RAC1 — Aspergillus fumigatus

Summary

AFU2G05740 (RAC1, also known as CDC42) in Aspergillus fumigatus encodes a small Rho GTPase (ModA, putative) with GTPase activity, GDP and GTP binding, protein serine/threonine kinase activator activity, and signaling adaptor activity. It is associated with the regulation of cell morphogenesis, bipolar cell growth, budding-to-filamentous growth switching, septin ring organization, cell wall modification, chemotaxis, integrin activation, and positive regulation of 1,3-beta-D-glucan biosynthetic process. The gene is linked to exocytic vesicles, the hyphal tip polarisome, the Spitzenkörper, and the 1,3-beta-glucan synthase complex. Phenotypic associations include abnormal filamentous and pseudohyphal growth, decreased osmotic stress resistance, delayed sporulation, decreased cell death, and altered cell cycle progression. Studies of related genes in other species link the family to loss of pathogenicity and reduced virulence.