Molecular Evolution Between Drosophila melanogaster and D. simulans Reduced Codon Bias, Faster Rates of Amino Acid Substitution, and Larger Proteins in D. melanogaster

摘要: Both natural selection and mutational biases contribute to variation in codon usage bias within Drosophila species. This study addresses the cause of differences between sibling species, melanogaster D. simulans. Under a model mutation-selection-drift, processes species predicts greater base composition neutrally evolving regions than highly biased genes. Variation intensity, however, larger loci. Greater G+C content 34 coding 46 intron sequences simulans suggest that has undergone reduction intensity for bias. Computer simulations at least fivefold N(e)s silent sites this lineage. Other classes molecular change show lineage effects these Rates amino acid substitution are higher 14 genes which outgroup available. Surprisingly, protein sizes compared two A substantial fraction silent, replacement, insertion/deletion mutations may be weakly selected Drosophila.