Meeting Abstract
Juveniles of the spring field cricket, Gryllus veletis, survive internal ice formation (i.e. are freeze-tolerant) when acclimated under fall-like conditions, while summer-acclimated juveniles do not survive freezing (i.e. are freeze-sensitive). We compare freeze-tolerant and freeze-sensitive G. veletis to identify tissues damaged by freezing, and potential mechanisms that protect against or repair this injury. All crickets exhibit fat body damage after a freeze-thaw cycle, but the damage is severe and irreparable in freeze-sensitive crickets, while freeze-tolerant crickets repair the damage within two days of recovery. We identified metabolites that differed in concentration between freeze-tolerant and freeze-sensitive G. veletis via metabolomics analyses of hemolymph and fat body tissue, and identified differences gene expression via transcriptomics of fat body tissue from both groups of crickets. We screened metabolites accumulated by freeze-tolerant crickets for their ability to reduce fat body cell damage during ex vivo freeze treatments of excised tissue. We then augmented in vivo hemolymph concentrations of putative cryoprotectants via injection to determine if they enhanced the ability of whole crickets to survive freezing. These experiments provide a better understanding of the mechanisms that underlie insect freeze tolerance.
