The Bin/Amphiphysin/Rvs (BAR) domain of ArfGAP with SH3 domain, ANK repeat and PH domain containing protein 3; BAR domains are dimerization, lipid binding and curvature sensing modules found in many different proteins with diverse functions. ASAP3 (ArfGAP with SH3 domain, ANK repeat and PH domain containing protein 3) is also known as ACAP4 (ArfGAP with Coiled-coil, ANK repeat and PH domain containing protein 4), DDEFL1 (Development and Differentiation Enhancing Factor-Like 1), or centaurin beta-6. It is an Arf6-specific GTPase activating protein (GAP) and is co-localized with Arf6 in ruffling membranes upon EGF stimulation. ASAP3 is implicated in the pathogenesis of hepatocellular carcinoma and plays a role in regulating cell migration and invasion. ASAP3 contains an N-terminal BAR domain, followed by a Pleckstrin homology (PH) domain, an Arf GAP domain, ankyrin (ANK) repeats, and a C-terminal SH3 domain. BAR domains form dimers that bind to membranes, induce membrane bending and curvature, and may also be involved in protein-protein interactions. The BAR domain of the related protein ASAP1 mediates membrane bending, is essential for function, and autoinhibits GAP activity by interacting with the PH and/or Arf GAP domains.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 568931021   2 ASTLCRPMALEGDQAILQRIKKAVRAIHSSGLGHVETEEHYREAVEALGNSHLSQNSHELSTGFLNLAVFTREVAALFKN 81
Cdd:cd07640    2 STAAALEESLEGDQASLQRIKKIVKAIHNSGLNHVENEEQYTEALENLGNSHLSQNNHELSTGFLNLAVFTREVTALFKN 81

                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 568931021  82 LVQNLNNIVSFPLDSLMKGHLRDGRHDSKKHLEKAWKDYESKVAKLEKERDRARFPGG----SHGVMSQDTQRERRVFQL 157
Cdd:cd07640   82 LVQNLNNIVSFPLDSLLKGQLRDGRLESKKQMEKAWKDYEAKIGKLEKERREKQKQHGlirlDMTDTAEDMQRERRNFQL 161

                        170       180       190       200       210
                 ....*....|....*....|....*....|....*....|....*....|..
gi 568931021 158 HMCEYLVKAGESQVKQGPDFLQSLIKFFHAQHNFFQDGWKAAQSLSPFIDKL 209
Cdd:cd07640  162 HMCEYLLKAQESQMKQGPDFLQSLIKFFHAQHNFFQDGWKAAQNLGPFIEKL 213

ArfGAP with SH3 domain, ankyrin repeat and PH domain Pleckstrin homology (PH) domain; ASAPs (ASAP1, ASAP2, and ASAP3) function as an Arf-specific GAPs, participates in rhodopsin trafficking, is associated with tumor cell metastasis, modulates phagocytosis, promotes cell proliferation, facilitates vesicle budding, Golgi exocytosis, and regulates vesicle coat assembly via a Bin/Amphiphysin/Rvs domain. ASAPs contain an NH2-terminal BAR domain, a tandem PH domain/GAP domain, three ankyrin repeats, two proline-rich regions, and a COOH-terminal Src homology 3 (SH3) domain. PH domains have diverse functions, but in general are involved in targeting proteins to the appropriate cellular location or in the interaction with a binding partner. They share little sequence conservation, but all have a common fold, which is electrostatically polarized. Less than 10% of PH domains bind phosphoinositide phosphates (PIPs) with high affinity and specificity. PH domains are distinguished from other PIP-binding domains by their specific high-affinity binding to PIPs with two vicinal phosphate groups: PtdIns(3,4)P2, PtdIns(4,5)P2 or PtdIns(3,4,5)P3 which results in targeting some PH domain proteins to the plasma membrane. A few display strong specificity in lipid binding. Any specificity is usually determined by loop regions or insertions in the N-terminus of the domain, which are not conserved across all PH domains. PH domains are found in cellular signaling proteins such as serine/threonine kinase, tyrosine kinases, regulators of G-proteins, endocytotic GTPases, adaptors, as well as cytoskeletal associated molecules and in lipid associated enzymes.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 568931021 260 QHQGNKQFGTEKVGFLYKKSDG-IRRVWQKRKCGVKYGCLTISHSMINRPPVKLPLLTCQVRPNPEEKRCFDLVTHNRTY 338
Cdd:cd13251    1 QQQGNKSHGTEKSGYLLKKSEGkIRKVWQKRRCSIKDGFLTISHADENKPPAKLNLLTCQVKLVPEDKKCFDLISHNRTY 80

                         90       100
                 ....*....|....*....|....*...
gi 568931021 339 HFHAEDEQECEAWVSVLQNSKDEALSNA 366
Cdd:cd13251   81 HFQAEDENDANAWMSVLKNSKEQALNKA 108

The Bin/Amphiphysin/Rvs (BAR) domain of ArfGAP with SH3 domain, ANK repeat and PH domain containing protein 3; BAR domains are dimerization, lipid binding and curvature sensing modules found in many different proteins with diverse functions. ASAP3 (ArfGAP with SH3 domain, ANK repeat and PH domain containing protein 3) is also known as ACAP4 (ArfGAP with Coiled-coil, ANK repeat and PH domain containing protein 4), DDEFL1 (Development and Differentiation Enhancing Factor-Like 1), or centaurin beta-6. It is an Arf6-specific GTPase activating protein (GAP) and is co-localized with Arf6 in ruffling membranes upon EGF stimulation. ASAP3 is implicated in the pathogenesis of hepatocellular carcinoma and plays a role in regulating cell migration and invasion. ASAP3 contains an N-terminal BAR domain, followed by a Pleckstrin homology (PH) domain, an Arf GAP domain, ankyrin (ANK) repeats, and a C-terminal SH3 domain. BAR domains form dimers that bind to membranes, induce membrane bending and curvature, and may also be involved in protein-protein interactions. The BAR domain of the related protein ASAP1 mediates membrane bending, is essential for function, and autoinhibits GAP activity by interacting with the PH and/or Arf GAP domains.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 568931021   2 ASTLCRPMALEGDQAILQRIKKAVRAIHSSGLGHVETEEHYREAVEALGNSHLSQNSHELSTGFLNLAVFTREVAALFKN 81
Cdd:cd07640    2 STAAALEESLEGDQASLQRIKKIVKAIHNSGLNHVENEEQYTEALENLGNSHLSQNNHELSTGFLNLAVFTREVTALFKN 81

