Figure 4
From: Evolution of spliceosomal introns following endosymbiotic gene transfer
A comprehensive phylogeny of the gene nad7 including mitochondrial and nuclear encoded homologs. The tree is rooted by alpha-proteobacterial homologs. The two independent gene transfers of nad7 from the mitochondrion to the nucleus are labelled at the tree. The nucleotide region of the shared intron position is shown. The different lengths of the intron sequences are indicated in parentheses, the splicing sites are marked in bold