Figure 2.

(a) Similarity in gene expression pattern vs. amino acid distance d_a for 124 conserved gene pairs with protein distance 0<d_a<1, third position codon distance 0<d₃<1, and Pearson correlation coefficient of mRNA induction level r > 0.5. Significance of the calculated coefficient of determination r² = 0.03 was determined by a randomization assay. (b) Third position nucleotide distance d₃ vs. protein distance d_a for the 124 genes pairs shown in a. (c) Coefficient of determination r² between protein distances and similarity in expression pattern, calculated for groups of gene pairs with third position distances within a specified range, as shown on the x axis. Numbers of gene pairs in each distance group and P value indicating whether the estimated r² is significantly different from 0 are shown on the x axis as well. P values were determined by a randomization assay.