A differential role for endocytosis in receptor-mediated activation of Nox1.

Published

Journal Article

Internalization of activated receptors to a compartment enriched with NAPDH oxidase and associated signaling molecules is expected to facilitate regulation of redox-mediated signal transduction. The aim of this study was to test the hypothesis that endocytosis is necessary for generation of reactive oxygen species (ROS) by Nox1 and for redox-dependent signaling in smooth muscle cells (SMCs). Within minutes of treatment with tumor necrosis factor (TNF)-alpha or thrombin, SMCs increased cellular levels of ROS that was inhibited by shRNA to Nox1. Treatment of SMC with TNF-alpha induced a dynamin-dependent endosomal generation of ROS, whereas thrombin-mediated ROS production did not occur within endosomes and was not prevented by dominant-negative dynamin (dn-dynamin), but instead required transactivation of the epidermal growth factor receptor (EGFR). Activation of the phosphatidylinositol 3-kinase (PI3K)-Akt-activating transcription factor-1 (ATF-1) pathway by TNF-alpha and thrombin were both Nox1- and dynamin-dependent. In conclusion, we show that formation of specific ligand-receptor complexes results in spatially distinct mechanisms of Nox1 activation and generation of ROS. These findings provide novel insights into the role of compartmentalization for integrating redox-dependent cell signaling.

Full Text

Duke Authors

Cited Authors

  • Miller, FJ; Chu, X; Stanic, B; Tian, X; Sharma, RV; Davisson, RL; Lamb, FS

Published Date

  • March 2010

Published In

Volume / Issue

  • 12 / 5

Start / End Page

  • 583 - 593

PubMed ID

  • 19737091

Pubmed Central ID

  • 19737091

Electronic International Standard Serial Number (EISSN)

  • 1557-7716

International Standard Serial Number (ISSN)

  • 1523-0864

Digital Object Identifier (DOI)

  • 10.1089/ars.2009.2857

Language

  • eng