Environmental, hormonal and cellular correlates of thermal biology and adaptation in fish.

这项NSERC发现研究计划将研究甲状腺激素和应激蛋白(热休克蛋白，HSPs)的功能，以了解鱼类如何对不断变化的环境和极端环境(温度)做出反应。不管是人为原因还是自然原因，世界气候在过去50-100年里一直在变化，而且变得更加多变。淡水鱼是体温过高的动物(不能利用体内过程调节体温)，在身体上躲避不适宜居住的温度的能力受到限制，因此它们可能对气候变化的影响特别敏感。这个项目将研究湖面白鱼，一种冷水，温度敏感的鱼，在2-4°C发育，生活在深湖中，全年深水温度10-13°C。作为北美最具商业价值的淡水鱼，也是对我们的原住民非常重要的一种鱼，白鱼在经济和文化上都非常有价值。这一事实，再加上它们对温暖的温度敏感，以及在实验室中易于处理和饲养，使湖泊白鱼成为研究适应温度压力和不断变化的环境的理想物种。甲状腺激素是所有脊椎动物(脊椎动物)的关键代谢荷尔蒙，也是调节哺乳动物和其他恒温动物体温的基本因素。尽管如此，在鱼类和其他外温类动物中，甲状腺激素在调节新陈代谢方面的作用仍有待于研究，因为它与热生物学和压力有关。这项研究计划特别致力于了解甲状腺激素在热应激和适应温度变化中的作用，以及涉及的精确的细胞和生理(内部)机制。甲状腺激素在线粒体生物能量学和生物合成中的作用将在不同的温度条件下进行研究。这些研究将有助于更好地了解外温热生物学，并可能为甲状腺激素在吸热中的作用的进化提供洞察力。这项研究的一个关键方面是我研究萨斯喀彻温省野生白鱼种群的能力，这些种群生活在非常浅的湖泊中，在夏季的几个月里，这些湖泊白鱼经常达到湖泊白鱼的致命温度极限(23-25°C)。这些湖泊白鱼种群已经适应了这种物种通常所处的温度限制之外的生活。通过使用蛋白质组学方法直接比较萨斯喀彻温省浅水湖和深水湖鱼类的总蛋白质谱，我的研究团队将在细胞水平上确定参与热适应的关键系统。在NSERC发现计划的过程中，我和我的研究团队(3名研究生和8名本科生)将在我们对鱼类如何适应不断变化的环境的理解方面取得重大进展。最终，这项工作将提供一些必要的信息，帮助我们了解对温度敏感的鱼类如何适应并在不断变化的气候中生存。

This NSERC discovery research program will investigate the function of thyroid hormones and stress proteins (heat shock proteins, HSPs) to understand how fish respond to changing environments and environmental (temperature) extremes. Irrespective of the cause (human versus natural), the world’s climate has been changing over the past 50-100 years and has been more variable. Freshwater fish are ectotherms (unable to use internal processes to regulate body temperature) and restricted in their ability to physically escape inhospitable temperatures, thus they may be particularly sensitive to the effects of climate changes. This program will study lake whitefish, a cold water, thermally sensitive fish that develops at 2-4°C and lives in deep lakes with year round deep water temperatures of 10-13°C. As the most commercially fished, freshwater fish in North America and a fish of great importance to our First Nations People, whitefish are very valuable both economically and culturally. This fact, coupled with their sensitivity to warm temperatures and ease of handling and rearing in the laboratory, make lake whitefish an ideal species to study adaptation to thermal stress and changing environments. Thyroid hormones are key metabolic hormones in all vertebrates (animals with a backbone) and are fundamental in regulating body temperature in mammals and other endotherms. Despite this fact, the role of thyroid hormones in regulating metabolism as it relates to thermal biology and stress remains to be investigated in fish and other ectotherms. This research program specifically seeks to understand the function of thyroid hormones in thermal stress and adaptation to changing temperatures and the precise cellular and physiological (internal) mechanisms involved. The function of thyroid hormones in mitochondrial bioenergetics and biosynthesis under different thermal regimes will be investigated. These studies will lead to a better understanding of thermal biology in ectotherms and may offer insight into the evolution of the role of thyroid hormones in endothermy. One key aspect of this research is my ability to study wild populations of lake whitefish in Saskatchewan that are living in very shallow lakes which in the summer months routinely reach the lethal temperature limit (23-25°C) for lake whitefish. These populations of lake whitefish have adapted to living outside the temperature limits in which the species is normally found. By using a proteomic approach to make a direct comparison of the total protein profiles between fish in shallow lakes and those living in deep lakes in Saskatchewan, my research team will identify the key systems involved in thermal adaption at the cellular level. Over the course of this NSERC discovery program my research team (3 graduate and 8 undergraduate students) and I will make significant advances in our understanding of how fish adapt to changing environments. Ultimately, this work will provide some of the necessary information to help us understand how thermally sensitive fish may adapt and survive a changing climate.