G protein-coupled receptor kinase 4 (GRK4) is an enzyme that is encoded by the GRK4 gene in humans.[5]
AliasesGRK4, GPRK2L, GPRK4, GRK4a, IT11, G protein-coupled receptor kinase 4 Quick facts Available structures, PDB ...
Close
This gene encodes a member of the G protein-coupled receptor kinase subfamily of the Ser/Thr protein kinase family, and is most similar to GRK5 and GRK6.[6]
G protein-coupled receptor kinases phosphorylate activated G protein-coupled receptors, which promotes the binding of an arrestin protein to the receptor. Arrestin binding to a phosphorylated, active receptor prevents receptor stimulation of heterotrimeric G protein transducer proteins, blocking their cellular signaling and resulting in receptor desensitization. Moreover Arrestin binding to a phosphorylated, active receptor also enables receptor signaling through arrestin partner proteins. Consequently the GRK/arrestin system serves as a signaling switch for G protein-coupled receptors.[7]
GRK4 is most highly expressed in the testes, with lower amounts found in the brain, kidney and other tissues. It exists in four alternatively-spliced variants.[8]
Polymorphisms in the GRK4 gene have been linked to both genetic and acquired hypertension, partly acting through kidney dopamine receptors.[9][10]
