Inhibition of SARS-CoV-2 viral entry upon blocking N- and O-glycan elaboration

  1. Qi Yang
  2. Thomas A Hughes
  3. Anju Kelkar
  4. Xinheng Yu
  5. Kai Cheng
  6. Sheldon Park
  7. Wei-Chiao Huang
  8. Jonathan F Lovell
  9. Sriram Neelamegham  Is a corresponding author
  1. State University of New York at Buffalo, United States

Abstract

The Spike protein of SARS-CoV-2, its receptor binding domain (RBD), and its primary receptor ACE2 are extensively glycosylated. The impact of this post-translational modification on viral entry is yet unestablished. We expressed different glycoforms of the Spike-protein and ACE2 in CRISPR-Cas9 glycoengineered cells, and developed corresponding SARS-CoV-2 pseudovirus. We observed that N- and O-glycans had only minor contribution to Spike-ACE2 binding. However, these carbohydrates played a major role in regulating viral entry. Blocking N-glycan biosynthesis at the oligomannose stage using both genetic approaches and the small molecule kifunensine dramatically reduced viral entry into ACE2 expressing HEK293T cells. Blocking O-glycan elaboration also partially blocked viral entry. Mechanistic studies suggest multiple roles for glycans during viral entry. Among them, inhibition of N-glycan biosynthesis enhanced Spike-protein proteolysis. This could reduce RBD presentation on virus, lowering binding to host ACE2 and decreasing viral entry. Overall, chemical inhibitors of glycosylation may be evaluated for COVID-19.

Data availability

All data generated or analysed during this study are included in the manuscript and supporting files. All plasmids generated by the authors will be deposited at Addgene.

Article and author information

Author details

  1. Qi Yang

    Department of Chemical and Biological Engineering, State University of New York at Buffalo, Buffalo, United States
    Competing interests
    Qi Yang, Co-author of a provisional patent application.(63/079,667).
  2. Thomas A Hughes

    Department of Chemical and Biological Engineering, State University of New York at Buffalo, Buffalo, United States
    Competing interests
    Thomas A Hughes, Co-author of a provisional patent application.(63/079,667).
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-7887-6876
  3. Anju Kelkar

    Department of Chemical and Biological Engineering, State University of New York at Buffalo, Buffalo, United States
    Competing interests
    Anju Kelkar, Co-author of a provisional patent application.(63/079,667).
  4. Xinheng Yu

    Department of Chemical and Biological Engineering, State University of New York at Buffalo, Buffalo, United States
    Competing interests
    No competing interests declared.
  5. Kai Cheng

    Department of Chemical and Biological Engineering, State University of New York at Buffalo, Buffalo, United States
    Competing interests
    No competing interests declared.
  6. Sheldon Park

    Department of Chemical and Biological Engineering, State University of New York at Buffalo, Buffalo, United States
    Competing interests
    No competing interests declared.
  7. Wei-Chiao Huang

    Department of Biomedical Engineering, State University of New York at Buffalo, Buffalo, United States
    Competing interests
    No competing interests declared.
  8. Jonathan F Lovell

    Department of Biomedical Engineering, State University of New York at Buffalo, Buffalo, United States
    Competing interests
    No competing interests declared.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-9052-884X
  9. Sriram Neelamegham

    Department of Chemical and Biological Engineering, State University of New York at Buffalo, Buffalo, United States
    For correspondence
    neel@buffalo.edu
    Competing interests
    Sriram Neelamegham, Co-author of a provisional patent application.(63/079,667).
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-1371-8500

Funding

National Institutes of Health (HL103411)

  • Sriram Neelamegham

National Institutes of Health (GM133195)

  • Sriram Neelamegham

National Institutes of Health (GM126537)

  • Sriram Neelamegham

National Institutes of Health (GM139160)

  • Sheldon Park
  • Sriram Neelamegham

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Reviewing Editor

  1. Malcolm J McConville, The University of Melbourne, Australia

Publication history

  1. Received: July 29, 2020
  2. Accepted: October 24, 2020
  3. Accepted Manuscript published: October 26, 2020 (version 1)
  4. Version of Record published: November 24, 2020 (version 2)

Copyright

© 2020, Yang et al.

This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.

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  1. Qi Yang
  2. Thomas A Hughes
  3. Anju Kelkar
  4. Xinheng Yu
  5. Kai Cheng
  6. Sheldon Park
  7. Wei-Chiao Huang
  8. Jonathan F Lovell
  9. Sriram Neelamegham
(2020)
Inhibition of SARS-CoV-2 viral entry upon blocking N- and O-glycan elaboration
eLife 9:e61552.
https://doi.org/10.7554/eLife.61552
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