The Bin/Amphiphysin/Rvs (BAR) domain, a dimerization module that binds membranes and detects membrane curvature; BAR domains are dimerization, lipid binding and curvature sensing modules found in many different proteins with diverse functions including organelle biogenesis, membrane trafficking or remodeling, and cell division and migration. Mutations in BAR containing proteins have been linked to diseases and their inactivation in cells leads to altered membrane dynamics. A BAR domain with an additional N-terminal amphipathic helix (an N-BAR) can drive membrane curvature. These N-BAR domains are found in amphiphysins and endophilins, among others. BAR domains are also frequently found alongside domains that determine lipid specificity, such as the Pleckstrin Homology (PH) and Phox Homology (PX) domains which are present in beta centaurins (ACAPs and ASAPs) and sorting nexins, respectively. A FES-CIP4 Homology (FCH) domain together with a coiled coil region is called the F-BAR domain and is present in Pombe/Cdc15 homology (PCH) family proteins, which include Fes/Fes tyrosine kinases, PACSIN or syndapin, CIP4-like proteins, and srGAPs, among others. The Inverse (I)-BAR or IRSp53/MIM homology Domain (IMD) is found in multi-domain proteins, such as IRSp53 and MIM, that act as scaffolding proteins and transducers of a variety of signaling pathways that link membrane dynamics and the underlying actin cytoskeleton. BAR domains form dimers that bind to membranes, induce membrane bending and curvature, and may also be involved in protein-protein interactions. The I-BAR domain induces membrane protrusions in the opposite direction compared to classical BAR and F-BAR domains, which produce membrane invaginations. BAR domains that also serve as protein interaction domains include those of arfaptin and OPHN1-like proteins, among others, which bind to Rac and Rho GAP domains, respectively.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217342963   1 MIDTGKAFCVANKQFMNGIRDLAQYSSNDAVVETSLTKFSDSLQEMINFHTrqglplslrlecrgmiiallwesshlrmI 80
Cdd:cd07638    28 MIDAGKAFCQANKQFMNGIRDLAQYSSKDAVIETSLTKFSDTLQEMINYHT----------------------------I 79

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217342963  81 LFDQTQRSIKAQLQNFVKEDLRKFKDAKKQFEKVSEEKENALVKNAQVQRNKQHEVEEATNILTATRKCFRHIALDYVLQ 160
Cdd:cd07638    80 LFDQAQRSIKAQLQTFVKEDLRKFKDAKKQFDKVSEEKENALVKNAQVQRNKQHEVEEATNILTATRKCFRHIALDYVLQ 159

                         170       180       190       200
                  ....*....|....*....|....*....|....*....|.
gi 2217342963 161 INVLQSKRRSEILKSMLSFMYAHLAFFHQGYDLFSELGPYM 201
Cdd:cd07638   160 INVLQSKRRSEILKSMLSFMYAHLTFFHQGYDLFSELGPYM 200

ArfGAP with coiled-coil, ankyrin repeat and PH domains Pleckstrin homology (PH) domain; ACAP (also called centaurin beta) functions both as a Rab35 effector and as an Arf6-GTPase-activating protein (GAP) by which it controls actin remodeling and membrane trafficking. ACAP contain an NH2-terminal bin/amphiphysin/Rvs (BAR) domain, a phospholipid-binding domain, a PH domain, a GAP domain, and four ankyrin repeats. The AZAPs constitute a family of Arf GAPs that are characterized by an NH2-terminal pleckstrin homology (PH) domain and a central Arf GAP domain followed by two or more ankyrin repeats. On the basis of sequence and domain organization, the AZAP family is further subdivided into four subfamilies: 1) the ACAPs contain an NH2-terminal bin/amphiphysin/Rvs (BAR) domain (a phospholipid-binding domain that is thought to sense membrane curvature), a single PH domain followed by the GAP domain, and four ankyrin repeats; 2) the ASAPs also contain an NH2-terminal BAR domain, the tandem PH domain/GAP domain, three ankyrin repeats, two proline-rich regions, and a COOH-terminal Src homology 3 domain; 3) the AGAPs contain an NH2-terminal GTPase-like domain (GLD), a split PH domain, and the GAP domain followed by four ankyrin repeats; and 4) the ARAPs contain both an Arf GAP domain and a Rho GAP domain, as well as an NH2-terminal sterile-a motif (SAM), a proline-rich region, a GTPase-binding domain, and five PH domains. PMID 18003747 and 19055940 Centaurin can bind to phosphatidlyinositol (3,4,5)P3. 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 2217342963 253 MEGYLFKRASNAFKTWNRRWFSIQNNQLVYQKKF-KDNPTVVVEDLRLCTVKHCEDIERRFCFEVVSPTKSCMLQADSEK 331
Cdd:cd13250     1 KEGYLFKRSSNAFKTWKRRWFSLQNGQLYYQKRDkKDEPTVMVEDLRLCTVKPTEDSDRRFCFEVISPTKSYMLQAESEE 80

