biostudies-literatureUnknown183(4)Weimer CThe formation of coat protein complex I (COPI)-coated vesicles is regulated by the small guanosine triphosphatase (GTPase) adenosine diphosphate ribosylation factor 1 (Arf1), which in its GTP-bound form recruits coatomer to the Golgi membrane. Arf GTPase-activating protein (GAP) catalyzed GTP hydrolysis in Arf1 triggers uncoating and is required for uptake of cargo molecules into vesicles. Three mammalian ArfGAPs are involved in COPI vesicle trafficking; however, their individual functions remain obscure. ArfGAP1 binds to membranes depending on their curvature. In this study, we show that ArfGAP2 and ArfGAP3 do not bind directly to membranes but are recruited via interactions with coatomer. In the presence of coatomer, ArfGAP2 and ArfGAP3 activities are comparable with or even higher than The Journal of cell biology725-35https://www.ebi.ac.uk/biostudies/studies/S-EPMC2582887biostudies-literatureDifferential roles of ArfGAP1, ArfGAP2, and ArfGAP3 in COPI trafficking.PMC2582887Beck RMoelleken JBrugger BReckmann IWeimer CWieland FEckert PfalseDifferential roles of ArfGAP1, ArfGAP2, and ArfGAP3 in COPI trafficking.The formation of coat protein complex I (COPI)-coated vesicles is regulated by the small guanosine triphosphatase (GTPase) adenosine diphosphate ribosylation factor 1 (Arf1), which in its GTP-bound form recruits coatomer to the Golgi membrane. Arf GTPase-activating protein (GAP) catalyzed GTP hydrolysis in Arf1 triggers uncoating and is required for uptake of cargo molecules into vesicles. Three mammalian ArfGAPs are involved in COPI vesicle trafficking; however, their individual functions remain obscure. ArfGAP1 binds to membranes depending on their curvature. In this study, we show that ArfGAP2 and ArfGAP3 do not bind directly to membranes but are recruited via interactions with coatomer. In the presence of coatomer, ArfGAP2 and ArfGAP3 activities are comparable with or even higher than 2008-01-01T00:00:00Z2008 Nov2025-04-26T00:30:15.677Z2019-03-27T00:19:20ZS-EPMC25828871901531910.1083/jcb.200806140