GTPase-activating protein (GAP) for ADP ribosylation factor (ARF). Binds phosphatidylinositol 3-monophosohate (PI-3-P) and anionic phospholipids. Expressed in roots, leaves, flowers and siliques. Low levels of expression in seeds and stems. The C2 domain binds anionic phospholipids promiscuously in the presence of calcium while the N-terminal region (1-174) show a specific affinity for phosphatidylinositol 3-monophosohate.