Real-time observation of native conformations and molecular behaviors of viral fusion proteins using high-speed atomic force microscopy (HS-AFM)

本项目的主要目的是：1）利用HS-AFM记录病毒融合蛋白在生理条件下的天然构象; 2）利用HS-AFM观察病毒融合蛋白在酸性条件下快速和短暂的构象变化; 3）利用HS-AFM研究病毒融合蛋白与exosome或抗体相互作用时的构象动态。PI已实施HS-AFM，以在SARS-CoV-2刺突（S）蛋白与中和抗体相互作用期间对其结构动力学进行纳米级阐明（目标3）。某些中和抗体促进RBD从其封闭构象转变为开放构象以增强RBD-ACE 2相互作用。这种效应被称为抗体依赖性增强效应（ADE）。这项研究表明，HS-AFM可以作为一个有效的纳米尺度评估平台的S NAb测试。这项研究发表在著名的期刊《纳米快报》上。此外，该研究还在国内的几个会议上发表。登革病毒E蛋白是登革病毒的主要包膜蛋白。

The objectives of this project are: 1) to record the native conformation viral fusion proteins under physiological conditions using HS-AFM; 2) to visualize the rapid and transient intermediates during conformational changes triggered by acidic conditions using HS-AFM; 3) to elucidate the conformational dynamic of viral fusion proteins when interacting with exosomes or antibodies using HS-AFM. The PI has implemented HS-AFM to perform nanoscopic elucidation of SARS-CoV-2 spike (S) protein structural dynamics during its interaction with neutralizing antibodies (Objective 3). Certain neutralizing antibodies promote the transition of RBD from its close conformation to open confirmation to enhance RBD-ACE2 interaction. This effect is known as antibody-dependent enhancement effect (ADE). This study reveals that HS-AFM could be worked as an efficient nanoscopic assessment platform for S NAb testing. This study has been published in a well-reputed journal, Nano Letters. Furthermore, this study has also been presented in several domestic conferences. Envelope protein (E protein) of Dengue virus will be investigated in the near future.