Protein kinases and phosphatases: regulation by autoinhibitory domains

Numerous enzymes which can be activated by allosteric ligands appear to contain autoinhibitory domains which, through interaction with the catalytic domains, maintain the enzymes in their inactive states. Binding of activator ligands alters the conformation of the autoinhibitory domain and neutralizes its inhibitory potency, thereby producing enzyme activation. Such autoinhibitory domains have been intensively studied in several protein kinase and phosphatases. This review summarizes our current understanding of these autoinhibitory domains in selected protein kinases and phosphatases.