Cooperative Regulation of DOG2 , Encoding 2-Deoxyglucose-6-Phosphate Phosphatase, by Snf1 Kinase and the High-Osmolarity Glycerol–Mitogen-Activated Protein Kinase Cascade in Stress Responses of Saccharomyces cerevisiae

Abstract

We screened the genome of Saccharomyces cerevisiae for the genes responsive to oxidative stress by using the lacZ transposon-insertion library. As a result, we found that expression of the DOG2 gene coding for 2-deoxyglucose-6-phosphate phosphatase was induced by oxidative stress. The expression of DOG2 was also induced by osmotic stress. We found a putative cis element (STRE, a stress response element) in the DOG2 promoter adjacent to a consensus sequence to which the Mig1p repressor is known to bind. The basal levels of DOG2 gene expression were increased in a mig1Delta mutant, while the derepression of DOG2 was not observed in a snf1Delta mutant under glucose-deprived conditions. Induction of the DOG2 gene expression by osmotic stress was observed in any of the three disruptants pbs2Delta, hog1Delta, and snf1Delta. However, the osmotic induction was completely abolished in both the snf1Delta pbs2Delta mutant and the snf1Delta hog1Delta mutant. Additionally, these single mutants as well as double mutants failed to induce DOG2 expression by oxidative stress. These results suggest that Snf1p kinase and the high-osmolarity glycerol-mitogen-activated protein kinase cascade are likely to be involved in the signaling pathway of oxidative stress and osmotic stress in regulation of DOG2.