Figure 3
Relationship between the changes in rate of protein evolution and mRNA expression levels. (a) Histogram showing the distribution of mRNA expression levels (mRNA molecules/cell) for the genes with constant evolutionary rates and the three groups of the genes with evolutionary rate changes. (b) The means of mRNA expression levels with standard errors are shown. Statistically significant differences in mRNA expression level between rate-accelerated and rate-decelerated genes are indicated by an asterisk (*: P < 0.05), when we limited the rate variations to those occurred in the lineages leading to S. cerevisiae after the divergence from S. mikatae.