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Bacterial Artificial Chromosomes: A Functional Genomics Tool for the Study of Positive-strand RNA Viruses
Published on: December 29, 2015
Coronaviruses reprogram the tRNA epitranscriptome to favor viral protein expression
Elena Muscolino1, Mireia Puig-Torrents1, Jaime Buigues Bisquert2
1Molecular Virology group, Department of Medicine and Life Sciences, Universitat Pompeu Fabra, Barcelona, Spain.
Nature Communications
|February 19, 2026
Summary
Coronaviruses use specific tRNA modifications to efficiently translate their genomes, despite using suboptimal codons. Viral infections reprogram these modifications, offering a potential target for antiviral therapies.
Area of Science:
- Molecular Biology
- Virology
- Genomics
Background:
- Coronaviruses utilize suboptimal codons, potentially hindering protein synthesis due to limited tRNA availability.
- The mechanism by which coronaviruses achieve efficient protein expression despite codon bias is not fully understood.
Purpose of the Study:
- To investigate the role of tRNA modifications in coronavirus protein synthesis.
- To identify specific tRNA modifications essential for decoding suboptimal codons used by coronaviruses.
- To explore how viral infections, such as SARS-CoV-2 and HCoV-OC43, alter tRNA modifications.
Main Methods:
- Analysis of coronavirus codon usage patterns.
- Identification of key tRNA modifications (inosine, queuosine, mcm5U/mcm5s2U, m5C/f5C).
- Investigation of tRNA modifying enzyme expression during viral infections.
Main Results:
- Four specific tRNA modifications are crucial for decoding suboptimal viral codons.
- SARS-CoV-2 and HCoV-OC43 infections reprogram these tRNA modifications to enhance viral protein synthesis.
- Viral reprogramming of tRNA modifications is linked to altered expression of tRNA modifying enzymes.
Conclusions:
- Coronaviruses adapt to the host tRNA modification landscape, particularly under stress conditions.
- This codon-specific reprogramming optimizes viral translation efficiency.
- Targeting tRNA modification pathways presents a potential strategy for pan-coronavirus antiviral development.
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