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Updated: Jun 7, 2025
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Visualization of SARS-CoV-2 using Immuno RNA-Fluorescence In Situ Hybridization
Published on: December 23, 2020
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SARS-CoV-2 Displays a Suboptimal Codon Usage Bias for Efficient Translation in Human Cells Diverted by Hijacking the
Patrick Eldin1, Alexandre David2,3, Christophe Hirtz3
1Institut de Recherche en Infectiologie de Montpellier (IRIM), University of Montpellier, CNRS UMR 9004, 1919 route de Mende, 34293 Montpellier, France.
International Journal of Molecular Sciences
|November 9, 2024
Summary
SARS-CoV-2 exhibits codon bias, favoring codons infrequent in humans. The virus likely manipulates host tRNA modifications to enhance its translation and replication within human cells.
Area of Science:
- Virology
- Molecular Biology
- Genetics
Background:
- SARS-CoV-2 displays significant codon bias, utilizing codons rarely found in human genes.
- This bias suggests suboptimal adaptation for efficient translation within human host cells.
Purpose of the Study:
- To investigate the codon bias of SARS-CoV-2.
- To explore the role of tRNA modifications in SARS-CoV-2 translation and replication.
Main Methods:
- Codon bias analysis of SARS-CoV-2 genome.
- LC-MS/MS quantification of tRNA modifications.
- Alteration of enzymatic tRNA modification pathways.
Main Results:
- SARS-CoV-2 preferentially uses Lys(AAA), Gln(CAA), Glu(GAA), and Arg(AGA) codons.
- Efficient decoding of these codons requires mcm5s2 modification at the U34 wobble position of specific tRNAs.
- Experimental evidence supports SARS-CoV-2's induction of U34 tRNA modifications for its lifecycle.
Conclusions:
- SARS-CoV-2 likely manipulates host tRNA modifications to optimize translation of its biased genome.
- Further research is needed on the evolution of SARS-CoV-2 codon bias and its impact on host tRNA pools.
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