Figure 1.

Differentially expressed genes. (a) Number of differentially expressed (up- and down-regulated) genes by species versus the number of cell doublings. (b) Venn diagram showing the overlap in the sets of differentially expressed genes selected in each species at a false discovery rate of q ≤ 0.1. The number of differentially expressed genes in each region of the Venn diagram is not identical across species, since the number of genes that a species contributes to an orthologous group (that is, number of paralogs) can vary. Ratios in parentheses indicate the number of differentially expressed orthologs by the total number of differentially expressed genes (not all genes possess orthologs).