Dryophytes chrysoscelis Transcriptome or Gene expression

Cope's gray treefrog, Dryophytes chrysoscelis withstands the physiological challenges of corporeal freezing partly by accumulating cryoprotective compounds of hepatic origin, including glycerol, urea and glucose. We hypothesized that expression of genes related to cryoprotectant mobilization and stress tolerance would be differentially regulated in response to cold. Using high throughput RNA sequencing, RNA Seq, a hepatic transcriptome was generated and gene expression was compared among frongs that were warm-acclimated, cold-acclimated, and frozen. This study is the first to report transcriptomic responses to low temperature exposure in a freeze tolerant vertebrate. The hepatic transcriptome of D. chrysoscelis is responsive to cold and freezing. Transcriptomic regulation of genes related to particular pathways, such as glycerol biosynthesis, were not all regulated in parallel. The physiological demands associated with cold and freezing as well as the transcriptomic responses observed in this study are shared with several organisms that face similar ecophysiological challenges, suggesting common regulatory mechanisms. The results have implications for understanding cryobiology, tissue cryopreservation, and ecophysiology.