGFVPNNYL 56

Src homology 3 domain of APC-Stimulated guanine nucleotide Exchange Factor; ASEF, also called ARHGEF4, exists in an autoinhibited form and is activated upon binding of the tumor suppressor APC (adenomatous polyposis coli). GEFs activate small GTPases by exchanging bound GDP for free GTP. ASEF can activate Rac1 or Cdc42. Truncated ASEF, which is found in colorectal cancers, is constitutively active and has been shown to promote angiogenesis and cancer cell migration. ASEF contains a SH3 domain followed by RhoGEF (also called Dbl-homologous or DH) and Pleckstrin Homology (PH) domains. In its autoinhibited form, the SH3 domain of ASEF forms an extensive interface with the DH and PH domains, blocking the Rac 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.

Pssm-ID: 212906 [Multi-domain] Cd Length: 73 Bit Score: 36.92 E-value: 4.05e-03

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 63055065 143 GNDPTSVDPMVLEQYVVVA----DYQKQESSEISLSVGQVVDIIEKNESGWWFVSTAEEQGWVPAT 204
Cdd:cd11973   2 GGEQLAINELISDGSVVCAealwDHVTMDDQELGFKAGDVIEVMDATNKEWWWGRVLDSEGWFPAS 67

C-terminal (Fourth) Src Homology 3 domain of SH3 domain containing ring finger 1 (SH3RF1), SH3RF3, and similar domains; SH3RF1 (or POSH) and SH3RF3 (or POSH2) are scaffold proteins that function as E3 ubiquitin-protein ligases. They contain an N-terminal RING finger domain and four SH3 domains. This model represents the fourth SH3 domain, located at the C-terminus of SH3RF1 and SH3RF3, and similar domains. SH3RF1 plays a role in calcium homeostasis through the control of the ubiquitin domain protein Herp. It may also have a role in regulating death receptor mediated and JNK mediated apoptosis. SH3RF3 interacts with p21-activated kinase 2 (PAK2) and GTP-loaded Rac1. It may play a role in regulating JNK mediated apoptosis in certain conditions. 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.

Pssm-ID: 212719 Cd Length: 55 Bit Score: 36.29 E-value: 4.28e-03

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*
gi 63055065 225 KYTVIYPYTARDQDEMNLERGAVVEVVQKNLEGWWKIRYQ--GKEGWAPASYLKK 277
Cdd:cd11785   1 RYRVIVPYPPQSEAELELKEGDIVFVHKKREDGWFKGTLQrtGKTGLFPGSFVES 55

Fourth Src homology 3 domain (or SH3D) of Intersectin-2; Intersectin-2 (ITSN2) is an adaptor protein that functions in exo- and endocytosis, actin cytoskeletal reorganization, and signal transduction. It plays a role in clathrin-coated pit (CCP) formation. It binds to many proteins through its multidomain structure and facilitate the assembly of multimeric complexes. ITSN2 also functions as a specific GEF for Cdc42 activation in epithelial morphogenesis, and is required in mitotic spindle orientation. It exists in alternatively spliced short and long isoforms. The short isoform contains two Eps15 homology domains (EH1 and EH2), a coiled-coil region and five SH3 domains (SH3A-E), while the long isoform, in addition, contains RhoGEF (also called Dbl-homologous or DH), Pleckstrin homology (PH) and C2 domains. The fourth SH3 domain (or SH3D) of ITSN2 is expected to bind protein partners, similar to ITSN1 which has been shown to bind SHIP2, Numb, CdGAP, and N-WASP. 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.

Pssm-ID: 212927 Cd Length: 59 Bit Score: 36.45 E-value: 4.32e-03

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....
gi 63055065 228 VIYPYTARDQDEMNLERGAVVEVVQKNLEGWW--KIRYQGKE---GWAPASYLK 276
Cdd:cd11994   4 VTTAYVASGVEQLSLSPGQLILILKKNSSGWWlgELQARGKKrqkGWFPASHVK 57

C-terminal (or second) Src homology 3 domain of VAV3 protein; VAV3 is ubiquitously expressed and functions as a phosphorylation-dependent guanine nucleotide exchange factor (GEF) for RhoA, RhoG, and Rac1. It has been implicated to function in the hematopoietic, bone, cerebellar, and cardiovascular systems. VAV3 is essential in axon guidance in neurons that control blood pressure and respiration. It is overexpressed in prostate cancer cells and it plays a role in regulating androgen receptor transcriptional activity. 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.

