RIBONUCLEASE P: Unity and Diversity in a tRNA Processing Ribozyme
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چکیده
منابع مشابه
Ribonuclease P: the diversity of a ubiquitous RNA processing enzyme.
Ribonuclease P is the endonuclease required for generating the mature tRNA 5'-end. The ribonucleoprotein character of this enzyme has now been proven in most organisms and organelles. Exceptions, however, are still the chloroplasts, plant nuclei and animal mitochondria where no associated RNAs have been detected to date. In contrast to the known RNA subunits, which are fairly well-conserved in ...
متن کاملChloroplast ribonuclease P does not utilize the ribozyme-type pre-tRNA cleavage mechanism.
The transfer RNA 5' maturation enzyme RNase P has been characterized in Bacteria, Archaea, and Eukarya. The purified enzyme from all three kingdoms is a ribonucleoprotein containing an essential RNA subunit; indeed, the RNA subunit of bacterial RNase P RNA is the sole catalytic component. In contrast, the RNase P activity isolated from spinach chloroplasts lacks an RNA component and appears to ...
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The protein component of ribonuclease P (RNase P) binds to the RNA subunit, forming a functional ribonucleoprotein complex in vivo and enhancing the affinity of the precursor tRNA (pre-tRNA) substrate. Photocrosslinking experiments with pre-tRNA bound to RNase P reconstituted with the protein component of Bacillus subtilis ribonuclease P (P protein) site specifically modified with a crosslinkin...
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Transfer RNA is an essential molecule for biologlcal system, and each tRNA molecule commonly has a c]overleaf structure. Previously, we experimentally showed that some Drosophila tRNA (tRNAAia, tRNAHis, artd tRNAMet) molecules fit to form another, non-cloyerleaf, strllcture in which the 3'-half of the tRNA molecules forms an atternatiye hairpin, and that the tRNA molecules are internally cleaye...
متن کاملRibonuclease P (RNase P) RNA is converted to a Cd(2+)-ribozyme by a single Rp-phosphorothioate modification in the precursor tRNA at the RNase P cleavage site.
To study the cleavage mechanism of bacterial Nase P RNA, we have synthesized precursor tRNA substrates carrying a single Rp- or Sp-phosphorothioate modification at the RNase P cleavage site. Both the Sp- and the Rp-diastereomer reduced the rate of processing by Escherichia coli RNase P RNA at least 1000-fold under conditions where the chemical step is rate-limiting. The Rp-modification had no e...
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ژورنال
عنوان ژورنال: Annual Review of Biochemistry
سال: 1998
ISSN: 0066-4154,1545-4509
DOI: 10.1146/annurev.biochem.67.1.153