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Optimization of Synthetic Proteins: Identification of Interpositional Dependencies Indicating Structurally and/or Functionally Linked Residues
Published on: July 14, 2015
Improving evolutionary models for mitochondrial protein data with site-class specific amino acid exchangeability
Katherine A Dunn1, Wenyi Jiang, Christopher Field
1Department of Biology, Dalhousie University, Halifax, Nova Scotia, Canada. kathy.dunn@dal.ca
Plos One
|February 6, 2013
Summary
Mitochondrial protein evolution varies significantly across sites due to unique physiochemical constraints. New models accounting for this site-specific variability improve phylogenetic accuracy in comparative mitogenomics.
Area of Science:
- Evolutionary Biology
- Genomics
- Biochemistry
Background:
- Accurate modeling of mitochondrial sequence evolution is crucial for phylogenomics.
- Current methods often assume uniform evolutionary constraints across all sites, which is biologically unrealistic.
Purpose of the Study:
- To investigate site-specific amino acid evolution in mitochondrial proteins.
- To assess the benefits of modeling this variability for phylogenetic analyses.
Main Methods:
- Developed a novel method to partition sites based on physiochemical properties.
- Applied this method to mammalian and fish mitochondrial genome datasets.
- Used maximum likelihood to estimate site-specific amino acid exchangeability matrices.
Main Results:
- Identified distinct groups of sites with unique physiochemical constraints and differing amino acid exchangeabilities.
- Site-specific matrices significantly improved phylogenetic likelihood estimates.
- Branch length estimates were also notably impacted by the new models.
Conclusions:
- Amino acid evolution is not uniform across mitochondrial protein sites.
- Explicitly modeling site-specific constraints enhances the accuracy of phylogenetic inference.
- Provides new matrices for improved mitogenomic research.
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