Pssm-ID: 212911 [Multi-domain] Cd Length: 56 Bit Score: 36.16 E-value: 4.36e-03

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*..
gi 63055065 162 DYQKQESSEISLSVGQVVDI-IEKNESGWWFVSTAEEQGWVPATCLE 207
Cdd:cd11978   8 DFCARDMRELSLLKGDVVKIyTKMSTNGWWRGEVNGRVGWFPSTYVE 54

Src homology 3 domain of Protein arginine N-methyltransferase 2; PRMT2, also called HRMT1L1, belongs to the arginine methyltransferase protein family. It functions as a coactivator to both estrogen receptor alpha (ER-alpha) and androgen receptor (AR), presumably through arginine methylation. The ER-alpha transcription factor is involved in cell proliferation, differentiation, morphogenesis, and apoptosis, and is also implicated in the development and progression of breast cancer. PRMT2 and its variants are upregulated in breast cancer cells and may be involved in modulating the ER-alpha signaling pathway during formation of breast cancer. PRMT2 also plays a role in regulating the function of E2F transcription factors, which are critical cell cycle regulators, by binding to the retinoblastoma gene product (RB). It contains an N-terminal SH3 domain and an AdoMet binding 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.

Pssm-ID: 212740 [Multi-domain] Cd Length: 53 Bit Score: 36.21 E-value: 4.68e-03

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|.
gi 63055065 372 EYYTIAEFQTTIPDGISFQAGLKVEVIEKSLSGWWYIQMEDKEGWAPATFI 422
Cdd:cd11806   1 EYVAIADFVATDDSQLSFESGDKLLVLRKPSVDWWWAEHNGCCGYIPASHL 51

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.

Pssm-ID: 212881 [Multi-domain] Cd Length: 54 Bit Score: 35.95 E-value: 4.88e-03

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....
gi 63055065 853 VAVANFEGDE-DTSSFQEGTVFEVREKNSSGWWFCQVLSGApswEGWIPSNYLR 905
Cdd:cd11948   3 VALYSFQATEsDELPFQKGDILKILNMEDDQNWYKAELQGR---EGYIPKNYIK 53

Src homology 3 domain of ARHGEF9-like Rho guanine nucleotide exchange factors; Members of this family contain a SH3 domain followed by RhoGEF (also called Dbl-homologous or DH) and Pleckstrin Homology (PH) domains. They include the Rho guanine nucleotide exchange factors ARHGEF9, ASEF (also called ARHGEF4), ASEF2, and similar proteins. GEFs activate small GTPases by exchanging bound GDP for free GTP. ARHGEF9 specifically activates Cdc42, while both ASEF and ASEF2 can activate Rac1 and Cdc42. ARHGEF9 is highly expressed in the brain and it interacts with gephyrin, a postsynaptic protein associated with GABA and glycine receptors. ASEF plays a role in angiogenesis and cell migration. ASEF2 is important in cell migration and adhesion dynamics. ASEF exists in an autoinhibited form and is activated upon binding of the tumor suppressor APC (adenomatous polyposis coli), leading to the activation of Rac1 or Cdc42. In its autoinhibited form, the SH3 domain of ASEF forms an extensive interface with the DH and PH domains, blocking the Rac 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.

Pssm-ID: 212762 [Multi-domain] Cd Length: 53 Bit Score: 35.82 E-value: 5.05e-03

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*
gi 63055065 861 DEDTSSFQEGTVFEVREKNSSGWWFCQVLSGapswEGWIPSNYLR 905
Cdd:cd11828  12 DPEELGFKAGDVIEVLDMSDKDWWWGSIRDE----EGWFPASFVR 52