                          90
                  ....*....|....*...
gi 2217342963 332 LRQAWIKAVQTSIATAYR 349
Cdd:cd13250    81 DRQAWIQAIQSAIASALN 98

The Bin/Amphiphysin/Rvs (BAR) domain of ArfGAP with Coiled-coil, ANK repeat and PH domain containing protein 2; BAR domains are dimerization, lipid binding and curvature sensing modules found in many different proteins with diverse functions. ACAP2 (ArfGAP with Coiled-coil, ANK repeat and PH domain containing protein 2), also called centaurin beta-2, is an Arf6-specific GTPase activating protein (GAP) which mediates Arf6 signaling. Arf6 is involved in the regulation of endocytosis, phagocytosis, cell adhesion and migration. ACAP2 contains an N-terminal BAR domain, followed by a Pleckstrin homology (PH) domain, an Arf GAP domain, and C-terminal ankyrin (ANK) repeats. BAR domains form dimers that bind to membranes, induce membrane bending and curvature, and may also be involved in protein-protein interactions.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217342963   1 MIDTGKAFCVANKQFMNGIRDLAQYSSNDAVVETSLTKFSDSLQEMINFHTrqglplslrlecrgmiiallwesshlrmI 80
Cdd:cd07638    28 MIDAGKAFCQANKQFMNGIRDLAQYSSKDAVIETSLTKFSDTLQEMINYHT----------------------------I 79

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217342963  81 LFDQTQRSIKAQLQNFVKEDLRKFKDAKKQFEKVSEEKENALVKNAQVQRNKQHEVEEATNILTATRKCFRHIALDYVLQ 160
Cdd:cd07638    80 LFDQAQRSIKAQLQTFVKEDLRKFKDAKKQFDKVSEEKENALVKNAQVQRNKQHEVEEATNILTATRKCFRHIALDYVLQ 159

                         170       180       190       200
                  ....*....|....*....|....*....|....*....|.
gi 2217342963 161 INVLQSKRRSEILKSMLSFMYAHLAFFHQGYDLFSELGPYM 201
Cdd:cd07638   160 INVLQSKRRSEILKSMLSFMYAHLTFFHQGYDLFSELGPYM 200

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 2217342963   1 MIDTGKAFCVANKQFMNGIRDLAQYSSNDAVVETSLTKFSDSLQEMINFHTrqglplslrlecrgmiiallwesshlrmI 80
Cdd:pfam16746  41 MIEAGKEYSAAQRLFANSLLDFKFEFIGDEETDESLKKFSQLLQEMENFHT----------------------------I 92

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217342963  81 LFDQTQRSIKAQLQNFVKEDLRKFKDAKKQFEKVSEEKENALVKNAQVQRNK-QHEVEEATNILTATRKCFRHIALDYVL 159
Cdd:pfam16746  93 LLDQAQRTIIKPLENFRKEDLKEVKELKKKFDKASEKLDAALEKNAQLSKKKkPSELEEADNELAATRKCFHHASLDYVL 172

                         170       180       190       200       210       220
                  ....*....|....*....|....*....|....*....|....*....|....*....|...
gi 2217342963 160 QINVLQSKRRSEILKSMLSFMYAHLAFFHQGYDLFSELGPYMKDLGAQLDRLVVDAAKEKREM 222
Cdd:pfam16746 173 QINELQERKKFEILEPLLSFMHAQFTFFHQGYELFKDLEPFMKDLQAQLQQTREDTREEKEEL 235

