A High-coverage Ancient Genome for Analyzing Arctic Adaptation Mechanisms – the Steller’s Sea Cow Case

用于分析北极适应机制的高覆盖率古代基因组——斯特勒海牛案例

• 批准号: 418575273
• 负责人: Professor Dr. Michael Hofreiter
• 金额: --
• 依托单位: Rudolf-Schönheimer-Institut für Biochemie
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2019
• 资助国家: 德国
• 起止时间: 2018-12-31 至 2022-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/418575273?language=en
• 关键词: coverage; Ancient; Genome; Analyzing; Arctic

How organisms respond to climatic and environmental changes is a topic of considerable interest, and considerable effort is spent to explore different scenarios about adaptation. While extant Sirenians (dugongs, manatees) are tropical and subtropical animals, who cannot survive for long in cold or cool water, their extinct relative, the Steller’s sea cow (H. gigas) inhabited cold waters from the northern hemisphere. Intriguingly, the protein that allows non-shivering heat production, UCP1, is missing in all Sirenians, including H. gigas. The mechanism, how H. gigas regulated its body temperature, is unknown. We propose to use the ancient genome of H. gigas for investigating specific traits of Pleistocene arctic adaptation. Recent advances in molecular biology and sequencing technologies made it possible to build an ancient DNA library and already sequence the H. gigas genome to 7.8 times. To have a close reference genome, we will sequence and de novo assemble the dugong genome. By deeper sequencing the H. gigas ancient genome (30 times), we will be able to perform comparative analyses between sea cow, dugong, and manatee and reveal the genetic basis of species-specific traits in H. gigas (e.g. body temperature regulation, lack of digits, increased body size, jaw morphology). Using the diploid genome, we have enough information to model the demographic history and measure the genetic influence of extinct H. gigas on recent Sirenians or vice versa. By sequencing the genome of a species, whose extinction was directly or indirectly driven by wasteful hunting, and assembling the genome of extant endangered relatives, this project will raise awareness on preserving resources, which are mistakenly perceived as "infinite".

生物体如何对气候和环境变化做出反应是一个相当感兴趣的话题，人们花费了相当大的努力来探索关于适应的不同情景。虽然现存的锡雷尼亚人(儒艮、海牛)是热带和亚热带动物，它们不能在冷水或冷水中生存很长时间，但它们已灭绝的近亲斯特勒海牛(H.gias)生活在北半球的冷水中。耐人寻味的是，所有锡里尼亚人，包括长臂猿在内，都缺少一种能够产生非颤抖热量的蛋白质UCP1。至于H.Gigas是如何调节其体温的，目前尚不清楚。我们建议利用巨藻的古老基因组来研究更新世适应北极的特定特征。分子生物学和测序技术的最新进展使人们有可能建立一个古老的DNA文库，并已经对巨藻基因组进行了7.8倍的测序。为了有一个紧密的参考基因组，我们将对儒艮基因组进行测序和重新组装。通过对巨型海牛古代基因组进行更深入的测序(30次)，我们将能够对海牛、儒艮和海牛进行比较分析，并揭示巨型海牛物种特有特征的遗传基础(例如，体温调节、缺少指头、体型增加、下巴形态)。利用二倍体基因组，我们有足够的信息来模拟人口学历史，并测量灭绝的千年虫对现代锡里纳人的遗传影响，反之亦然。通过对一个物种的基因组进行测序，该物种的灭绝是由浪费的狩猎直接或间接造成的，并组装现有濒危亲属的基因组，该项目将提高人们对保护资源的认识，这些资源被错误地认为是“无限的”。