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The causes of protein evolutionary rate variation
1Department of Biology, National University of Ireland, Maynooth, County Kildare, Ireland. james.o.mcinerney@nuim.ie
Trends in Ecology & Evolution
|May 16, 2006
Summary
Protein evolutionary rate in yeast is primarily driven by a single factor related to mRNA expression and protein abundance, challenging the long-held belief that protein function was the main determinant.
Area of Science:
- Molecular Biology
- Evolutionary Biology
- Genetics
Background:
- The rate of protein evolution exhibits over a 1000-fold variation.
- For three decades, protein function was considered the primary determinant of evolutionary rate.
- Previous models did not fully account for the variability in protein evolutionary rates.
Purpose of the Study:
- To identify the key factor influencing the rate of protein evolution in yeast.
- To challenge the established paradigm linking protein evolutionary rate solely to protein function.
- To investigate the role of gene expression and protein abundance in evolutionary dynamics.
Main Methods:
- Analysis of protein abundance data in yeast.
- Examination of mRNA expression levels.
- Assessment of synonymous codon usage patterns.
- Correlation analysis between these factors and protein evolutionary rates.
Main Results:
- A single underlying factor, encompassing mRNA expression, protein abundance, and codon usage, was identified as the chief driver of protein evolutionary rate.
- This factor explained a significant portion of the variability previously attributed to protein function.
- The findings challenge the long-standing hypothesis that protein function is the sole determinant.
Conclusions:
- The study identifies a unifying factor regulating protein evolutionary rates in yeast.
- This finding suggests that gene expression and protein abundance are critical determinants of evolutionary speed.
- Further research is needed to ascertain if this rule applies universally across all biological systems.
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