Collaborative Research: Development, Structure, and Function of the Bacterial Symbiont Colonization Site in Steinernematid Nematodes

合作研究：斯坦氏线虫细菌共生体定植位点的发育、结构和功能

• 批准号: 0416783
• 负责人: Heidi Goodrich-Blair
• 金额: $ 20.16万
• 依托单位: University of Wisconsin-Madison
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-07-15 至 2007-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0416783&HistoricalAwards=false
• 关键词: Collaborative; Research; Development; Structure; Function

Most children are taught that germs (microbes) will make them sick, and indeed, some can. However, the more common natural relationship between animals and microbes is mutually beneficial (mutualistic) since microbes are absolutely necessary for normal animal development, nutrition, and immunity. In these associations microbes typically colonize discrete locations on or within the animal. Little is as yet understood regarding the distinct physical nature of such colonization sites, or how beneficial animal-microbe associations are formed and maintained. It is known that these processes rely on animal-microbe communication that can involve chemical signals exchanged from a distance, as well as signaling through direct physical contact. Still lacking is a fundamental understanding of the identities of signals, how and where they are produced, how they are recognized, and the effects they mediate in each partner. To begin to address these questions, the proposed research focuses on an emerging model of animal-microbe mutualism between a small, soil-dwelling nematode (roundworm) and the beneficial bacterium (symbiont) with which it associates. The bacterial symbiont lives in a specific vesicle (receptacle) within the intestine of the nematode, and is the only microbe capable of residing at this location and establishing a relationship with the nematode; in other words, it is the only microbe that can correctly communicate with the nematode to achieve a mutually beneficial relationship. In this study the morphological and developmental features of the nematode intestinal vesicle will be analyzed to better understand the colonization process. The proposed research will also explore new hypotheses regarding the chemical signals and the physical interactions that occur between the nematode and the symbiont and how these interactions might affect the physiology of each organism. Furthermore, the proposed research will address questions of how such intimate animal-microbe associations evolve.The specific goal of this proposal is to characterize, using microscopy, biochemistry, and microbial genetics, the structure and development of the interaction between the nematode and the symbiont and how each partner contributes to this relationship. The model system being studied is easily studied in the laboratory. The three labs involved in this collaborative research are each contributing distinct expertise required for the proposed studies. Together these labs will:1) Analyze, using microscopy and biochemistry, the physical aspects of the nematode intestinal region that interacts with the microbial symbiont;2) Compare the intestinal structures of different nematodes to understand how the ability to specifically interact with the symbiont evolved;3) Study how the intestinal region that interacts with the symbiont develops, and how the symbiont affects this development; and4) Characterize, using biochemistry and genetics, the chemical signals exchanged between the nematode and the symbiont.This model system is well suited for education because of its broad relevance to agricultural, medical, and basic research and multiple disciplinary perspectives. An underrepresented minority undergraduate has contributed to preliminary research, and each lab will continue to train and educate students from diverse backgrounds. A workshop will be held that includes data and techniques developed through this research. Finally, this study will enhance a K-12 teaching tool developed as part of the NSF-funded K through Infinity program at UW-Madison.

大多数孩子被教导说细菌（微生物）会使他们生病，实际上有些可以。但是，动物与微生物之间更常见的自然关系是互惠互利的（相互主义），因为微生物对于正常动物发育，营养和免疫力绝对必要。在这些关联中，微生物通常在动物内或内部定居离散位置。关于这种定殖位点的独特物理性质或如何形成和维持有益的动物 - 微生物关联，几乎没有理解。众所周知，这些过程依赖于动物 - 微生物通信，该动物可以涉及从距离交换的化学信号，以及通过直接物理接触的信号传导。仍然缺乏对信号的身份，如何产生和在何处，被认可的方式以及它们在每个合作伙伴中的效果的基本理解。为了开始解决这些问题，拟议的研究重点是在小型土壤居住的线虫（round虫）和与之相关的有益细菌（Symbiont）之间的动物菌互动模型。细菌共生体生活在线虫肠内的特定囊泡（容器）中，并且是唯一能够居住在该位置并与线虫建立关系的微生物。换句话说，它是唯一可以与线虫正确通信以实现互惠关系的微生物。在这项研究中，将分析线虫肠囊泡的形态和发育特征，以更好地了解定殖过程。拟议的研究还将探讨有关化学信号以及在线虫与共生体之间发生的物理相互作用的新假设，以及这些相互作用如何影响每个生物体的生理学。此外，拟议的研究将解决有关这种亲密动物微叶片关联如何发展的问题。该提案的具体目标是使用显微镜，生物化学和微生物遗传学表征，即线虫与Symbiont之间的相互作用的结构和发展，以及每个伙伴之间的相互作用的结构和发展。在实验室中很容易研究正在研究的模型系统。这项合作研究涉及的三个实验室每个人都为拟议的研究提供了独特的专业知识。这些实验室将共同：1）使用显微镜和生物化学分析与微生物共生体相互作用的线虫肠道区域的物理方面； 2）比较不同线虫的肠结构，以了解如何与Symbiont互动的能力相互作用； 3）如何与Symbion的相互作用; 3）相互作用; 3）相互作用; 3）相互作用；和4）表征，使用生物化学和遗传学，在线虫和共生体之间交换的化学信号。该模型系统非常适合教育，因为它与农业，医学和基础研究以及多个纪律观点的广泛相关。代表性不足的少数族裔本科生为初步研究做出了贡献，每个实验室将继续培训和教育来自不同背景的学生。将举行一个研讨会，其中包括通过这项研究开发的数据和技术。最后，这项研究将增强通过UW-Madison的Infinity计划作为NSF资助K的一部分开发的K-12教学工具。