DISSERTATION RESEARCH: Diversity and Functions of Interactions between the Liverwort Marchantia polymorpha and its Fungal Endophytes

论文研究：地钱及其内生真菌相互作用的多样性和功能

• 批准号: 1501826
• 负责人: Arthur Shaw
• 金额: $ 2.07万
• 依托单位: Duke University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-06-01 至 2017-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1501826&HistoricalAwards=false
• 关键词: DISSERTATION; RESEARCH; Diversity; Functions; Interactions

Plants are defining components of natural ecosystems where they provide habitats for other organisms and influence the composition of soils and the atmosphere. Fungi, though less conspicuous, significantly affect the success of living plants in addition to breaking down dead matter. Fungi that live inside healthy plants, called fungal endophytes (hereafter simply endophytes), can benefit plants in many ways, including promoting growth, enhancing disease resistance, and increasing resilience to extreme conditions such as drought. Therefore, understanding how endophytes interact with their host plants is critical for managing wild ecosystems as well as increasing productivity in forestry and agriculture as plants respond to extreme weather in a changing climate. Endophytes have been found in nearly all plants sampled to date but there are few direct studies of the mechanisms behind their functions. This project investigates the diversity and functions of endophytes in a liverwort. This project will sample the diversity of endophytes in a model liverwort, Marchantia polymorpha, and investigate what factors influence this diversity. M. polymorpha grows well in the laboratory, so this project will directly test the effects of individual endophytes. Using genetic methods, the researcher will identify possible mechanisms behind the observed interactions. In addition, the study system developed in this project will provide many future opportunities for plant-endophyte interaction research.The researchers will collect Marchantia polymorpha plants from ten populations across the USA and characterize the diversity of the liverworts and their endophytes. Liverwort genotypes will be assessed using Restriction-site Associated DNA sequencing (RAD-seq) to sample sites throughout the genome. Internal fungal diversity will be sampled by surface sterilizing whole M. polymorpha plants, extracting total DNA, then amplifying and sequencing a fungal barcoding gene region. The researchers will test for correlations between fungal community diversity and composition, host genotypes, and population locations. These data will provide an ecological context for previous experiments testing the effects of cultured endophytes on M. polymorpha in laboratory growth assays. To investigate the mechanisms behind the liverwort-endophyte interactions observed in the laboratory, the researchers will sequence the transcriptomes of the plant and selected fungi when grown alone and together. Four fungi will be used: a growth-enhancing fungus, a detrimental fungus, and close relatives of each which show a neutral interaction. Comparing the levels of gene expression between the treatments and controls will allow the researcher to form hypotheses about which cellular systems may be important in controlling the observed interactions.

植物正在定义天然生态系统的组成部分，它们为其他生物提供栖息地，并影响土壤和大气的组成。真菌虽然不太明显，但除了打破死物质外，还显着影响活植物的成功。生活在健康植物中的真菌，称为真菌内生菌（以下简称内生菌），可以在许多方面使植物受益，包括促进生长，增强疾病耐药性以及对干旱等极端状况的韧性。因此，了解内生的植物如何与宿主植物相互作用对于管理野生生态系统以及在不断变化的气候下对极端天气的反应时，林业和农业的生产率提高至关重要。迄今为止，几乎所有采样的植物都发现了内生菌，但是对其功能背后的机制几乎没有直接研究。该项目研究了肝脏中内生菌的多样性和功能。该项目将在Liverwort，Marchantia Polymorpha中采样内生菌的多样性，并研究哪些因素会影响这种多样性。 M. Polymorpha在实验室中生长良好，因此该项目将直接测试单个内生菌的影响。使用遗传方法，研究人员将确定观察到的相互作用背后的可能机制。此外，该项目中开发的研究系统将为植物 - 植物相互作用研究提供许多未来的机会。研究人员将从美国十个人群中收集Marchantia Polymorpha植物，并表征Liverworts及其内生的多样性。将使用限制位置相关的DNA测序（RAD-SEQ）评估肝脏基因型，以对整个基因组的样品位点进行评估。内部真菌多样性将通过对整个多形植物进行灭菌，提取总DNA，然后扩增和测序真菌条形码基因区域的表面进行采样。研究人员将测试真菌社区多样性与组成，宿主基因型和人口位置之间的相关性。 这些数据将为先前的实验提供一个生态环境，以测试培养的内生菌对实验室生长测定中多晶型菌的影响。为了研究在实验室观察到的Liverwort-endophyte相互作用背后的机制，研究人员将在单独和一起生长时对植物的转录组和选择的真菌进行测序。将使用四种真菌：一种增强生长的真菌，有害的真菌和每个显示中性相互作用的近亲。比较治疗和对照组之间的基因表达水平将使研究人员能够形成假设，即哪种细胞系统在控制观察到的相互作用中可能很重要。