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Updated: Jul 14, 2026
09:40
Phage Phenomics: Physiological Approaches to Characterize Novel Viral Proteins
Published on: June 11, 2015
Variable epistatic effects between mutations at host recognition sites in phiX174 bacteriophage.
1Department of Biological Sciences, University of Idaho, Moscow, Idaho 83844, USA. kpepin@nmsu.edu
Evolution; International Journal of Organic Evolution
|June 30, 2007
Summary
Epistatic interactions, where gene mutations affect each other, vary significantly with environmental conditions. This study shows that even mutations at the same sites in bacteriophage phiX174 exhibit condition-dependent epistasis, impacting evolutionary processes.
Area of Science:
- Evolutionary biology
- Genetics
- Molecular biology
Background:
- Epistatic interactions between mutations are common but their variability is poorly understood.
- Understanding the causes and extent of epistasis variation is crucial for evolutionary studies.
Purpose of the Study:
- To investigate the variation in epistatic effects of mutations at two host recognition sites in bacteriophage phiX174.
- To determine how environmental conditions influence the sign, degree, and variability of these epistatic effects.
Main Methods:
- Calculated epistatic effects using the sum of fitness effects (log scale) of single and double mutants.
- Examined five mutation combinations across six different environmental conditions.
- Analyzed bacteriophage phiX174, a well-established model system.
Main Results:
- Epistatic effects exhibited significant variation in sign, magnitude, and variability across different conditions.
- Environmental conditions altered the sign and variability of epistasis even for mutations at the same genetic sites.
- The study provides empirical evidence for condition-dependent epistasis.
Conclusions:
- Environmental context is a critical factor influencing epistatic interactions.
- The findings underscore the importance of considering environmental variability when studying the role of epistasis in evolution.
- Further research is needed to fully elucidate the mechanisms driving condition-dependent epistasis.
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