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Updated: Oct 23, 2025
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Bacterial Artificial Chromosomes: A Functional Genomics Tool for the Study of Positive-strand RNA Viruses
Published on: December 29, 2015
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Cotranslational prolyl hydroxylation is essential for flavivirus biogenesis
Ranen Aviner1,2, Kathy H Li3, Judith Frydman4
1Department of Microbiology and Immunology, University of California, San Francisco, San Francisco, CA, USA.
Nature
|August 19, 2021
Summary
Viruses like polio, dengue, and Zika hijack host cell machinery by altering protein-making complexes called polysomes. Targeting these viral polysomes offers a novel antiviral strategy.
Area of Science:
- Virology
- Molecular Biology
- Biochemistry
Background:
- Viral pathogens pose a significant global public health threat.
- Understanding virus-host interactions is crucial for developing antiviral therapies.
- Host biosynthetic pathways are essential for viral replication.
Purpose of the Study:
- To investigate how enteroviruses and flaviviruses remodel host polysomes.
- To identify host machineries exploited by viruses for protein synthesis.
- To explore targeting viral polysomes as an antiviral strategy.
Main Methods:
- Proteomic analysis of polysomes.
- Functional genomics.
- Pharmacological interventions.
- Analysis of viral protein modification.
Main Results:
- Viral infection (polio, dengue, Zika) alters polysome composition without changing ribosome stoichiometry.
- Viruses evict common translation factors and recruit specific host machinery.
- Zika and dengue viruses utilize collagen proline hydroxylation for viral polyprotein modification.
- Inhibition of proline hydroxylation impairs viral polyprotein folding and reduces virus production.
Conclusions:
- Viral polysome remodeling is a modular process at the virus-host interface.
- Targeting specialized viral polysomes presents a promising antiviral intervention approach.
- Proline hydroxylation is a key host factor exploited by dengue and Zika viruses.
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