May act as a downstream effector of CDC42 in cytoskeletal reorganization. Contributes to the actomyosin contractility required for cell invasion, through the regulation of MYPT1 and thus MLC2 phosphorylation (By similarity). ATP + L-seryl-[protein] = ADP + H(+) + O-phospho-L-seryl-[protein] ATP + L-threonyl-[protein] = ADP + H(+) + O-phospho-L-threonyl-[protein] Maintained in an inactive, closed conformation by an interaction between the kinase domain and the negative autoregulatory C-terminal coiled-coil region. Agonist binding to the phorbol ester binding site disrupts this, releasing the kinase domain to allow N-terminus-mediated dimerization and kinase activation by transautophosphorylation (By similarity). Homodimer and homotetramer via the coiled coil regions. Interacts tightly with GTP-bound but not GDP-bound CDC42 (By similarity). Concentrates at the leading edge of cells. Expressed in heart and skeletal muscle. Belongs to the protein kinase superfamily. AGC Ser/Thr protein kinase family. DMPK subfamily.