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 2217342963  386 LQRVQCIPGNASCCDCGLADPRWASINLGITLCIECSGIHRSLGVHFSKVRSLTLDTWEPELLKLMCELGNDVINRVYEA 465
Cdd:smart00105   1 LKLLRSIPGNKKCFDCGAPNPTWASVNLGVFLCIECSGIHRSLGVHISKVRSLTLDTWTEEELRLLQKGGNENANSIWES 80

                           90       100       110
                   ....*....|....*....|....*....|....*.
gi 2217342963  466 NVEKMGIKKPQPGQRQEKEAYIRAKYVERKFVDKYS 501
Cdd:smart00105  81 NLDDFSLKPPDDDDQQKYESFIAAKYEEKLFVPPES 116

GTPase-activating protein that regulates ARFs (ADP-ribosylation factors), involved in ARF-mediated vesicular transport [Intracellular trafficking and secretion];

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217342963 371 SGNESKEKLLKgesALQRvqcIPGNASCCDCGLADPRWASINLGITLCIECSGIHRSLGVHFSKVRSLTLDTWEPELLKL 450
Cdd:COG5347     2 STKSEDRKLLK---LLKS---DSSNKKCADCGAPNPTWASVNLGVFLCIDCAGVHRSLGVHISKVKSLTLDNWTEEELRR 75

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217342963 451 MCELGNDVINRVYEANvekmGIKKPQPGQR-----QEKEAYIRAKYVERKFVD---KYSISLSPPEQQKKFVSKSSEEKR 522
Cdd:COG5347    76 MEVGGNSNANRFYEKN----LLDQLLLPIKakydsSVAKKYIRKKYELKKFIDdssSPSDFSSFSASSTRTVDSVDDRLD 151

                         170       180       190       200
                  ....*....|....*....|....*....|....*....|.
gi 2217342963 523 LSISKFGPGDQVRASAQSSVRSNDSGIQQSSDDGRESLPST 563
Cdd:COG5347   152 SESQSRSSSASLGNSNRPDDELNVESFQSTGSKPRSLTSTK 192

Pleckstrin homology domain; Domain commonly found in eukaryotic signalling proteins. The domain family possesses multiple functions including the abilities to bind inositol phosphates, and various proteins. PH domains have been found to possess inserted domains (such as in PLC gamma, syntrophins) and to be inserted within other domains. Mutations in Brutons tyrosine kinase (Btk) within its PH domain cause X-linked agammaglobulinaemia (XLA) in patients. Point mutations cluster into the positively charged end of the molecule around the predicted binding site for phosphatidylinositol lipids.

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217342963  251 IVMEGYLFKRASNAFKTWNRRWFSIQNNQLVYQKKFKDNPTVVVE---DLRLCTVKHCEDI---ERRFCFEVVSPTKSCM 324
Cdd:smart00233   1 VIKEGWLYKKSGGGKKSWKKRYFVLFNSTLLYYKSKKDKKSYKPKgsiDLSGCTVREAPDPdssKKPHCFEIKTSDRKTL 80

                           90       100
                   ....*....|....*....|..
gi 2217342963  325 -LQADSEKLRQAWIKAVQTSIA 345
Cdd:smart00233  81 lLQAESEEEREKWVEALRKAIA 102

PH domain; PH stands for pleckstrin homology.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217342963 251 IVMEGYLFKRASNAFKTWNRRWFSIQNNQLVYQK----KFKDNPTVVVeDLRLCTVKHCEDIE---RRFCFEVVSPTKSC 323
Cdd:pfam00169   1 VVKEGWLLKKGGGKKKSWKKRYFVLFDGSLLYYKddksGKSKEPKGSI-SLSGCEVVEVVASDspkRKFCFELRTGERTG 79

                          90       100
                  ....*....|....*....|....*.
gi 2217342963 324 M----LQADSEKLRQAWIKAVQTSIA 345
Cdd:pfam00169  80 KrtylLQAESEEERKDWIKAIQSAIR 105

Ankyrin repeats (3 copies);

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217342963 629 LIQAVLGGSLVTCEFLLQNGANVNQRDVQGRGPLHHATVLGHTgQVCLFLKRGANQHATDeEGKDPLSIAVEAANADIVT 708
Cdd:pfam12796   1 LHLAAKNGNLELVKLLLENGADANLQDKNGRTALHLAAKNGHL-EIVKLLLEHADVNLKD-NGRTALHYAARSGHLEIVK 78

