In vitro analysis of processing at the 3'-end of precursors of M1 RNA, the catalytic subunit of Escherichia coli RNase P: multiple pathways and steps for the processing.
M1 RNA of 377 nucleotides, the catalytic subunit of Escherichia coli RNase P, is produced by a 3' processing reaction from precursor M1 RNA, a major transcript from the rnpB gene. We analyzed products and intermediates generated by the in vitro processing reaction using a 40% ammonium sulfate precipitate of the S30 fraction (ASP-40) and determined their involvement in the processing. From the results we proposed a model of two pathways for 3' processing of M1 RNA. In this model, one pathway (pathway I) involves +385/+386 intermediates and the other pathway (pathway II) does not. The position of the 3'-end of the precursor molecule determined the choice of the pathways. The precursor having the 3'-end of +413 was processed by both pathways while that having the +415 end was processed only by pathway II. The ASP-40 fraction generated processing products (termed +378/+379 RNA) containing one or two more nucleotides at the 3'-end than M1 RNA, regardless of which pathway was used. Therefore, both pathways require the final 3' trimming for complete processing. The endonucleolytic generation of +378/+379 RNA by pathway II was blocked by the rne-3071 mutation, suggesting that this step is carried out by RNase E.
Kim
S
S
Department of Chemistry, Korea Advanced Institute of Science and Technology, Taejon 305-701, Korea.
Sim
S
S
Lee
Y
Y
D020134:Catalytic Domain; D004722:Endoribonucleases / Q000378:metabolism*; D004926:Escherichia coli / Q000201:enzymology*; D029968:Escherichia coli Proteins; D009690:Nucleic Acid Conformation; D012322:RNA Precursors / Q000378:metabolism*; D012323:RNA Processing, Post-Transcriptional; D012329:RNA, Bacterial / Q000378:metabolism*; D016337:RNA, Catalytic / Q000378:metabolism*; D043262:Ribonuclease P
D029968:Escherichia coli Proteins; D012322:RNA Precursors; D012329:RNA, Bacterial; D016337:RNA, Catalytic; D004722:Endoribonucleases; D043262:Ribonuclease P; C470865:ribonuclease P, E coli; C022537:ribonuclease E