The tRNAGlu2 gene in the rrnB operon of E. coli is a prerequisite for correct RNase III processing in vitro.
RNase III cleaves precursor 16S RNA and precursor 23S RNA from the ribosomal RNA transcript. In vitro transcription experiments, using plasmids with the rrnB operon truncated in the 16S RNA and with various deletions in the spacer tRNA region, showed that no matter what size of deletion if the tRNA gene was affected RNase III processing of 16S RNA became incomplete. In comparison to a control plasmid, where only the 16S RNA gene was truncated and that showed normal RNA processing, plasmids where the tRNA gene was deleted partially or totally either the 5' or the 3' end of 16S RNA was processed. This relation between RNase III processing and the 3-dimensional structure of tRNA suggests an interaction between RNase III and a tRNA processing enzyme most probably RNase P.