Collaborative Research: Winter Survival Mechanisms and Adaptive Genetic Variation in an Antarctic Insect

极地地区是沙漠，不仅寒冷，而且缺乏免费的水。南极昆虫有独特的生存机制，包括忍受冰冻和广泛脱水的能力，在失去70%的身体水分的情况下存活下来。如何做到这一点不仅对了解昆虫的季节适应性及其对气候变化的反应感兴趣，而且所采用的分子和生理机制可能为更一般的机制提供有价值的见解，这些机制可能被用于人体组织和器官的冷冻保存和长期储存，以供移植和其他医疗应用。研究人员将研究负责将水分从体内排出的蛋白质、细胞水平的影响，以及负责的基因在不同人群之间的差异。该项目还将进一步实现国家科学基金会的目标，即让公众获得科学发现，并培养新一代的科学家。每年，一名K-12教师将成为实地小组的一员，协助实地工作，并向学校的孩子和他们的老师伸出援手。教育推广工作包括在当地学校和全国教师会议上发表演讲，在网站上提供课程计划和播客，并继续在教育期刊上发表与这项研究相关的文章。此外，本科生和研究生将在研究项目的各个方面接受广泛的培训，并获得包括发表科学论文和在国家会议上发言在内的丰富经验。该项目的重点是破译使南极蠓在干燥的极地环境中生存的环境压力和大部分身体水分的损失的生理和分子机制。这种极端微生物是研究耐受性和局部地理适应机制的理想系统，其基因组最近已被测序。本项目有三个重点领域：1)通过研究水通道蛋白（水通道蛋白）在脱水过程中基因的表达来评估水通道蛋白在体内快速脱除水分中的作用；2)通过研究脱水过程中自噬相关基因的表达，探讨代谢抑制的机制以及自噬（细胞成分的受控分解）作为应激耐受介质的作用；3)利用遗传方法，利用该物种可用的基因组序列，结合采样种群及其栖息地的生理和环境数据，评估与胁迫耐受性相关的生理性状的种群结构、基因流和适应性变化。

Polar regions are deserts that are not only cold but also lack access to free water. Antarctic insects have unique survival mechanisms including the ability to tolerate freezing and extensive dehydration, surviving the loss of 70% of their body water. How this is done is of interest not only for understanding seasonal adaptations of insects and how they respond to climate change, but the molecular and physiological mechanisms employed may offer valuable insights into more general mechanisms that might be exploited for cryopreservation and long-term storage of human tissues and organs for transplantation and other medical applications. The investigators will study the proteins that are responsible for removing water from the body, cell level consequences of this, and how the responsible genes vary between populations. The project will also further the NSF goals of making scientific discoveries available to the general public and of training new generations of scientists. Each year a K-12 teacher will be a member of the field team and assist with fieldwork and outreach to school children and their teachers. Educational outreach efforts include presentations at local schools and national teacher meetings, providing lesson plans and podcasts on a website, and continuing to publish articles related to this research in education journals. In addition, undergraduate and graduate students will receive extensive training in all aspects of the research project with extended experiences that include publication of scientific papers and presentations at national meetings.This project focuses on deciphering the physiological and molecular mechanisms that enable the Antarctic midge Belgica antarctica to survive environmental stress and the loss of most of its body water in the desiccating polar environment. This extremophile is an ideal system for investigating mechanisms of stress tolerance and local geographic adaptations and its genome has recently been sequenced. This project has three focal areas: 1) Evaluating the role of aquaporins (water channel proteins) in the rapid removal of water from the body by studying expression of their genes during dehydration; 2) Investigating the mechanism of metabolic depression and the role of autophagy (controlled breakdown of cellular components) as a mediator of stress tolerance by studying expression of the genes responsible for autophagy during the dehydration process; and 3) Evaluating the population structure, gene flow, and adaptive variation in physiological traits associated with stress tolerance using a genetic approach that takes advantage of the genomic sequence available for this species coupled with physiological and environmental data from the sampled populations and their habitats.