Modulates the activity of the adenylate cyclase catalytic subunit and therefore affects the biosynthesis of cyclic-AMP (By similarity). Plays a role in both surface attachment and surface recognition of appressoria, a highly specialized infection structure for plant penetration. Regulates appressorium formation by coordinated regulation of cAMP signaling and Pmk1 MAPK pathways (PubMed:24835254). Alternates between an inactive form bound to GDP and an active form bound to GTP. Activated by a guanine nucleotide-exchange factor (GEF) and inactivated by a GTPase-activating protein (GAP). Interacts with farnesyltransferase beta subunit RAM1. Belongs to the small GTPase superfamily. Ras family.