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Updated: Jul 11, 2026
18:10
Isolation of Fidelity Variants of RNA Viruses and Characterization of Virus Mutation Frequency
Published on: June 16, 2011
Levels of selection in positive-strand virus dynamics
1Santa Fe Institute, Santa Fe, NM 87501, USA. krakauer@santafe.edu
Journal of Evolutionary Biology
|November 26, 2003
Summary
Viruses evolve intermediate encapsidation rates due to conflicting selection pressures. This viral evolution strategy balances replication and transmission, impacting virulence and protein production.
Area of Science:
- Evolutionary biology
- Virology
- Theoretical biology
Background:
- Conflicting selection pressures challenge organismal replication robustness.
- Viruses serve as effective models for studying evolutionary conflicts of interest.
Purpose of the Study:
- To develop a multi-level selection model for positive-strand RNA virus life cycles.
- To analyze the interplay between within-cell and between-cell selection dynamics.
- To understand trade-offs in viral life history strategies and their impact on virulence.
Main Methods:
- Constructed a multi-level selection model integrating intracellular replication kinetics and extracellular population dynamics.
- Modeled virion production, transmission, and protein synthesis within a host.
- Analyzed the trade-off between genome replication and genetic translation.
Main Results:
- Viruses evolve towards intermediate, not maximal, encapsidation rates, suggesting selection for intermediate virulence via cellular persistence.
- A theoretical persistence threshold was identified, arising from the trade-off between genome replication and translation.
- Increased genome decay and encapsidation rates paradoxically led to higher virus-encoded protein abundance.
Conclusions:
- Within-host selection levels create trade-offs in viral life history strategies, independent of host mortality.
- Viruses may struggle to resolve conflicting interests across different selection levels, as exemplified by poliovirus data.
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