Mechanisms of Intron Loss and Gain in the Fission Yeast Schizosaccharomyces
Figure 3
Intronization and de-intronization events in fission yeasts.
A) Intronization occurred in the SPBC29A10.02 gene of S. pombe. The intronized region is marked by underlining and variations in splice sites are marked in gray. Alignment of gene SPBC29A10.02 with its related EST is shown below. B) De-intronization occurred in the SPOG_00055 gene of S. cryophilus. Alignment of SPOG_00055 with its orthologs shows a de-intronization event, with the exonized region marked by underlining. Alignment of gene SPOG_00055 with its related EST is shown below. C) The consensus sequence (YTRAY) of branch sites in fission yeasts. Branch site sequences were detected using ICAT [53] and consensus sequences were generated using Weblogo [54]. D) The degraded branch sites of SPOG_00055 compared with its orthologous intron regions. The branch sites predicted by ICAT are marked by underlining and the consensus regions in the branch sites are in bold. Mutations are marked in gray. The introns are shown in lower case while exonic sequences are presented in upper case. Species name abbreviations: S. cryophilus (Scry), S. octosporus (Soct), S. pombe (Spom), and S. japonicus (Sjap).