RhoGAP_fMSB1: RhoGAP (GTPase-activator protein [GAP] for Rho-like small GTPases) domain of fungal MSB1-like proteins. Msb1 was originally identified as a multicopy suppressor of temperature sensitive cdc42 mutation. Msb1 is a positive regulator of the Pkc1p-MAPK pathway and 1,3-beta-glucan synthesis, both pathways involve Rho1 regulation. 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.
Jiyao W et al.(2023). "The conserved domain database in 2023.",