Go to The Journal of Clinical Investigation
  • About
  • Editors
  • Consulting Editors
  • For authors
  • Journal stats
  • Publication ethics
  • Publication alerts by email
  • Transfers
  • Advertising
  • Job board
  • Contact
  • Physician-Scientist Development
  • Current issue
  • Past issues
  • By specialty
    • COVID-19
    • Cardiology
    • Immunology
    • Metabolism
    • Nephrology
    • Oncology
    • Pulmonology
    • All ...
  • Videos
  • Collections
    • In-Press Preview
    • Resource and Technical Advances
    • Clinical Research and Public Health
    • Research Letters
    • Editorials
    • Perspectives
    • Physician-Scientist Development
    • Reviews
    • Top read articles

  • Current issue
  • Past issues
  • Specialties
  • In-Press Preview
  • Resource and Technical Advances
  • Clinical Research and Public Health
  • Research Letters
  • Editorials
  • Perspectives
  • Physician-Scientist Development
  • Reviews
  • Top read articles
  • About
  • Editors
  • Consulting Editors
  • For authors
  • Journal stats
  • Publication ethics
  • Publication alerts by email
  • Transfers
  • Advertising
  • Job board
  • Contact
Unbiased cleavage site prediction uncovers viral antagonism of host innate immunity by SARS-CoV-2 3C-like protease
Nora Yucel, Silvia Marchiano, Evan Tchelepi, Germana Paterlini, Ivan A. Kuznetsov, Kristina Li, Quentin McAfee, Nehaar Nimmagadda, Andy Ren, Sam Shi, Alyssa Grogan, Aikaterini Kontrogianni-Konstantopoulos, Charles Murry, Zoltan Arany
Nora Yucel, Silvia Marchiano, Evan Tchelepi, Germana Paterlini, Ivan A. Kuznetsov, Kristina Li, Quentin McAfee, Nehaar Nimmagadda, Andy Ren, Sam Shi, Alyssa Grogan, Aikaterini Kontrogianni-Konstantopoulos, Charles Murry, Zoltan Arany
View: Text | PDF
Research Article COVID-19 Virology

Unbiased cleavage site prediction uncovers viral antagonism of host innate immunity by SARS-CoV-2 3C-like protease

  • Text
  • PDF
Abstract

How SARS-CoV-2 causes a wide range of clinical manifestations and disease severity remains poorly understood. SARS-CoV-2 encodes 2 proteases (3CLPro and PLPro), vital for viral production, but also promiscuous with respect to host protein targets. Pharmacological inhibition of 3CLPro markedly reduced hospitalization and death in Phase 2/3 clinical studies. Here, we develop a bioinformatic algorithm, leveraging experimental data from SARS-CoV, to predict host cleavage targets of 3CLPro. We capture targets of 3CLPro described previously for SARS-CoV-2, as well as thousands of putative targets. We validate numerous targets cleaved during infection, including the giant sarcomeric protein obscurin and the innate immune protein OAS1. A long form of OAS1, p46, has been associated in numerous GWAS studies with lesser COVID disease severity. We show that 3CLPro cleaves p46 OAS1 immediately upstream of a known prenylation domain, relocalizing OAS1 from subcellular membranes to the cytosol, rendering it akin to the nonprotective, cytosolic p42 isoform. Similar OAS1 relocalization occurs upon infection by SARS-CoV-2. Our data provide a high-throughput resource to identify putative host cleavage targets of 3CLPro and reveal a mechanism by which SARS-CoV-2 antagonizes host innate immunity in individuals with the protective p46 isoform of OAS1.

Authors

Nora Yucel, Silvia Marchiano, Evan Tchelepi, Germana Paterlini, Ivan A. Kuznetsov, Kristina Li, Quentin McAfee, Nehaar Nimmagadda, Andy Ren, Sam Shi, Alyssa Grogan, Aikaterini Kontrogianni-Konstantopoulos, Charles Murry, Zoltan Arany

×

Figure 2

Validation of predicted protein targets.

Options: View larger image (or click on image) Download as PowerPoint
Validation of predicted protein targets.
(A) Western blot of in vitro cl...
(A) Western blot of in vitro cleavage of recombinant cadherin with 3CLPro. Shown are cleavage sites within the recombinant fragment, amino acid positions displayed for the full length proteins. Western blots show staining against the C-terminus (His-Tag) of each protein and 3CLPro. Recombinant proteins are a mixture of glycosylated (~90 kDa) and unglycosylated (~65 kda), corresponding to cleavage fragments of ~62 kDa and 40 kDa (respectively). For CADH6 cleavage, 2 formulations of 3CLPro were tested (3CLPro unconjugated, 3CLPro-Maltose-Binding Protein conjugated) at 2 concentrations of protease (+, 0.5 μM; ++, 1 μM). For CADH20 cleavage, only unconjugated 3CLPro digests at 1 μM concentration are shown. For 3CLPro and CADH20 staining (His-Tag), samples were run on the same gel but are noncontiguous (as indicated by line separating lanes). (B) Western blot of in vitro cleavage of purified human α-thrombin (IIa). Diagram shows amino acid position of unprocessed prothrombin. Position of cleavage site shown with respect to epitope of antibody used for Western blot. In total, 1 μM of purified 3CLPro was incubated with 2 μg α-thrombin overnight under reducing conditions, with or without the 3CLPro inhibitor GC376 (1 μM). (C) In vitro cleavage of purified recombinant NOTCH1 fragment (aa 2280–2550) with a N-terminal His-Tag. Reactions were done with 1 μM of purified 3CLPro for 1 hour. Diagram shows position of cleavage within the NOTCH1 fragment, with amino acid positions corresponding to the full-length protein. Epitope regions showed for antibody with epitope C-terminal to the cleavage site. Full-length size is ~29 kDa, with N and C-terminal fragments of 4 kDa and 25 kDa (respectively). Samples were run on the same gel but are noncontiguous. (D) Cellular cleavage of NOTCH1. Western blots show lysates of hIPSC cardiomyocytes expressing 3CLPro or catalytically inactive C145A variant for 48 hours. Cleavage site position within the intracellular fragment of NOTCH1 shown, as well as epitope for antibody used in Western blot.

Copyright © 2026 American Society for Clinical Investigation
ISSN 2379-3708

Sign up for email alerts