                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 568931021  82 LVQNLNNIVSFPLDSLMKGHLRDGRHDSKKHLEKAWKDYESKVAKLEKERDRARFPGG----SHGVMSQDTQRERRVFQL 157
Cdd:cd07640   82 LVQNLNNIVSFPLDSLLKGQLRDGRLESKKQMEKAWKDYEAKIGKLEKERREKQKQHGlirlDMTDTAEDMQRERRNFQL 161

                        170       180       190       200       210
                 ....*....|....*....|....*....|....*....|....*....|..
gi 568931021 158 HMCEYLVKAGESQVKQGPDFLQSLIKFFHAQHNFFQDGWKAAQSLSPFIDKL 209
Cdd:cd07640  162 HMCEYLLKAQESQMKQGPDFLQSLIKFFHAQHNFFQDGWKAAQNLGPFIEKL 213

ArfGAP with SH3 domain, ankyrin repeat and PH domain Pleckstrin homology (PH) domain; ASAPs (ASAP1, ASAP2, and ASAP3) function as an Arf-specific GAPs, participates in rhodopsin trafficking, is associated with tumor cell metastasis, modulates phagocytosis, promotes cell proliferation, facilitates vesicle budding, Golgi exocytosis, and regulates vesicle coat assembly via a Bin/Amphiphysin/Rvs domain. ASAPs contain an NH2-terminal BAR domain, a tandem PH domain/GAP domain, three ankyrin repeats, two proline-rich regions, and a COOH-terminal Src homology 3 (SH3) domain. PH domains have diverse functions, but in general are involved in targeting proteins to the appropriate cellular location or in the interaction with a binding partner. They share little sequence conservation, but all have a common fold, which is electrostatically polarized. Less than 10% of PH domains bind phosphoinositide phosphates (PIPs) with high affinity and specificity. PH domains are distinguished from other PIP-binding domains by their specific high-affinity binding to PIPs with two vicinal phosphate groups: PtdIns(3,4)P2, PtdIns(4,5)P2 or PtdIns(3,4,5)P3 which results in targeting some PH domain proteins to the plasma membrane. A few display strong specificity in lipid binding. Any specificity is usually determined by loop regions or insertions in the N-terminus of the domain, which are not conserved across all PH domains. PH domains are found in cellular signaling proteins such as serine/threonine kinase, tyrosine kinases, regulators of G-proteins, endocytotic GTPases, adaptors, as well as cytoskeletal associated molecules and in lipid associated enzymes.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 568931021 260 QHQGNKQFGTEKVGFLYKKSDG-IRRVWQKRKCGVKYGCLTISHSMINRPPVKLPLLTCQVRPNPEEKRCFDLVTHNRTY 338
Cdd:cd13251    1 QQQGNKSHGTEKSGYLLKKSEGkIRKVWQKRRCSIKDGFLTISHADENKPPAKLNLLTCQVKLVPEDKKCFDLISHNRTY 80

                         90       100
                 ....*....|....*....|....*...
gi 568931021 339 HFHAEDEQECEAWVSVLQNSKDEALSNA 366
Cdd:cd13251   81 HFQAEDENDANAWMSVLKNSKEQALNKA 108

Putative GTP-ase activating proteins for the small GTPase, ARF; Putative zinc fingers with GTPase activating proteins (GAPs) towards the small GTPase, Arf. The GAP of ARD1 stimulates GTPase hydrolysis for ARD1 but not ARFs.

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 568931021   396 EVKSRPGNDRCCDCGAADPTWLSTNLGVLTCIQCSGVHRELGVRFSRIQSLTLDLLGPSELLLALNIGNSHFNEVMEAHL 475
Cdd:smart00105   3 LLRSIPGNKKCFDCGAPNPTWASVNLGVFLCIECSGIHRSLGVHISKVRSLTLDTWTEEELRLLQKGGNENANSIWESNL 82

                           90       100       110
                   ....*....|....*....|....*....|
gi 568931021   476 PShGSPKPSAESDMSSRRNYIVAKYVEHKF 505
Cdd:smart00105  83 DD-FSLKPPDDDDQQKYESFIAAKYEEKLF 111

Ankyrin repeat [Signal transduction mechanisms];

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 568931021 551 GELALHLAirvASHASLPIVDFLIQNGGHLDAKAADGNTALHCAALHGQLDCLKLLLRGRAPVGAVNDAGETALDIARNR 630
Cdd:COG0666  153 GNTPLHLA---AANGNLEIVKLLLEAGADVNARDNDGETPLHLAAENGHLEIVKLLLEAGADVNAKDNDGKTALDLAAEN 229

                         90
                 ....*....|....
gi 568931021 631 QHKECEELLEQAQA 644
Cdd:COG0666  230 GNLEIVKLLLEAGA 243

BAR domain of APPL family; BAR_12 is the BAR coiled-coil domain at the N-terminus of APPL or adaptor protein containing PH domain, PTB domain, and leucine zipper motif proteins in higher eukaryotes. This BAR domain contains four helices whereas the other classical BAR domains contain only three helices. The first three helices form an antiparallel coiled-coil, while the fourth helix, is unique to APPL1. BAR domains take part in many varied biological processes such as fission of synaptic vesicles, endocytosis, regulation of the actin cytoskeleton, transcriptional repression, cell-cell fusion, apoptosis, secretory vesicle fusion, and tissue differentiation.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 568931021   74 EVAALFKNLVQNLNNIVSFPLDSLMKGHLRDGRhDSKKHLEKAWKDYESKVAKLekerdrARFP--GGSHGV--MSQDTQ 149
Cdd:pfam16746  85 EMENFHTILLDQAQRTIIKPLENFRKEDLKEVK-ELKKKFDKASEKLDAALEKN------AQLSkkKKPSELeeADNELA 157

                          90       100       110       120       130       140       150
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 568931021  150 RERRVFQLHMCEYLVKAGESQVKQGPDFLQSLIKFFHAQHNFFQDGWKAAQSLSPFIDKLAASVHGLRQAQEEELHKL 227
Cdd:pfam16746 158 ATRKCFHHASLDYVLQINELQERKKFEILEPLLSFMHAQFTFFHQGYELFKDLEPFMKDLQAQLQQTREDTREEKEEL 235

ADP-ribosylation factor GTPase-activating protein AGD10; Provisional

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 568931021 396 EVKSRPGNDRCCDCGAADPTWLSTNLGVLTCIQCSGVHRELGVRFSRIQSLTLDLLGPSELLLALNIGNS 465
Cdd:PLN03114  15 KLKAKSDNKICFDCNAKNPTWASVTYGIFLCIDCSAVHRSLGVHISFVRSTNLDSWSSEQLKMMIYGGNN 84

ankyrin-like protein; Provisional

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 568931021 551 GELALHLAIRVASHASLPIVDFLIQNGGHLDAKAADGNTALHCAALHGQ-LDCLKLLLRGRAPVGAVNDAGETALDI 626
Cdd:PHA03095  47 GKTPLHLYLHYSSEKVKDIVRLLLEAGADVNAPERCGFTPLHLYLYNATtLDVIKLLIKAGADVNAKDKVGRTPLHV 123