                  ..
gi 2217342963 709 LL 710
Cdd:pfam12796  79 LL 80

The Bin/Amphiphysin/Rvs (BAR) domain of ArfGAP with Coiled-coil, ANK repeat and PH domain containing protein 2; BAR domains are dimerization, lipid binding and curvature sensing modules found in many different proteins with diverse functions. ACAP2 (ArfGAP with Coiled-coil, ANK repeat and PH domain containing protein 2), also called centaurin beta-2, is an Arf6-specific GTPase activating protein (GAP) which mediates Arf6 signaling. Arf6 is involved in the regulation of endocytosis, phagocytosis, cell adhesion and migration. ACAP2 contains an N-terminal BAR domain, followed by a Pleckstrin homology (PH) domain, an Arf GAP domain, and C-terminal ankyrin (ANK) repeats. BAR domains form dimers that bind to membranes, induce membrane bending and curvature, and may also be involved in protein-protein interactions.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217342963   1 MIDTGKAFCVANKQFMNGIRDLAQYSSNDAVVETSLTKFSDSLQEMINFHTrqglplslrlecrgmiiallwesshlrmI 80
Cdd:cd07638    28 MIDAGKAFCQANKQFMNGIRDLAQYSSKDAVIETSLTKFSDTLQEMINYHT----------------------------I 79

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217342963  81 LFDQTQRSIKAQLQNFVKEDLRKFKDAKKQFEKVSEEKENALVKNAQVQRNKQHEVEEATNILTATRKCFRHIALDYVLQ 160
Cdd:cd07638    80 LFDQAQRSIKAQLQTFVKEDLRKFKDAKKQFDKVSEEKENALVKNAQVQRNKQHEVEEATNILTATRKCFRHIALDYVLQ 159

                         170       180       190       200
                  ....*....|....*....|....*....|....*....|.
gi 2217342963 161 INVLQSKRRSEILKSMLSFMYAHLAFFHQGYDLFSELGPYM 201
Cdd:cd07638   160 INVLQSKRRSEILKSMLSFMYAHLTFFHQGYDLFSELGPYM 200

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 2217342963 383 ESALQRVQCIPGNASCCDCGLADPRWASINLGITLCIECSGIHRSLGVHFSKVRSLTLDTWEPELLKLMCELGNDVINRV 462
Cdd:cd08851     1 ESALQRVQCIPGNASCCDCGLADPRWASINLGITLCIECSGIHRSLGVHFSKVRSLTLDTWEPELLKLMCELGNDVINRI 80

                          90       100       110
                  ....*....|....*....|....*....|....*.
gi 2217342963 463 YEANVEKMGIKKPQPG-QRQEKEAYIRAKYVERKFV 497
Cdd:cd08851    81 YEARVEKMGAKKPQPGgQRQEKEAYIRAKYVERKFV 116

ArfGAP domain of ACAP (ArfGAP with Coiled-coil, ANK repeat and PH domains) proteins; ArfGAP domain is an essential part of ACAP proteins that play important role in endocytosis, actin remodeling and receptor tyrosine kinase-dependent cell movement. ACAP subfamily of ArfGAPs are composed of coiled coils (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. In addition, 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 2217342963 383 ESALQRVQCIPGNASCCDCGLADPRWASINLGITLCIECSGIHRSLGVHFSKVRSLTLDTWEPELLKLMCELGNDVINRV 462
Cdd:cd08835     1 GSALEQVLSVPGNAQCCDCGSPDPRWASINLGVTLCIECSGIHRSLGVHVSKVRSLTLDSWEPELLKVMLELGNDVVNRI 80

                          90       100       110
                  ....*....|....*....|....*....|....*.
gi 2217342963 463 YEANVEKMGIKKPQPG-QRQEKEAYIRAKYVERKFV 497
Cdd:cd08835    81 YEANVPDDGSVKPTPDsSRQEREAWIRAKYVEKKFV 116

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 2217342963 383 ESALQRVQCIPGNASCCDCGLADPRWASINLGITLCIECSGIHRSLGVHFSKVRSLTLDTWEPELLKLMCELGNDVINRV 462
Cdd:cd08850     1 ESILQRVQSIAGNDQCCDCGQPDPRWASINLGILLCIECSGIHRSLGVHCSKVRSLTLDSWEPELLKLMCELGNSTVNQI 80

