PRKG1/PKG1

PRKG1 encodes cGMP-dependent protein kinase 1, the principal effector of nitric oxide-cGMP signaling in smooth muscle and platelets. Alternative promoter usage and splicing generate the PKG1alpha and PKG1beta isoforms, which share a cGMP-binding regulatory region and a serine/threonine kinase domain but differ at their N-termini. cGMP binding activates PKG1 to phosphorylate targets that lower cytosolic calcium, producing vasodilation, inhibition of smooth-muscle proliferation and suppression of platelet aggregation. PRKG1 variants have been associated with aortic disease phenotypes. Recombinant PKG1 is a standard tool for studying vascular relaxation mechanisms and for evaluating compounds acting through the NO-sGC-cGMP axis.