The Bin/Amphiphysin/Rvs (BAR) domain of ArfGAP with SH3 domain, ANK repeat and PH domain containing protein 3; BAR domains are dimerization, lipid binding and curvature sensing modules found in many different proteins with diverse functions. ASAP3 (ArfGAP with SH3 domain, ANK repeat and PH domain containing protein 3) is also known as ACAP4 (ArfGAP with Coiled-coil, ANK repeat and PH domain containing protein 4), DDEFL1 (Development and Differentiation Enhancing Factor-Like 1), or centaurin beta-6. It is an Arf6-specific GTPase activating protein (GAP) and is co-localized with Arf6 in ruffling membranes upon EGF stimulation. ASAP3 is implicated in the pathogenesis of hepatocellular carcinoma and plays a role in regulating cell migration and invasion. ASAP3 contains an N-terminal BAR domain, followed by a Pleckstrin homology (PH) domain, an Arf GAP domain, ankyrin (ANK) repeats, and a C-terminal SH3 domain. BAR domains form dimers that bind to membranes, induce membrane bending and curvature, and may also be involved in protein-protein interactions. The BAR domain of the related protein ASAP1 mediates membrane bending, is essential for function, and autoinhibits GAP activity by interacting with the PH and/or Arf GAP domains.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 568931021   2 ASTLCRPMALEGDQAILQRIKKAVRAIHSSGLGHVETEEHYREAVEALGNSHLSQNSHELSTGFLNLAVFTREVAALFKN 81
Cdd:cd07640    2 STAAALEESLEGDQASLQRIKKIVKAIHNSGLNHVENEEQYTEALENLGNSHLSQNNHELSTGFLNLAVFTREVTALFKN 81

                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 568931021  82 LVQNLNNIVSFPLDSLMKGHLRDGRHDSKKHLEKAWKDYESKVAKLEKERDRARFPGG----SHGVMSQDTQRERRVFQL 157
Cdd:cd07640   82 LVQNLNNIVSFPLDSLLKGQLRDGRLESKKQMEKAWKDYEAKIGKLEKERREKQKQHGlirlDMTDTAEDMQRERRNFQL 161

                        170       180       190       200       210
                 ....*....|....*....|....*....|....*....|....*....|..
gi 568931021 158 HMCEYLVKAGESQVKQGPDFLQSLIKFFHAQHNFFQDGWKAAQSLSPFIDKL 209
Cdd:cd07640  162 HMCEYLLKAQESQMKQGPDFLQSLIKFFHAQHNFFQDGWKAAQNLGPFIEKL 213

ArfGAP domain of ASAP3 (ArfGAP with ANK repeat and PH domain-containing protein 3); The ArfGAPs are a family of multidomain proteins with a common catalytic domain that promotes the hydrolysis of GTP bound to Arf, thereby inactivating Arf signaling. ASAP-subfamily GAPs include three members: ASAP1, ASAP2, ASAP3. The ASAP subfamily comprises Arf GAP, SH3, ANK repeat and PH domains. From the N-terminus, each member has a BAR, PH, Arf GAP, ANK repeat, and proline rich domains. Unlike ASAP1 and ASAP2, ASAP3 do not have an SH3 domain at the C-terminus. ASAP1 and ASAP2 show strong GTPase-activating protein (GAP) activity toward Arf1 and Arf5 and weak activity toward Arf6. ASAP1 is a target of Src and FAK signaling that regulates focal adhesions, circular dorsal ruffles (CDR), invadopodia, and podosomes. ASAP1 GAP activity is synergistically stimulated by phosphatidylinositol 4,5-bisphosphate (PIP2) and phosphatidic acid. ASAP2 is believed to function as an ArfGAP that controls ARF-mediated vesicle budding when recruited to Golgi membranes. It also functions as a substrate and downstream target for protein tyrosine kinases Pyk2 and Src, a pathway that may be involved in the regulation of vesicular transport. ASAP3 is a focal adhesion-associated ArfGAP that functions in cell migration and invasion. Similar to ASAP1, the GAP activity of ASAP3 is strongly enhanced by PIP2 via PH domain. Like ASAP1, ASAP3 associates with focal adhesions and circular dorsal ruffles. However, unlike ASAP1, ASAP3 does not localize to invadopodia or podosomes. ASAP 1 and 3 have been implicated in oncogenesis, as ASAP1 is highly expressed in metastatic breast cancer and ASAP3 in hepatocellular carcinoma.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 568931021 389 LTNMLVAEVKSRPGNDRCCDCGAADPTWLSTNLGVLTCIQCSGVHRELGVRFSRIQSLTLDLLGPSELLLALNIGNSHFN 468
Cdd:cd17900    1 LTKLLIAEVKSRPGNSQCCDCGAPDPTWLSTNLGILTCIECSGIHRELGVRYSRIQSLTLDLLSTSELLLAVSMGNTRFN 80

                         90       100       110       120
                 ....*....|....*....|....*....|....*....|....
gi 568931021 469 EVMEAHLPSHGSPKPSAESDMSSRRNYIVAKYVEHKFARHSTPD 512
Cdd:cd17900   81 EVMEATLPAHGGPKPSAESDMGTRKDYIMAKYVEHRFVRKRCTP 124

ArfGAP domain of ASAP (Arf GAP, SH3, ANK repeat and PH domains) subfamily of ADP-ribosylation factor GTPase-activating proteins; The ArfGAPs are a family of multidomain proteins with a common catalytic domain that promotes the hydrolysis of GTP bound to Arf, thereby inactivating Arf signaling. ASAP-subfamily GAPs include three members: ASAP1, ASAP2, ASAP3. The ASAP subfamily comprises Arf GAP, SH3, ANK repeat and PH domains. From the N-terminus, each member has a BAR, PH, Arf GAP, ANK repeat, and proline rich domains. Unlike ASAP3, ASAP1 and ASAP2 also have an SH3 domain at the C-terminus. ASAP1 and ASAP2 show strong GTPase-activating protein (GAP) activity toward Arf1 and Arf5 and weak activity toward Arf6. ASAP1 is a target of Src and FAK signaling that regulates focal adhesions, circular dorsal ruffles (CDR), invadopodia, and podosomes. ASAP1 GAP activity is synergistically stimulated by phosphatidylinositol 4,5-bisphosphate (PIP2) and phosphatidic acid. ASAP2 is believed to function as an ArfGAP that controls ARF-mediated vesicle budding when recruited to Golgi membranes. It also functions as a substrate and downstream target for protein tyrosine kinases Pyk2 and Src, a pathway that may be involved in the regulation of vesicular transport. ASAP3 is a focal adhesion-associated ArfGAP that functions in cell migration and invasion. Similar to ASAP1, the GAP activity of ASAP3 is strongly enhanced by PIP2 via PH domain. Like ASAP1, ASAP3 associates with focal adhesions and circular dorsal ruffles. However, unlike ASAP1, ASAP3 does not localize to invadopodia or podosomes. Both ASAP 1 and 3 have been implicated in oncogenesis, as ASAP1 is highly expressed in metastatic breast cancer and ASAP3 in hepatocellular carcinoma.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 568931021 389 LTNMLVAEVKSRPGNDRCCDCGAADPTWLSTNLGVLTCIQCSGVHRELGVRFSRIQSLTLDLLGPSELLLALNIGNSHFN 468
Cdd:cd08834    1 LTKSIIAEVKRLPGNDVCCDCGSPDPTWLSTNLGILTCIECSGVHRELGVHVSRIQSLTLDNLGTSELLLARNLGNEGFN 80

