ADP-ribosylation factor GTPase-activating protein 1 is an enzyme that in humans is encoded by the ARFGAP1 gene.

The protein encoded by this gene is a GTPase-activating protein (GAP) which associates with the Golgi apparatus and which interacts with ADP-ribosylation factor 1 (ARF1). The encoded protein promotes hydrolysis of ARF1-bound GTP and is required for 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. The activity of this protein is stimulated by phosphoinosides and inhibited by phosphatidylcholine. Two transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Jul 2008].
Function: GTPase-activating protein (GAP) for the ADP ribosylation factor 1 (ARF1). Involved in membrane trafficking and /or vesicle transport. Promotes hydrolysis of the ARF1-bound GTP and thus, is required for the dissociation of coat proteins from Golgi-derived membranes and vesicles, a prerequisite for vesicle's fusion with target compartment. Probably regulates ARF1-mediated transport via its interaction with the KDELR proteins and RNP24. Overexpression induces the redistribution of the entire Golgi complex to the endoplasmic reticulum, as when ARF1 is deactivated. Its activity is stimulated by phosphoinosides and inhibited by phosphatidylcholine (By similarity).