                          90       100       110
                  ....*....|....*....|....*....|....*.
gi 2217342963 463 YEANVEKMGIKKPQPG-QRQEKEAYIRAKYVERKFV 497
Cdd:cd08850    81 YEAQCEELGLKKPTASsSRQDKEAWIKAKYVEKKFL 116

ArfGAP with coiled-coil, ankyrin repeat and PH domains Pleckstrin homology (PH) domain; ACAP (also called centaurin beta) functions both as a Rab35 effector and as an Arf6-GTPase-activating protein (GAP) by which it controls actin remodeling and membrane trafficking. ACAP contain an NH2-terminal bin/amphiphysin/Rvs (BAR) domain, a phospholipid-binding domain, a PH domain, a GAP domain, and four ankyrin repeats. The AZAPs constitute a family of Arf GAPs that are characterized by an NH2-terminal pleckstrin homology (PH) domain and a central Arf GAP domain followed by two or more ankyrin repeats. On the basis of sequence and domain organization, the AZAP family is further subdivided into four subfamilies: 1) the ACAPs contain an NH2-terminal bin/amphiphysin/Rvs (BAR) domain (a phospholipid-binding domain that is thought to sense membrane curvature), a single PH domain followed by the GAP domain, and four ankyrin repeats; 2) the ASAPs also contain an NH2-terminal BAR domain, the tandem PH domain/GAP domain, three ankyrin repeats, two proline-rich regions, and a COOH-terminal Src homology 3 domain; 3) the AGAPs contain an NH2-terminal GTPase-like domain (GLD), a split PH domain, and the GAP domain followed by four ankyrin repeats; and 4) the ARAPs contain both an Arf GAP domain and a Rho GAP domain, as well as an NH2-terminal sterile-a motif (SAM), a proline-rich region, a GTPase-binding domain, and five PH domains. PMID 18003747 and 19055940 Centaurin can bind to phosphatidlyinositol (3,4,5)P3. 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 2217342963 253 MEGYLFKRASNAFKTWNRRWFSIQNNQLVYQKKF-KDNPTVVVEDLRLCTVKHCEDIERRFCFEVVSPTKSCMLQADSEK 331
Cdd:cd13250     1 KEGYLFKRSSNAFKTWKRRWFSLQNGQLYYQKRDkKDEPTVMVEDLRLCTVKPTEDSDRRFCFEVISPTKSYMLQAESEE 80

                          90
                  ....*....|....*...
gi 2217342963 332 LRQAWIKAVQTSIATAYR 349
Cdd:cd13250    81 DRQAWIQAIQSAIASALN 98

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 2217342963  386 LQRVQCIPGNASCCDCGLADPRWASINLGITLCIECSGIHRSLGVHFSKVRSLTLDTWEPELLKLMCELGNDVINRVYEA 465
Cdd:smart00105   1 LKLLRSIPGNKKCFDCGAPNPTWASVNLGVFLCIECSGIHRSLGVHISKVRSLTLDTWTEEELRLLQKGGNENANSIWES 80

                           90       100       110
                   ....*....|....*....|....*....|....*.
gi 2217342963  466 NVEKMGIKKPQPGQRQEKEAYIRAKYVERKFVDKYS 501
Cdd:smart00105  81 NLDDFSLKPPDDDDQQKYESFIAAKYEEKLFVPPES 116

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 2217342963 385 ALQRVQCIPGNASCCDCGLADPRWASINLGITLCIECSGIHRSLGVHFSKVRSLTLDTWEPELLKLMCELGNDVINRVYE 464
Cdd:cd08836     2 ALQAIRNVRGNDHCVDCGAPNPDWASLNLGALMCIECSGIHRNLGTHISRVRSLDLDDWPVELLKVMSAIGNDLANSVWE 81

                          90       100
                  ....*....|....*....|....*....
gi 2217342963 465 ANVEkmGIKKPQP-GQRQEKEAYIRAKYV 492
Cdd:cd08836    82 GNTQ--GRTKPTPdSSREEKERWIRAKYE 108

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 2217342963 384 SALQRVQCIPGNASCCDCGLADPRWASINLGITLCIECSGIHRSLGVHFSKVRSLTLDTWEPELLKLMCELGNDVINRVY 463
Cdd:cd08834     4 SIIAEVKRLPGNDVCCDCGSPDPTWLSTNLGILTCIECSGVHRELGVHVSRIQSLTLDNLGTSELLLARNLGNEGFNEIM 83

