3.5 Cross-temperature differential KEGG pathway expression
To capture shared and contrasting patterns at the level of gene- pathways, we examined whole KEGG pathway expression. We compared whole KEGG pathway expression in two pairwise comparisons, control vs.mild heat and mild vs. high heat, because these comparisons represent a stepwise temperature induction. Overall, mild heat resulted in down-regulation of pathways related to genetic information processing in heat-tolerant, B. calyciflorus s.s., and up-regulation of metabolic related pathways in the heat-sensitive, B. fernandoi . More specifically, pathways “ribosome”, “proteasome”, and “oxidative phosphorylation” were down-regulated under mild heat exposure for B. calyciflorus s.s. and up-regulated for B. fernandoi (Figure 5A, Figure S5, S6). In general, high heat caused up-regulation of pathways related mainly to metabolism such as carbohydrate metabolism and lipid metabolism and down-regulation of pathways related to signal transduction for the heat-tolerant B. calyciflorus s.s. (Figure 5B, Figure S7). The opposite was observed for the heat-sensitive, B fernandoi , in which pathways related to signal transduction were up-regulated, while pathways related to , carbohydrate and lipid metabolism were down-regulation under high heat. Genes involved in meiosis pathway were also up-regulated under high heat, while genes involved in “ribosome” pathway were down-regulated for this species (Figure 5B, Figure S8).