Differential kinetic and spatial patterns of beta-arrestin and G protein-mediated ERK activation by the angiotensin II receptor.

Published

Journal Article

The seven-membrane-spanning angiotensin II type 1A receptor activates the mitogen-activated protein kinases extracellular signal-regulated kinases 1 and 2 (ERK1/2) by distinct pathways dependent on either G protein (likely G(q)/G(11)) or beta-arrestin2. Here we sought to distinguish the kinetic and spatial patterns that characterize ERK1/2 activated by these two mechanisms. We utilized beta-arrestin RNA interference, the protein kinase C inhibitor Ro-31-8425, a mutant angiotensin II receptor (DRY/AAY), and a mutant angiotensin II peptide (SII-angiotensin), which are incapable of activating G proteins, to isolate the two pathways in HEK-293 cells. G protein-dependent activation was rapid (peak <2 min), quite transient (t((1/2)) approximately 2 min), and led to nuclear translocation of the activated ERK1/2 as assessed by confocal microscopy. In contrast, beta-arrestin2-dependent activation was slower (peak 5-10 min), quite persistent with little decrement noted out to 90 min, and entirely confined to the cytoplasm. Moreover, ERK1/2 activated via beta-arrestin2 accumulated in a pool of cytoplasmic endosomal vesicles that also contained the internalized receptors and beta-arrestin. Such differential regulation of the temporal and spatial patterns of ERK1/2 activation via these two pathways strongly implies the existence of distinct physiological endpoints.

Full Text

Duke Authors

Cited Authors

  • Ahn, S; Shenoy, SK; Wei, H; Lefkowitz, RJ

Published Date

  • August 20, 2004

Published In

Volume / Issue

  • 279 / 34

Start / End Page

  • 35518 - 35525

PubMed ID

  • 15205453

Pubmed Central ID

  • 15205453

International Standard Serial Number (ISSN)

  • 0021-9258

Digital Object Identifier (DOI)

  • 10.1074/jbc.M405878200

Language

  • eng

Conference Location

  • United States