DISSERTATION RESEARCH: Assessing the Importance of Trophic Lability for Fungal Endophytism Using the Moss Dicranum scoparium and its Associated Fungi

植物是必不可少的，因为它们是陆地生态系统的主要碳源。 与人类和一般动物类似，植物也有不同的微生物群落，包括真菌。苔藓是北方、北极和高山植被的主要组成部分，这些植被受环境变化的影响最大。已知它们宿主不同的真菌群落，生活在植物组织（内生）内，如叶子，而不会引起任何可见的症状。内生真菌实际上可以以各种方式帮助活植物，包括改善营养吸收和保护免受病原体侵害。然而，真菌也被认为是死亡植物材料的熟练分解者。真菌在这些功能状态之间的转换可能是动态的，并可能受到非生物和生物因素的调节。了解这些功能转变发生的环境和机制将大大提高植物-真菌相互作用及其作为共生实体维持营养循环和生态系统功能的作用的知识。研究人员将参加各种外展活动，包括在北卡罗来纳州自然科学博物馆举行的年度达尔文日展览活动。这笔赠款将大大提高合作PI的博士学位。论文，并有助于一个成功的学术生涯的独立研究计划的发展。在此之前，研究人员已经研究了内生真菌物种及其在苔藓植物衰老梯度中的功能，使用创新的元转录组方法。虽然活跃的真菌物种被发现根据苔藓的衰老梯度的结构，几种真菌栖息在生活（顶部）和分解（底部）的植物部分，提供多个候选真菌物种研究共生和腐食之间的营养转换。研究人员将在纯培养物中分离出这些真菌中的一些，并将它们用于一项旨在量化焦点真菌菌株对活的和死的苔藓组织的影响的实验中。利用这些真菌与苔藓植物的共培养实验，该项目将表征苔藓对其相关真菌的表型和转录组学反应。这项研究也将使用相同的苔藓真菌系统，以监测差异基因表达与共生和saprotrophism三个非常不同的真菌物种之间的开关。

Plants are essential because they are the main source of carbon for terrestrial ecosystems. Similar to humans, and animals in general, plants harbor diverse microbial communities, including fungi. Mosses are a major component of boreal, arctic and alpine vegetation, which are most drastically impacted by environmental variation. They are known to host diverse fungal communities, living inside plant tissues (endophytic), such as leaves, without causing any visible symptoms. Endophytic fungi can actually help living plants in various ways, including the improvement of nutrient uptake and protection from pathogens. However, fungi are also known to be proficient decomposers of dead plant material. Switches between these functional states by fungi might be dynamic and potentially regulated by abiotic and biotic factors. Understanding the circumstances and mechanisms by which these functional transitions occur will greatly improve knowledge of plant-fungus interactions and their roles as symbiotic entities to maintain nutrient cycling and ecosystem functions. The researchers will participate in various outreach activities, including the annual Darwin Day exhibition event at the North Carolina Museum of Natural Sciences. This grant will greatly improve the co-PI's Ph.D. dissertation, and contribute to the development of an independent research program for a successful academic career. Previously, the researchers have examined endophytic fungal species and their function across a senescence gradient within moss plants using an innovative metatranscriptomic approach. Although active fungal species were found to be structured according to the senescence gradient of the moss, several fungi inhabit both the living (top) and decomposing (bottom) portions of the plant, providing multiple candidate fungal species to study trophic transitions between symbiotrophism and saprotrophism. The researchers will isolate some of these fungi in pure cultures and use them in an experiment designed to quantify the effects of focal fungal strains on living and dead moss tissues. Using co-culture experiments of these fungi with moss plants, this project will characterize the phenotypic, and transcriptomic, responses of mosses to their associated fungi. This research will use also the same moss-fungus system to monitor differential gene expression associated with a switch between symbiotrophism and saprotrophism by three very different fungal species.