Oxidative and electrophilic stresses activate Nrf2 through inhibition of ubiquitination activity of Keap1.

ABSTRACT: The Keap1-Nrf2 system is the major regulatory pathway of cytoprotective gene expression against oxidative and/or electrophilic stresses. Keap1 acts as a stress sensor protein in this system. While Keap1 constitutively suppresses Nrf2 activity under unstressed conditions, oxidants or electrophiles provoke the repression of Keap1 activity, inducing the Nrf2 activation. However, the precise molecular mechanisms behind the liberation of Nrf2 from Keap1 repression in the presence of stress remain to be elucidated. We hypothesized that oxidative and electrophilic stresses induce the nuclear accumulation of Nrf2 by affecting the Keap1-mediated rapid turnover of Nrf2, since such accumulation was diminished by the protein synthesis inhibitor cycloheximide. While both the Cys273 and Cys288 residues

SUBMITTER: Kobayashi A 

PROVIDER: S-EPMC1317630 | biostudies-literature | 2006 Jan

REPOSITORIES: biostudies-literature