Different G protein-coupled receptor kinases govern G protein and beta-arrestin-mediated signaling of V2 vasopressin receptor.
Signaling through beta-arrestins is a recently appreciated mechanism used by seven-transmembrane receptors. Because G protein-coupled receptor kinase (GRK) phosphorylation of such receptors is generally a prerequisite for beta-arrestin binding, we studied the roles of different GRKs in promoting beta-arrestin-mediated extracellular signal-regulated kinase (ERK) activation by a typical seven-transmembrane receptor, the Gs-coupled V2 vasopressin receptor. Gs- and beta-arrestin-mediated pathways to ERK activation could be distinguished with H89, an inhibitor of protein kinase A, and beta-arrestin 2 small interfering RNA, respectively. The roles of GRK2, -3, -5, and -6 were assessed by suppressing their expression with specific small interfering RNA sequences. By using this approach, we demonstrated that GRK2 and -3 are responsible for most of the agonist-dependent receptor phosphorylation, desensitization, and recruitment of beta-arrestins. In contrast, GRK5 and -6 mediated much less receptor phosphorylation and beta-arrestin recruitment, but yet appeared exclusively to support beta-arrestin 2-mediated ERK activation. GRK2 suppression actually increased beta-arrestin-stimulated ERK activation. These results suggest that beta-arrestin recruited in response to receptor phosphorylation by different GRKs has distinct functional potentials.
Ren
Xiu-Rong
XR
Department of Biochemistry, Howard Hughes Medical Institute, Duke University Medical Center, Durham, NC 27710, USA.
Reiter
Eric
E
Ahn
Seungkirl
S
Kim
Jihee
J
Chen
Wei
W
Lefkowitz
Robert J
RJ
D019390:Arrestins / Q000502:physiology*; D001483:Base Sequence; D017868:Cyclic AMP-Dependent Protein Kinases / Q000235:genetics; D048049:Extracellular Signal-Regulated MAP Kinases / Q000037:antagonists & inhibitors; D054774:G-Protein-Coupled Receptor Kinase 5; D054768:G-Protein-Coupled Receptor Kinases; D019204:GTP-Binding Proteins / Q000502:physiology*; D006801:Humans; D007546:Isoquinolines / Q000494:pharmacology; D007700:Kinetics; D010766:Phosphorylation; D017346:Protein Serine-Threonine Kinases / Q000235:genetics; D034741:RNA, Small Interfering / Q000235:genetics; D020794:Receptor Protein-Tyrosine Kinases / Q000502:physiology*; D043562:Receptors, G-Protein-Coupled / Q000235:genetics / Q000378:metabolism*; D017483:Receptors, Vasopressin / Q000502:physiology*; D015398:Signal Transduction; D013449:Sulfonamides / Q000494:pharmacology; D014162:Transfection; D051552:beta-Adrenergic Receptor Kinases; D000071560:beta-Arrestin 2; D000071557:beta-Arrestins
C000605254:ARRB2 protein, human; D019390:Arrestins; D007546:Isoquinolines; D034741:RNA, Small Interfering; D043562:Receptors, G-Protein-Coupled; D017483:Receptors, Vasopressin; D013449:Sulfonamides; D000071560:beta-Arrestin 2; D000071557:beta-Arrestins; C044388:N-(2-aminoethyl)-5-isoquinolinesulfonamide; D020794:Receptor Protein-Tyrosine Kinases; D017346:Protein Serine-Threonine Kinases; D017868:Cyclic AMP-Dependent Protein Kinases; D051552:beta-Adrenergic Receptor Kinases; D054774:G-Protein-Coupled Receptor Kinase 5; D054768:G-Protein-Coupled Receptor Kinases; C089176:G-protein-coupled receptor kinase 6; C517898:GRK5 protein, human; D048049:Extracellular Signal-Regulated MAP Kinases; D019204:GTP-Binding Proteins