Meeting Abstract
Rapid cold hardening (RCH) is a form of adaptive plasticity that allows insects to improve their cold tolerance in a short period of time (i.e. minutes to hours). RCH allows an organism to cope with sudden cold snaps and diurnal thermal cycles, which is especially important as thermal variability is projected to increase with climate change. Recent genetic evidence suggests that autophagy, a cell recycling process that breaks down damaged organelles and macromolecules, is involved in RCH. However, the physiological role of autophagy during RCH has not been examined. The objective of our study is to develop methods for quantifying autophagy during RCH in the common fruit fly, Drosophila melanogaster. Activation of cellular autophagy can be visualized with LysoTracker Red DND-99, a fluorescent dye that stains acidic lysosomic and autophagic vesicles. While this dye is commonly used as a qualitative marker of on/off autophagic processes in D. melanogaster, a reliable method to quantify autophagy across tissue types has not been developed. Here we optimize protocols to measure levels of autophagy in response to RCH and other stressors. Preliminary results indicate a significant increase in LysoTracker staining in the adult midgut in response to RCH followed by a brief cold shock, and current experiments are underway to expand these results to additional tissues and treatment conditions. Combining these protocols with genetic tools for studying autophagy in D. melanogaster, we will be able to further our understanding of the physiological processes that govern rapid adaptive plasticity to cold and other extreme conditions.
