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Comparing patterns of natural selection across species using selective signatures
1Program in Computational and Systems Biology, Massachusetts Institute of Technology, Cambridge, Massachusetts, United States of America.
Plos Genetics
|February 13, 2008
Summary
Comparing natural selection across species reveals gene function. Genes with similar evolutionary patterns often share cellular functions, aiding in understanding cellular evolution.
Area of Science:
- Evolutionary biology
- Genomics
- Molecular evolution
Background:
- Comparative genomics offers insights beyond single experiments.
- Understanding natural selection across species is crucial for evolutionary studies.
Purpose of the Study:
- To develop a method for estimating natural selection on genes across species using protein evolutionary rates.
- To identify genes with unusual evolutionary rates and analyze their functional implications.
Main Methods:
- Analyzed protein evolutionary rates across 744 core protein families in 30 gamma-proteobacterial species.
- Corrected for genome-wide factors like mutation rate and demography.
- Defined "selective signatures" based on patterns of fast or slow evolution across species.
Main Results:
- Identified genes evolving unusually rapidly or slowly relative to background rates.
- Demonstrated that correlated selective signatures predict shared cellular functions.
- Observed coordinated evolution of genes within metabolic pathways, such as glycolysis.
Conclusions:
- Selective signatures are predictive of gene function and reveal functional modules within the genome.
- Comparative analysis of natural selection across species enhances understanding of evolutionary pressures on cells.
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