Thermal hysteresis activity in the skin of the cunner, Tautogolabrus adspersus

• Published in: Canadian Journal of Zoology
• Main Authors: Valerio, P. F., Kao, M. H., Fletcher, G. L.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Canadian Science Publishing 1990
• Subjects: Newfoundland
• Online Access: http://dx.doi.org/10.1139/z90-156; http://www.nrcresearchpress.com/doi/pdf/10.1139/z90-156

Previous studies have shown that cunners, Tautogolabrus adspersus, remain inshore in marine waters around Newfoundland during the winter months, but are in a state of metabolic torpor, apparently surviving by undercooling without freezing. The present study reports the discovery of measurable levels of thermal hysteresis activity in aqueous extracts of winter cunner skin, but not in the blood plasma. The occurrence of a compound with thermal hysteresis activity indicates the presence of antifreeze polypeptides in the Labridae. This is of significant interest, since this family is mostly tropical in distribution, and has likely invaded northern waters in relatively recent times. The functional significance of skin thermal hysteresis activity is discussed in relation to the protective role of antifreeze compounds.