Intermediates in SARS-CoV-2 spike–mediated cell entry

Authors

Tara C. Marcink, Department of Pediatrics, Columbia University Vagelos College of Physicians and Surgeons, New York, NY
Thomas Kicmal, Department of Microbiology and Immunology, Loyola University Chicago, Maywood, IL
Emily Armbruster, CUNY Advanced Science Research CenterFollow
Zhening Zhang, Department of Biochemistry and Molecular Biophysics, Columbia University Vagelos College of Physicians and Surgeons, New York, NY
Gillian Zipursky, Department of Pediatrics, Columbia University Vagelos College of Physicians and Surgeons, New York, NY
Kate L. Golub, Department of Pediatrics, Columbia University Vagelos College of Physicians and Surgeons, New York, NY
Mohab Idris, Department of Pediatrics, Columbia University Vagelos College of Physicians and Surgeons, New York, NY
Jonathan Khao, Digizyme Inc., Brookline, MA
Jennifer Drew-Bear, Department of Pediatrics, Columbia University Vagelos College of Physicians and Surgeons, New York, NY
Gael McGill, Digizyme Inc., Brookline, MA
Tom Gallagher, Department of Microbiology and Immunology, Loyola University Chicago, Maywood, ILFollow
Matteo Porotto, Department of Pediatrics, Columbia University Vagelos College of Physicians and Surgeons, New York, NYFollow
Amédée des Georges, CUNY Advanced Science Research CenterFollow
Anne Moscona, Department of Pediatrics, Columbia University Vagelos College of Physicians and Surgeons, New York, NYFollow

Document Type

Article

Publication Date

8-19-2022

Abstract

SARS-CoV-2 cell entry is completed after viral spike (S) protein–mediated membrane fusion between viral and host cell membranes. Stable prefusion and postfusion S structures have been resolved by cryo–electron microscopy and cryo–electron tomography, but the refolding intermediates on the fusion pathway are transient and have not been examined. We used an antiviral lipopeptide entry inhibitor to arrest S protein refolding and thereby capture intermediates as S proteins interact with hACE2 and fusion-activating proteases on cell-derived target membranes. Cryo–electron tomography imaged both extended and partially folded intermediate states of S2, as well as a novel late-stage conformation on the pathway to membrane fusion. The intermediates now identified in this dynamic S protein–directed fusion provide mechanistic insights that may guide the design of CoV entry inhibitors.

Comments

This article was originally published in Science Advances, available at http://dx.doi.org/10.1126/sciadv.abo3153

This work is distributed under a Creative Commons Attribution-NonCommercial 4.0 International License (CC BY-NC 4.0).