G-protein-coupled receptor kinase 2 (GRK2), also known as beta-adrenergic receptor kinase 1 (beta-ARK1), is a member of the GRK family, which phosphorylates the activated form of G-protein-coupled receptors (GPCRs) and initiates the desensitization process of GPCR. It is an ubiquitous cytosolic enzyme that specifically phosphorylates the activated form of the beta-adrenergic and related G-protein-coupled receptors. PKC phosphorylation enhances GRK2 activity by promoting its membrane localization and by abolishing the inhibitory association of calmodulin.
