Novel observations of "freeze resistance" and dynamic blue and green dorsal coloration in frozen and thawing Dryophytes chrysoscelis.

Freeze tolerant animals survive the winter by tolerating the freezing and thawing of up to 70% of body water and the respective cessation and resumption of essential functions including circulation and respiration during each freeze-thaw cycle. Cope's gray treefrog Dryophytes chrysoscelis is a freeze tolerant anuran that uses a system of cryoprotectants to prevent intracellular freezing and mitigate osmotic stress during freezing and thawing episodes. Morphological features were documented in D.

Repeated freeze-thaw cycles in freeze-tolerant treefrogs: novel interindividual variation of integrative biochemical, cellular, and organismal responses.

The freeze-tolerant anuran , Cope's gray treefrog, mobilizes a complex cryoprotectant system that includes glycerol, glucose, and urea to minimize damage induced by freezing and thawing of up to 65% of body water. In this species' eastern Northern American temperate habitat, oscillations of temperature above and below freezing are common; however, the effects of repeated freezing and thawing in this species are unstudied. The biochemical and physiological effects of repeated freeze-thaw cycles were therefore evaluated and compared with cold acclimation and single freeze-thaw episodes.

Hepatic transcriptome of the freeze-tolerant Cope's gray treefrog, Dryophytes chrysoscelis: responses to cold acclimation and freezing.

Background: 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 for D.

Postfreeze viability of erythrocytes from Dryophytes chrysoscelis.

Dryophytes chrysoscelis (formerly Hyla chrysoscelis, Cope's gray treefrog) is a freeze-tolerant anuran that accumulates glycerol and urea during cold acclimation and freezing. It is hypothesized that glycerol and urea function as cryoprotectants by minimizing osmotically induced cell damage during freezing and thawing, thereby improving the postfreeze viability of red blood cells (RBCs) when frozen in medium containing those solutes. To test this, erythrocytes were obtained from warm (22°C) and cold-acclimated (4°C) frogs and suspended in 280 mOsM phosphate-buffered saline (PBS).

The cryoprotectant system of Cope's gray treefrog, Dryophytes chrysoscelis: responses to cold acclimation, freezing, and thawing.

Cope's gray treefrog (Dryophytes chrysoscelis) is one of few freeze-tolerant frogs that mobilize glycerol as a cryoprotectant, yet cold and freezing-induced accumulation of this and other osmolytes has received little attention in this species. This study investigated the development of freeze tolerance in D. chrysoscelis, analyzing the response of the cryoprotectant system to cold acclimation, freezing, and thawing.