IPY: A Community Genomics Investigation of Fungal Adaptation to Cold

IPY：真菌适应寒冷的群落基因组学研究

• 批准号: 0632332
• 负责人: Donald Taylor
• 金额: $ 74.37万
• 依托单位: University of Alaska Fairbanks Campus
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-07-01 至 2013-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0632332&HistoricalAwards=false
• 关键词: IPY; Community; Genomics; Investigation; Fungal

IPY FY 06 Life in the Cold and Dark ARC- 0632332 TaylorThis research will conduct a large-scale community genomics analysis of fungi in the Arctic to provide insights into the diversity, metabolism, and seasonal dynamics of cold-adapted fungi. Fungi survive, reproduce, and carry out diverse biogeochemical transformations in arctic soils that are extremely cold, often dry, and mostly snow covered. Clearly, these fungi are adapted to extremes of cold and dark. Yet our knowledge of the identities and activities of these cold-adapted fungi is negligible. The goal of this work is to better understand fungal adaptation to cold, and will accomplish this by determining which species occur in the coldest climates, and which species are metabolically active at the coldest temperatures. While focused on adaptation, the project will also inform ecosystem ecology. Polar regions provide significant ecosystem services to society, including climate regulation. The ongoing changes in polar regions, which are often more rapid and of larger magnitude than in lower latitudes, are having uncertain effects on ecosystem services, particularly positive and negative feedbacks to global warming. Two key, interrelated uncertainties are 1) how vegetation patterns will change, and how these changes will feed back to climate, and 2) how soil carbon pools will change with changing patterns of permafrost, soil temperatures and vegetation cover. Mycorrhizal fungi strongly influence plant growth and community structure through their roles as ubiquitous symbionts of arctic plants. Decomposer fungi strongly influence rates and patterns of respiratory carbon release to the atmosphere, as well as mineralization and immobilization of the limiting nutrients nitrogen and phosphorus. Hence, soil-dwelling fungi are central players in both vegetation change and carbon dynamics, and therefore, uncertainties about the roles of fungi in polar ecosystem contribute to overall uncertainties about climate change and the future of polar regions. The three specific objectives in the research proposed are to: (1) reveal which fungal species are most adapted to extreme arctic environmental conditions by characterizing the changes in fungal communities along three latitudinal gradients (NAAT, Eurasia, Spitsbergen) using high-throughput, DNA-based clone-library sequencing; (2) test whether predicted changes in climate will select for more southerly or northerly fungal communities using reciprocal soil warming and cooling experiments and clone-library sequencing at the Toolik Lake and Bonanza Creek Long Term Ecological Research (LTER) sites; and (3) characterize the components of the fungal communities that are metabolically active in both summer and winter using a newly developed RNA-based library sequencing method. By revealing which species and guilds of fungi are most active in different habitats, in different seasons, and under different temperature regimes, the work will unveil novel insights into processes underling winter respiration and nutrient cycling in the Arctic. The study is pan-Arctic and international, both in geographic extent and in the collaborating consortium of US, Russian, and UK scientists. At the local level it will educate elementary school students about fungi and their ecology, and will support graduate education and scientific exchange among multiple countries.

2006财政年度寒冷和黑暗中的生活 这项研究将对北极地区的真菌进行大规模的群落基因组学分析，以深入了解适应寒冷的真菌的多样性、代谢和季节动态。真菌生存，繁殖，并在北极土壤中进行各种生物地球化学转化，这些土壤非常寒冷，通常干燥，大部分被雪覆盖。显然，这些真菌适应极端的寒冷和黑暗。然而，我们对这些冷适应真菌的身份和活动的了解是微不足道的。这项工作的目标是更好地了解真菌对寒冷的适应，并将通过确定哪些物种出现在最冷的气候中，以及哪些物种在最冷的温度下代谢活跃来实现这一目标。在关注适应的同时，该项目还将为生态系统生态学提供信息。极地地区为社会提供重要的生态系统服务，包括气候调节。极地地区正在发生的变化往往比低纬度地区更快、规模更大，对生态系统服务产生了不确定的影响，特别是对全球变暖的积极和消极反馈。两个关键的、相互关联的不确定性是：1）植被模式将如何变化，以及这些变化将如何反馈到气候; 2）土壤碳库将如何随着冻土、土壤温度和植被覆盖模式的变化而变化。菌根真菌作为北极植物的共生体，对植物的生长和群落结构有着重要的影响。分解真菌强烈影响呼吸碳释放到大气中的速率和模式，以及限制营养素氮和磷的矿化和固定。因此，土壤真菌是植被变化和碳动力学的核心参与者，因此，真菌在极地生态系统中作用的不确定性导致了气候变化和极地未来的整体不确定性。本研究的三个具体目标是：（1）通过描述真菌群落在沿着三个纬度梯度上的变化，揭示哪些真菌物种最适应极端的北极环境条件（NAAT，Eurasia，Spitsbergen）使用高通量的基于DNA的克隆文库测序;（2）利用土壤升温和降温的相互作用实验，测试预测的气候变化是否会选择更南或更北的真菌群落，库测序在图利克湖和博南扎溪长期生态研究（LTER）网站;和（3）的特点，在夏季和冬季代谢活跃的真菌群落的组成部分，使用新开发的RNA为基础的文库测序方法。通过揭示真菌的哪些物种和公会在不同的栖息地、不同的季节和不同的温度条件下最活跃，这项工作将揭示北极冬季呼吸和营养循环过程的新见解。这项研究是泛北极和国际性的，无论是在地理范围内还是在美国，俄罗斯和英国科学家的合作联盟中。在地方一级，它将教育小学生有关真菌及其生态学，并将支持研究生教育和多国之间的科学交流。