Subversion of innate antiviral immunity by SARS-CoV-2: An example from the study of nonstructural protein 16.
| dc.contributor.advisor | Menachery, Vineet | |
| dc.contributor.committeeMember | Endsley, Janice | |
| dc.contributor.committeeMember | Makino, Shinji | |
| dc.contributor.committeeMember | Rajsbaum, Ricardo | |
| dc.contributor.committeeMember | Daugherty, Matthew | |
| dc.creator | Schindewolf, Craig Daniel 1987- | |
| dc.creator.orcid | 0000-0002-9804-2246 | |
| dc.date.accessioned | 2023-02-23T19:01:25Z | |
| dc.date.available | 2023-02-23T19:01:25Z | |
| dc.date.created | 2022-12 | |
| dc.date.issued | 2022-12-01T06:00:00.000Z | |
| dc.date.submitted | December 2022 | |
| dc.date.updated | 2023-02-23T19:01:27Z | |
| dc.description.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 (NSP) 16 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. Conversely, overexpressing IFIT1 either alone or in combination with IFIT3 attenuates the NSP16 mutant relative to wild-type. Finally, we demonstrate that sinefungin, a MTase inhibitor that binds the catalytic site of NSP16, sensitizes wild-type SARS-CoV-2 to IFN-I treatment and attenuates viral replication in IFN-I competent cells. Overall, our findings highlight the importance of SARS-CoV-2 NSP16 to evading host innate immunity and suggest a possible target for future antiviral therapies. | |
| dc.format.mimetype | application/pdf | |
| dc.identifier.uri | ||
| dc.identifier.uri | https://hdl.handle.net/2152.3/11878 | |
| dc.language.iso | English | |
| dc.title | Subversion of innate antiviral immunity by SARS-CoV-2: An example from the study of nonstructural protein 16. | |
| dc.type | Thesis | |
| dc.type.material | text | |
| thesis.degree.college | UTMB Graduate School of Biomedical Sciences | |
| thesis.degree.department | Microbiology and Immunology | |
| thesis.degree.discipline | Microbiology and Immunology | |
| thesis.degree.grantor | The University of Texas Medical Branch at Galveston | |
| thesis.degree.name | Microbiology and Immunology (Doctoral) | |
| thesis.degree.school | University of Texas Medical Branch at Galveston |