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18:10
Isolation of Fidelity Variants of RNA Viruses and Characterization of Virus Mutation Frequency
Published on: June 16, 2011
Evolution of mutational robustness in an RNA virus
Rebecca Montville1, Remy Froissart, Susanna K Remold
1Department of Ecology and Evolutionary Biology, Yale University, New Haven, Connecticut, United States of America.
Plos Biology
|October 27, 2005
Summary
Selection for genetic robustness in RNA viruses weakens with increased co-infection frequency. This study shows viruses evolved under high co-infection exhibit reduced robustness, impacting their evolution and replication accuracy.
Area of Science:
- Evolutionary Biology
- Virology
- Genetics
Background:
- Mutational robustness, or phenotypic stability despite genetic changes, is crucial for natural selection.
- Evidence for the adaptive evolution of mutational robustness in populations is debated.
- High mutation rates in RNA viruses suggest robustness should be favored, but co-infection may relax this selection.
Purpose of the Study:
- To investigate how co-infection frequency affects the selection for genetic robustness in RNA viruses.
- To test the hypothesis that increased co-infection weakens selection for robustness.
Main Methods:
- Experimental evolution of RNA phage phi6 populations at low and high co-infection levels.
- Mutation accumulation experiments using population bottlenecking.
- Quantification of fitness changes following random mutations.
Main Results:
- Viruses evolved under high co-infection showed greater mean magnitude and variance in fitness changes from mutations.
- This indicates weakened selection for robustness in high co-infection scenarios.
- Higher mutation frequencies were observed in more robust viruses.
Conclusions:
- Co-infection may offer short-term advantages to RNA viruses but weakens selection for genetic robustness.
- The evolution of robustness in RNA viruses might be linked to less accurate genome replication.
- Understanding these dynamics is key to viral evolution and disease.
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