Figure 6.

CUG Codon Position Conservation across Yeasts

The proportion of CUG codon positions in the concatenated cytoskeletal and motor protein sequence alignment shared between each two species or species groups. Proportions are calculated in relation to the number of CUG positions in the species or group with fewer CUG positions. Boxes on the diagonal represent the number of distinct CUG positions per species or species group. Given that CUG positions are present every 3.6^th alignment position on average, there is remarkable clustering of the DM clade species and of species with CUG translated as leucine. In contrast, the Ascoidea yeasts share CUG positions only at background level, the level they share CUG positions with other yeasts. Notably, P. tannophilus and N. peltata do not share more CUG codon positions with each other than with any other yeast. This is consistent with their divergent ${\text{tRNA}}_{\text{CAG}}^{\text{Ala}}$, suggesting independent capture of the CUG codon. See also Figure S7.