Codon usage divergence of homologous vertebrate genes and codon usage clock

Area of Science:

• Molecular Evolution
• Genomics
• Bioinformatics

Background:

• Synonymous codon usage bias (SCUB) is a significant factor in gene expression and evolution.
• Understanding SCUB patterns across homologous genes provides insights into evolutionary processes.
• Vertebrate genomes offer a rich system for studying evolutionary divergence.

Purpose of the Study:

• To investigate the divergence of synonymous codon usage and its bias in three homologous genes across vertebrate species.
• To establish a correlation between genetic distances derived from codon usage and established taxonomic distances.
• To develop and apply a novel method for quantifying synonymous codon preference bias.

Main Methods:

• Comparative genomics analysis of synonymous codon usage patterns in homologous genes.
• Calculation of genetic distances based on synonymous codon usage divergence.
• Correlation analysis between genetic and taxonomic distances.
• Development of a quantitative method to define synonymous codon preference bias.

Main Results:

• Synonymous codon usage divergence effectively reflects genetic distances among vertebrate species.
• A strong correlation was observed between genetic distances and taxonomic distances.
• A molecular clock phenomenon was identified in alpha-globin and beta-globin gene evolution based on codon usage.
• The developed method revealed significant variations in synonymous codon preference bias across species.

Conclusions:

• Synonymous codon usage divergence serves as a reliable marker for evolutionary relationships in vertebrates.
• Codon usage patterns can be utilized to estimate evolutionary timescales, particularly for globin genes.
• Significant interspecific variation in codon bias highlights its dynamic role in molecular evolution.