UKRI/BBSRC-NSF/BIO:Hidden costs of infection: mechanisms by which parasites disrupt host-microbe symbioses and alter development

UKRI/BBSRC-NSF/BIO：感染的隐性成本：寄生虫破坏宿主-微生物共生并改变发育的机制

• 批准号: 2322173
• 负责人: Corlett Wood
• 金额: $ 121.55万
• 依托单位: University of Pennsylvania
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-08-15 至 2026-07-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2322173&HistoricalAwards=false
• 关键词: UKRI; BBSRC; NSF; BIO; Hidden

Plants are colonized by thousands of microscopic organisms, from bacteria to tiny animals like nematode worms. These microorganisms affect each other’s interactions with their shared host plant. Some make it easier for other microorganism to infect the host, while others prevent other microorganisms from successfully infecting. This research will investigate whether these interactions between microorganisms on the same host plant are due to resource competition or driven by the host’s immune response. The researchers will test these questions in a plant that is closely related to alfalfa. Like alfalfa, this plant relies on symbiotic bacteria that live within cells in the root for nitrogen - an important nutrient and a main ingredient in fertilizers. While these symbiotic bacteria provide an essential nutrient to the plant, they also make their host more vulnerable to infection by parasitic nematode worms. While this research focuses on a single species of plant, nearly all crop plants rely on symbiotic microbes for nutrients, so understanding how beneficial microbes influence the disease risk of their host is agriculturally relevant and ecologically significant. The broader impacts of this project include providing interdisciplinary training for the next generation of leaders in plant science; engaging undergraduate and high-school students from under-represented backgrounds in hands-on research; and developing a board game based on microbial colonization of plant roots.Microorganisms that share the same host affect each other’s colonization success. Cross-talk between co-colonizing microorganisms often manifests as a priority effect, in which an early encounter with one microorganism impacts the host’s response to later colonizers. This research will test two competing hypotheses to explain pervasive priority effects in host-associated communities: a defense-centered model, in which the host’s defense response to one invader has off-target effects on infection by another organism, and a resource-centered model, in which co-colonizers compete for host resources. This project will test these hypotheses in the model legume Medicago truncatula by experimentally infecting plants with a parasitic nematode that disrupts the symbiosis with nitrogen-fixing bacteria. Nematodes inhibit rhizobia colonization, while the rhizobia increase susceptibility to nematodes. The proposed research has five objectives: (1) determine the spatio-temporal scale of priority effects between rhizobia and nematodes and develop new tools to manipulate them; interrogate the relative roles of (2) defense and (3) carbon allocation in generating priority effects between these two microorganisms; (4) identify genes and pathways that underlie these priority effects; (5) train the next generation of plant researcher in essential concepts ecological theory, cell and molecular biology. This award is funded as part of a cooperative program with the UKRI/BBSRC in the UK.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.

植物被数千种微生物定植，从细菌到线虫蠕虫等小动物。这些微生物会影响彼此与共享宿主植物的互动。有些使其他微生物更容易感染宿主，而另一些微生物则阻止其他微生物成功感染。这项研究将调查同一宿主植物上微生物之间的这些相互作用是由于资源竞争引起的还是由宿主的免疫反应驱动的。研究人员将在与苜蓿密切相关的工厂中测试这些问题。像苜蓿一样，这种植物依赖于生存在氮根中的细胞内的共生细菌 - 一种重要的营养和肥料的主要诱导。尽管这些共生细菌为植物提供了必不可少的营养，但它们也使宿主更容易受到寄生虫蠕虫感染的影响。尽管这项研究的重点是一种植物，但几乎所有农作物植物都依靠共生微生物来营养，因此了解有益微生物如何影响其宿主的疾病风险是重要的，并且在生态上很重要。该项目的更广泛影响包括为植物科学领域的下一代领导者提供跨学科培训；从事动手研究中代表性不足背景的本科生和高中生的学生；并基于植物根部的微生物殖民化开发棋盘游戏。共享同一宿主的男生会影响彼此的殖民化成功。共同殖民化微生物之间的跨话通常表现为优先效应，其中一种微生物的早期相遇会影响宿主对后来殖民者的反应。这项研究将检验两个相互竞争的假设，以解释与宿主相关的社区的普遍优先效应：一种以防御为中心的模型，其中宿主对一个入侵者的防御反应对另一个有机体对感染的促进作用，而以资源为中心的模型，共同殖民者在该模型中竞争了宿主资源的竞争。该项目将通过实验感染植物的寄生线虫来测试豆科植物模型中的这些假设，该植物用氮固定细菌破坏了共生的植物。线虫抑制根瘤菌定殖，而根瘤菌会增加对线虫的敏感性。拟议的研究有五个目标：（1）确定根瘤菌和线虫之间优先效应的空间量表，并开发新工具来操纵它们；询问（2）防御和（3）碳分配在这两种微生物之间产生优先级影响中的相对作用； （4）确定这些优先效应的基因和途径； （5）在基本概念生态理论，细胞和分子生物学中培训下一代植物研究人员。该奖项是作为英国乌克里/BBSRC的教练计划的一部分资助的。该奖项反映了NSF的法定任务，并使用基金会的知识分子优点和更广泛的影响审查标准认为通过评估被认为是珍贵的支持。