                          90       100       110
                  ....*....|....*....|....*....|....*
gi 2217342963 464 EANVEkmGIKKPQPG-QRQEKEAYIRAKYVERKFV 497
Cdd:cd08834    84 EANLP--PGYKPTPNsDMEERKDFIRAKYVEKKFV 116

Stromal membrane-associated proteins; a subfamily of the ArfGAP family; The SMAP subfamily of Arf GTPase-activating proteins consists of the two structurally-related members, SMAP1 and SMAP2. Each SMAP member exhibits common and distinct functions in vesicle trafficking. They both bind to clathrin heavy chain molecules and are involved in the trafficking of clathrin-coated vesicles. SMAP1 preferentially exhibits GAP toward Arf6, while SMAP2 prefers Arf1 as a substrate. SMAP1 is involved in Arf6-dependent vesicle trafficking, but not Arf6-mediated actin cytoskeleton reorganization, and regulates clathrin-dependent endocytosis of the transferrin receptors and E-cadherin. SMAP2 regulates Arf1-dependent retrograde transport of TGN38/46 from the early endosome to the trans-Golgi network (TGN). SMAP2 has the Clathrin Assembly Lymphoid Myeloid (CALM)-binding domain, but SMAP1 does not.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217342963 393 PGNASCCDCGLADPRWASINLGITLCIECSGIHRSLGVHFSKVRSLTLDTWEPELLKLMCELGNDVINRVYEANVEKmGI 472
Cdd:cd08839     8 EDNKYCADCGAKGPRWASWNLGVFICIRCAGIHRNLGVHISKVKSVNLDSWTPEQVQSMQEMGNARANAYYEANLPD-GF 86

                          90
                  ....*....|....*....
gi 2217342963 473 KKPQPgqRQEKEAYIRAKY 491
Cdd:cd08839    87 RRPQT--DSALENFIRDKY 103

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 2217342963 389 VQCIPGNASCCDCGLADPRWASINLGITLCIECSGIHRSLGVHFSKVRSLTLDTWEPELLKLMCELGNDVINRVYEANVE 468
Cdd:cd17900     9 VKSRPGNSQCCDCGAPDPTWLSTNLGILTCIECSGIHRELGVRYSRIQSLTLDLLSTSELLLAVSMGNTRFNEVMEATLP 88

                          90       100       110
                  ....*....|....*....|....*....|....*
gi 2217342963 469 KMGIKKPQP----GQRQEkeaYIRAKYVERKFVDK 499
Cdd:cd17900    89 AHGGPKPSAesdmGTRKD---YIMAKYVEHRFVRK 120

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 2217342963 385 ALQRVQCIPGNASCCDCGLADPRWASINLGITLCIECSGIHRSLGVHFSKVRSLTLDTWEPELLKLMCELGNDVINRVYE 464
Cdd:cd08854     3 AIQAIRNAKGNSLCVDCGAPNPTWASLNLGALICIECSGIHRNLGTHLSRVRSLDLDDWPRELTLVLTAIGNHMANSIWE 82

                          90       100
                  ....*....|....*....|....*...
gi 2217342963 465 ANVEkmGIKKPQP-GQRQEKEAYIRAKY 491
Cdd:cd08854    83 SCTQ--GRTKPAPdSSREERESWIRAKY 108

ArfGAP domain of ASAP2 (ArfGAP2 with SH3 domain, ANK repeat and PH domain-containing protein 2); The Arf GAPs 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.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217342963 386 LQRVQCIPGNASCCDCGLADPRWASINLGITLCIECSGIHRSLGVHFSKVRSLTLDTWEPELLKLMCELGNDVINRVYEA 465
Cdd:cd08849     6 ISEVQRMTGNDVCCDCGAPDPTWLSTNLGILTCIECSGIHRELGVHYSRMQSLTLDVLGTSELLLAKNIGNAGFNEIMEA 85

                          90       100       110
                  ....*....|....*....|....*....|....*
gi 2217342963 466 NVEKMGIKKPQPGQ-RQEKEAYIRAKYVERKFVDK 499
Cdd:cd08849    86 CLPAEDVVKPNPGSdMNARKDYITAKYIERRYARK 120

