Collaborative Research: Leveraging historical collections and new surveys to characterize foundational shifts in vital symbioses in the threatened Arctic

地球上所有的生物，以及维持它们生存的环境，都是由共生互动塑造的。这些相互作用在世界范围内都很重要，但对于生活在陆地北极等极端环境中的生物来说尤其重要，在那里，各种但未被充分研究的共生真菌(真菌内生真菌)生活在推动生态系统过程的健康植物和地衣中。真菌内生菌种类繁多，占地球上未被发现的真菌生物多样性的很大一部分。它们在塑造宿主对环境压力的反应方面很重要，环境压力包括北极固有的压力以及与我们星球变暖相关的快速和普遍的环境变化。该项目将发现和绘制北极标志性植物和地衣中真菌内生菌的多样性，提供关于内生菌群落如何随着时间的变化而变化的信息，并测试关于共生群落如何对环境因素敏感的预测，这将对理解广大北极地区和其他地区的生物多样性动态产生影响。该项目的科学目标与致力于包容性地培训和多样化下一代生物多样性科学家，同时广泛地为科学、教育和社会做出贡献的承诺是一致的。总体而言，该项目将通过发现多样性，在广泛的地理、环境和时间尺度上跟踪其环境敏感性，并为加强STEM国家资源的相关培训、教育和推广，对北美北极的生物资源提供新的洞察。研究小组将进行两次实地活动，以测试对横跨北美东部和西部所有主要北极亚区的横断面上的内生植物多样性、群落组成和分布的预测。将通过基于培养和无培养的下一代测序方法在代表性植物和地衣中检测内生菌群落。这些现场采集的与现场和标本相关的数据将通过对过去100年在这些相同地点收集的植物和地衣标本中的内生菌进行调查，利用最近被验证的方法来访问保存的宿主组织中的内生菌群落。新发现的内生菌的DNA序列将被整合到绘制地球进化史和生物多样性图的新工具中，其框架基于20多年的全球采样。最后，基因组、系统基因组和种群基因组分析将用于探索内生菌和相关真菌的多样性，重点放在参与这些重要共生的最多样化的谱系上。通过这些努力，该项目将生成并公开与广泛学科相关的各种新数据、生物多样性信息学工具、协议、标本、推广活动、教育模块和培训。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

All living things on Earth, and the environments that sustain them, are shaped by symbiotic interactions. These interactions are important worldwide, but they are especially vital for organisms that live in extreme environments such as the terrestrial Arctic, where diverse but understudied symbiotic fungi (fungal endophytes) live inside the healthy plants and lichens that drive ecosystem processes. Fungal endophytes are hyperdiverse and represent a large fraction of Earth’s undiscovered fungal biodiversity. They are important in shaping their hosts’ responses to environmental stresses, including those intrinsic to the Arctic as well as the rapid and pervasive environmental changes associated with the warming of our planet. This project will discover and chart the diversity of fungal endophytes in iconic plants and lichens of the Arctic, provide information on how communities of endophytes have changed over time, and test predictions about how symbiotic communities are sensitive to environmental factors, with implications for understanding biodiversity dynamics in the vast Arctic region and beyond. The scientific aims of the project parallel a commitment to inclusively training and diversifying the next generation of biodiversity scientists while contributing broadly to science, education, and society. Overall the project will provide new insight into the biological resources of the North American Arctic by discovering diversity, tracking its environmental sensitivity over broad geographic, environmental, and temporal scales, and contributing to training, education, and outreach relevant to strengthening national resources in STEM.The research team will conduct two field campaigns to test predictions regarding endophyte diversity, community composition, and distributions along transects that span all major Arctic subzones in eastern and western North America. Endophyte communities will be detected in representative plants and lichens via culture-based and culture-free, next-generation sequencing approaches. Field- and specimen-related data from these field collections will be contextualized by surveys of endophytes in herbarium specimens of plants and lichens collected over the past 100 years at these same sites, leveraging a recently validated approach for accessing endophyte communities in preserved host tissues. DNA sequences for newly discovered endophytes will be integrated into new tools for mapping Earth’s evolutionary history and biodiversity, with a framework based on more than 20 years of global sampling. Finally, genomic, phylogenomic, and population-genomic analyses will be used to explore diversification of endophytes and related fungi, with a focus on the most diverse lineages that engage in these important symbioses. Through these endeavors the project will generate and make public diverse new data, biodiversity informatics tools, protocols, specimens, outreach activities, educational modules, and training relevant to a wide array of disciplines.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.