How budding yeast sense and transduce the oxidative stress signal and the impact in cell growth and morphogenesis.

The eukaryotic microorganism Saccharomyces cerevisiae is a current model system in which to study the signal transduction pathways involved in the oxidative stress response. In this review we present the current evidence demonstrating that in S. cerevisiae several MAPK and signalling routes participate in this response (PKC1-MAPK, TOR, RAS-PKA-cAMP). The signalling processes converge in the activation of a number of transcription factors (Yap1, Skn7, Rlm1, Msn2/Msn4, Sfp1, among others) required for the expression of certain genes involved in the oxidative stress response. Another important output of these signalling pathways is the actin cytoskeleton, a known target for oxidation and whose organisation needs to be tightly controlled since it is essential for the integrity of the cell. We know about the existence of different levels of cross-talk between these signalling pathways, which gives strength to the enormous importance of keeping a correct redox homeostasis in cells. S cerevisiae maintains a safeguard mechanism assuring that cells always respond properly to oxidation, by means of mechanisms described in the current review.