Abstract
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 tRNATyr 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.
Original language | English (US) |
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Pages (from-to) | 9193-9197 |
Number of pages | 5 |
Journal | Proceedings of the National Academy of Sciences of the United States of America |
Volume | 88 |
Issue number | 20 |
State | Published - Oct 15 1991 |
Externally published | Yes |
Keywords
- Binding sites for metal ions
- Catalytic RNA
- Metal ion requirement
- Metal ion substitution
ASJC Scopus subject areas
- General