                         90       100       110
                 ....*....|....*....|....*....|....*....
gi 568931021 469 EVMEAHLpsHGSPKPSAESDMSSRRNYIVAKYVEHKFAR 507
Cdd:cd08834   81 EIMEANL--PPGYKPTPNSDMEERKDFIRAKYVEKKFVV 117

ArfGAP domain of ASAP1 (ArfGAP with SH3 domain, ANK repeat and PH domain-containing protein 1); The ArfGAPs are a family of multidomain proteins with a common catalytic domain that promotes the hydrolysis of GTP bound to Arf, thereby inactivating Arf signaling. ASAP-subfamily GAPs include three members: ASAP1, ASAP2, ASAP3. The ASAP subfamily comprises Arf GAP, SH3, ANK repeat and PH domains. From the N-terminus, each member has a BAR, PH, Arf GAP, ANK repeat, and proline rich domains. Unlike ASAP3, ASAP1 and ASAP2 also have an SH3 domain at the C-terminus. ASAP1 and ASAP2 show strong GTPase-activating protein (GAP) activity toward Arf1 and Arf5 and weak activity toward Arf6. ASAP1 is a target of Src and FAK signaling that regulates focal adhesions, circular dorsal ruffles (CDR), invadopodia, and podosomes. ASAP1 GAP activity is synergistically stimulated by phosphatidylinositol 4,5-bisphosphate (PIP2) and phosphatidic acid. ASAP2 is believed to function as an ArfGAP that controls ARF-mediated vesicle budding when recruited to Golgi membranes. It also functions as a substrate and downstream target for protein tyrosine kinases Pyk2 and Src, a pathway that may be involved in the regulation of vesicular transport. ASAP3 is a focal adhesion-associated ArfGAP that functions in cell migration and invasion. Similar to ASAP1, the GAP activity of ASAP3 is strongly enhanced by PIP2 via PH domain. Like ASAP1, ASAP3 associates with focal adhesions and circular dorsal ruffles. However, unlike ASAP1, ASAP3 does not localize to invadopodia or podosomes. ASAP 1 and 3 have been implicated in oncogenesis, as ASAP1 is highly expressed in metastatic breast cancer and ASAP3 in hepatocellular carcinoma.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 568931021 389 LTNMLVAEVKSRPGNDRCCDCGAADPTWLSTNLGVLTCIQCSGVHRELGVRFSRIQSLTLDLLGPSELLLALNIGNSHFN 468
Cdd:cd08848    1 LTKAIIDDVQRLPGNEVCCDCGSPDPTWLSTNLGILTCIECSGIHREMGVHISRIQSLELDKLGTSELLLAKNVGNNSFN 80

                         90       100       110
                 ....*....|....*....|....*....|....*....
gi 568931021 469 EVMEAHLPShGSPKPSAESDMSSRRNYIVAKYVEHKFAR 507
Cdd:cd08848   81 DIMEGNLPS-PSPKPSPSSDMTARKEYITAKYVEHRFSR 118

ArfGAP with SH3 domain, ankyrin repeat and PH domain Pleckstrin homology (PH) domain; ASAPs (ASAP1, ASAP2, and ASAP3) function as an Arf-specific GAPs, participates in rhodopsin trafficking, is associated with tumor cell metastasis, modulates phagocytosis, promotes cell proliferation, facilitates vesicle budding, Golgi exocytosis, and regulates vesicle coat assembly via a Bin/Amphiphysin/Rvs domain. ASAPs contain an NH2-terminal BAR domain, a tandem PH domain/GAP domain, three ankyrin repeats, two proline-rich regions, and a COOH-terminal Src homology 3 (SH3) domain. PH domains have diverse functions, but in general are involved in targeting proteins to the appropriate cellular location or in the interaction with a binding partner. They share little sequence conservation, but all have a common fold, which is electrostatically polarized. Less than 10% of PH domains bind phosphoinositide phosphates (PIPs) with high affinity and specificity. PH domains are distinguished from other PIP-binding domains by their specific high-affinity binding to PIPs with two vicinal phosphate groups: PtdIns(3,4)P2, PtdIns(4,5)P2 or PtdIns(3,4,5)P3 which results in targeting some PH domain proteins to the plasma membrane. A few display strong specificity in lipid binding. Any specificity is usually determined by loop regions or insertions in the N-terminus of the domain, which are not conserved across all PH domains. PH domains are found in cellular signaling proteins such as serine/threonine kinase, tyrosine kinases, regulators of G-proteins, endocytotic GTPases, adaptors, as well as cytoskeletal associated molecules and in lipid associated enzymes.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 568931021 260 QHQGNKQFGTEKVGFLYKKSDG-IRRVWQKRKCGVKYGCLTISHSMINRPPVKLPLLTCQVRPNPEEKRCFDLVTHNRTY 338
Cdd:cd13251    1 QQQGNKSHGTEKSGYLLKKSEGkIRKVWQKRRCSIKDGFLTISHADENKPPAKLNLLTCQVKLVPEDKKCFDLISHNRTY 80

                         90       100
                 ....*....|....*....|....*...
gi 568931021 339 HFHAEDEQECEAWVSVLQNSKDEALSNA 366
Cdd:cd13251   81 HFQAEDENDANAWMSVLKNSKEQALNKA 108

