RUI: Aquaporins and Osmoregulation in a Freeze-Tolerant Amphibian

RUI：耐冻两栖动物中的水通道蛋白和渗透调节

• 批准号: 0517301
• 负责人: David Goldstein
• 金额: $ 42万
• 依托单位: Wright State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-08-01 至 2010-01-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0517301&HistoricalAwards=false
• 关键词: RUI; Aquaporins; Osmoregulation; Freeze; Tolerant

Although people dream of being able to freeze whole bodies and later return them to life, currently successful biomedical cryopreservation is restricted to relatively small structures like blood or embryos. However, there are animals, including several amphibians and reptiles, that survive northern winters in part by an ability to tolerate being frozen. This research will examine the physiological mechanisms responsible for freeze tolerance in one of those species, Cope's gray treefrog. This frog is unusual among freeze-tolerant vertebrates in that it accumulates glycerol in its body fluids as a cryoprotective agent; glycerol is also commonly used in biomedical preservative solutions. Specific questions to be addressed are how glycerol moves in and out of tissues of the treefrogs as they acclimate to cold and actually freeze, and how the glycerol movement is related to the distribution of water among tissues, which is critical to preventing ice formation inside cells where it would lead to lethal damage. In particular, experiments will investigate the role of aquaporins in accomplishing that glycerol and water movement. Aquaporins are proteins known to form passageways that allow water and, sometimes, other small molecules like glycerol to cross cell membranes, and it is hypothesize that they are critical to freeze tolerance. The objectives are to enhance the understanding of this fascinating natural phenomenon, and to use a natural model of freeze tolerance to elucidate principles that can be applied to biomedical cryopreservation. In the process, this work will provide training to undergraduate students at multiple levels of analysis, from principles of comparative biology to whole animals and molecular biology. This training will encourage integrative thinking and application of diverse methods to the study of animal physiology.

尽管人们梦想能够冻结整个身体并随后将它们恢复生命，但目前成功的生物医学冷冻保存仅限于相对较小的结构，例如血液或胚胎。 但是，有一些动物，包括几种两栖动物和爬行动物，它们在北方冬季幸存下来，部分原因是耐受冻结的能力。 这项研究将检查负责在其中一种物种Cope的Grey Treefog中冻结耐受性的生理机制。 这种青蛙在耐热的脊椎动物中是不寻常的，因为它作为冷冻保护剂积累了体液中的甘油。甘油也通常用于生物医学防腐剂溶液中。 要解决的具体问题是甘油在适应寒冷并冻结的树蛙的组织中进出了如何运动，以及甘油运动与组织之间水之间的分布有关，这对于预防细胞内部的冰形成至关重要。 特别是，实验将研究水通道蛋白在完成该甘油和水运动中的作用。 水通道蛋白是已知的蛋白质，可以形成通道，有时会允许水，有时还可以允许其他小分子（如甘油）越过细胞膜，并且假设它们对于冻结耐受性至关重要。 这些目标是增强对这种迷人的自然现象的理解，并使用冻结的自然模型来阐明可以应用于生物医学冷冻保存的原理。 在此过程中，这项工作将为从比较生物学到整个动物和分子生物学的原则进行多个分析的本科生提供培训。 该培训将鼓励综合思考和应用各种方法在动物生理学研究中。