Figure 2.

The percentage of complete UTR sequences in the different taxonomic classes that contain (a) introns or (b) upstream AUGs, upstream ORFs or IRES elements. Hum, human; mam, other mammals; rod, rodents; av, Aves; vrt, other vertebrates; lil, Liliopsidae; vir, other plants (Viridiplantae); inv, invertebrates; fun, fungi. Data are taken from UTRdb [47].