Unproductive splicing of SR genes associated with highly conserved and ultraconserved DNA elements

摘要

The human and mouse genomes share a number of long, perfectly conserved nucleotide sequences, termed ultraconserved elements. Whereas these regions can act as transcriptional enhancers when upstream of genes, those within genes are less well understood. In particular, the function of ultraconserved elements that overlap alternatively spliced exons of genes encoding RNA-binding proteins is unknown. Here we report that in every member of the human SR family of splicing regulators, highly or ultraconserved elements are alternatively spliced, either as alternative 'poison cassette exons' containing early in-frame stop codons, or as alternative introns in the 3' untranslated region.