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Genotyping Single Nucleotide Polymorphisms in the Mitochondrial Genome by Pyrosequencing
Published on: February 10, 2023
Complex mutation and weak selection together determined the codon usage bias in bryophyte mitochondrial genomes.
Bin Wang1, Jing Liu, Liang Jin
1State Key Laboratory of Pharmaceutical Biotechnology, Department of Biology, Nanjing University, Nanjing 210093, China.
Journal of Integrative Plant Biology
|November 26, 2010
Summary
Mutation, not selection, primarily shapes codon usage in bryophyte mitochondrial genomes, with complex mutational dynamics and weak tRNA-mediated selection fine-tuning patterns. This reveals key evolutionary forces in plant mitochondria.
Area of Science:
- Evolutionary Biology
- Genomics
- Molecular Biology
Background:
- Codon usage bias is influenced by mutation and selection.
- The interplay of these forces in green plant mitochondrial genomes remains understudied.
Purpose of the Study:
- To investigate codon usage patterns in bryophyte mitochondrial genomes.
- To identify the primary forces (mutation vs. selection) driving these patterns.
Main Methods:
- Comparative analysis of five bryophyte mitochondrial genomes.
- Utilizing Wright's Nc-GC3s plots for force determination.
- Context-dependent analysis and examination of specific amino acid families (Ser4-Pro-Thr-Val).
Main Results:
- Bryophytes exhibit higher G, C-ending codon usage compared to the alga Chara vulgaris, correlating with higher mitochondrial GC content.
- Mutation pressure is identified as the dominant force shaping codon usage, though complex and context-dependent.
- Transfer RNA (tRNA) genes exert a minor selective pressure on synonymous codon frequencies.
Conclusions:
- Complex mutation and weak selection collectively shape codon usage in bryophyte mitochondrial genomes.
- Mutation is the principal driver, with subtle context-dependent effects.
- tRNA genes play a secondary role in refining codon frequencies.
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