The Yeast Snt2 Protein Coordinates the Transcriptional response to hydrogen peroxide-mediated oxidative stress

Regulation of gene expression is a vital part of the cellular stress response, yet the full set of proteins that orchestrate this regulation remains unknown. Snt2 is a Saccharomyces cerevisiae protein whose function has not been well characterized that was recently shown to associate with Ecm5 and the Rpd3 deacetylase. Here, we confirm that Snt2, Ecm5, and Rpd3 physically associate. We then demonstrate that cells lacking Rpd3 or Snt2 are resistant to hydrogen peroxide (H₂O₂)-mediated oxidative stress and use chromatin immunoprecipitation followed by high-throughput sequencing (ChIP-seq) to show that Snt2 and Ecm5 recruit Rpd3 to a small number of promoters and in response to H₂O₂, colocalize independently of Rpd3 to the promoters of stress response genes. By integrating ChIP-seq and expression analyses, we identify target genes that require Snt2 for proper expression after H₂O₂. Finally, we show that cells lacking Snt2 are also resistant to nutrient stress imparted by the TOR (target of rapamycin) pathway inhibitor rapamycin and identify a common set of genes targeted by Snt2 and Ecm5 in response to both H₂O₂ and rapamycin. Our results establish a function for Snt2 in regulating transcription in response to oxidative stress and suggest Snt2 may also function in multiple stress pathways.