Phylogenetic distribution of intron positions in alpha-amylase genes of bilateria suggests numerous gains and losses.

ABSTRACT: Most eukaryotes have at least some genes interrupted by introns. While it is well accepted that introns were already present at moderate density in the last eukaryote common ancestor, the conspicuous diversity of intron density among genomes suggests a complex evolutionary history, with marked differences between phyla. The question of the rates of intron gains and loss in the course of evolution and factors influencing them remains controversial. We have investigated a single gene family, alpha-amylase, in 55 species covering a variety of animal phyla. Comparison of intron positions across phyla suggests a complex history, with a likely ancestral intronless gene undergoing frequent intron loss and gain, leading to extant intron/exon structures that are highly variable, even among species

SUBMITTER: Da Lage JL 

PROVIDER: S-EPMC3096672 | biostudies-literature | 2011

REPOSITORIES: biostudies-literature