Variation and selection on codon usage bias across an entire subphylum
Fig 7
Maximum translational selection occurs at an intermediate number of total tRNA genes in the genome.
This plot shows the relationship between the total number of tRNA genes in a genome (tRNAome size) and S-value for each the 327 budding yeast species analyzed in this study. The best fitting model (blue) was a Gaussian distribution with a maximum S-value at 336 tRNA genes. This suggests that species with either low or high numbers of total tRNA genes exhibit lower levels of translational selection.