Quasispecies dynamics in arbovirus persistence emergence and fitness

虫媒病毒持久性出现和适应性的准种动态

• 批准号: 10578761
• 负责人: Gregory David Ebel
• 金额: $ 45.57万
• 依托单位: COLORADO STATE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-05-15 至 2027-01-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10578761
• 关键词: 2019-nCoV; Address; Affect; Alphavirus; Antibodies; Arboviruses; Bar Codes; Biology; Biometry; Birds; Cells; Chikungunya virus; Competence; Complement; Culex (Genus); Culicidae; Data; Disease; Disease Outbreaks; Ecology; Environment; Evolution; Face; Flaviviridae; Flavivirus; Flavivirus Infections; Flow Cytometry; Funding; Future; Genetic Variation; Genome; Genotype; Geography; Goals; Health; Human; Humanities; Incubated; Individual; Infection; Insecticide Resistance; Knowledge; Literature; Maintenance; Medicine; Methodology; Midgut; Molecular; Molecular Biology; Natural Selections; Nature; Nucleotides; Outcome; Phase; Population; Population Biology; Population Genetics; Population Heterogeneity; Public Health; RNA Sequences; RNA Viruses; Research; Role; Salivary Glands; Shapes; System; Temperature; Testing; Time; Tissues; Togaviridae; Urbanization; Vaccines; Variant; Vertebrates; Viremia; Virion; Virus; West Nile virus; Work; Zika Virus; computerized tools; environmental change; fitness; global temperature; innovation; land use; multidisciplinary; mutant; novel; prevent; theories; tool; transmission process; vector; vector competence; vector mosquito; viral fitness; virology

Arthropod-borne viruses (arboviruses) adapt to local conditions, maximizing their potential to perpetuate and emerge as health threats. The adaptive potential of arboviruses is driven by error-prone replication, which creates a genetically diverse pool of competing virus genotypes within each host. This proposal examines some of the ways that temperature may impact arbovirus evolutionary biology. Our previous research has allowed us to make clear predictions about the outcome of each proposed aim, and generated molecular and computational tools, and methodological approaches that we propose to combine in this project. Global temperatures are changing at an unprecedented rate, and RNA viruses such as WNV continue to emerge at a frightening pace. Our preliminary studies have shown quite clearly that temperature is a key factor that dictates how natural selection affects arboviruses within mosquitoes. Therefore, Aim 1 will address how temperature, both constant and fluctuating, with varying means and amplitudes, alters natural selection on WNV within mosquitoes and the strength of bottlenecks. Our predictions (in general) are that fluctuating temperatures will increase the strength of purifying selection, that diversity will be maximized at optimal constant temperatures, and that bottlenecks will become wider as temperature increases. Our results have demonstrated that flavivirus infections are most frequently initiated by aggregates of virus particles. Aim 2 will address the extent that this occurs in a host- and temperature-dependent manner, bringing our previous work into a more ecologically relevant, realistic context. In the second phase of Aim 2, we will ask whether these genome aggregates can help to facilitate the maintenance of genetic diversity in the WNV population. Birds that generate high WNV viremia and are highly infectious to mosquitoes have significantly more unique WNV genomes per cell than those that have lower viremias. Aim 3 will assess whether something similar may occur in mosquitoes. We will use barcoded WNV to infect mosquitoes with a range of vector competence and assess the number of unique WNV genomes per cell. As above, we also will assess the degree to which this phenomenon may allow for the maintenance of low fitness viral genotypes while preventing those of high fitness from gaining dominance. This work will provide comprehensive data on the ways that changing environmental conditions may alter the fundamental population biology of arboviruses. Our work is also significant because it will provide mechanistic data on how viruses may maintain genetic diversity in the face of both selective and stochastic reductions in genetic diversity. The proposed studies are technically and conceptually innovative because of the ways that we can combine realistic transmission systems in the lab with barcoded viruses, single cell approaches, and other new molecular tools.

节肢动物传播的病毒（虫媒病毒）适应当地条件，最大限度地发挥其潜力， 成为健康威胁。虫媒病毒的适应潜力是由易错复制驱动的， 在每一个宿主体内产生了一个基因多样的竞争病毒基因型库。该提案审查了 温度可能影响虫媒病毒进化生物学的一些方式。我们之前的研究 使我们能够对每个目标的结果做出明确的预测，并产生分子和 计算工具和方法论的方法，我们建议在这个项目中联合收割机。 全球气温正以前所未有的速度变化，RNA病毒如西尼罗河病毒继续在全球范围内传播。 以惊人的速度出现我们的初步研究已经清楚地表明，温度是一个关键因素， 自然选择如何影响蚊子体内的虫媒病毒。因此，目标1将解决如何 温度，无论是恒定的还是波动的，以不同的手段和幅度，改变了自然选择， 西尼罗河病毒是蚊子体内的力量和瓶颈。我们的预测（一般来说）是波动的， 温度将增加净化选择的强度，在最佳条件下， 在恒定的温度下，瓶颈会随着温度的升高而变宽。 我们的研究结果表明，黄病毒感染最常见的是由病毒聚集体引起的， 粒子目标2将解决这种情况以宿主和温度依赖的方式发生的程度， 我们以前的工作融入到一个更加生态相关的现实环境中。在目标2的第二阶段，我们将问 这些基因组聚集体是否有助于促进西尼罗河病毒遗传多样性的维持 人口 产生高WNV病毒血症并对蚊子具有高度感染性的鸟类具有明显更独特的 每个细胞的WNV基因组比那些具有较低的病毒数。目标3将评估类似的东西是否可能 发生在蚊子身上。我们将使用条形码化的WNV感染具有一系列载体能力的蚊子， 评估每个细胞独特的WNV基因组的数量。如上所述，我们也将评估这一点的程度， 这一现象可能允许维持低适应性病毒基因型，同时防止高适应性病毒基因型。 获得优势的适应性。 这项工作将提供全面的数据，说明不断变化的环境条件可能会改变 虫媒病毒的基本种群生物学。我们的工作也很重要，因为它将提供机械的 关于病毒如何在面临选择性和随机减少的情况下保持遗传多样性的数据， 遗传多样性拟议的研究在技术和概念上都是创新的，因为 我们可以将实验室中的联合收割机实际传输系统与条形码病毒、单细胞方法相结合， 其他新的分子工具。