Meeting Abstract
Many insects go through diapause, a stage similar to hibernation, to survive winter months. During these months, insulin signaling decreases, but the importance of this pathway in overall diapause regulation is unclear. Few studies have investigated the role of insulin signaling in diapause, and further studies are needed to understand the biochemical and physiological changes that take place during diapause. Our previous studies showed that when exposed to fluctuating temperatures during diapause, alfalfa leafcutting bees, Megachile rotundata, have increased survival. Our hypothesis is that during the high temperature period, insulin signaling and oxidative stress repair mechanisms are able to function, leading to increased survival. To test this hypothesis, M. rotundata were overwintered in either a lab setting at a constant 4˚C or in the field in naturally fluctuating temperatures. Expression of target genes in the insulin signaling pathway was measured using quantitative PCR. Our prediction was that bees reared in the field would have higher expression of target genes throughout overwintering compared to bees reared in the lab at constant low temperatures. Gene expression data was analyzed with qbase+ software and normalized to expression of three reference genes. Our results showed a trend supporting our hypothesis, with bees overwintered in the field having higher expression than bees overwintered in the lab. Further analysis will be done to verify the significance of these trends. Currently farmers are unable to assess the health of overwintering M. rotundata, leading to high mortality rates from improper storage conditions. By understanding how the insulin signaling pathway changes in overwintering bees, genes from this pathway could be used as biomarkers for healthy bees.
