CAS Key Laboratory of Special Pathogens and Biosafety, Center for Biosafety Mega-Science, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, 430071, China.
Department of Gastroenterology, Wuhan Children's Hospital, Tongji Medical College, Huazhong University of Science and Technology, 430015, Wuhan, China.
J Nanobiotechnology. 2021 Sep 28;19(1):295. doi: 10.1186/s12951-021-01046-5.
Fluorescent labeling and dynamic tracking is a powerful tool for exploring virus infection mechanisms. However, for small-sized viruses, virus tracking studies are usually hindered by a lack of appropriate labeling methods that do not dampen virus yield or infectivity. Here, we report a universal strategy for labeling viruses with chemical dyes and Quantum dots (QDs). Enterovirus 71 (EV71) was produced in a cell line that stably expresses a mutant methionyl-tRNA synthetase (MetRS), which can charge azidonorleucine (ANL) to the methionine sites of viral proteins during translation. Then, the ANL-containing virus was easily labeled with DBCO-AF647 and DBCO-QDs. The labeled virus shows sufficient yield and no obvious decrease in infectivity and can be used for imaging the virus entry process. Using the labeled EV71, different functions of scavenger receptor class B, member 2 (SCARB2), and heparan sulfate (HS) in EV71 infection were comparatively studied. The cell entry process of a strong HS-binding EV71 strain was investigated by real-time dynamic visualization of EV71-QDs in living cells. Taken together, our study described a universal biocompatible virus labeling method, visualized the dynamic viral entry process, and reported details of the receptor usage of EV71.
荧光标记和动态追踪是探索病毒感染机制的有力工具。然而，对于小尺寸的病毒，病毒追踪研究通常受到缺乏适当标记方法的限制，这些方法不会抑制病毒产量或感染力。在这里，我们报告了一种用化学染料和量子点（QDs）标记病毒的通用策略。肠道病毒 71 型（EV71）在稳定表达突变甲硫氨酰-tRNA 合成酶（MetRS）的细胞系中产生，该酶在翻译过程中可以将叠氮基正亮氨酸（ANL）加载到病毒蛋白的甲硫氨酸位点。然后，用 DBCO-AF647 和 DBCO-QDs 轻松标记含 ANL 的病毒。标记后的病毒产量充足，感染力无明显下降，可用于成像病毒进入过程。使用标记的 EV71，比较研究了清道夫受体 B 类成员 2（SCARB2）和肝素硫酸酯（HS）在 EV71 感染中的不同功能。通过实时动态可视化活细胞中的 EV71-QDs，研究了强 HS 结合 EV71 株的细胞进入过程。综上所述，我们的研究描述了一种通用的生物相容性病毒标记方法，可视化了病毒的动态进入过程，并报道了 EV71 受体使用的详细信息。
