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Updated: Aug 2, 2026
18:10
Isolation of Fidelity Variants of RNA Viruses and Characterization of Virus Mutation Frequency
Published on: June 16, 2011
Quasispecies development by high frequency RNA recombination during MHV persistence
C L Rowe1, S C Baker, M J Nathan
1Department of Microbiology and Immunology, Loyola University of Chicago, Stritch School of Medicine, Maywood, Illinois 60153, USA.
Advances in Experimental Medicine and Biology
|October 23, 1998
Summary
Persistent viral RNA populations, known as quasispecies, are linked to severe disease. This study found that complex viral quasispecies in mice with chronic paralysis correlate with specific RNA deletions, suggesting a role in pathogenesis.
Area of Science:
- Virology
- Molecular Biology
- Immunology
Background:
- Infectious viruses, particularly persisting viral RNAs, often exist as diverse populations termed "quasispecies".
- Understanding the role of viral quasispecies in pathogenesis is crucial for developing effective treatments.
Purpose of the Study:
- To characterize viral quasispecies populations during persistent mouse hepatitis virus (MHV) infection.
- To investigate the association between viral quasispecies complexity and MHV-induced pathogenesis.
Main Methods:
- Analysis of persisting viral RNA populations using reverse-transcription polymerase chain reaction (RT-PCR) of the spike gene's S1 region.
- Differential colony hybridization to identify spike deletion variants (SDVs).
- Sequence analysis of SDVs and mapping to predicted RNA secondary structures.
Main Results:
- Mice exhibiting the most severe chronic paralysis harbored the most complex viral quasispecies.
- A frequently deleted structural motif in the spike RNA was identified as an isolated stem loop structure.
- High-frequency recombination at sites of RNA secondary structure appears to drive viral quasispecies expansion.
Conclusions:
- Viral quasispecies complexity is associated with the severity of persistent MHV infection.
- Specific RNA secondary structures may serve as recombination hotspots, contributing to viral evolution and pathogenesis.
- These findings provide insights into the mechanisms underlying persistent viral infections and disease progression.
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