Gcn4 is required for the response to peroxide stress in the yeast Saccharomyces cerevisiae.

ABSTRACT: An oxidative stress occurs when reactive oxygen species overwhelm the cellular antioxidant defenses. We have examined the regulation of protein synthesis in Saccharomyces cerevisiae in response to oxidative stress induced by exposure to hydroperoxides (hydrogen peroxide, and cumene hydroperoxide), a thiol oxidant (diamide), and a heavy metal (cadmium). Examination of translational activity indicates that these oxidants inhibit translation at the initiation and postinitiation phases. Inhibition of translation initiation in response to hydroperoxides is entirely dependent on phosphorylation of the alpha subunit of eukaryotic initiation factor (eIF)2 by the Gcn2 kinase. Activation of Gcn2 is mediated by uncharged tRNA because mutation of its HisRS domain abolishes regulation in response to hy

SUBMITTER: Mascarenhas C 

PROVIDER: S-EPMC2441660 | biostudies-literature | 2008 Jul

REPOSITORIES: biostudies-literature