Essential role for G protein-coupled receptor endocytosis in the activation of mitogen-activated protein kinase.

Published

Journal Article

The classical paradigm for G protein-coupled receptor (GPCR) signal transduction involves the agonist-dependent interaction of GPCRs with heterotrimeric G proteins at the plasma membrane and the subsequent generation, by membrane-localized effectors, of soluble second messengers or ion currents. Termination of GPCR signals follows G protein-coupled receptor kinase (GRK)- and beta-arrestin-mediated receptor uncoupling and internalization. Here we show that these paradigms are inadequate to account for GPCR-mediated, Ras-dependent activation of the mitogen-activated protein (MAP) kinases Erk1 and -2. In HEK293 cells expressing dominant suppressor mutants of beta-arrestin or dynamin, beta2-adrenergic receptor-mediated activation of MAP kinase is inhibited. The inhibitors of receptor internalization specifically blocked Raf-mediated activation of MEK. Plasma membrane-delimited steps in the GPCR-mediated activation of the MAP kinase pathway, such as tyrosine phosphorylation of Shc and Raf kinase activation by Ras, are unaffected by inhibitors of receptor internalization. Thus, GRKs and beta-arrestins, which uncouple GPCRs and target them for internalization, function as essential elements in the GPCR-mediated MAP kinase signaling cascade.

Full Text

Duke Authors

Cited Authors

  • Daaka, Y; Luttrell, LM; Ahn, S; Della Rocca, GJ; Ferguson, SS; Caron, MG; Lefkowitz, RJ

Published Date

  • January 9, 1998

Published In

Volume / Issue

  • 273 / 2

Start / End Page

  • 685 - 688

PubMed ID

  • 9422717

Pubmed Central ID

  • 9422717

International Standard Serial Number (ISSN)

  • 0021-9258

Digital Object Identifier (DOI)

  • 10.1074/jbc.273.2.685

Language

  • eng

Conference Location

  • United States