Fig. 4

Transcriptome reorganization for thermal adaptation. a Principal component analysis based on individual microarrays. The main four components (P1–P4) are shown. Color variation filled in the circles represents differences among the strains (Anc, 41B, 43B and 45 L), as indicated. The letters hs, r, and e, which are indicated within the circles, represent gene expression conditions, heat shock responsive states, and steady states at regular and evolution-stimulating (high) temperatures, respectively. The weights of each PC are indicated. Pale gray and pink lines illustrate the two zones of the steady expression at the regular temperature and the responsive expression, respectively. b Gene categories and gene regulation significantly contributed to the main PCs. The top 5 % of the genes (439 genes) weighted on each PC were subjected to analysis. Color bars indicate the statistical significance in log-scaled p values obtained using binomial tests with Bonferroni corrections. Asterisks indicate either non-synonymous single-nucleotide substitutions or InDel mutations that occurred during evolution