GTPase-activating protein (GAP) that stimulates specifically the intrinsic GTPase activity of Ypt/Rab-type GTPases YPT1 and YPT7 (PubMed:11359917, PubMed:19386605). Functions on the Golgi as a negative regulator of YPT1 (PubMed:11359917). Functions on the vacuole as a negative regulator of YPT7 (PubMed:11118206, PubMed:19386605). It is also active on SEC4 and YPT51 (PubMed:10508155). Provides a catalytic arginine (arginine finger) and glutamine (glutamine finger) in trans to accelerate the GTP hydrolysis rate of the substrate GTPase (Probable) (PubMed:16855591). Present with 206 molecules/cell in log phase SD medium.