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。南极昆虫具有独特的生存机制，包括能够忍受冷冻和大量脱水，即使失去70%的身体水分也能存活下来。如何做到这一点是感兴趣的不仅是了解昆虫的季节性适应和它们如何应对气候变化，但所采用的分子和生理机制可能会提供有价值的见解更一般的机制，可用于冷冻保存和长期存储的人体组织和器官移植和其他医疗应用。研究人员将研究负责从体内去除水分的蛋白质，细胞水平的结果，以及负责基因在人群之间的变化。该项目还将进一步推动NSF的目标，即向公众提供科学发现和培训新一代科学家。每年，一名K-12教师将成为实地小组的成员，并协助实地工作和与学校儿童及其教师的外联。教育推广工作包括在当地学校和全国教师会议上做报告，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有关的文章。此外，本科生和研究生将接受研究项目各方面的广泛培训，并获得包括发表科学论文和在国家会议上发表演讲在内的丰富经验。该项目侧重于破译使南极摇蚊Belgica anapartica在干燥的极地环境中生存的生理和分子机制。这种极端微生物是研究胁迫耐受性和当地地理适应机制的理想系统，其基因组最近已被测序。 该项目有三个重点领域：1）评估水通道蛋白的作用（水通道蛋白）通过研究脱水过程中它们的基因表达来快速去除体内的水分; 2）研究代谢抑制的机制和自噬的作用（细胞成分的受控分解）通过研究脱水过程中负责自噬的基因的表达，将其作为应激耐受的介质;和3）使用遗传学方法评估种群结构、基因流和与胁迫耐受性相关的生理性状的适应性变化，该方法利用该物种可用的基因组序列以及来自采样种群及其栖息地的生理和环境数据。

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.