Fig. 6. Codon usage bias in the core and mini-chromosomes of C. destructivum. (a) PCA of codon usage for all amino acids on each chromosome. The region chr1B was considered separately from the rest of chr1. The first two axes accounted for 95 % of the variance. PC, Principal Component. (b) Plots showing codon usage bias for three amino acids (alanine, glutamine and glycine) in genes located on core chromosomes (1 to 10 excluding region 1B), mini-chromosomes 11 and 12 and region 1B. Codon usage on chr11, chr12 and region chr1B differed significantly from that on core chromosomes (Fisher’s exact test, P<0.001) for the ten codons presented except GCG (all comparisons) and GGG (chr12 vs core). Other amino acids are displayed in Fig. S6. The significance is reported for all the codons in the Table S12.
