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).