[Regulation of G protein-coupled receptor kinase activity].
Recent progress on the activation of G protein-coupled receptor kinases is reviewed. beta-Adrenergic receptor kinase (beta ARK) is activated by G protein beta gamma -subunits, which interact with the carboxyl terminal portion of beta ARK. Muscarinic receptor m2-subtypes are phosphorylated by beta ARK1 in the central part of the third intracellular loop (I3). Phosphorylation of I3-GST fusion protein by beta ARK1 is synergistically stimulated by the beta gamma -subunits and mastoparan or a peptide corresponding to portions adjacent to the transmembrane segments of m2-receptors or by beta gamma -subunits and the agonist-bound I3-deleted m2 variant. These results indicate that agonist-bound receptors serve as both substrates and activators of beta ARK.
Institute for Brain Research, Faculty of Medicine, University of Tokyo, Japan.
T
T
Haga
K
K
Haga
K
K
Kameyama
H
H
Nakata
D000818:Animals; D017868:Cyclic AMP-Dependent Protein Kinases / Q000378:metabolism*; D005136:Eye Proteins; D051606:G-Protein-Coupled Receptor Kinase 1; D054769:G-Protein-Coupled Receptor Kinase 2; D019204:GTP-Binding Proteins / Q000378:metabolism*; D010766:Phosphorylation; D011485:Protein Binding; D011494:Protein Kinases / Q000378:metabolism*; D020794:Receptor Protein-Tyrosine Kinases / Q000378:metabolism; D011976:Receptors, Muscarinic / Q000378:metabolism; D051552:beta-Adrenergic Receptor Kinases
D005136:Eye Proteins; D011976:Receptors, Muscarinic; D011494:Protein Kinases; D020794:Receptor Protein-Tyrosine Kinases; D017868:Cyclic AMP-Dependent Protein Kinases; D051606:G-Protein-Coupled Receptor Kinase 1; D051552:beta-Adrenergic Receptor Kinases; C080577:muscarinic receptor kinase; D054769:G-Protein-Coupled Receptor Kinase 2; D019204:GTP-Binding Proteins