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 76879693   1 YGVFLCIDCSGVHRSLGVHLSFIRSTELDSNWNWFQLRCMQVGGNANATAFFRQHGCTANDANTKYNSRAAQMYREKIRQ 80
Cdd:cd09029  37 YGVFLCIDCSGVHRSLGVHLSFIRSTELDSNWNWFQLRCMQVGGNANATAFFRQHGCTTNDANAKYNSRAAQMYREKIRQ 116

                ....
gi 76879693  81 LGSA 84
Cdd:cd09029 117 LASA 120

Uncharacterized membrane protein YqiK, contains Band7/PHB/SPFH domain [Function unknown];

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|....
gi 76879693 202 SEIERQAQVAEKLREQQAADAKKQAEESmVASMRLAYQELQIDRKKEEKKLQnlEGKKREQAER 265
Cdd:COG2268 206 AEAERETEIAIAQANREAEEAELEQERE-IETARIAEAEAELAKKKAEERRE--AETARAEAEA 266

Arf1 GTPase-activating protein 2; 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 76879693   1 YGVFLCIDCSGVHRSLGVHLSFIRSTELDSNWNWFQLRCMQVGGNANATAFFRQHGCTANDANTKYNSRAAQMYREKIRQ 80
Cdd:cd09029  37 YGVFLCIDCSGVHRSLGVHLSFIRSTELDSNWNWFQLRCMQVGGNANATAFFRQHGCTTNDANAKYNSRAAQMYREKIRQ 116

                ....
gi 76879693  81 LGSA 84
Cdd:cd09029 117 LASA 120

Putative GTPase activating protein for 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 76879693     1 YGVFLCIDCSGVHRSLGVHLSFIRSTELDSnWNWFQLRCMQVGGNANATAFFRQHG-----CTANDANTKYNSRAAQMYR 75
Cdd:pfam01412  31 LGIFICIDCSGVHRSLGVHISKVRSLTLDT-WTDEQLELMKAGGNDRANEFWEANLppsykPPPSSDREKRESFIRAKYV 109

                  ..
gi 76879693    76 EK 77
Cdd:pfam01412 110 EK 111

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 76879693   1 YGVFLCIDCSGVHRSLGVHLSFIRSTELDsNWNWFQLRCMQVGGNANATAFFRQHG--CTANDANTKYNSRAAQMYREKI 78
Cdd:COG5347  38 LGVFLCIDCAGVHRSLGVHISKVKSLTLD-NWTEEELRRMEVGGNSNANRFYEKNLldQLLLPIKAKYDSSVAKKYIRKK 116

                        90       100       110       120       130       140       150       160
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 76879693  79 RQLGsaalarhgtdLWIDNMSSAvpnhSPEKKDSDFFTEHTQPPawdaPATEPSGTQQPAPSTESSGLAQPEHGPNTDLL 158
Cdd:COG5347 117 YELK----------KFIDDSSSP----SDFSSFSASSTRTVDSV----DDRLDSESQSRSSSASLGNSNRPDDELNVESF 178

                       170
                ....*....|...
gi 76879693 159 GTSPKASLELKSS 171
Cdd:COG5347 179 QSTGSKPRSLTST 191

Arf1 GTPase-activating protein 2; 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 76879693   1 YGVFLCIDCSGVHRSLGVHLSFIRSTELDSNWNWFQLRCMQVGGNANATAFFRQHGCTANDANTKYNSRAAQMYREKIRQ 80
Cdd:cd09029  37 YGVFLCIDCSGVHRSLGVHLSFIRSTELDSNWNWFQLRCMQVGGNANATAFFRQHGCTTNDANAKYNSRAAQMYREKIRQ 116

                ....
gi 76879693  81 LGSA 84
Cdd:cd09029 117 LASA 120

ARF1 GTPase-activating protein 1-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 76879693   1 YGVFLCIDCSGVHRSLGVHLSFIRSTELDSnWNWFQLRCMQVGGNANATAFFRQHGCTAN-DANTKYNSRAAQMYREKIR 79
Cdd:cd08959  32 YGIFICLDCSGVHRGLGVHISFVRSTTMDK-WTEEQLRKMKVGGNANAREFFKQHGIYDSmDIKEKYNSRAAALYRDKLA 110

