Back to Search
Start Over
SARS-CoV-2 Uses Nonstructural Protein 16 To Evade Restriction by IFIT1 and IFIT3
- Source :
- Journal of virology, vol 97, iss 2, bioRxiv
- Publication Year :
- 2023
- Publisher :
- eScholarship, University of California, 2023.
-
Abstract
- Understanding the molecular basis of innate immune evasion by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is an important consideration for designing the next wave of therapeutics. Here, we investigate the role of the nonstructural protein 16 (NSP16) of SARS-CoV-2 in infection and pathogenesis. NSP16, a ribonucleoside 2’-O methyltransferase (MTase), catalyzes the transfer of a methyl group to mRNA as part of the capping process. Based on observations with other CoVs, we hypothesized that NSP16 2’-O MTase function protects SARS-CoV-2 from cap-sensing host restriction. Therefore, we engineered SARS-CoV-2 with a mutation that disrupts a conserved residue in the active site of NSP16. We subsequently show that this mutant is attenuated both in vitro and in vivo, using a hamster model of SARS-CoV-2 infection. Mechanistically, we confirm that the NSP16 mutant is more sensitive to type I interferon (IFN-I) in vitro. Furthermore, silencing IFIT1 or IFIT3, IFN-stimulated genes that sense a lack of 2’-O methylation, partially restores fitness to the NSP16 mutant. Finally, we demonstrate that sinefungin, a methyltransferase inhibitor that binds the catalytic site of NSP16, sensitizes wild-type SARS-CoV-2 to IFN-I treatment. Overall, our findings highlight the importance of SARS-CoV-2 NSP16 in evading host innate immunity and suggest a possible target for future antiviral therapies.ImportanceSimilar to other coronaviruses, disruption of SARS-CoV-2 NSP16 function attenuates viral replication in a type I interferon-dependent manner. In vivo, our results show reduced disease and viral replication at late times in the hamster lung, but an earlier titer deficit for the NSP16 mutant (dNSP16) in the upper airway. In addition, our results confirm a role for IFIT1, but also demonstrate the necessity of IFIT3 in mediating dNSP16 attenuation. Finally, we show that targeting NSP16 activity with a 2’-O methyltransferase inhibitor in combination with type I interferon offers a novel avenue for antiviral development.
- Subjects :
- Immunology
NSP16
coronavirus
interferon-stimulated gene
Viral Nonstructural Proteins
Microbiology
Medical and Health Sciences
Article
Vaccine Related
IFIT3
IFIT1
Cricetinae
Biodefense
Virology
antiviral agents
Animals
2.1 Biological and endogenous factors
Aetiology
Lung
Agricultural and Veterinary Sciences
SARS-CoV-2
Prevention
Intracellular Signaling Peptides and Proteins
Signal Transducing
Adaptor Proteins
RNA-Binding Proteins
COVID-19
Methyltransferases
Pneumonia
2'-O-methyltransferase
Biological Sciences
Emerging Infectious Diseases
Infectious Diseases
Good Health and Well Being
Insect Science
Interferon Type I
Pneumonia & Influenza
Respiratory
Infection
Biotechnology
Subjects
Details
- Database :
- OpenAIRE
- Journal :
- Journal of virology, vol 97, iss 2, bioRxiv
- Accession number :
- edsair.doi.dedup.....efc3b14dd84ecc851034f4895dcc1263