Catalytic activity of an RNA molecule prepared by transcription in vitro

Ribonuclease P is a ribonucleoprotein that cleaves precursors to transfer RNA (tRNA) molecules to yield the correct 5′ terminal sequences of the mature tRNA's. The RNA moiety M1 RNA of ribonuclease P from Escherichia coli and the unprocessed transcript prepared in vitro of the gene for M1 RNA can both perform the cleavage reactions ofthe canonical enzyme in the absence ofthe protein moiety. When the transcript ofthe M1 RNA gene is combined with the protein moiety not only is a tRNA precursor cleaved but also the precursor to 4.5S RNA from Escherichia coli.