On the nature and regulation of the plant-fungal biotrophic interface

在植物感染期间，许多致病真菌，包括破坏性的水稻和小麦稻瘟病菌Magnaporthe oryzae，可以长时间与活宿主细胞密切接触生长。这种寄生（生物营养）生长阶段包括寄主植物膜在真菌入侵菌丝周围的增生，形成界面区，在该界面区部署效应器并获得营养。尽管生物营养界面和与宿主感染相关的室室具有内在性质，但界面膜维持和构建的生物学基础在很大程度上是未知的。这严重破坏了了解寄主-病原体相互作用的努力，并可能模糊寄主抗性的新来源，以及确定限制广泛植物疾病和改善作物健康的新目标。该项目旨在通过表征在寄主植物细胞生长过程中不能适当维持生物营养界面功能或膜完整性的米曲菌突变株来解决这些知识空白。这有望揭示控制水稻感染的新的细胞、生化和遗传机制。结果可能揭示植物宿主-微生物相互作用的基本概念，可以利用这些概念来了解如何促进有益的植物-真菌相互作用，同时减少对作物健康有害的相互作用。我们还期望这项工作将为学生的学习提供一个充满活力的环境，激励代表性不足的学生考虑从事STEM职业，成为下一代科学家。根据我们最近的发现，我们的中心假设是，尽管包括植物和真菌膜，生物营养界面是真菌结构，其特性和动力学由入侵真菌的代谢需求决定。在这里，我们试图通过利用新的突变菌株来验证我们的假设，以提供有关生物营养界面调节，动力学和功能的重要新信息。通过关注维持生物营养界面完整性所需的真菌过程，并通过检查生物营养界面功能的一些重要方面，所述的目标将使用正向和反向遗传学，多组学方法和活细胞成像来了解真菌代谢过程如何主导活宿主细胞中的植物-真菌相互作用。这可能会导致针对真菌生物营养生长至关重要但不是宿主细胞正常功能所必需的分子途径的新型作物保护策略的发展，并可能为细胞生长的基本原理以及宿主-微生物界面的性质和调节提供新的思路。教育目标将激励本科生在研究中脱颖而出，将允许研究生发展为导师和教师，并将为所有学生提供在STEM职业生涯中脱颖而出的工具。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。

During plant infection, many pathogenic fungi, including the devastating rice and wheat blast fungus Magnaporthe oryzae, can grow in intimate contact with living host cells for extended periods of time. This parasitic (biotrophic) growth stage involves the accretion of host plant membranes around fungal invasive hyphae, forming interfacial zones across which effectors are deployed and nutrients are acquired. Despite the intrinsic nature of the biotrophic interface and associated compartments to host infection, the biological underpinnings of interfacial membrane maintenance and construction are largely unknown. This severely undermines efforts to understand the host-pathogen interaction and likely obscures novel sources of host resistance and the identification of new targets for limiting a broad range of plant diseases as well as improving crop health. This project seeks to address these knowledge gaps by characterizing mutant strains of M. oryzae that fail to properly maintain biotrophic interfacial function or membrane integrity during growth in host plant cells. This is expected to uncover novel cellular, biochemical, and genetic mechanisms governing rice infection. Results may shed light on fundamental concepts of plant host-microbe interactions that could be leveraged to understand how beneficial plant-fungal interactions might be promoted while those detrimental to crop health are diminished. We also expect that this work will provide an invigorating environment for student learning that will inspire underrepresented students to consider a STEM career and become the next generation of scientists.Based on our recent discoveries, our central hypothesis is that, despite comprising both plant and fungal membranes, biotrophic interfaces are fungal constructs with properties and dynamics dictated by the metabolic demands of the invading fungus. Here, we seek to test our hypothesis by leveraging novel mutant strains to provide important new information on biotrophic interfacial regulation, dynamics, and function. By focusing on fungal processes required for maintaining biotrophic interfacial integrity, and by examining some important aspects of the function of the biotrophic interface, the stated objectives will use forward and reverse genetics, multiomic approaches, and live-cell imaging to understand how fungal metabolic processes dominate the plant-fungal interaction in living host cells. This could lead to the development of novel crop protection strategies targeting molecular pathways that are critical for the biotrophic growth of the fungus but are not required for the normal function of the host cell, and could shed new light on both the basic principles of cell growth, and on the nature and regulation of host-microbe interfaces. The educational objective will inspire undergraduates to excel in research, will allow graduate students to develop as mentors and teachers, and will provide all students with the tools to excel in STEM careers.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.