Src Homology 3 domain of Tec-like Protein Tyrosine Kinases; The Tec (Tyrosine kinase expressed in hepatocellular carcinoma) subfamily is composed of Tec, Btk, Bmx (Etk), Itk (Tsk, Emt), Rlk (Txk), and similar proteins. They are cytoplasmic (or nonreceptor) tyr kinases containing Src homology protein interaction domains (SH3, SH2) N-terminal to the catalytic tyr kinase domain. Most Tec subfamily members (except Rlk) also contain an N-terminal pleckstrin homology (PH) domain, which binds the products of PI3K and allows membrane recruitment and activation. In addition, some members contain the Tec homology (TH) domain, which contains proline-rich and zinc-binding regions. Tec kinases are expressed mainly by haematopoietic cells, although Tec and Bmx are also found in endothelial cells. B-cells express Btk and Tec, while T-cells express Itk, Txk, and Tec. Collectively, Tec kinases are expressed in a variety of myeloid cells such as mast cells, platelets, macrophages, and dendritic cells. Each Tec kinase shows a distinct cell-type pattern of expression. The function of Tec kinases in lymphoid cells have been studied extensively. They play important roles in the development, differentiation, maturation, regulation, survival, and function of B-cells and T-cells. 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.

Pssm-ID: 212702 [Multi-domain] Cd Length: 54 Bit Score: 35.71 E-value: 5.47e-03

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|
gi 63055065 158 VVVA--DYQKQESSEISLSVGQVVDIIEKNESGWWFVSTAE-EQGWVPAT 204
Cdd:cd11768   1 IVVAlyDFQPIEPGDLPLEKGEEYVVLDDSNEHWWRARDKNgNEGYIPSN 50

Src Homology 3 (SH3) domain of Inhibitor of ASPP protein (iASPP); iASPP, also called RelA-associated inhibitor (RAI), is an oncoprotein that inhibits the apoptotic transactivation potential of p53. It is upregulated in human breast cancers expressing wild-type p53, in acute leukemias regardless of the p53 mutation status, as well as in ovarian cancer where it is associated with poor patient outcome and chemoresistance. iASPP is also a binding partner and negative regulator of p65RelA, which promotes cell proliferation and inhibits apoptosis; p65RelA has the opposite effect on cell growth compared to the p53 family. It contains a proline-rich region, four ankyrin (ANK) repeats, and an SH3 domain at its C-terminal half. The SH3 domain and the ANK repeats of iASPP contribute to the p53 binding site; they bind to the DNA binding domain of p53. 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.

Pssm-ID: 212885 [Multi-domain] Cd Length: 56 Bit Score: 36.06 E-value: 5.73e-03

                        10        20        30        40
                ....*....|....*....|....*....|....*....|...
gi 63055065 162 DYQKQESSEISLSVGQVVDIIEKN--ESGWWFVSTAEEQGWVP 202
Cdd:cd11952   8 DYSAEFPDELSFKEGDMVTVLRKDgeGTDWWWASLCGREGYVP 50

N-terminal Src Homology 3 domain of Ct10 Regulator of Kinase adaptor proteins; CRK adaptor proteins consists of SH2 and SH3 domains, which bind tyrosine-phosphorylated peptides and proline-rich motifs, respectively. They function downstream of protein tyrosine kinases in many signaling pathways started by various extracellular signals, including growth and differentiation factors. Cellular CRK (c-CRK) contains a single SH2 domain, followed by N-terminal and C-terminal SH3 domains. It is involved in the regulation of many cellular processes including cell growth, motility, adhesion, and apoptosis. CRK has been implicated in the malignancy of various human cancers. The N-terminal SH3 domain of CRK binds a number of target proteins including DOCK180, C3G, SOS, and cABL. The CRK family includes two alternatively spliced protein forms, CRKI and CRKII, that are expressed by the CRK gene, and the CRK-like (CRKL) protein, which is expressed by a distinct gene (CRKL). 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.

Pssm-ID: 212692 [Multi-domain] Cd Length: 55 Bit Score: 35.80 E-value: 5.94e-03

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....
gi 63055065 854 AVANFEG-DEDTSSFQEGTVFEVREKNSSGWWFCQVLSGApswEGWIPSNYLRK 906
Cdd:cd11758   5 ALFDFPGnDDEDLPFKKGEILTVIRKPEEQWWNARNSEGK---TGMIPVPYVEK 55

Src homology 3 domain of APC-Stimulated guanine nucleotide Exchange Factor; ASEF, also called ARHGEF4, exists in an autoinhibited form and is activated upon binding of the tumor suppressor APC (adenomatous polyposis coli). GEFs activate small GTPases by exchanging bound GDP for free GTP. ASEF can activate Rac1 or Cdc42. Truncated ASEF, which is found in colorectal cancers, is constitutively active and has been shown to promote angiogenesis and cancer cell migration. ASEF contains a SH3 domain followed by RhoGEF (also called Dbl-homologous or DH) and Pleckstrin Homology (PH) domains. In its autoinhibited form, the SH3 domain of ASEF forms an extensive interface with the DH and PH domains, blocking the Rac 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.

