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PubMed · 2107327

Doublet preference and gene evolution.

R Hanai·A Wada
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Abstract

Doublet preference analysis was carried out on coding and noncoding regions of Escherichia coli, Saccharomyces cerevisiae, and human mitochondrial and nuclear DNA. The preference pattern in 1-2 and 2-3 doublets in E. coli and S. cerevisiae correlated with that in noncoding regions. The 3-1 doublet preference in E. coli genes with low optimal codon frequency and in S. cerevisiae genes also showed a correlation with each of their noncoding doublet preference. A mechanism to explain these double preference correlations in doublet preference is presented: mutational biases, the origin of the noncoding region doublet preference, evolved so as to maintain the 1-2 and 2-3 doublet preference, which is determined by codon usage. These biases then acted on the 3-1 doublet, which was almost free of coding constraints, resulting in a similar preference in this doublet.

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Base CompositionBiological EvolutionCodonDNA, BacterialDNA, FungalDNA, MitochondrialEscherichia coliHumansRNA, MessengerSaccharomyces cerevisiaeSpecies SpecificityComparative StudyJournal ArticleResearch Support, Non-U.S. Gov't

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R Hanai, A Wada. 1990. Doublet preference and gene evolution.. https://doi.org/10.1007/bf02099937

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