Rho GDP-dissociation inhibitor 1 (RhoGDI alpha) belongs to the Rho GDI family of proteins. It is found in the cytoplasm where it regulates the GDP/GTP exchange reaction of the Rho, Rac and Cdc42 proteins by inhibiting their dissociation from GDP, and their subsequent binding to GTP. Rho, Rac and Cdc42 are molecular switches involved in the regulation of cytoskeletal structures that affect the regulation of cell morphology, movement, attachment, phagocytosis and cytokinesis.