DISSERTATION RESEARCH: Evolution of Generalism and Specialism in the RNA phage Phi6

论文研究：RNA 噬菌体 Phi6 的通用性和专业性的进化

• 批准号: 0408000
• 负责人: Paul Turner
• 金额: $ 1.2万
• 依托单位: Yale University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-09-01 至 2006-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0408000&HistoricalAwards=false
• 关键词: DISSERTATION; RESEARCH; Evolution; Generalism; Specialism

Biologists have long puzzled why most organisms specialize on few resources, rather than generalize by broadly exploiting the wide variety of resources that nature offers. Generalism seems a more tempting strategy, because it allows a larger niche space and the ability for organisms to thrive across a vast range of habitats. However, specialists appear to predominate in nature, perhaps due to their greater efficiency at exploiting a lesser number of resources. The costs of generalism (and their underlying mechanisms) have proven difficult to study. This research will use mutants of the RNA virus phi-6 that show an expanded ability to infect new host bacteria (i.e., generalist viruses), to examine hypothesized costs of generalism. The mutants will be evolved for hundreds of generations on a single novel host in order to test whether adaptation to the new host necessitates specialization (narrowing of the virus niche). Also, genomes of the evolved viruses will be sequenced to test two competing theories on how mechanisms for specialization evolve at the molecular level. This study is powerful because it uses a harmless virus of bacteria to study general questions regarding host shifts by viruses onto hosts. Virus phi-6 is an especially informative model for studying evolution of segmented RNA viruses, such as Hantavirus and Influenza which infect humans. Thus, results of the study should further the understanding of host-shifts involving pathogenic RNA viruses of higher organisms.

生物学家长期以来一直困扰着为什么大多数生物都专门从事很少的资源，而不是通过广泛利用大自然提供的各种资源来推广。 一般主义似乎是一种更诱人的策略，因为它允许更大的利基空间和生物体在各种栖息地繁衍生息的能力。 但是，专家似乎在本质上占主导地位，这可能是由于他们在利用较少数量的资源方面的效率提高。 事实证明，通用主义（及其基本机制）的成本很难研究。 这项研究将使用RNA病毒PHI-6的突变体，该突变体显示出扩展的感染新宿主细菌（即通才病毒）的能力，以检查普遍主义的假设成本。 突变体将在单个新颖的宿主上以数百代的形式进化，以测试适应新宿主是否需要专业化（病毒细分市场的狭窄）。 同样，进化病毒的基因组将被测序，以测试两种竞争理论，介绍了专业机制如何在分子水平发展。 这项研究之所以强大，是因为它使用细菌的无害病毒来研究有关病毒转移到宿主的宿主转移的一般问题。 病毒PHI-6是研究细分RNA病毒的演化，例如感染人类的​​hantavirus和流感型流感。 因此，研究的结果应进一步了解涉及较高生物体的致病性RNA病毒的宿主转移。