HEIMER-TORRES, V.R.*; BRAUN, E.L.; KIMBALL, R.T.; University of Florida, Gainesville; University of Florida, Gainesville; University of Florida, Gainesville: Molecular Evolution of Non-Canonical Introns in the Class Aves

Nuclear introns are increasingly being used to understand patterns of vertebrate evolution. Although most introns are classified as canonical, there is a less common non-canonical class of introns that are spliced by an alternative pathway and exhibit characteristic dinucleotide ends. We have examined the phylogenetic utility and patterns of molecular evolution of non-canonical and compared them to canonical introns. We identified four non-canonical intron regions in Gallus gallus (chicken) and designed primers to amplify these regions in approximately twenty-five galliform species (e.g. chicken, turkey, pheasant, etc.). We are now expanding our work by targeting another set of fifteen non-galliform species. Our data show extensive variety in base pair composition as well as in evolutionary rate. Evolutionary patterns within each locus are similar between galliform and non-galliform species. All four non-canonical introns begin with an absolutely conserved 10bp segment, in contrast to the 2bp splice site of canonical introns. Detailed analysis of these non-canonical introns will be presented.