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 2217342963 383 ESALQRVQCIPGNASCCDCGLADPRWASINLGITLCIECSGIHRSLGVHFSKVRSLTLDTWEPELLKLMCELGNDVINRV 462
Cdd:cd08848     3 KAIIDDVQRLPGNEVCCDCGSPDPTWLSTNLGILTCIECSGIHREMGVHISRIQSLELDKLGTSELLLAKNVGNNSFNDI 82

                          90       100       110
                  ....*....|....*....|....*....|....*..
gi 2217342963 463 YEANVEKMGIKKPQPGQRQEKEAYIRAKYVERKFVDK 499
Cdd:cd08848    83 MEGNLPSPSPKPSPSSDMTARKEYITAKYVEHRFSRK 119

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
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 2217342963 386 LQRVQCIPGNASCCDCGLADPRWASINLGITLCIECSGIHRSLGVHFSKVRSLTLDTWEPELLKLMCELGND 457
Cdd:cd08830     5 LRELQKLPGNNRCFDCGAPNPQWASVSYGIFICLECSGVHRGLGVHISFVRSITMDSWSEKQLKKMELGGNA 76

Stromal membrane-associated protein 2; a subfamily of the ArfGAP family; The SMAP subfamily of Arf GTPase-activating proteins consists of the two structurally-related members, SMAP1 and SMAP2. Each SMAP member exhibits common and distinct functions in vesicle trafficking. They both bind to clathrin heavy chain molecules and are involved in the trafficking of clathrin-coated vesicles. SMAP1 preferentially exhibits GAP toward Arf6, while SMAP2 prefers Arf1 as a substrate. SMAP1 is involved in Arf6-dependent vesicle trafficking, but not Arf6-mediated actin cytoskeleton reorganization, and regulates clathrin-dependent endocytosis of the transferrin receptors and E-cadherin. SMAP2 regulates Arf1-dependent retrograde transport of TGN38/46 from the early endosome to the trans-Golgi network (TGN). SMAP2 has the Clathrin Assembly Lymphoid Myeloid (CALM)-binding domain, but SMAP1 does not.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217342963 395 NASCCDCGLADPRWASINLGITLCIECSGIHRSLGVHFSKVRSLTLDTWEPELLKLMCELGNDVINRVYEANVEKmGIKK 474
Cdd:cd08859    10 NKFCADCQSKGPRWASWNIGVFICIRCAGIHRNLGVHISRVKSVNLDQWTQEQIQCMQEMGNGKANRLYEAFLPE-NFRR 88

                          90       100
                  ....*....|....*....|.
gi 2217342963 475 PQpgQRQEKEAYIRAKYVERK 495
Cdd:cd08859    89 PQ--TDQAVEGFIRDKYEKKK 107

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
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 2217342963 386 LQRVQCIPGNASCCDCGLADPRWASINLGITLCIECSGIHRSLGVHFSKVRSLTLDTWEPELLKLMCELGND 457
Cdd:cd08831     6 FKKLRSKPENKVCFDCGAKNPTWASVTFGVFLCLDCSGVHRSLGVHISFVRSTNLDSWTPEQLRRMKVGGNA 77

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 2217342963 386 LQRvqciPGNASCCDCGLADPRWASINLGITLCIECSGIHRSLGvHFSKVRSLTLDTWEPELLKLMCELGNDVINRVYEA 465
Cdd:cd08843    12 LQR----PGNARCADCGAPDPDWASYTLGVFICLSCSGIHRNIP-QVSKVKSVRLDAWEEAQVEFMASHGNDAARARFES 86

                          90       100
                  ....*....|....*....|....*..
gi 2217342963 466 NVEKMgIKKPQPGQRQ-EKEAYIRAKY 491
Cdd:cd08843    87 KVPSF-YYRPTPSDCQlLREQWIRAKY 112

ADAP2 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 2217342963 393 PGNASCCDCGLADPRWASINLGITLCIECSGIHRSLGvHFSKVRSLTLDTWEPELLKLMCELGNDVINRVYEANVEKMGI 472
Cdd:cd08844    15 PGNSVCADCGAPDPDWASYTLGIFICLNCSGVHRNLP-DISRVKSIRLDFWEDELVEFMKENGNLKAKAKFEAFVPPFYY 93

                          90
                  ....*....|....*....
gi 2217342963 473 KKPQPGQRQEKEAYIRAKY 491
Cdd:cd08844    94 RPQANDCDVLKEQWIRAKY 112