Proteomic response to linoleic acid hydroperoxide in Saccharomyces cerevisiae.

Yeast AP-1 transcription factor (Yap1p) and the enigmatic oxidoreductases Oye2p and Oye3p are involved in counteracting lipid oxidants and their unsaturated breakdown products. In order to uncover the response to linoleic acid hydroperoxide (LoaOOH) and the roles of Oye2p, Oye3p and Yap1p, we carried out proteomic analysis of the homozygous deletion mutants oye3Δ, oye2Δ and yap1Δ alongside the diploid parent strain BY4743. The findings demonstrate that deletion of YAP1 narrowed the response to LoaOOH, as the number of proteins differentially expressed in yap1Δ was 70% of that observed in BY4743. The role of Yap1p in regulating the major yeast peroxiredoxin Tsa1p was demonstrated by the decreased expression of Tsa1p in yap1Δ. The levels of Ahp1p and Hsp31p, previously shown to be regulated by Yap1p, were increased in LoaOOH-treated yap1Δ, indicating their expression is also regulated by another transcription factor(s). Relative to BY4743, protein expression differed in oye3Δ and oye2Δ under LoaOOH, underscored by superoxide dismutase (Sod1p), multiple heat shock proteins (Hsp60p, Ssa1p, and Sse1p), the flavodoxin-like protein Pst2p and the actin stabiliser tropomyosin (Tpm1p). Proteins associated with glycolysis were increased in all strains following treatment with LoaOOH. Together, the dataset reveals, for the first time, the yeast proteomic response to LoaOOH, highlighting the significance of carbohydrate metabolism, as well as distinction between the roles of Oye3p, Oye2p and Yap1p.