Antifreeze proteins and cold adaptation in fish

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My research program focuses on fish antifreeze proteins and their genes: diversity,  evolution, mechanisms of action, physiological regulation, and commercialization. These proteins, present in a wide variety of fish species inhabiting polar and subpolar/temperate oceans, play an essential role in the colonization of such potentially lethal environments. The antifreeze proteins protect the fish from freezing by binding to and preventing the growth of ice crystals that may form within their body fluids. This effectively lowers the fish's freezing point to safe levels, and allows them to survive in lethal freezing environments. Antifreeze proteins also play a role in cold adaptation by stabilizing cell membranes at low temperatures: properties that are being explored for the preservation of mammalian cells and tissues for therapeutic applications. Research on antifreeze proteins has also led to the development of genes that could help improve the economic viability of finfish aquaculture in the Canadian Atlantic region. Over the next five years we will continue to examine in detail the various antifreeze proteins  that have been selected by nature to protect fish from freezing. There is a great deal that we do not know about these proteins and their role in freeze protection. For example despite 30 years of research on the well-described antifreeze from winter flounder we only recently discovered the presence of another "hyperactive" antifreeze protein that is 10-100 times more effective. This protein alone can explain the resistance of the fish to freezing. Future research will determine whether such highly active proteins can be found in other fish. Research will also be carried out to determine the functional role of the low activity antifreeze that is present in abundance in these flounder. Do they have a specialized function that differs from that of the hyperactive one?  Research is underway to isolate the hyperactive antifreeze genes. Once this has been accomplished we will be able to transfer them to Atlantic salmon and test the hypothesis that the hyperactive antifreeze alone can prevent fish from freezing.