                ....*
gi 76879693  80 QLGSA 84
Cdd:cd08959 111 ALAEG 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 76879693   1 YGVFLCIDCSGVHRSLGVHLSFIRSTELDSnWNWFQLRCMQVGGNANATAFFRQHGCTAN-DANTKYNSRAAQMYREKIR 79
Cdd:cd08830  32 YGIFICLECSGVHRGLGVHISFVRSITMDS-WSEKQLKKMELGGNAKLREFFESYGISPDlPIREKYNSKAAELYREKLA 110

Putative GTPase activating protein for 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 76879693     1 YGVFLCIDCSGVHRSLGVHLSFIRSTELDSnWNWFQLRCMQVGGNANATAFFRQHG-----CTANDANTKYNSRAAQMYR 75
Cdd:pfam01412  31 LGIFICIDCSGVHRSLGVHISKVRSLTLDT-WTDEQLELMKAGGNDRANEFWEANLppsykPPPSSDREKRESFIRAKYV 109

                  ..
gi 76879693    76 EK 77
Cdd:pfam01412 110 EK 111

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 76879693   1 YGVFLCIDCSGVHRSLGVHLSFIRSTELDsNWNWFQLRCMQVGGNANATAFFRQHG--CTANDANTKYNSRAAQMYREKI 78
Cdd:COG5347  38 LGVFLCIDCAGVHRSLGVHISKVKSLTLD-NWTEEELRRMEVGGNSNANRFYEKNLldQLLLPIKAKYDSSVAKKYIRKK 116

                        90       100       110       120       130       140       150       160
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 76879693  79 RQLGsaalarhgtdLWIDNMSSAvpnhSPEKKDSDFFTEHTQPPawdaPATEPSGTQQPAPSTESSGLAQPEHGPNTDLL 158
Cdd:COG5347 117 YELK----------KFIDDSSSP----SDFSSFSASSTRTVDSV----DDRLDSESQSRSSSASLGNSNRPDDELNVESF 178

                       170
                ....*....|...
gi 76879693 159 GTSPKASLELKSS 171
Cdd:COG5347 179 QSTGSKPRSLTST 191

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
                ....*....|....*....|....*....|....*....|....*....|....
gi 76879693   2 GVFLCIDCSGVHRSLGVHLSFIRSTELDSnWNWFQLRCMQVGGNANATAFFRQH 55
Cdd:cd08839  29 GVFICIRCAGIHRNLGVHISKVKSVNLDS-WTPEQVQSMQEMGNARANAYYEAN 81

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
                ....*....|....*....|....*....|....*....|....*....|.
gi 76879693   2 GVFLCIDCSGVHRSLGVHLSFIRSTELDsNWNWFQLRCMQVGGNANATAFF 52
Cdd:cd08859  29 GVFICIRCAGIHRNLGVHISRVKSVNLD-QWTQEQIQCMQEMGNGKANRLY 78

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
                ....*....|....*....|....*....|....*....|....*..
gi 76879693   2 GVFLCIDCSGVHRSLGVHLSFIRSTELDSnWNWFQLRCMQVGGNANA 48
Cdd:cd08836  31 GALMCIECSGIHRNLGTHISRVRSLDLDD-WPVELLKVMSAIGNDLA 76

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
                ....*....|....*....|....*....|....*....|....*
gi 76879693   2 GVFLCIDCSGVHRSLGVHLSFIRSTELDSnWNWFQLRCMQVGGNA 46
Cdd:cd08850  32 GILLCIECSGIHRSLGVHCSKVRSLTLDS-WEPELLKLMCELGNS 75

ArfGAP domain of ACAP1 (ArfGAP with Coiled-coil, ANK repeat and PH domains 1); ACAP1 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 76879693   2 GVFLCIDCSGVHRSLGVHLSFIRSTELDSnWNWFQLRCMQVGGNanataffrqhgctaNDANTKYNSRAAQMyreKIRQL 81
Cdd:cd08852  32 GVTLCIQCSGIHRSLGVHFSKVRSLTLDS-WEPELVKLMCELGN--------------VIINQIYEARIEAM---AIKKP 93

