SPLICED LEADER RNA SEQUENCES OF TRYPANOSOMA-RANGELI ARE ORGANIZED WITHIN THE 5S RIBOSOMAL-RNA-ENCODING GENES

The spliced leader RNA(SL RNA)-encoding genes of the salivarian New World trypanosome, Trypanosoma rangeli, are organized within the 5S rRNA tandem repeats. Each repeat contains genes encoding an SL RNA and a 5S rRNA in the same orientation of transcription. This SL-5S organization is also present in the African trypanosome, Trypanosoma vivax. A similar association of SL and 5S genes has been observed in some nematodes, but has not been described previously in trypanosomatids.