Molecular and Fitness Barriers to Bunyavirus Reassortment

布尼亚病毒重组的分子和适应性障碍

• 批准号: 10719791
• 负责人: Mark D. Stenglein
• 金额: $ 41.9万
• 依托单位: COLORADO STATE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-08-10 至 2028-07-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10719791
• 关键词: Address; Animals; Antiviral Agents; Arthropod Vectors; Binding; Biology; Bunyavirales; Culicidae; Dangerousness; Data; Directed Molecular Evolution; Disadvantaged; Evolution; Face; Frequencies; Genetic Drift; Genotype; Glycoproteins; Goals; Habitats; Heart; Human; Immunity; Infection; Lead; Libraries; Life Cycle Stages; Molecular; Molecular Virology; Nature; Nucleoproteins; Orthobunyavirus; Parents; Pathway interactions; Phenotype; Plants; Population; Process; Proteins; RNA; RNA Viruses; Reassortant Viruses; Risk; Scientist; System; Techniques; Testing; Urbanization; Vaccines; Viral; Virus; Work; climate change; combat; cost; experimental study; fitness; improved; insight; pathogen; predictive modeling; prototype; risk prediction; tool; viral genomics

Project Summary / Abstract The bunyavirus order (Bunyavirales) includes significant human, animal, and plant pathogens. As with all segmented viruses, reassortment is a major driver of bunyavirus evolution. Reassortment can produce viruses with undesirable phenotypes, including the ability to infect new hosts. As the world becomes increasingly interconnected and disrupted by climate change, the opportunity for previously isolated bunyaviruses to meet and reassort is increasing. Compatibility between the proteins and RNAs of two viruses is a key determinant of whether they can produce viable reassortant progeny. And, because reassortment joins proteins and RNAs that have not adapted to work together, new reassortants face an uphill evolutionary battle when competing with their parents and other viruses in the population. This proposal will generate an improved mechanistic understanding of molecular barriers to reassortment and investigate evolutionary pathways that permit reassortants to emerge despite initial fitness disadvantages. We have devised a new system that uses libraries of competing minigenomes to quantify reassortment potential between large numbers of viruses simultaneously, and to define the molecular breakdown in cases when they can’t. Using these “minigenome melees” in concert with traditional techniques, we propose to answer targeted questions about the molecular compatibility between bunyaviruses. Our team combines expertise in viral genomics, molecular virology, mosquito infection, and virus evolution. In aim 1, we identify steps in the viral lifecycle that break down when bunyavirus replication proteins are mismatched and perform directed evolution experiments that force mismatched proteins to adapt to work together. This will explain a key constraint on bunyavirus reassortment and detail molecular interactions at the heart of the bunyavirus life cycle. In aim 2, we use our minigenome melee system to test the hypothesis that orthobunyavirus reassortment is relatively unconstrained by packaging. In aim 3, we test the hypothesis that bottlenecks associated with replication in mosquitoes enable less fit reassortant genotypes to gain a foothold in populations via the stochastic effect of genetic drift. At the conclusion of this project, we expect to have a substantially improved understanding of the molecular rules that determine whether two bunyaviruses can reassort, the fitness consequences of reassortment, and the evolutionary pathways by which reassortant viruses emerge. Our results could be used to parameterize models that predict bunyavirus emergence risk and will shed light on conserved interactions that could be targeted by antiviral drugs. Minigenome melees could in principle be used to study the biology and evolution of all kinds of RNA viruses, and we expect this work to establish this as a broadly useful platform.

项目概要/摘要 与所有病原体一样，布尼亚病毒目（布尼亚病毒目）包括重要的人类、动物和植物病原体。 分段病毒，重配是布尼亚病毒进化的主要驱动力重配可以产生病毒。 具有不良表型，包括感染新宿主的能力。 由于气候变化而相互关联和破坏，以前孤立的布尼亚病毒有机会相遇 并且重组正在增加。 两种病毒的蛋白质和RNA之间的相容性是它们能否产生病毒的关键决定因素 并且，因为重配连接了尚未适应工作的蛋白质和 RNA。 新的重组体在与父母和其他物种竞争时，面临着一场艰苦的进化之战。 该提案将提高对分子机制的理解。 重配的障碍并研究允许重配出现的进化途径 最初的健身劣势。 我们设计了一种新系统，使用竞争性小基因组库来量化重配 同时分析大量病毒之间的潜力，并定义病例中的分子分解 当他们不能时，我们建议将这些“小基因组混战”与传统技术结合起来。 我们的团队结合了有关布尼亚病毒之间分子相容性的针对性问题。 病毒基因组学、分子病毒学、蚊子感染和病毒进化方面的专业知识。 在目标 1 中，我们确定了病毒生命周期中的步骤，当布尼亚病毒复制蛋白被破坏时，这些步骤就会被破坏。 不匹配并进行定向进化实验，迫使不匹配的蛋白质适应工作 这将解释布尼亚病毒重组的关键限制并详细说明分子相互作用。 布尼亚病毒生命周期的核心 在目标 2 中，我们使用我们的小基因组混战系统来检验以下假设： 正布尼亚病毒重配相对不受包装的限制 在目标 3 中，我们检验了以下假设： 与蚊子复制相关的瓶颈使得不太适合的重配基因型能够在蚊子中立足。 通过遗传漂变的随机效应。 在这个项目结束时，我们希望对分子的理解有一个实质性的提高。 确定两种布尼亚病毒是否可以重配的规则、重配的适应性后果以及 我们的结果可用于参数化重配病毒的进化途径。 预测布尼亚病毒出现风险并将揭示可能的保守相互作用的模型 原则上，小基因组混战可用于研究抗病毒药物的生物学和进化。 各种 RNA 病毒，我们希望这项工作能够将其建立为一个广泛有用的平台。