                        90
                ....*....|....
gi 76879693  82 GSAAlARHGTDLWI 95
Cdd:cd08852  94 GPSS-SRQEKEAWI 106

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
                ....*....|....*....|....*....|....*....|....*....|....*....
gi 76879693   2 GVFLCIDCSGVHRSLGVHLSFIRSTELDsNWNWFQLRCMQVGGN--ANATAFFRQHGCT 58
Cdd:cd08854  32 GALICIECSGIHRNLGTHLSRVRSLDLD-DWPRELTLVLTAIGNhmANSIWESCTQGRT 89

The GIT subfamily of ADP-ribosylation factor GTPase-activating proteins; The GIT (G-protein coupled receptor kinase-interacting protein) subfamily includes GIT1 and GIT2, which have three ANK repeats, a Spa-homology domain (SHD), a coiled-coil domain and a C-terminal paxillin-binding site (PBS). The GIT1/2 proteins are GTPase-activating proteins that function as an inactivator of Arf signaling, and interact with the PIX/Cool family of Rac/Cdc42 guanine nucleotide exchange factors (GEFs). Unlike other ArfGAPs, GIT and PIX (Pak-interacting exchange factor) proteins are tightly associated to form an oligomeric complex that acts as a scaffold and signal integrator that can be recruited for multiple signaling pathways. The GIT/PIX complex functions as a signaling scaffold by binding to specific protein partners. As a result, the complex is transported to specific cellular locations. For instance, the GIT partners paxillin or integrin-alpha4 (to focal adhesions), piccolo and liprin-alpha (to synapses), and the beta-PIX partner Scribble (to epithelial cell-cell contacts and synapses). Moreover, the GIT/PIT complex functions to integrate signals from multiple GTP-binding protein and protein kinase pathways to regulate the actin cytoskeleton and thus cell polarity, adhesion and migration.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....
gi 76879693   2 GVFLCIDCSGVHRSLGVHLSFIRSTELDsNWNWFQLRCMQVGGNANATAFFrQH 55
Cdd:cd08833  27 GVLICDECCSIHRSLGRHISQVKSLRKD-QWPPSLLEMVQTLGNNGANSIW-EH 78

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
                ....*....|....*....|....*...
gi 76879693   2 GVFLCIDCSGVHRSLGVHLSFIRSTELD 29
Cdd:cd08848  34 GILTCIECSGIHREMGVHISRIQSLELD 61

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.

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gi 76879693   2 GVFLCIDCSGVHRSLGVHLSFIRSTELD 29
Cdd:cd08849  34 GILTCIECSGIHRELGVHYSRMQSLTLD 61

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.

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gi 76879693   2 GVFLCIDCSGVHRSLGvHLSFIRSTELDSnWNWFQLRCMQVGGNANATAFF 52
Cdd:cd08843  36 GVFICLSCSGIHRNIP-QVSKVKSVRLDA-WEEAQVEFMASHGNDAARARF 84

Uncharacterized membrane protein YqiK, contains Band7/PHB/SPFH domain [Function unknown];

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gi 76879693 202 SEIERQAQVAEKLREQQAADAKKQAEESmVASMRLAYQELQIDRKKEEKKLQnlEGKKREQAER 265
Cdd:COG2268 206 AEAERETEIAIAQANREAEEAELEQERE-IETARIAEAEAELAKKKAEERRE--AETARAEAEA 266

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.

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gi 76879693   2 GVFLCIDCSGVHRSLGVHLSFIRSTELDSN-WNWFQLRCMQVGGNANATAF 51
Cdd:cd08856  37 CVVICKKCAGQHRSLGPKDSKVRSLKMDASiWSNELIELFIVVGNKPANLF 87

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.

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gi 76879693   2 GVFLCIDCSGVHRSLGVHLSFIRSTELD-SNWNWFQLRCMQVGGNANATAFFRQH 55
Cdd:cd17902  32 CVVICKQCAGQHRSLGSGISKVQSLKLDtSVWSNEIVQLFIVLGNDRANRFWAAR 86