Iron regulation through the back door: iron-dependent metabolite levels contribute to transcriptional adaptation to iron deprivation in Saccharomyces cerevisiae.

ABSTRACT: Budding yeast (Saccharomyces cerevisiae) responds to iron deprivation both by Aft1-Aft2-dependent transcriptional activation of genes involved in cellular iron uptake and by Cth1-Cth2-specific degradation of certain mRNAs coding for iron-dependent biosynthetic components. Here, we provide evidence for a novel principle of iron-responsive gene expression. This regulatory mechanism is based on the modulation of transcription through the iron-dependent variation of levels of regulatory metabolites. As an example, the LEU1 gene of branched-chain amino acid biosynthesis is downregulated under iron-limiting conditions through depletion of the metabolic intermediate alpha-isopropylmalate, which functions as a key transcriptional coactivator of the Leu3 transcription factor. Synthesis of alpha-iso

SUBMITTER: Ihrig J 

PROVIDER: S-EPMC2837980 | biostudies-literature | 2010 Mar

REPOSITORIES: biostudies-literature