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RhoGAP_ARAP: RhoGAP (GTPase-activator protein [GAP] for Rho-like small GTPases) domain present in ARAPs. ARAPs (also known as centaurin deltas) contain, besides the RhoGAP domain, an Arf GAP, ankyrin repeat ras-associating, and PH domains. Since their ArfGAP activity is PIP3-dependent, ARAPs are considered integration points for phosphoinositide, Arf and Rho signaling. Small GTPases cluster into distinct families, and all act as molecular switches, active in their GTP-bound form but inactive when GDP-bound. The Rho family of GTPases activates effectors involved in a wide variety of developmental processes, including regulation of cytoskeleton formation, cell proliferation and the JNK signaling pathway. GTPases generally have a low intrinsic GTPase hydrolytic activity but there are family-specific groups of GAPs that enhance the rate of GTP hydrolysis by several orders of magnitude.