GTPase-activating protein (GAP) for the ADP ribosylation factors (ARFs); ArfGAPs are a family of proteins containing an ArfGAP catalytic domain that induces the hydrolysis of GTP bound to the small guanine nucleotide-binding protein Arf, a member of the Ras superfamily of GTPases. Like all GTP-binding proteins, Arf proteins function as molecular switches, cycling between GTP (active-membrane bound) and GDP (inactive-cytosolic) form. Conversion to the GTP-bound form requires a guanine nucleotide exchange factor (GEF), whereas conversion to the GDP-bound form is catalyzed by a GTPase activating protein (GAP). In that sense, ArfGAPs were originally proposed to function as terminators of Arf signaling, which is mediated by regulating Arf family GTP-binding proteins. However, recent studies suggest that ArfGAPs can also function as Arf effectors, independently of their GAP enzymatic activity to transduce signals in cells. The ArfGAP domain contains a C4-type zinc finger motif and a conserved arginine that is required for activity, within a specific spacing (CX2CX16CX2CX4R). ArfGAPs, which have multiple functional domains, regulate the membrane trafficking and actin cytoskeleton remodeling via specific interactions with signaling lipids such as phosphoinositides and trafficking proteins, which consequently affect cellular events such as cell growth, migration, and cancer invasion. The ArfGAP family, which includes 31 human ArfGAP-domain containing proteins, is divided into 10 subfamilies based on domain structure and sequence similarity. The ArfGAP nomenclature is mainly based on the protein domain structure. For example, ASAP1 contains ArfGAP, SH3, ANK repeat and PH domains; ARAPs contain ArfGAP, Rho GAP, ANK repeat and PH domains; ACAPs contain ArfGAP, BAR (coiled coil), ANK repeat and PH domains; and AGAPs contain Arf GAP, GTP-binding protein-like, ANK repeat and PH domains. Furthermore, the ArfGAPs can be classified into two major types of subfamilies, according to the overall domain structure: the ArfGAP1 type includes 6 subfamilies (ArfGAP1, ArfGAP2/3, ADAP, SMAP, AGFG, and GIT), which contain the ArfGAP domain at the N-terminus of the protein; and the AZAP type includes 4 subfamilies (ASAP, ACAP, AGAP, and ARAP), which contain an ArfGAP domain between the PH and ANK repeat domains.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 568931021 394 VAEVKSRPGNDRCCDCGAADPTWLSTNLGVLTCIQCSGVHRELGVRFSRIQSLTLDLLGPSELLLALNIGNSHFNEVMEA 473
Cdd:cd08204    1 LEELLKLPGNKVCADCGAPDPRWASINLGVFICIRCSGIHRSLGVHISKVRSLTLDSWTPEQVELMKAIGNARANAYYEA 80

                         90       100
                 ....*....|....*....|....*..
gi 568931021 474 HLPShGSPKPSAESDMSSRRNYIVAKY 500
Cdd:cd08204   81 NLPP-GFKKPTPDSSDEEREQFIRAKY 106

ArfGAP domain of ACAP3 (ArfGAP with Coiled-coil, ANK repeat and PH domains 3); ACAP3 belongs to the ACAP subfamily of GAPs (GTPase-activating proteins) for the small GTPase Arf (ADP-ribosylation factor). ACAP subfamily of ArfGAPs are composed of Coiled coli (BAR, Bin-Amphiphysin-Rvs), PH, ArfGAP and ANK repeats domains. It has been shown that ACAP3 positively regulates neurite outgrowth through its GAP activity specific to Arf6 in mouse hippocampal neurons. ACAP1 (centaurin beta1) and ACAP2 centaurin beta2) also have a GAP (GTPase-activating protein) activity preferentially toward Arf6, which regulates endocytic recycling. Both ACAP1/2 are activated by are activated by the phosphoinositides, PI(4,5)P2 and PI(3,5)P2. ACAP1 binds specifically with recycling cargo proteins such as transferrin receptor (TfR) and cellubrevin. Thus, ACAP1 promotes cargo sorting to enhance TfR recycling from the recycling endosome. In addition, phosphorylation of ACAP by Akt, a serine/threonine protein kinase, regulates the recycling of integrin beta1 to control cell migration. In contrast, ACAP2 does not exhibit a similar interaction with the recycling cargo proteins. It has been shown that ACAP2 functions both as an effector of Ras-related protein Rab35 and as an Arf6-GTPase-activating protein (GAP) during neurite outgrowth of PC12 cells. Moreover, ACAP2, together with Rab35, regulates phagocytosis in mammalian macrophages.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 568931021 393 LVAEVKSRPGNDRCCDCGAADPTWLSTNLGVLTCIQCSGVHRELGVRFSRIQSLTLDLLGPSELLLALNIGNSHFNEVME 472
Cdd:cd08850    3 ILQRVQSIAGNDQCCDCGQPDPRWASINLGILLCIECSGIHRSLGVHCSKVRSLTLDSWEPELLKLMCELGNSTVNQIYE 82

                         90       100       110
                 ....*....|....*....|....*....|...
gi 568931021 473 AHLPSHGSPKPSAESDMSSRRNYIVAKYVEHKF 505
Cdd:cd08850   83 AQCEELGLKKPTASSSRQDKEAWIKAKYVEKKF 115

ArfGAP domain of ACAP2 (ArfGAP with Coiled-coil, ANK repeat and PH domains 2); ACAP2 belongs to the ACAP subfamily of GAPs (GTPase-activating proteins) for the small GTPase Arf (ADP-ribosylation factor). ACAP subfamily of ArfGAPs are composed of Coiled coli (BAR, Bin-Amphiphysin-Rvs), PH, ArfGAP and ANK repeats domains. ACAP1 (centaurin beta1) and ACAP2 centaurin beta2) have a GAP (GTPase-activating protein) activity preferentially toward Arf6, which regulates endocytic recycling. Both ACAP1/2 are activated by are activated by the phosphoinositides, PI(4,5)P2 and PI(3,5)P2. ACAP1 binds specifically with recycling cargo proteins such as transferrin receptor (TfR) and cellubrevin. Thus, ACAP1 promotes cargo sorting to enhance TfR recycling from the recycling endosome. In addition, phosphorylation of ACAP by Akt, a serine/threonine protein kinase, regulates the recycling of integrin beta1 to control cell migration. In contrast, ACAP2 does not exhibit a similar interaction with the recycling cargo proteins. It has been shown that ACAP2 functions both as an effector of Ras-related protein Rab35 and as an Arf6-GTPase-activating protein (GAP) during neurite outgrowth of PC12 cells. Moreover, ACAP2, together with Rab35, regulates phagocytosis in mammalian macrophages. ACAP3 also positively regulates neurite outgrowth through its GAP activity specific to Arf6 in mouse hippocampal neurons.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 568931021 397 VKSRPGNDRCCDCGAADPTWLSTNLGVLTCIQCSGVHRELGVRFSRIQSLTLDLLGPSELLLALNIGNSHFNEVMEAHLP 476
Cdd:cd08851    7 VQCIPGNASCCDCGLADPRWASINLGITLCIECSGIHRSLGVHFSKVRSLTLDTWEPELLKLMCELGNDVINRIYEARVE 86

