Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), College of Chemistry and Molecular Sciences, State Key Laboratory of Virology, The Institute for Advanced Studies, and Wuhan Institute of Biotechnology, Wuhan University , Wuhan 430072, P.R. China.
ACS Nano. 2017 May 23;11(5):4395-4406. doi: 10.1021/acsnano.6b07853. Epub 2017 Apr 3.
Entry is the first critical step for the infection of influenza A virus and of great significance for the research and development of antiflu drugs. Influenza A virus depends on exploitation of cellular endocytosis to enter its host cells, and its entry behaviors in distinct routes still need further investigation. With the aid of a single-virus tracking technique and quantum dots, we have realized real-time and multicolor visualization of the endocytic process of individual viruses and comprehensive dissection of two distinct dynamin-dependent endocytic pathways of influenza A virus, either dependent on clathrin or not. Based on the sequential progression of protein recruitment and viral motility, we have revealed the asynchronization in the recruitments of clathrin and dynamin during clathrin-dependent entry of the virus, with a large population of events for short-lived recruitments of these two proteins being abortive. In addition, the differentiated durations of dynamin recruitment and responses to inhibitors in these two routes have evidenced somewhat different roles of dynamin. Besides promoting membrane fission in both entry routes, dynamin also participates in the maturation of a clathrin-coated pit in the clathrin-dependent route. Collectively, the current study displays a dynamic and precise image of the entry process of influenza A virus and elucidates the mechanisms of distinct entry routes. This quantum dot-based single-virus tracking technique is proven to be well-suited for investigating the choreographed interactions between virus and cellular proteins.
进入是甲型流感病毒感染的第一步，对抗流感药物的研究和开发具有重要意义。甲型流感病毒依赖于细胞内吞作用进入宿主细胞，其不同途径的进入行为仍需要进一步研究。借助单病毒跟踪技术和量子点，我们已经实时、多色可视化了单个病毒的内吞过程，并全面剖析了甲型流感病毒的两种不同的依赖于网格蛋白或不依赖于网格蛋白的、依赖于动力蛋白的内吞途径。基于蛋白募集和病毒运动的顺序进展，我们揭示了病毒依赖网格蛋白进入过程中网格蛋白和动力蛋白募集的不同步性，大量这两种蛋白的短暂募集事件是无效的。此外，这两种途径中动力蛋白募集的分化持续时间和对抑制剂的反应表明，动力蛋白的作用有所不同。除了促进两种进入途径中的膜分裂外，动力蛋白还参与了网格蛋白依赖途径中网格蛋白包被陷窝的成熟。总的来说，本研究展示了甲型流感病毒进入过程的动态和精确图像，并阐明了不同进入途径的机制。这种基于量子点的单病毒跟踪技术被证明非常适合研究病毒和细胞蛋白之间的协调相互作用。
