Department of Biomedical Engineering, Columbia University, New York, NY 10027, USA; Laboratory of Virology and Infectious Disease, The Rockefeller University, New York, NY 10065, USA.
Laboratory of Virology and Infectious Disease, The Rockefeller University, New York, NY 10065, USA; Department of Physiology, Biophysics, and Systems Biology, Weill Cornell Medicine, New York, NY 10065, USA.
Cell Syst. 2021 Mar 17;12(3):210-219.e3. doi: 10.1016/j.cels.2020.12.005. Epub 2021 Jan 29.
While decades of research have elucidated many steps of the alphavirus lifecycle, the earliest replication dynamics have remained unclear. This missing time window has obscured early replicase strand-synthesis behavior and prevented elucidation of how the first events of infection might influence subsequent viral competition. Using quantitative live-cell and single-molecule imaging, we observed the initial replicase activity and its strand preferences in situ and measured the trajectory of replication over time. Under this quantitative framework, we investigated viral competition, where one alphavirus is able to exclude superinfection by a second homologous virus. We show that this appears as an indirect phenotypic consequence of a bidirectional competition between the two species, coupled with the rapid onset of viral replication and a limited total cellular carrying capacity. Together, these results emphasize the utility of analyzing viral kinetics within single cells.
虽然几十年来的研究已经阐明了甲病毒生命周期的许多步骤，但最早的复制动态仍然不清楚。这个缺失的时间窗口掩盖了早期复制酶链合成行为，并阻止了阐明感染的最初事件如何影响随后的病毒竞争。使用定量活细胞和单分子成像，我们在原位观察了初始复制酶的活性及其链偏好，并测量了随时间推移的复制轨迹。在这个定量框架下，我们研究了病毒竞争，其中一种甲病毒能够排除第二种同源病毒的超感染。我们表明，这似乎是两种病毒之间的双向竞争的间接表型后果，加上病毒复制的快速开始和有限的总细胞承载能力。总之，这些结果强调了在单细胞内分析病毒动力学的效用。
