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

本项目的目标是：1)使用HS-AFM记录生理条件下的天然病毒融合蛋白的构象；2)使用HS-AFM观察酸性条件引发的构象变化中的快速和瞬时中间产物；3)利用HS-AFM了解病毒融合蛋白与外体或抗体相互作用时的构象动态。PI已经使用HS-AFM对SARS-CoV-2刺突(S)蛋白与中和抗体相互作用过程中的结构动力学进行了纳米级阐明(目标3)。某些中和抗体促进RBD从封闭构象到开放确认的转变，以增强RBD-ACE2的相互作用。这种效应被称为抗体依赖增强效应(ADE)。这项研究表明，HS-AFM可以作为S NAB测试的有效纳米级评估平台。这项研究已经发表在声誉良好的杂志《纳米快报》上。此外，这项研究还在国内几次会议上发表过。登革病毒的包膜蛋白(E蛋白)将在不久的将来进行研究。

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.