                         90       100
                 ....*....|....*....|....*....
gi 568931021 477 SHGSPKPSAESDMSSRRNYIVAKYVEHKF 505
Cdd:cd08851   87 KMGAKKPQPGGQRQEKEAYIRAKYVERKF 115

ArfGAP with GTPase domain, ANK repeat and PH domains; The AGAP subfamily of ADP-ribosylation factor GTPase-activating proteins (Arf GAPs) includes three members: AGAP1-3. In addition to the Arf GAP domain, AGAP proteins contain GTP-binding protein-like, ANK repeat and pleckstrin homology (PH) domains. AGAP1 and AGAP2 have phosphatidylinositol 4,5-bisphosphate (PI(4,5)P2)-mediated GTPase-activating protein (GAP) activity preferentially toward Arf1, and function in the endocytic system. AGAP1 and AGAP2 independently regulate AP-3 endosomes and AP-1/Rab4 fast recycling endosomes, respectively. AGAP1, via its PH domain, directly interacts with the adapter protein 3 (AP-3), which is a coat protein involved in trafficking in the endosomal-lysosomal system, and regulates AP-3-dependent trafficking. In other hand, AGAP2 specifically binds the clathrin adaptor protein AP-1 and regulates the AP-1/Rab-4 dependent endosomal trafficking. AGAP2 is overexpressed in different human cancers including prostate carcinoma and glioblastoma, and promotes cancer cell invasion. AGAP3 exists as a component of the NMDA receptor complex that regulates Arf6 and Ras/ERK signaling pathways. Moreover, AGAP3 regulates AMPA receptor trafficking through the ArfGAP domain. Together, AGAP3 is believed to involve in linking NMDA receptor activation to AMPA receptor trafficking.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 568931021 392 MLVAEVKSRPGNDRCCDCGAADPTWLSTNLGVLTCIQCSGVHRELGVRFSRIQSLTLDLLgPSELL-LALNIGNSHFNEV 470
Cdd:cd08836    1 AALQAIRNVRGNDHCVDCGAPNPDWASLNLGALMCIECSGIHRNLGTHISRVRSLDLDDW-PVELLkVMSAIGNDLANSV 79

                         90       100       110
                 ....*....|....*....|....*....|.
gi 568931021 471 MEAHLPSHgsPKPSAESDMSSRRNYIVAKYV 501
Cdd:cd08836   80 WEGNTQGR--TKPTPDSSREEKERWIRAKYE 108

ArfGAP with GTPase domain, ANK repeat and PH domain 1; The AGAP subfamily of ADP-ribosylation factor GTPase-activating proteins (Arf GAPs) includes three members: AGAP1-3. In addition to the Arf GAP domain, AGAP proteins contain GTP-binding protein-like, ANK repeat and pleckstrin homology (PH) domains. AGAP1 and AGAP2 have phosphatidylinositol 4,5-bisphosphate (PI(4,5)P2)-mediated GTPase-activating protein (GAP) activity preferentially toward Arf1, and function in the endocytic system. AGAP1 and AGAP2 independently regulate AP-3 endosomes and AP-1/Rab4 fast recycling endosomes, respectively. AGAP1, via its PH domain, directly interacts with the adapter protein 3 (AP-3), which is a coat protein involved in trafficking in the endosomal-lysosomal system, and regulates AP-3-dependent trafficking. In other hand, AGAP2 specifically binds the clathrin adaptor protein AP-1 and regulates the AP-1/Rab-4 dependent endosomal trafficking. AGAP2 is overexpressed in different human cancers including prostate carcinoma and glioblastoma, and promotes cancer cell invasion. AGAP3 exists as a component of the NMDA receptor complex that regulates Arf6 and Ras/ERK signaling pathways. Moreover, AGAP3 regulates AMPA receptor trafficking through the ArfGAP domain. Together, AGAP3 is believed to involve in linking NMDA receptor activation to AMPA receptor trafficking.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 568931021 397 VKSRPGNDRCCDCGAADPTWLSTNLGVLTCIQCSGVHRELGVRFSRIQSLTLDLLgPSELLLALN-IGNSHFNEVMEAHl 475
Cdd:cd08854    7 IRNAKGNSLCVDCGAPNPTWASLNLGALICIECSGIHRNLGTHLSRVRSLDLDDW-PRELTLVLTaIGNHMANSIWESC- 84

                         90       100
                 ....*....|....*....|....*
gi 568931021 476 pSHGSPKPSAESDMSSRRNYIVAKY 500
Cdd:cd08854   85 -TQGRTKPAPDSSREERESWIRAKY 108

ArfGap with dual PH domains; The ADAP subfamily, ArfGAPs with dual pleckstrin homology (PH) domains, includes two members: ADAP1 and ADAP2. Both ADAP1 (also known as centaurin-alpha1, p42(IP4), or PIP3BP) and ADAP2 (centaurin-alpha2) display a GTPase-activating protein (GAP) activity toward Arf6 (ADP-ribosylation factor 6), which is involved in protein trafficking that regulates endocytic recycling, cytoskeleton remodeling, and neuronal differentiation. ADAP2 has high sequence similarity to the ADAP1 and they both contain a ArfGAP domain at the N-terminus, followed by two PH domains. However, ADAP1, unlike ADAP2, contains a putative N-terminal nuclear localization signal. The PH domains of ADAP1bind to the two second messenger molecules phosphatidylinositol 3,4,5-trisphosphate (PI(3,4,5)P3) and inositol 1,3,4,5-tetrakisphosphate (I(1,3,4,5)P4) with identical high affinity, whereas those of ADAP2 specifically binds phosphatidylinositol 3,4-bisphosphate (PI(3,4)P2) and PI(3,4,5)P3, which are produced by activated phosphatidylinositol 3-kinase. ADAP1 is predominantly expressed in the brain neurons, while ADAP2 is broadly expressed, including the adipocytes, heart, and skeletal muscle but not in the brain. The limited distribution and high expression of ADAP1 in the brain indicates that ADAP1 is important for neuronal functions. ADAP1 has been shown to highly expressed in the neurons and plagues of Alzheimer's disease patients. In other hand, ADAP2 gene deletion has been shown to cause circulatory deficiencies and heart shape defects in zebrafish, indicating that ADAP2 has a vital role in heart development. Taken together, the hemizygous deletion of ADAP2 gene may be contributing to the cardiovascular malformation in patients with neurofibromatosis type 1 (NF1) microdeletions.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 568931021 394 VAEVKSRPGNDRCCDCGAADPTWLSTNLGVLTCIQCSGVHRELGVRFSRIQSLTLDLLGPSELLLALNIGNSHFNEVMEA 473
Cdd:cd08832    8 LLELLKLPGNNTCADCGAPDPEWASYNLGVFICLDCSGIHRSLGTHISKVKSLRLDNWDDSQVEFMEENGNEKAKAKYEA 87

