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RhoGAP_p190: RhoGAP (GTPase-activator protein [GAP] for Rho-like small GTPases) domain of p190-like proteins. p190, also named RhoGAP5, plays a role in neuritogenesis and axon branch stability. p190 shows a preference for Rho, over Rac and Cdc42, and consists of an N-terminal GTPase domain and a C-terminal GAP domain. The central portion of p190 contains important regulatory phosphorylation sites. 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.