The Molecular Basis of Host Adaptation and Origin of New Mutualisms

宿主适应的分子基础和新互惠关系的起源

• 批准号: 1258099
• 负责人: Cheryl Whistler
• 金额: $ 71.66万
• 依托单位: University of New Hampshire
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-09-15 至 2017-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1258099&HistoricalAwards=false
• 关键词: Molecular; Basis; Host; Adaptation; Origin

Beneficial bacteria are the foundation of health in both plants and animals. Although disease-causing bacteria have received intensive scientific attention, the processes that drive the evolution of beneficial bacterial symbioses are still poorly understood. This project will apply the techniques and conceptual perspectives of molecular genetics, microbiology and evolutionary biology to document the genetic processes involved in evolution of beneficial symbiosis. The project will make use of an unusually tractable experimental model involving marine animals and their symbiotic bacteria: the symbiosis between bobtail squid and a light-producing bacterium, Vibrio fischeri. Some strains of Vibrio fischeri form life-long symbioses with squid and fish, whereas other strains are free-living in the marine environment. Exploiting the natural variation in this bacterium, the investigators will compare six V. fischeri strains with diverse environmental histories and differing initial capacities for colonization of squid hosts to identify bacterial mutations correlated with successful animal colonization, and with evolution of beneficial symbiotic interactions. This is among the first experimental evolution models, and the only natural model, to explore the mechanistic basis of beneficial host-adaptation in symbiotic microbes. The project includes interdisciplinary training for several graduate and undergraduate students, and capitalizes upon an engaging model system to promote an understanding of evolution and of symbiosis among students at all educational levels. The project will also develop educational resources for middle and high school teachers, including hands-on experiments using beneficial microbes in the classroom.

有益细菌是植物和动物健康的基础。虽然致病细菌已经得到了广泛的科学关注，但推动有益细菌共生体进化的过程仍然知之甚少。本项目将应用分子遗传学、微生物学和进化生物学的技术和概念观点来记录有益共生进化中涉及的遗传过程。该项目将利用一种涉及海洋动物及其共生细菌的非常容易处理的实验模型：短尾鱿鱼与一种发光细菌-费氏弧菌-之间的共生。一些费氏弧菌菌株与鱿鱼和鱼类形成终身共生，而其他菌株则在海洋环境中自由生活。利用这种细菌的自然变异，研究人员将比较六种具有不同环境历史和不同鱿鱼宿主定植初始能力的V. fischeri菌株，以确定与成功的动物定植相关的细菌突变，以及有益的共生相互作用的进化。这是第一个实验进化模型之一，也是唯一的自然模型，用于探索共生微生物中有益宿主适应的机制基础。该项目包括对几名研究生和本科生进行跨学科培训，并利用一个引人入胜的模型系统，促进各级教育学生对进化和共生的理解。该项目还将为初中和高中教师开发教育资源，包括在课堂上使用有益微生物的动手实验。