The acquisition of a spliced leader from an SL RNA is an inter-molecular reaction which precisely joins exons derived from separately transcribed RNAs. Approximately 25% of C. elegans genes are organised into polycistronic transcription units and the presence of SL2 on an mRNA is an indication the gene is in an operon.
The process of obtaining a spliced leader from an SL RNA involves a precise molecular connection between exons derived from separate RNAs. In C. elegans, approximately 25% of genes are grouped into multiple-gene transcription units and the presence of SL2 on an mRNA indicates that gene is part of an operon.