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Translational selection frequently overcomes genetic drift in shaping synonymous codon usage patterns in vertebrates
Aoife Doherty1, James O McInerney
1Bioinformatics and Molecular Evolution Unit, Department of Biology, National University of Ireland Maynooth, Maynooth, Co. Kildare, Ireland.
Molecular Biology and Evolution
|July 26, 2013
Summary
Synonymous codon usage in vertebrates is mainly driven by mutation bias. However, translational selection subtly influences codon patterns, indicating its widespread presence across species.
Area of Science:
- Evolutionary Biology
- Genomics
- Molecular Evolution
Background:
- Synonymous codon usage is influenced by mutation, genetic drift, and natural selection.
- Detecting translational selection in vertebrates is difficult due to factors like small population sizes and isochores.
- Previous research suggested natural selection is weak or ineffective in many vertebrate species.
Purpose of the Study:
- To investigate the interplay between mutation, selection, and genetic drift in shaping codon usage in vertebrates.
- To determine the role and prevalence of translational selection in vertebrate synonymous codon usage.
Main Methods:
- Analysis of synonymous codon usage patterns across vertebrate genomes.
- Statistical modeling to disentangle the effects of mutation bias, genetic drift, and translational selection.
Main Results:
- Variation in mutational bias is the primary determinant of codon usage patterns in vertebrates.
- Translational selection acts as a detectable, albeit weak, additional factor influencing synonymous codon usage.
- Evidence suggests translational selection is a common phenomenon across diverse vertebrate species.
Conclusions:
- Translational selection is a widespread evolutionary force in vertebrates, not confined to a few species.
- While mutation bias dominates, translational selection contributes measurably to codon usage patterns.
- This study refines our understanding of the complex evolutionary pressures on codon usage in vertebrates.
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