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

地球上的所有生物，以及维持它们生存的环境，都是由共生相互作用形成的。这些相互作用在世界范围内都很重要，但它们对生活在极端环境中的生物尤其重要，例如陆地北极，在那里，多种多样但研究不足的共生真菌（真菌内生菌）生活在驱动生态系统过程的健康植物和地衣中。真菌内生菌是高度多样化的，代表了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，这些压力包括北极固有的压力，以及与地球变暖相关的迅速而普遍的环境变化。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，提供内生菌群落如何随时间变化的信息，并测试共生群落如何对环境因素敏感的预测，这对了解广大北极地区及其他地区的生物多样性动态具有重要意义。该项目的科学目标与对下一代生物多样性科学家的包容性培训和多样化的承诺并行，同时为科学、教育和社会做出广泛贡献。总体而言，该项目将通过发现多样性，跟踪其在广泛的地理，环境和时间尺度上的环境敏感性，并为加强STEM国家资源相关的培训，教育和推广做出贡献，从而为北美北极的生物资源提供新的见解。研究小组将进行两次实地活动，以测试有关内生菌多样性、群落组成和分布的预测，这些预测跨越了北美东部和西部所有主要北极亚带的横断面。内生菌群落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进行检测。通过对过去100年来在同一地点采集的植物和地衣标本室标本中的内生菌进行调查，利用最近验证的方法来获取保存的宿主组织中的内生菌群落，将这些野外收集的与现场和标本相关的数据进行背景化。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的新工具中，并建立一个基于20多年全球采样的框架。最后，基因组学、系统基因组学和种群基因组学分析将用于探索内生菌和相关真菌的多样性，重点关注参与这些重要共生的最多样化的谱系。通过这些努力，该项目将生成和公开各种各样的新数据、生物多样性信息学工具、协议、标本、外展活动、教育模块和与广泛学科相关的培训。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值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.