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.

植物上栖息着数以千计的微生物，从细菌到线虫等微小动物，这些微生物会影响彼此与共享宿主植物的相互作用，而另一些则使其他微生物更容易感染宿主。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还是由宿主的免疫反应驱动，研究人员将在密切相关的植物中测试这些问题。与苜蓿一样，这种植物依赖于根部细胞内的共生细菌来获取氮，氮是一种重要的营养物质，也是肥料的主要成分。虽然这些共生细菌为植物提供了必需的营养，但它们也使它们的宿主变得更加重要。虽然这项研究主要针对单一物种的植物，但几乎所有农作物都依赖共生微生物获取营养，因此了解有益微生物如何影响宿主的疾病风险具有农业意义和意义。该项目具有更广泛的生态影响，包括为下一代植物科学领导者提供跨学科培训；让来自弱势群体的本科生和高中生参与实践研究；以及开发基于微生物定植的棋盘游戏；共享同一宿主的微生物会影响彼此的定殖成功。共定殖微生物之间的串扰通常表现为优先效应，其中与一种微生物的早期接触会影响宿主的反应。这项研究将测试两个相互竞争的假设，以解释宿主相关群落中普遍存在的优先效应：以防御为中心的模型，其中宿主对一种入侵者的防御反应对另一种生物体的感染具有脱靶效应。以资源为中心的模型，其中共同定殖者竞争宿主资源，该项目将通过实验用破坏植物的寄生线虫感染植物来在豆科植物蒺藜苜蓿中测试这些假设。与固氮细菌的共生抑制根瘤菌定植，而根瘤菌增加对线虫的敏感性。本研究有五个目标：（1）确定根瘤菌和线虫之间优先效应的时空尺度，并开发操纵它们的新工具。 ；询问（2）防御和（3）碳在这两种微生物之间产生优先效应的相对作用；（4）确定这些微生物的基因分配和途径；优先效应；（5）培训下一代植物研究人员的基本概念生态理论、细胞和分子生物学。该奖项是与英国 UKRI/BBSRC 合作项目的一部分。该奖项反映了 NSF 的法定使命和使命。通过使用基金会的智力价值和更广泛的影响审查标准进行评估，该项目被认为值得支持。