DISSERTATION RESEARCH: Do gut microbiota affect caterpillar herbivory and fitness?

论文研究：肠道微生物群会影响毛毛虫的食草和健康吗？

• 批准号: 1601787
• 负责人: Noah Fierer
• 金额: $ 1.61万
• 依托单位: University of Colorado at Boulder
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-06-01 至 2017-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1601787&HistoricalAwards=false
• 关键词: DISSERTATION; RESEARCH; Do; gut; microbiota

Recent studies have shown that some animals, including humans, are heavily dependent on trillions of bacteria and other microorganisms that inhabit their gut ("gut microbiota") to digest food and provide nutrients. Although this microbial partnership likely occurs in all animals, it remains unexplored in most. This project assesses the role of gut microbiota in caterpillars, some of which are globally destructive crop pests and thus of major economic interest. Understanding whether caterpillars are reliant on gut microbiota for feeding and growth could help in designing strategies for controlling them more effectively. Researchers will conduct an experiment using the tobacco hornworm caterpillar, a common pest of tomato and tobacco plants. Findings of this project will advance scientific understanding of how much animals and microbes have evolved to depend on each other. This study will also provide research experience for a community college student and will engage the public through an educational workshop and a museum event.Investigators will experimentally test the hypothesis that gut microbiota in the tobacco hornworm, Manduca sexta, affect host feeding behavior and fitness. The experiment will be based in southeastern Arizona, where a large population of wild M. sexta feed on the plant Datura wright-ii. To manipulate gut microbiota, researchers will use antibiotics to selectively remove microbes from D. wrightii without altering leaf chemical or nutritional properties. Feeding rates and development of the caterpillars, as well as fecundity of the resulting adult moths, will be measured and compared between control and antibiotic-treated groups. In addition, the size and composition of gut microbial communities will be characterized using DNA sequencing and fluorescence microscopy. Previous DNA sequencing data indicate that the number of microbes in the M. sexta gut is extremely low relative to other animals. Further, extreme chemical conditions within the caterpillar gut suggest that the gut microbes detected there are unlikely to be metabolically active. Therefore, the researchers anticipate that gut microbiota will not play a large role in host feeding or fitness. This result would challenge the current paradigm that animal growth and reproduction typically depend heavily upon microbial symbiosis.

最近的研究表明，包括人类在内的某些动物在很大程度上取决于数万亿种细菌和其他居住在其肠道（“肠道微生物群”）的微生物，以消化食物并提供营养。尽管这种微生物伙伴关系可能发生在所有动物中，但在大多数动物中仍未探索。该项目评估了肠道菌群在毛毛虫中的作用，其中一些是全球破坏性的作物害虫，因此具有主要的经济利益。了解毛毛虫是否依赖于肠道菌群来喂养和增长可以有助于设计更有效地控制它们的策略。研究人员将使用烟草虫毛毛虫（番茄和烟草植物的常见害虫）进行实验。该项目的发现将进一步了解彼此依赖的动物和微生物的科学理解。 这项研究还将为社区大学的学生提供研究经验，并将通过教育研讨会和博物馆活动与公众互动。投资者将在实验中检验以下假设：在烟草中肠道菌，Manduca Sexta中的肠道菌群影响宿主的喂养行为和健身。该实验将基于亚利桑那州东南部，那里的大量野生M. Sexta以Datura Wright-II为食。为了操纵肠道微生物群，研究人员将使用抗生素选择性地从D. wrightii中去除微生物，而不会改变叶子化学或营养特性。将在对照组和抗生素治疗的基团之间测量和比较毛毛虫的喂养率和开发以及所得成年飞蛾的繁殖力。另外，使用DNA测序和荧光显微镜表征肠道微生物群落的大小和组成。先前的DNA测序数据表明，相对于其他动物，M. sexta肠道中的微生物数量极低。此外，毛毛虫肠道内的极端化学条件表明，检测到的肠道微生物不太可能具有代谢活性。因此，研究人员预计肠道菌群在宿主喂养或健身方面不会发挥重要作用。该结果将挑战当前动物生长和繁殖通常在很大程度上取决于微生物共生的范式。