Figure 4.

Expressed Buchnera proteins exhibit a high degree of sequence conservation. Buchnera-LSR1 genes with detected proteins (black) are significantly more conserved than those without detected proteins (grey) (Wilcoxon rank sums, **P<0.001). The degree of sequence conservation is determined as the ratio of nonsynonymous changes per nonsynonymous site (Ka) to synonymous changes per synonymous site (Ks) between orthologous genes of Buchnera-LSR1 and Buchnera-Ak. Ka/Ks ratios for each gene are plotted according to their genome gene order. Pseudogenes are marked with open circles.