Members of the G protein-coupled receptor kinase family that phosphorylate the beta2-adrenergic receptor facilitate sequestration.

Published

Journal Article

We recently reported that a beta2-adrenergic receptor (beta2AR) mutant, Y326A, defective in its ability to sequester in response to agonist stimulation was a poor substrate for G protein-coupled receptor kinase (GRK)-mediated phosphorylation; however, its ability to be phosphorylated and sequestered could be restored by overexpressing GRK2 [Ferguson et al. (1995) J. Biol. Chem. 270, 24782]. In the present report, we tested the ability of each of the known GRKs (GRK1-6) to phosphorylate and rescue the sequestration of the Y326A mutant in HEK-293 cells. We demonstrate that in addition to GRK2, GRK3-6 can phosphorylate the Y326A mutant and rescue its sequestration; however, GRK1 was totally ineffective in rescuing either the phosphorylation or the sequestration of the mutant receptor. We found that the agonist-dependent rescue of Y326A mutant phosphorylation by GRK2, -3, and -5 was associated with the agonist-dependent rescue of sequestration. In contrast, overexpression of GRK4 and -6 led mainly to agonist-independent phosphorylation of the Y326A mutant accompanied by increased basal receptor sequestration. Our results demonstrate that phosphorylation per se, but not the interaction with a specific GRK, is required to facilitate beta2AR sequestration.

Full Text

Duke Authors

Cited Authors

  • Ménard, L; Ferguson, SS; Barak, LS; Bertrand, L; Premont, RT; Colapietro, AM; Lefkowitz, RJ; Caron, MG

Published Date

  • April 2, 1996

Published In

Volume / Issue

  • 35 / 13

Start / End Page

  • 4155 - 4160

PubMed ID

  • 8672451

Pubmed Central ID

  • 8672451

International Standard Serial Number (ISSN)

  • 0006-2960

Digital Object Identifier (DOI)

  • 10.1021/bi952961+

Language

  • eng

Conference Location

  • United States