Enables GTPase activating protein binding activity and guanyl-nucleotide exchange factor activity. Involved in regulation of protein transport. Located in cytosol. Is expressed in several structures, including gonad; inner ear; nervous system; nucleus pulposus; and thymus primordium. Orthologous to human GAPVD1 (GTPase activating protein and VPS9 domains 1). [provided by Alliance of Genome Resources, Apr 2022]