Meeting Abstract
Periodic exposure to low temperature stress throughout an insect’s life cycle can lead to deleterious physiological effects known as chill injury. Chill injury is characterized by a variety of downstream physiological responses such as metabolic imbalance, disruptions in ion homeostasis, and oxidative stress. Interestingly, when chill-susceptible insects are exposed to brief pulses of increased temperature each day (fluctuating thermal regimes; FTR), survival increases dramatically. Previous assessments of transcriptomic-level responses to FTR, relative to constant chilling, in the alfalfa leafcutting Bee, Megachile rotundata show little overlap in expression profiles across life stages, suggesting discrete mechanisms driving the beneficial effects of FTR across developmental stages. Although gene expression across life stages is highly variable, several functional classes of differentially expressed transcripts were still shared across life stages, including those that suggest an oxidative stress response. Here we present assessments of total antioxidant activity, DNA/RNA damage, protein carbonylation, and lipid peroxidation between FTR and constant temperature exposure in both prepupae exposed to an extended overwintering and pupa exposed to a cold snap during spring development.
