CAREER: Integrative Physiology of Anoxia Tolerance in Turtles

所有动物在其一生中都受到环境压力的影响，对于水生栖息地的动物来说，氧气的可获得性可能是一个特别的问题，因为那里的溶解度低，对它的竞争很激烈。一种名为西方彩龟的动物已经进化出了在20摄氏度下完全缺氧30多小时，在3摄氏度下存活3个多月的能力，这比其他任何四足动物都要长。这种能力使彩绘海龟能够在野外氧气耗尽、冰雪覆盖的池塘中越冬。为了了解潜在的机制，这项研究使用最近测序的彩龟基因组来确定缺氧期间发生的基因表达变化，并将它们与已知发生的生理变化联系起来。它关注的是海龟的心脏，在其他脊椎动物中，它对缺氧极其敏感，包括人类。它还关注发展，因为幼龟比成年海龟对缺氧的耐受性更差。这项研究还探索了与处理大量乳酸负荷有关的过程，乳酸负荷累积到比任何其他动物都高的水平。这包括研究乳酸如何影响甲鱼的甲壳和心脏，以及乳酸如何在体内代谢。还有涉及圣路易斯动物园的教育部分，这将加强其现有的教育学徒计划之一，主要代表服务不足和代表性不足的少数族裔。它还支持一个促进公民科学的年度研讨会，该研讨会将为圣路易斯地区的科学家提供资源和机会，让他们与希望获得科学研究经验的高中生和大学生建立联系。这个项目的更广泛的影响将是为一个经济、生态和临床相关的问题提供重要的见解，即为什么一些动物比其他动物更耐缺氧。它还将增加学生对科学的参与，特别是比较动物生理学。

All animals are subject to environmental stress during their lives and oxygen availability may be a particular problem for animals in aquatic habitats, where solubility is low and competition for it is high. One animal, the Western painted turtle has evolved the capacity to survive complete oxygen deprivation, also called anoxia, for over 30 hours at 20°C and for more than three months at 3°C, which is longer than any other tetrapod. This ability allows the painted turtle to overwinter in oxygen-depleted, ice-covered ponds in the wild. To understand the underlying mechanisms, this research uses the recently sequenced painted turtle genome to determine the gene expression changes that occur during anoxia and to relate them to the physiological changes that are already known to occur. It focuses on the turtle's heart, which, in other vertebrates, is extremely sensitive to oxygen deprivation, including humans. It also focuses on development, because hatchling turtles are less tolerant of anoxia than adults. This research also explores processes related to the handling of the massive lactic acid loads, which accumulate to levels higher than seen in any other animal. This includes studies of how lactic acid affects the turtle shell and heart and how that lactic acid metabolized by the body. There is also educational component involving the St. Louis Zoo, which will enhance one of its existing educational apprenticeship program representing mostly underserved and underrepresented minorities. It also supports an annual workshop to promote civic science, which will provide resources and opportunities for St. Louis area scientists to connect with high school and college students looking to gain scientific research experience. The broader impacts of this project will be to provide important insights into an economically, ecologically, and clinically relevant problem, namely why some animals are more tolerant of oxygen deprivation than others. It will also increase student participation in the sciences, generally, and comparative animal physiology, specifically.