Evolutionary convergence on highly-conserved 3' intron structures in intron-poor eukaryotes and insights into the ancestral eukaryotic genome.

ABSTRACT: The presence of spliceosomal introns in eukaryotes raises a range of questions about genomic evolution. Along with the fundamental mysteries of introns' initial proliferation and persistence, the evolutionary forces acting on intron sequences remain largely mysterious. Intron number varies across species from a few introns per genome to several introns per gene, and the elements of intron sequences directly implicated in splicing vary from degenerate to strict consensus motifs. We report a 50-species comparative genomic study of intron sequences across most eukaryotic groups. We find two broad and striking patterns. First, we find that some highly intron-poor lineages have undergone evolutionary convergence to strong 3' consensus intron structures. This finding holds for both branch point

SUBMITTER: Irimia M 

PROVIDER: S-EPMC2483917 | biostudies-literature | 2008 Aug

REPOSITORIES: biostudies-literature