                         90       100
                 ....*....|....*....|....*..
gi 568931021 474 HLPShGSPKPSAESDMSSRRNYIVAKY 500
Cdd:cd08832   88 HVPA-FYRRPTPTDPQVLREQWIRAKY 113

ArfGap with Rho-Gap domain, ANK repeat and PH domain-containing proteins; The ARAP subfamily includes three members, ARAP1-3, and belongs to the ADP-ribosylation factor GTPase-activating proteins (Arf GAPs) family of proteins that promotes the hydrolysis of GTP bound to Arf, thereby inactivating Arf signaling. The function of Arfs is dependent on GAPs and guanine nucleotide exchange factors (GEFs), which allow Arfs to cycle between the GDP-bound and GTP-bound forms. In addition to the Arf GAP domain, ARAPs contain the SAM (sterile-alpha motif) domain, 5 pleckstrin homology (PH) domains, the Rho-GAP domain, the Ras-association domain, and ANK repeats. ARAPs show phosphatidylinositol 3,4,5-trisphosphate (PI(3,4,5)P3)-dependent GAP activity toward Arf6. ARAPs play important roles in endocytic trafficking, cytoskeleton reorganization in response to growth factors stimulation, and focal adhesion dynamics.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 568931021 391 NMLVAEVKSRPGNDRCCDCGAADPTWLSTNLGVLTCIQCSGVHRELGVRFSRIQSLTLDLLGPSELL--LALNIGNSHFN 468
Cdd:cd08837    1 YEVAEKIWSNPANRFCADCGAPDPDWASINLCVVICKQCAGEHRSLGSNISKVRSLKMDTKVWTEELveLFLKLGNDRAN 80

                         90       100       110
                 ....*....|....*....|....*....|....*..
gi 568931021 469 EVMEAHLPSHGSPKPSaeSDMSSRRNYIVAKYVEHKF 505
Cdd:cd08837   81 RFWAANLPPSEALHPD--ADSEQRREFITAKYREGKY 115

Arf1 GTPase-activating protein 1; ArfGAP (ADP Ribosylation Factor GTPase Activating Protein) domain is a part of ArfGap1-like proteins that play a crucial role in controlling of membrane trafficking, particularly in the formation of COPI (coat protein complex I)-coated vesicles on Golgi membranes. The ArfGAP1 protein subfamily consists of three members: ArfGAP1 (Gcs1p in yeast), ArfGAP2 and ArfGAP3 (both are homologs of yeast Glo3p). ArfGAP2/3 are closely related, but with little similarity to ArfGAP1, except the catalytic ArfGAP domain. They promote hydrolysis of GTP bound to the small G protein ADP-ribosylation factor 1 (Arf1), which leads to the dissociation of coat proteins from Golgi-derived membranes and vesicles. Dissociation of the coat proteins is required for the fusion of these vesicles with target compartments. Thus, the GAP catalytic activity plays a key role in the formation of COPI vesicles from Golgi membrane. In contrast to ArfGAP1, which displays membrane curvature-dependent ArfGAP activity, ArfGAP2 and ArfGAP3 activities are dependent on coatomer (the core COPI complex) which required for efficient recruitment of ArfGAP2 and ArfGAP3 to the Golgi membrane. Accordingly, ArfGAP2/3 has been implicated in coatomer-mediated protein transport between the Golgi complex and the endoplasmic reticulum. Unlike ArfGAP1, which is controlled by membrane curvature through its amphipathic lipid packing sensor (ALPS) motifs, ArfGAP2/3 do not possess ALPS motif.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 568931021 395 AEVKSRPGNDRCCDCGAADPTWLSTNLGVLTCIQCSGVHRELGVRFSRIQSLTLDLLGPSELLLALNIGNSHFNEVMEAH 474
Cdd:cd08830    6 RELQKLPGNNRCFDCGAPNPQWASVSYGIFICLECSGVHRGLGVHISFVRSITMDSWSEKQLKKMELGGNAKLREFFESY 85

                 ....*..
gi 568931021 475 LPSHGSP 481
Cdd:cd08830   86 GISPDLP 92

Arf1 GTPase-activating protein 2/3-like; ArfGAP (ADP Ribosylation Factor GTPase Activating Protein) domain is a part of ArfGap1-like proteins that play a crucial role in controlling of membrane trafficking, particularly in the formation of COPI (coat protein complex I)-coated vesicles on Golgi membranes. The ArfGAP1 protein subfamily consists of three members: ArfGAP1 (Gcs1p in yeast), ArfGAP2 and ArfGAP3 (both are homologs of yeast Glo3p). ArfGAP2/3 are closely related, but with little similarity to ArfGAP1, except the catalytic ArfGAP domain. They promote hydrolysis of GTP bound to the small G protein ADP-ribosylation factor 1 (Arf1), which leads to the dissociation of coat proteins from Golgi-derived membranes and vesicles. Dissociation of the coat proteins is required for the fusion of these vesicles with target compartments. Thus, the GAP catalytic activity plays a key role in the formation of COPI vesicles from Golgi membrane. In contrast to ArfGAP1, which displays membrane curvature-dependent ArfGAP activity, ArfGAP2 and ArfGAP3 activities are dependent on coatomer (the core COPI complex) which required for efficient recruitment of ArfGAP2 and ArfGAP3 to the Golgi membrane. Accordingly, ArfGAP2/3 has been implicated in coatomer-mediated protein transport between the Golgi complex and the endoplasmic reticulum. Unlike ArfGAP1, which is controlled by membrane curvature through its amphipathic lipid packing sensor (ALPS) motifs, ArfGAP2/3 do not possess ALPS motif.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 568931021 393 LVAEVKSRPGNDRCCDCGAADPTWLSTNLGVLTCIQCSGVHRELGVRFSRIQSLTLDLLGPSELLLALNIGNSHFNEVME 472
Cdd:cd08831    5 IFKKLRSKPENKVCFDCGAKNPTWASVTFGVFLCLDCSGVHRSLGVHISFVRSTNLDSWTPEQLRRMKVGGNAKAREFFK 84

