OCE-PRF: Sink or swim: how have transitions between land and sea affected the evolution and ecology of plant-fungal associations?

海草是全球沿海生态系统中的海洋植物和动力源。有时被称为“植物世界的鲸鱼”，海草是从入侵并适应海洋的陆地植物祖先进化而来的。在陆地上，真菌被认为是植物的朋友和敌人。事实上，真菌之间的友谊对于成功地将植物转移到陆地上至关重要。然而，人们对真菌在海洋中的作用或与海洋植物有关的情况知之甚少。拟议的工作将增加对海洋真菌生物学和海洋植物-真菌相互作用的知识。这项工作的目标包括植物和真菌伙伴的观点，也可以为海草的恢复工作提供参考。来自STEM代表性不足群体的本科生实习生将在整个工作过程中得到指导，并鼓励他们开展自己的相关研究项目。与这项工作相关的实验结果和核心主题将被改编成儿童阅读和评论的开放获取期刊《青年思维的前沿》。该项目的目标是利用公开获得的数据、依赖培养和不依赖培养的方法(1)评估海草的进化历史和遗传潜力，以与丛枝菌根真菌(AMF)形成联系，丛枝菌根真菌是一组对植物向陆地移动很重要的真菌，(2)描述以前培养的海草相关真菌的表型和功能多样性，以及(3)比较海草相关真菌的基因组与陆地近亲的基因组，以确定与陆地向海洋过渡有关的适应，并预测它们在与海草有关时的生态作用。将搜索海草和近亲的基因组和转录本，以寻找形成AMF关联所需的基因，然后将其置于系统发育的背景下。实验将测量海草真菌分离物(来自手边的分离物收集)对模拟海洋压力的一系列条件的耐受性。转录分析将被用来识别与胁迫耐受性相关的基因，这些基因可能与海洋中的生活有关，也可能在共生期间减轻植物毒素的作用。最后，基因组和超基因组组装的基因组将被放入真菌生命树，然后相互比较，并与从公共数据库中获得的陆地近亲的基因组进行比较，以揭示对其生态的洞察。真菌对于植物向陆地的移动至关重要，了解回到海洋生态系统可能如何影响植物-真菌关系可能会对我们对真菌共生的进化、生态和维护的理解产生革命性的影响。这一奖项反映了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。

Seagrasses are marine plants and powerhouses in coastal ecosystems globally. Sometimes referred to as the “whales of the plant world”, seagrasses evolved from a land plant ancestor that invaded and then adapted to the sea. On land, fungi are known to be plant friends and foes. In fact, fungal friendships were critical to the successful movement of plants onto land. However, little is known about the roles of fungi in the ocean or when associated with marine plants. The proposed work will increase knowledge of marine fungal biology and marine plant-fungal interactions. With goals including the perspectives of both plant and fungal partners, this work may also inform seagrass restoration efforts. Undergraduate interns from groups underrepresented in STEM will be mentored throughout this work and encouraged to undertake their own related research projects. Experimental results and core topics related to this work will be adapted for Frontiers for Young Minds, an open-access journal read and reviewed by kids. The goals of this project are to use publicly available data, culture-dependent and culture-independent methods (1) to assess the evolutionary history and genetic potential of seagrasses to form associations with arbuscular mycorrhizal fungi (AMF), a group of fungi important for the movement of plants onto land, (2) to characterize the phenotypic and functional diversity of previously cultured seagrass-associated fungi, and (3) to compare the genomes of seagrass-associated fungi to those of terrestrial relatives to identify adaptations related to land to sea transitions and predict their ecological roles when associated with seagrasses. The genome and transcriptomes of seagrasses and close relatives will be searched for genes required to form AMF associations and then placed in a phylogenetic context. Experiments will measure the tolerance of seagrass fungal isolates (from an in-hand isolate collection) to a range of conditions that mimic marine stresses. Transcriptomic analyses will be used to identify genes correlated with stress tolerance that may relate to living in the ocean and which may also play a role in alleviation of phytotoxins during symbiosis. Finally, genomes and metagenome-assembled genomes will be placed into the fungal tree of life and then compared with each other and with the genomes of close land relatives obtained from public databases to reveal insights into their ecology. Fungi were critical for the movement of plants onto land and understanding how a shift back into the marine ecosystem may have affected plant-fungal relationships could be transformative for our understanding of the evolution, ecology, and maintenance of fungal symbioses.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.