Regulation of the methylation status of G protein-coupled receptor kinase 1 (rhodopsin kinase)

► We examined the regulation of rhodopsin kinase (GRK1) α-carboxymethylation in vitro. ► Considerable fraction GRK1 is endogenously methylated in isolated rod outer segments. ► GRK1demethylation is inhibited in the presence of Ca2 + by recoverin. ► This effect requires recoverin myristoylation and the presence of the membranes. ► Ca2 +-dependence of GRK1 methylation state may contribute to light adaptation.