                 ..
gi 568931021 473 AH 474
Cdd:cd08831   85 QH 86

ArfGap with Rho-Gap domain, ANK repeat and PH domain-containing protein 3; The ARAP subfamily includes three members, ARAP1-3, and belongs to the ADP-ribosylation factor GTPase-activating proteins (Arf GAPs) family of proteins that promotes the hydrolysis of GTP bound to Arf, thereby inactivating Arf signaling. The function of Arfs is dependent on GAPs and guanine nucleotide exchange factors (GEFs), which allow Arfs to cycle between the GDP-bound and GTP-bound forms. In addition to the Arf GAP domain, ARAPs contain the SAM (sterile-alpha motif) domain, 5 pleckstrin homology (PH) domains, the Rho-GAP domain, the Ras-association domain, and ANK repeats. ARAPs show phosphatidylinositol 3,4,5-trisphosphate (PI(3,4,5)P3)-dependent GAP activity toward Arf6. ARAPs play important roles in endocytic trafficking, cytoskeleton reorganization in response to growth factors stimulation, and focal adhesion dynamics. ARAP3 possesses a unique dual-specificity GAP activity for Arf6 and RhoA regulated by PI(3,4,5)P3 and a small GTPase Rap1-GTP. The RhoGAP activity of ARAP3 is enhanced by direct binding of Rap1-GTP to the Ras-association (RA) domain. ARAP3 is involved in regulation of cell shape and adhesion.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 568931021 394 VAE-VKSRPGNDRCCDCGAADPTWLSTNLGVLTCIQCSGVHRELGVRFSRIQSLTLDLLGPSELLLALNI--GNSHFNEV 470
Cdd:cd17902    3 VAEkIWSNKANRFCADCHASSPDWASINLCVVICKQCAGQHRSLGSGISKVQSLKLDTSVWSNEIVQLFIvlGNDRANRF 82

                         90       100       110
                 ....*....|....*....|....*....|....*
gi 568931021 471 MEAHLPSHGSPKPSAESDmsSRRNYIVAKYVEHKF 505
Cdd:cd17902   83 WAARLPASEALHPDATPE--QRREFISRKYREGRF 115

ArfGap with Rho-Gap domain, ANK repeat and PH domain-containing protein 2; The ARAP subfamily includes three members, ARAP1-3, and belongs to the ADP-ribosylation factor GTPase-activating proteins (Arf GAPs) family of proteins that promotes the hydrolysis of GTP bound to Arf, thereby inactivating Arf signaling. The function of Arfs is dependent on GAPs and guanine nucleotide exchange factors (GEFs), which allow Arfs to cycle between the GDP-bound and GTP-bound forms. In addition to the Arf GAP domain, ARAPs contain the SAM (sterile-alpha motif) domain, 5 pleckstrin homology (PH) domains, the Rho-GAP domain, the Ras-association domain, and ANK repeats. ARAPs show phosphatidylinositol 3,4,5-trisphosphate (PI(3,4,5)P3)-dependent GAP activity toward Arf6. ARAPs play important roles in endocytic trafficking, cytoskeleton reorganization in response to growth factors stimulation, and focal adhesion dynamics. ARAP2 localizes to the cell periphery and on focal adhesions composed of paxillin and vinculin, and functions downstream of RhoA to regulate focal adhesion dynamics. ARAP2 is a PI(3,4,5)P3-dependent Arf6 GAP that binds RhoA-GTP, but it lacks the predicted catalytic arginine in the RhoGAP domain and does not have RhoGAP activity. ARAP2 reduces Rac1oGTP levels by reducing Arf6oGTP levels through GAP activity. AGAP2 also binds to and regulates focal adhesion kinase (FAK). Thus, ARAP2 signals through Arf6 and Rac1 to control focal adhesion morphology.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 568931021 403 NDRCCDCGAADPTWLSTNLGVLTCIQCSGVHRELGVRFSRIQSLTLDL-LGPSELL-LALNIGNSHFNEVMEAHLPShgS 480
Cdd:cd08856   18 NRSCADCKAPDPDWASINLCVVICKKCAGQHRSLGPKDSKVRSLKMDAsIWSNELIeLFIVVGNKPANLFWAANLFS--E 95

                         90       100
                 ....*....|....*....|....*
gi 568931021 481 PKPSAESDMSSRRNYIVAKYVEHKF 505
Cdd:cd08856   96 EDLHMDSDVEQRTPFITQKYKEGKF 120

ADAP1 GTPase activating protein for Arf, with dual PH domains; The ADAP subfamily, ArfGAPs with dual pleckstrin homology (PH) domains, includes two members: ADAP1 and ADAP2. Both ADAP1 (also known as centaurin-alpha1, p42(IP4), or PIP3BP) and ADAP2 (centaurin-alpha2) display a GTPase-activating protein (GAP) activity toward Arf6 (ADP-ribosylation factor 6), which is involved in protein trafficking that regulates endocytic recycling, cytoskeleton remodeling, and neuronal differentiation. ADAP2 has high sequence similarity to the ADAP1 and they both contain a ArfGAP domain at the N-terminus, followed by two PH domains. However, ADAP1, unlike ADAP2, contains a putative N-terminal nuclear localization signal. The PH domains of ADAP1bind to the two second messenger molecules phosphatidylinositol 3,4,5-trisphosphate (PI(3,4,5)P3) and inositol 1,3,4,5-tetrakisphosphate (I(1,3,4,5)P4) with identical high affinity, whereas those of ADAP2 specifically binds phosphatidylinositol 3,4-bisphosphate (PI(3,4)P2) and PI(3,4,5)P3, which are produced by activated phosphatidylinositol 3-kinase. ADAP1 is predominantly expressed in the brain neurons, while ADAP2 is broadly expressed, including the adipocytes, heart, and skeletal muscle but not in the brain. The limited distribution and high expression of ADAP1 in the brain indicates that ADAP1 is important for neuronal functions. ADAP1 has been shown to highly expressed in the neurons and plagues of Alzheimer's disease patients. In other hand, ADAP2 gene deletion has been shown to cause circulatory deficiencies and heart shape defects in zebrafish, indicating that ADAP2 has a vital role in heart development. Taken together, the hemizygous deletion of ADAP2 gene may be contributing to the cardiovascular malformation in patients with neurofibromatosis type 1 (NF1) microdeletions.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 568931021 394 VAEVKSRPGNDRCCDCGAADPTWLSTNLGVLTCIQCSGVHRELGvRFSRIQSLTLDLLGPSELLLALNIGNSHFNEVMEA 473
Cdd:cd08843    8 VLELLQRPGNARCADCGAPDPDWASYTLGVFICLSCSGIHRNIP-QVSKVKSVRLDAWEEAQVEFMASHGNDAARARFES 86

                         90       100
                 ....*....|....*....|....*..
gi 568931021 474 HLPSHgSPKPSAESDMSSRRNYIVAKY 500
Cdd:cd08843   87 KVPSF-YYRPTPSDCQLLREQWIRAKY 112