Pssm-ID: 212906 [Multi-domain] Cd Length: 73 Bit Score: 36.53 E-value: 6.19e-03

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*
gi 63055065 861 DEDTSSFQEGTVFEVREKNSSGWWFCQVLSGapswEGWIPSNYLR 905
Cdd:cd11973  30 DDQELGFKAGDVIEVMDATNKEWWWGRVLDS----EGWFPASFVR 70

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.

Pssm-ID: 212764 [Multi-domain] Cd Length: 54 Bit Score: 35.68 E-value: 6.28e-03

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*..
gi 63055065 162 DYQKQESSEISLSVGQVVDIIEK-NESGWWFVSTAEEQGWVPATCLE 207
Cdd:cd11830   7 DFCARDMRELSLKEGDVVKIYNKkGQQGWWRGEINGRIGWFPSTYVE 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.

Pssm-ID: 212727 [Multi-domain] Cd Length: 55 Bit Score: 35.39 E-value: 7.81e-03

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|
gi 63055065 156 QYVVVADYQKQESSEISLSVGQVVDIIEKNESGWWFVSTAE--EQGWVPA 203
Cdd:cd11793   1 QVQCVHAYTAQQPDELTLEEGDVVNVLRKMPDGWYEGERLRdgERGWFPS 50

Src homology 3 domain of the Rho guanine nucleotide exchange factor ARHGEF9; ARHGEF9, also called PEM2 or collybistin, selectively activates Cdc42 by exchanging bound GDP for free GTP. It is highly expressed in the brain and it interacts with gephyrin, a postsynaptic protein associated with GABA and glycine receptors. Mutations in the ARHGEF9 gene cause X-linked mental retardation with associated features like seizures, hyper-anxiety, aggressive behavior, and sensory hyperarousal. ARHGEF9 contains a SH3 domain followed by RhoGEF (also called Dbl-homologous or DH) and Pleckstrin Homology (PH) domains. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

Pssm-ID: 212908 Cd Length: 62 Bit Score: 35.84 E-value: 8.38e-03

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                ....*....|....*....|....*....|....*....|....*
gi 63055065 160 VADYQKQESSEISLSVGQVVDIIEKNESGWWFVSTAEEQGWVPAT 204
Cdd:cd11975  10 VWDHVTMANRELAFKAGDVIKVLDASNKDWWWGQIDDEEGWFPAS 54

Fourth Src homology 3 domain (or SH3D) 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 fourth SH3 domain (or SH3D) of ITSN1 has been shown to bind SHIP2, Numb, CdGAP, and N-WASP. 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.

Pssm-ID: 212773 [Multi-domain] Cd Length: 58 Bit Score: 35.39 E-value: 8.49e-03

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                ....*....|....*....|....*....|....*....|..
gi 63055065 866 SFQEGTVFEVREKNSSGWWFCQVLSGAPSWE-GWIPSNYLRK 906
Cdd:cd11839  17 SLAVGQLVLVRKKSPSGWWEGELQARGKKRQiGWFPANYVKL 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.

Pssm-ID: 212895 [Multi-domain] Cd Length: 54 Bit Score: 35.54 E-value: 8.60e-03

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                ....*....|....*....|....*....|....*....|....*....|.
gi 63055065 227 TVIYPYTARDQDEMNLERGAVVEVVQKNLEGWWK-IRYQGKEGWAPASYLK 276
Cdd:cd11962   3 VVLYDYEKDEDNEIELVEGEIVTNIEMVDEDWWMgTNSKGESGLFPSNYVE 53

C-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 C-terminal SH3 domains (SH3c) of the related proteins, 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.

