Profiling oxidative stress in Saccharomyces cerevisiae by oxidation of transcription factor Swi6p

ABSTRACT: Cell cycle sensing of oxidative stress in Saccharomyces cerevisiae by oxidation of a specific cysteine residue in the transcription factor Swi6p. Yeast cells begin to bud and enter S phase when growth conditions are favourable during G1 phase. When subjected to oxidative stress, cells arrest at G1 delaying entry into the cell cycle allowing repair of cellular damage. Hence, oxidative stress sensing is coordinated with the regulation of cell cycle. We identified a redox sensing cysteine residue in the cell-cycle regulator of Saccharomyces cerevisiae, Swi6p, at position 404. Mutation of Cys404 to alanine abolished the ability of the cells to arrest at G1 upon treatment by lipid hydroperoxide. By constructing a truncated form of Swi6p, the Cys404 residue was found to be oxidised when cells were subjected to the oxidant. Furthermore, microarray analysis revealed that mutation of Cys404 to alanine led to loss of suppression of G1-cyclins CLN1 and PCL1 when the cells were exposed to lipid hydroperoxide. In conclusion, oxidation of Cys404 serves as a molecular sensor of oxidative stress and inhibits entry into the cell cycle by suppression of G1-cyclin expression. We used a gene expression approach to assess the involvement of Cys404 in oxidative stress by mutating this residue to alanine in order to study whether it contributes to Swi6p, a transcriptional factor, function for redox regulation of the cell cycle. Wild type, swi6-deletant, and swi6 C404A-mutated yeast cells were treated with either linoleic acid hydroperoxide (LoaOOH) or control. Three replicates per group/treatment.

ORGANISM(S): Saccharomyces cerevisiae

SUBMITTER: Ruby Lin 

PROVIDER: E-GEOD-18334 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress