EVOLUTION IN MICROBES--POPULATION STRUCTURE AND GENETICS

微生物的进化——种群结构和遗传学

• 批准号: 2175958
• 负责人: JULIAN P. ADAMS
• 金额: $ 20.03万
• 依托单位: UNIVERSITY OF MICHIGAN AT ANN ARBOR
• 依托单位国家: 美国
• 财政年份: 1982
• 资助国家: 美国
• 起止时间: 1982-08-01 至 1996-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2175958
• 关键词: Escherichia coli; Saccharomyces cerevisiae; bacterial genetics; biochemical evolution; fungal genetics; gene interaction; gene mutation; genetic mapping; genetic polymorphism; genetic strain; mass spectrometry; microorganism culture; microorganism population study; molecular cloning; nuclear magnetic resonance spectroscopy; nucleic acid sequence; population genetics

The long-term objectives of this proposal are to understand the process of evolution in asexual micro-organism populations, and their genetic structure. The wealth of genetic and biochemical information available for Escherichia coli and Saccharomyces cerevisiae permits a level of analysis not possible with many other organisms. Recent work has revealed that asexual micro-organism populations exhibit a wide-range of "interesting" and complex evolutionary responses that are analogous to evolutionary phenomena seen in diploid, sexually reproducing higher eukaryotes. In particular, populations initiated with a single clone, and grown in a simple unstructured environment, become polymorphic within a surprisingly short period of time. We will continue, and complete the analysis of a three component stable polymorphism that has been observed to develop in a population of E coli initiated with a single clone and grown in glucose-limited continuous culture for 765 generations. We will, i) determine the mechanisms responsible for interactions between the components, which serve to maintain the polymorphism, ii) determine the genetic bases for the interactions, by mapping, cloning and sequencing the loci responsible, iii) determine the necessary and sufficient conditions for the establishment of the polymorphism, and iv) determine the dynamics and fate of the polymorphism during continued evolution of the populations. In addition, we will analyze a unique "bank" of samples (taken every about 10 generations) from more that 40 evolving populations of E coli and S cerevisiae, to determine the genetic and biochemical bases for mechanisms which may result in the establishment of other stable polymorphisms. Here, our goal will be to determine the range of evolutionary changes which can generate and maintain genetic variation in simple, unstructured environments. As well as being important to population genetics and evolution, these studies will provide important information on the evolution and aging of proliferating cell populations. The complete understanding of cell proliferation and the genetic changes that cells undergo is critically important to many aspects of medicine, not the least of which are cancer therapy and aging.

本提案的长期目标是了解 无性微生物种群的进化及其遗传 结构 丰富的遗传和生化信息 对于大肠杆菌和酿酒酵母， 分析不可能与许多其他生物。 最近的研究表明，无性微生物种群表现出 一系列“有趣的”和复杂的进化反应， 类似于二倍体的进化现象，有性繁殖 高等真核生物 特别是， 克隆，并在简单的非结构化环境中生长，变得多态 在一个令人惊讶的短时间内 我们会继续， 完成对三组分稳定多态性的分析， 已经观察到在由单个 克隆并在葡萄糖限制的连续培养中生长765代。 我们将，i）确定负责相互作用的机制， 用于维持多态性的组分，ii）确定 通过作图、克隆和测序， （三）确定必要和充分的 建立多态性的条件，和iv）确定 多态性在持续进化过程中的动态和命运 人口。 此外，我们将分析一个独特的样本“银行”（采取每约 10代），从40多个进化的大肠杆菌和S 酿酒酵母，以确定机制的遗传和生化基础 这可能导致其他稳定多态性的建立。 在这里，我们的目标将是确定进化变化的范围 它可以在简单的、非结构化的环境中产生和维持遗传变异 环境. 除了对种群遗传学和进化很重要外， 这些研究将提供关于人类进化和衰老的重要信息， 增殖细胞群。 对细胞的完整理解 细胞的增殖和遗传变化是至关重要的 对医学的许多方面都很重要，尤其是癌症 治疗和衰老