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PubMed · 1697102

External guide sequences for an RNA enzyme.

A C Forster·S Altman
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Abstract

Ribonuclease P (RNase P) from Escherichia coli or its catalytic RNA subunit can efficiently cleave small RNA substrates that lack the conserved features of natural substrates of RNase P if an additional small RNA is also present. This additional RNA must contain a sequence complementary to the substrate [external guide sequence (EGS)] and a 3'-proximal CCA sequence to ensure cleavage. The aminoacyl acceptor stem and some additional 5'- and 3'-terminal sequences of a precursor transfer RNA are sufficient to allow efficient cleavage by RNAase P, and the 2'-hydroxyl group at the cleavage site is not absolutely necessary for cleavage. In principle, any RNA could be targeted by a custom-designed EGS RNA for specific cleavage by RNase P in vitro or in vivo.

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Base SequenceDeoxyribonucleases, Type II Site-SpecificEndoribonucleasesEscherichia coliEscherichia coli ProteinsMolecular Sequence DataRNARNA PrecursorsRNA, TransferRibonuclease PSubstrate SpecificityJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, Non-P.H.S.Research Support, U.S. Gov't, P.H.S.

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A C Forster, S Altman. 1990-08-17. External guide sequences for an RNA enzyme.. https://doi.org/10.1126/science.1697102

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