Antifreeze proteins and cold adaptation in fish

我的研究项目主要集中在鱼类抗冻蛋白及其基因：多样性，进化，作用机制，生理调节和商业化。这些蛋白质存在于生活在极地和亚极地/温带海洋的各种鱼类中，在这种潜在致命环境的定植中起着至关重要的作用。抗冻蛋白通过与鱼的体液结合并阻止冰晶的生长来保护鱼不被冻住。这有效地将鱼的冰点降低到安全水平，使它们能够在致命的冰冻环境中生存。抗冻蛋白还通过在低温下稳定细胞膜在冷适应中发挥作用：这些特性正在被用于保存哺乳动物细胞和组织的治疗应用。对抗冻蛋白的研究也导致了基因的发展，这些基因可以帮助提高加拿大大西洋地区鳍鱼养殖的经济可行性。在接下来的五年里，我们将继续详细研究大自然选择的各种防冻蛋白，以保护鱼类免受冷冻。我们对这些蛋白质和它们在冷冻保护中的作用还知之甚少。例如，尽管对冬季比目鱼的防冻剂进行了30年的研究，但我们最近才发现另一种“过度活跃”的防冻剂蛋白质的存在，其有效性是其10-100倍。单是这种蛋白质就能解释鱼为何能抵抗冰冻。未来的研究将确定是否可以在其他鱼类中发现这种高活性蛋白质。还将进行研究，以确定在这些比目鱼中大量存在的低活性防冻剂的功能作用。他们是否有不同于多动症患者的特殊功能？研究人员正在分离这种过度活跃的抗冻基因。一旦这项工作完成，我们就可以将它们转移到大西洋鲑鱼身上，并测试单靠这种活性极强的防冻剂就能防止鱼类冻僵的假设。

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.