Data from: Ambient temperature-mediated changes in hepatic gene expression of a mammalian herbivore (Neotoma lepida)

Herbivores regularly ingest natural toxins produced by plants as a defence
against herbivory. Recent work suggests that compound toxicity is
exacerbated at higher ambient temperatures. This phenomenon, known as
temperature-dependent toxicity (TDT), is the likely result of decreased
liver function at warmer temperatures; however, the underlying cause of
TDT remains speculative. In the present study, we compared the effects of
temperature and dietary plant toxins on differential gene expression in
the liver of an herbivorous rodent (Neotoma lepida), using
species-specific microarrays. Expression profiles revealed a greater
number of differentially expressed genes at an ambient temperature below
the thermal neutral zone for N. lepida (22°C) compared to one within
(27°C). Genes and pathways upregulated at 22°C were related to growth and
biosynthesis, whereas those upregulated at 27°C were associated with
gluconeogenesis, apoptosis and protein misfolding, suggestive of a
stressed state for the liver. Additionally, few genes associated with
xenobiotic metabolism were induced when woodrats ingested plant toxins
compared to nontoxic diets, regardless of temperature. Taken together, the
results highlight the important role of ambient temperature on gene
expression profiles in the desert woodrat. Temperatures just below the
thermal neutral zone might be a favourable state for liver metabolism.
Furthermore, the reduction in the number of genes expressed at a
temperature within the thermal neutral zone indicates that liver function
may be reduced at temperatures that are not typically considered as
thermally stressful. Understanding how herbivorous mammals will respond to
ambient temperature is imperative to accurately predict the impacts of
climate change.