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Updated: Jul 3, 2026
08:58
In Vitro Transcribed RNA-based Luciferase Reporter Assay to Study Translation Regulation in Poxvirus-infected Cells
Published on: May 1, 2019
Translational termination-re-initiation in viral systems
Michael L Powell1, T David K Brown, Ian Brierley
1Division of Virology, Department of Pathology, University of Cambridge, Cambridge, UK. mlp34@cam.ac.uk
Biochemical Society Transactions
|July 18, 2008
Summary
Viruses use termination-dependent re-initiation to control protein expression from polycistronic mRNAs. This mechanism couples upstream and downstream open reading frames (ORFs) for efficient viral protein synthesis.
Area of Science:
- Molecular Biology
- Virology
- Genetics
Background:
- Viruses employ diverse strategies to regulate viral protein synthesis from polycistronic mRNAs.
- Mechanisms like programmed ribosomal frameshifting and stop codon readthrough are established.
- Termination-dependent re-initiation (stop-start) is an emerging translational control mechanism.
Purpose of the Study:
- To review the regulation of termination-dependent re-initiation in viral systems.
- To explore the coupling of upstream and downstream open reading frames (ORFs).
- To highlight differences in re-initiation mechanisms across prokaryotic, eukaryotic, and viral mRNAs.
Main Methods:
- Literature review of viral translational control mechanisms.
- Analysis of mRNA structures and translation initiation/termination signals.
- Comparative analysis of re-initiation across different biological systems.
Main Results:
- Termination-dependent re-initiation couples the expression of ORFs.
- The stop codon of an upstream ORF (uORF) is proximal to the start codon of a downstream ORF.
- Influenza B virus mRNA provides an example of overlapping stop-start codons.
Conclusions:
- Termination-dependent re-initiation is a key viral strategy for regulating protein expression.
- Understanding this mechanism is crucial for comprehending viral gene expression.
- Comparative analysis reveals conserved and distinct features of re-initiation across life domains.
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