Pssm-ID: 212884 Cd Length: 53 Bit Score: 35.16 E-value: 8.70e-03

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*.
gi 63055065 230 YPYTARDQDEMNLERGAVVEVVQKNLEGWWKIRYQGKEGWAPASYL 275
Cdd:cd11951   6 YDFSAEDPSQLSFRRGDIIEVLDCPDPNWWRGRISGRVGFFPRNYV 51

Src Homology 3 domain of SH3 domain-containing protein 21 (SH3D21) and similar proteins; N-terminal SH3 domain of the uncharacterized protein SH3 domain-containing protein 21, and similar uncharacterized domains, it belongs to the CD2AP-like_3 subfamily of proteins. The CD2AP-like_3 subfamily is composed of the third SH3 domain (SH3C) 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. SH3C of both proteins have been shown to bind to 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.

Pssm-ID: 213018 [Multi-domain] Cd Length: 55 Bit Score: 35.52 E-value: 8.79e-03

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                ....*....|....*....|....*....|....*....|....*...
gi 63055065 157 YVVVADYQKQESSEISLSVGQVVDIIEKN--ESGWWFVSTAEEQGWVP 202
Cdd:cd12142   2 CRVLFDYNPVAPDELALKKGDVIEVISKEteDEGWWEGELNGRRGFFP 49

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.

Pssm-ID: 429575 [Multi-domain] Cd Length: 54 Bit Score: 35.26 E-value: 8.90e-03

                          10        20        30
                  ....*....|....*....|....*....|....*....
gi 63055065   384 PDGISFQAGLKVEVIEKSLSGWWYIQMEDKEGWAPATFI 422
Cdd:pfam07653  13 KNGLTLKKGDVVKVLGKDNDGWWEGETGGRVGLVPSTAV 51

Src Homology 3 domain of Tec (Tyrosine kinase expressed in hepatocellular carcinoma); Tec is a cytoplasmic (or nonreceptor) tyr kinase containing Src homology protein interaction domains (SH3, SH2) N-terminal to the catalytic tyr kinase domain. It also contains an N-terminal pleckstrin homology (PH) domain, which binds the products of PI3K and allows membrane recruitment and activation, and the Tec homology (TH) domain, which contains proline-rich and zinc-binding regions. It is more widely-expressed than other Tec subfamily kinases. Tec is found in endothelial cells, both B- and T-cells, and a variety of myeloid cells including mast cells, erythroid cells, platelets, macrophages and neutrophils. Tec is a key component of T-cell receptor (TCR) signaling, and is important in TCR-stimulated proliferation, IL-2 production and phospholipase C-gamma1 activation. 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.

Pssm-ID: 212838 [Multi-domain] Cd Length: 56 Bit Score: 35.18 E-value: 9.11e-03

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                ....*....|....*....|....*....|....*....|....*....|....*
gi 63055065 158 VVVA--DYQKQESSEISLSVGQVVDIIEKNESGWWFVSTAE-EQGWVPATCLEGQ 209
Cdd:cd11905   2 IVVAmyDFQPTEPHDLRLETGEEYVILEKNDVHWWKARDKYgKEGYIPSNYVTGK 56

First or N-terminal Src homology 3 domain of Nox Organizing protein 1; Nox Organizing protein 1 (NoxO1) is a critical regulator of enzyme kinetics of the nonphagocytic NADPH oxidase Nox1, which catalyzes the transfer of electrons from NADPH to molecular oxygen to form superoxide. Nox1 is expressed in colon, stomach, uterus, prostate, and vascular smooth muscle cells. NoxO1 is involved in targeting activator subunits (such as NoxA1) to Nox1. It is co-localized with Nox1 in the membranes of resting cells and directs the subcellular localization of Nox1. NoxO1 contains an N-terminal Phox homology (PX) domain, tandem SH3 domains (N-SH3 and C-SH3), and a C-terminal proline-rich region (PRR). This model characterizes the first SH3 domain (or N-SH3) of NoxO1. The tandem SH3 domains of NoxO1 interact with the PRR of p22phox, which also complexes with Nox1. 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.

