《Nature,8月17日,Structures and distributions of SARS-CoV-2 spike proteins on intact virions》

  • 来源专题:COVID-19科研动态监测
  • 编译者: zhangmin
  • 发布时间:2020-09-02
  • Structures and distributions of SARS-CoV-2 spike proteins on intact virions

    Zunlong Ke, Joaquin Oton, Kun Qu, Mirko Cortese, Vojtech Zila, Lesley McKeane, Takanori Nakane, Jasenko Zivanov, Christopher J. Neufeldt, Berati Cerikan, John M. Lu, Julia Peukes, Xiaoli Xiong, Hans-Georg Kräusslich, Sjors H. W. Scheres, Ralf Bartenschlager & John A. G. Briggs

    Nature (2020)

    Abstract

    Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virions are surrounded by a lipid bilayer from which spike (S) protein trimers protrude1. Heavily glycosylated S trimers bind the ACE2 receptor and mediate entry of virions into target cells2–6. S exhibits extensive conformational flexibility: it modulates exposure of its receptor binding site and later undergoes complete structural rearrangement to drive fusion of viral and cellular membranes2,7,8. The structures and conformations of soluble, overexpressed, purified S proteins have been studied in detail using cryo-electron microscopy2,7,9–12. The structure and distribution of S on the virion surface, however, has not been characterized. Here we applied cryo-electron microscopy and tomography to image intact SARS-CoV-2 virions, determining the high-resolution structure, conformational flexibility and distribution of S trimers in situ on the virion surface. These results reveal the conformations of S present on the virion, and provide a basis from which to understand interactions between S and neutralizing antibodies during infection or vaccination.

  • 原文来源:https://www.nature.com/articles/s41586-020-2665-2
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    • 来源专题:COVID-19科研动态监测
    • 编译者:zhangmin
    • 发布时间:2020-10-13
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    • 来源专题:COVID-19科研动态监测
    • 编译者:zhangmin
    • 发布时间:2020-03-18
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