Wadsworth Center, New York State Department of Health, Slingerlands, NY, United States.
Infect Genet Evol. 2012 Apr;12(3):557-64. doi: 10.1016/j.meegid.2012.01.022. Epub 2012 Feb 1.
Mosquito-borne viruses are predominantly RNA viruses which exist within hosts as diverse mutant swarms. Defining the way in which stochastic forces within mosquito vectors shape these swarms is critical to advancing our understanding of the evolutionary and adaptive potential of these pathogens. There are multiple barriers within a mosquito which a viral swarm must traverse in order to ultimately be transmitted. Here, using artificial mutant swarms composed of neutral variants of West Nile virus (WNV), we tracked changes to swarm breadth over time and space in Culex pipiens mosquitoes. Our results demonstrate that all variants have the potential to survive intrahost bottlenecks, yet mean swarm breadth decreases during both midgut infection and transmission when starting populations contain higher levels of minority variants. In addition, WNV swarms are subject to temporal sweeps which act to significantly decrease intrahost diversity over time. Taken together, these data demonstrate the profound effects that stochastic forces can have in shaping arboviral mutant swarms.
蚊媒病毒主要是 RNA 病毒，在宿主中存在着多样化的突变群体。定义蚊媒中随机因素塑造这些突变群体的方式对于深入了解这些病原体的进化和适应潜力至关重要。在蚊子内部存在多个障碍，病毒突变群必须穿越这些障碍才能最终传播。在这里，我们使用由西尼罗河病毒（WNV）的中性变体组成的人工突变群，跟踪了在库蚊（Culex pipiens）中突变群广度随时间和空间的变化。我们的结果表明，所有变体都有潜力在宿主内瓶颈期存活下来，但当起始种群中含有更高水平的少数变体时，在中肠感染和传播过程中，平均突变群广度会降低。此外，WNV 突变群会受到时间扫荡的影响，随着时间的推移，突变群内的多样性会显著降低。总的来说，这些数据表明，随机因素在塑造虫媒病毒突变群方面具有深远的影响。