Pssm-ID: 212956 Cd Length: 56 Bit Score: 35.23 E-value: 9.31e-03

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                ....*....|....*....|....*....|....*....|....*....|....
gi 63055065 157 YVVVADYQKQESSEISLSV--GQVVDIIEKNESGWWFVSTAEEQ-GWVPATCLE 207
Cdd:cd12023   2 YRCLAPFETKDTKNKPFKAaaQESLDVLLKDPTGWWLVENEDRQiAWFPAPYLE 55

Src homology 3 domain of Protein kinase C and Casein kinase Substrate in Neurons (PACSIN) proteins; PACSINs, also called Synaptic dynamin-associated proteins (Syndapins), act as regulators of cytoskeletal and membrane dynamics. They bind both dynamin and Wiskott-Aldrich syndrome protein (WASP), and may provide direct links between the actin cytoskeletal machinery through WASP and dynamin-dependent endocytosis. Vetebrates harbor three isoforms with distinct expression patterns and specific functions. PACSINs contain an N-terminal F-BAR domain and a C-terminal SH3 domain. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

Pssm-ID: 212777 [Multi-domain] Cd Length: 53 Bit Score: 35.09 E-value: 9.34e-03

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                ....*....|....*....|....*....|....*....|....*..
gi 63055065 229 IYPYTARDQDEMNLERGAVVEVVQKNLE-GWWKIRYQGKEGWAPASY 274
Cdd:cd11843   5 LYDYEGQESDELSFKAGDILTKLEEEDEqGWCKGRLDGRVGLYPANY 51

Src homology 3 domain of the CAS (Crk-Associated Substrate) scaffolding protein family member, Breast Cancer Anti-estrogen Resistance 1; BCAR1, also called p130cas or CASS1, is the founding member of the CAS family of scaffolding proteins and was originally identified through its ability to associate with Crk. The name BCAR1 was designated because the human gene was identified in a screen for genes that promote resistance to tamoxifen. It is widely expressed and its deletion is lethal in mice. It plays a role in regulating cell motility, survival, proliferation, transformation, cancer progression, and bacterial pathogenesis. CAS proteins function as molecular scaffolds to regulate protein complexes that are involved in many cellular processes. They share a common domain structure that includes an N-terminal SH3 domain, an unstructured substrate domain that contains many YxxP motifs, a serine-rich four-helix bundle, and a FAT-like C-terminal domain. The SH3 domain of CAS proteins binds to diverse partners including FAK, FRNK, Pyk2, PTP-PEST, DOCK180, 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.

Pssm-ID: 212934 Cd Length: 68 Bit Score: 35.79 E-value: 9.43e-03

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|.
gi 63055065 229 IYPYTARDQDEMNLERGAVVEVVQKN---LEGWWKIRYQGKEGWAPASYLK 276
Cdd:cd12001   8 LYDNVAESPDELSFRKGDIMTVLERDtqgLDGWWLCSLHGRQGIVPGNRLK 58

Src homology 3 domain of Obscurin and similar proteins; Obscurin is a giant muscle protein that is concentrated at the peripheries of Z-disks and M-lines. It binds small ankyrin I, a component of the sarcoplasmic reticulum (SR) membrane. It is associated with the contractile apparatus through binding with titin and sarcomeric myosin. It plays important roles in the organization and assembly of the myofibril and the SR. Obscurin has been observed as alternatively-spliced isoforms. The major isoform in sleletal muscle, approximately 800 kDa in size, is composed of many adhesion modules and signaling domains. It harbors 49 Ig and 2 FNIII repeats at the N-terminues, a complex middle region with additional Ig domains, an IQ motif, and a conserved SH3 domain near RhoGEF and PH domains, and a non-modular C-terminus with phosphorylation motifs. The obscurin gene also encodes two kinase domains, which are not part of the 800 kDa form of the protein, but is part of smaller spliced products that present in heart muscle. 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.

Pssm-ID: 212958 Cd Length: 63 Bit Score: 35.63 E-value: 9.77e-03

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|
gi 63055065 226 YTVIYPYT--ARDQDEMNLERGAVVEVVQKNLEGWWKIRYQG------KEGWAPASYLKK 277
Cdd:cd12025   4 YIVTADYTpdGADTEAIPLEEGQYVEVLDSAHPLKWLVRTKPtkssppRQGWVSPAYLEK 63