SARS-CoV-2 3CLpro (main protease) regulates caspase activation of gasdermin-D/E pores leading to secretion and extracellular activity of 3CLpro
SARS-CoV-2 3C-like protease (3CL<sup>pro</sup> or M<sup>pro</sup>) cleaves the SARS-CoV-2 polyprotein and >300 intracellular host proteins to enhance viral replication. By lytic cell death following gasdermin (GSDM) pore formation in cell membranes, antiviral pyroptosis decreases 3CL<sup>pro</sup> expression and viral replication. Unexpectedly, 3CL<sup>pro</sup> and nucleocapsid proteins undergo unconventional secretion from infected cells via caspase-activated GSDMD/E pores in the absence of cell lysis. Bronchoalveolar lavage fluid of wild-type SARS-CoV-2-infected mice contains 3CL<sup>pro</sup>, which decreases in Gsdmd<sup>-/-</sup>Gsdme<sup>-/-</sup> mice. We identify new 3CL<sup>pro</sup> cut-sites in GSDMD at LQ<sup>29</sup>↓<sup>30</sup>SS, which blocks pore formation by 3CL<sup>pro</sup> cleavage at LH<sup>270</sup>↓N lying adjacent to the caspase activation site (NFLTD<sup>275</sup>↓G). Cleavage inactivation of GSDMD prevents excessive pore formation, thus countering antiviral pyroptosis and increasing 3CL<sup>pro</sup> secretion. Extracellular 3CL<sup>pro</sup> retains activity in serum, dampens platelet activation and aggregation, and inactivates antiviral interferon-λ1. Thus, in countering gasdermin pore formation and pyroptosis in SARS-CoV-2 infection, 3CL<sup>pro</sup> is secreted with extracellular pathological sequelae.
Authors
- John C. Vederas (ORCID: https://orcid.org/0000-0002-2996-0326)
- Steven Z. Jiang (ORCID: https://orcid.org/0009-0000-7630-3612)
- Isabel Pablos (ORCID: https://orcid.org/0000-0001-8052-3853)
- Yoan Machado (ORCID: https://orcid.org/0000-0002-8251-3744)
- Charaf Benarafa (ORCID: https://orcid.org/0000-0002-2049-7769)
- Reinhild Kappelhoff (ORCID: https://orcid.org/0000-0001-9810-7751)
- Peter M. Grin (ORCID: https://orcid.org/0000-0001-9504-9664)
- Christina L. Pan
- Arinjay Banerjee (ORCID: https://orcid.org/0000-0002-2821-8357)
- Christopher M. Overall (ORCID: https://orcid.org/0000-0001-5844-2731)
- Hugh Kim
- Hugo César Ramos de Jesus (ORCID: https://orcid.org/0000-0001-8223-094X)
- Kaushal Baid (ORCID: https://orcid.org/0000-0002-4354-7941)
- Nathan Georges François Leborgne (ORCID: https://orcid.org/0000-0002-1405-1023)
- Peter A. Bell (ORCID: https://orcid.org/0000-0001-6143-5444)
- Nedim Kozarac (ORCID: https://orcid.org/0009-0001-1038-9991)
- Georgina S. Butler (ORCID: https://orcid.org/0000-0003-1172-1578)
Institutions
- University of Bern (CH)
- University of British Columbia (CA)
- University of Alberta (CA)
- Vancouver Hospital and Health Sciences Centre (CA)
- University of Saskatchewan (CA)
Publication Details
- Journal
- Cell Reports
- Published
- 2024-12-01
- DOI
- https://doi.org/10.1016/j.celrep.2024.115080
- Citations
- 7
- Primary Topic
- Inflammasome and immune disorders
- Type
- article
- Field-Weighted Citation Impact
- 1.64
Funders
- National Science Foundation
- Arthritis Society
- Canada Foundation for Innovation
- Michael Smith Health Research BC
- Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung
- Canada Research Chairs
- University of British Columbia
- Centre for Blood Research, University of British Columbia
- Canadian Institutes of Health Research