Figure 3.

The intron density is shown for genes that were transferred at different time scales during evolution from the mitochondrion to the nucleus in Homo sapiens, Drosophila melanogaster, Caenorhabditis elegans and Danio rerio. a) proteins of the oxidative phosphorylation pathway, b) ribosomal mitochondrial proteins. Although the most ancient class of transfers (nad8, nad10, rpl32, rpl19) is unassigned in Figure 2 we consider them to be relatively more ancient than nad11, rps10 and rps3 because the latter are nuclear only in unikonts and the former are nuclear in most eukaryotic groups.