Fig. 3.

Interspecies differences between Saccharomycetes in stress responsiveness of the membrane protein regulon. Each trace represents a cumulative distribution function (F[x]) of the difference between Saccharomyces cerevisiae and S. paradoxus in induction of gene expression after stress exposure, relative to expression in the rich-medium YPD (Tirosh et al. 2006). In each panel, the x axis reports log₂(expression in stress_Scer/expression in YPD_Scer) − log₂(expression in stress_Spar/expression in YPD_Spar). The blue trace reports the distribution across all genes and the red trace reports that across the membrane protein regulon (fig. 1 and supplementary table 1, Supplementary Material online). (A) Switch to glycerol as the carbon source, 20-min time point. (B) Nitrogen starvation, 45-min time point. (C) Treatment with methyl methanesulfonate, 1.5-h time point. P, one-sided P value from a Wilcoxon test comparing expression changes in the membrane regulon to changes across the genome.