Figure 4.

The extent of apparent gene loss in different functional categories of S. cerevisiae genes. Three types of evolutionary events, namely, complete elimination of a gene family, with no detectable S. cerevisiae homolog for a S. pombe protein (Bottom, purple area in each bar), elimination of a paralog (Middle, dark-red area), and anomalous divergence (Top, yellow area) are shown for different functional classes of S. cerevisiae genes. Vertical axis, number of genes. ER, endoplasmic reticulum.