Site-specific cleavage by metal ion cofactors and inhibitors of M1 RNA, the catalytic subunit of RNase P from Escherichia coli.
The location of phosphate residues involved in specific centers for binding of metal ions in M1 RNA, the catalytic RNA subunit of RNase P from Escherichia coli, was determined by analysis of induction of cleavage of RNA by metal ions. At pH 9.5, Mg2+ catalyzes cleavage of M1 RNA at five principal sites. Under certain conditions, Mn2+ and Ca2+ can each replace Mg2+ as the cofactor in the processing of precursor tRNAs by M1 RNA and P RNA, the RNA subunit of RNase P from Bacillus subtilis. These cations, as well as various metal ion inhibitors of the catalytic activity of M1 RNA, also promote cleavage of M1 RNA in a specific manner. Certain conditions that affect the catalytic activity of M1 RNA also alter the rate of metal ion-induced cleavage at the various sites. From these results and a comparison of cleavage of M1 RNA with that of a deletion mutant of M1 RNA and of P RNA, we have identified two different centers for binding of metal ions in M1 RNA that are important for the processing of the precursor to tRNA(Tyr) from E. coli. There is also a center for the binding of metal ions in the substrate, close to the site of cleavage by M1 RNA.
Kazakov
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Department of Biology, Yale University, New Haven, CT 06511.
Altman
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D001412:Bacillus subtilis / Q000201:enzymology / Q000235:genetics*; D001483:Base Sequence; D002872:Chromosome Deletion; D004722:Endoribonucleases / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D004926:Escherichia coli / Q000201:enzymology / Q000235:genetics*; D029968:Escherichia coli Proteins; D006801:Humans; D007700:Kinetics; D046911:Macromolecular Substances; D008274:Magnesium / Q000494:pharmacology*; D008670:Metals / Q000494:pharmacology*; D008969:Molecular Sequence Data; D009690:Nucleic Acid Conformation; D012329:RNA, Bacterial / Q000378:metabolism*; D016337:RNA, Catalytic / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D043262:Ribonuclease P
D029968:Escherichia coli Proteins; D046911:Macromolecular Substances; D008670:Metals; D012329:RNA, Bacterial; D016337:RNA, Catalytic; D004722:Endoribonucleases; C468368:RPP14 protein, human; D043262:Ribonuclease P; C470865:ribonuclease P, E coli; D008274:Magnesium