Language
English
Publication Date
11-1-2025
Journal
Nature Microbiology
DOI
10.1038/s41564-025-02138-w
PMID
41093992
PMCID
PMC12570964
PubMedCentral® Posted Date
10-15-2025
PubMedCentral® Full Text Version
Post-print
Abstract
Recognition of foreign RNA is critical for the innate immune response to viruses. Interferon (IFN)-induced proteins with tetratricopeptide repeats (IFIT) 2 and 3 are highly upregulated following viral infection, but mechanistic insight into their antiviral role is lacking. Here we demonstrate that short 5' untranslated regions (UTRs), a characteristic of many viral mRNAs, can serve as a molecular pattern for innate immune recognition via IFIT2 and IFIT3. Structure determination of the IFIT2-IFIT3 complex at 3.2 Å using cryo-EM reveals a domain-swapped heterodimer that is required for recognition of the viral mRNA 5' end, translation inhibition and antiviral activity. Critically, viral or host 5' UTR lengths less than 50 nucleotides are necessary and sufficient to enable translation inhibition by the IFIT2-IFIT3 complex. Accordingly, diverse viruses whose mRNAs contain short 5' UTRs, such as vesicular stomatitis virus and parainfluenza virus 3, are sensitive to IFIT2-IFIT3-mediated antiviral activity. Our work thus reveals a pattern of antiviral nucleic acid immune recognition that takes advantage of the inherent constraints on viral genome size.
Keywords
5' Untranslated Regions, Humans, RNA, Viral, Protein Biosynthesis, RNA-Binding Proteins, RNA, Messenger, Immunity, Innate, Intracellular Signaling Peptides and Proteins, HEK293 Cells, Cryoelectron Microscopy, Carrier Proteins, Apoptosis Regulatory Proteins, Viral host response, Virus-host interactions, Interferons, Innate immunity, Viral infection
Published Open-Access
yes
Recommended Citation
Glasner, Dustin R; Todd, Candace; Cook, Brian; et al., "The IFIT2-IFIT3 Antiviral Complex Targets Short 5′ Untranslated Regions on Viral mRNAs for Translation Inhibition" (2025). Faculty, Staff and Students Publications. 6407.
https://digitalcommons.library.tmc.edu/baylor_docs/6407