We sequenced non-ribosomal RNA from a upf1 deletion mutant of S. cerevisiae, and from wild type S. mikatae and S. bayanus, and identified a new class of yeast introns. Overall design: Yeast non-ribosomal RNAs were isolated from vegetatively growing cells or cells treated with rapamycin for 60 minutes to mimick starvation, RNA was sequenced, and splice junctions were identified and validated.