ARHGEF6

αPIX is a multidomain protein that functions both as a signaling scaffold protein and as an enzyme. αPIX shares this domain structure and signaling function with the highly similar ARHGEF7/βPIX protein. αPIX contains a central DH/PH RhoGEF domain that functions as a guanine nucleotide exchange factor (GEF) for small GTPases of the Rho family, and specifically Rac and Cdc42. as can mutations affecting its binding partner PAK3 whose gene is also located on the X chromosome. In animal models, loss of ARHGEF6 gene function is associated with neuronal synapse defects, immune T-cell migration and maturation defects, and hearing loss. == Interactions ==

αPIX has been reported to interact with over 40 proteins. Major interacting proteins include: • Itself, or the highly-related ARHGEF7/βPIX via a trimeric coiled-coil interaction. • GIT1 or GIT2 dimers via GIT-binding domain. • p21-activated kinases (PAKs) 1, 2 and 3 via SH3 domain. • c-Cbl via SH3 domain. • Rho family GTP-binding protein family members Rac1 and Cdc42, activated via DHPH RhoGEF domain. == See also ==