Figure 2
From: U12 type introns were lost at multiple occasions during evolution
Schematic phylogenetic tree showing instances where U12 introns were lost. Presence or absence of U12 snRNAs and U12 introns are shown as well as paths where U12 splicing seem to have been lost (dashed lines). Figure is based on previous information regarding the phylogenetic distribution of U12 snRNAs [7, 8] as well as results regarding U12 intron distribution described here.