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RNA replication by Q beta replicase: a working model.

D Brown·L Gold
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Abstract

Two classes of RNA ligands that bound to separate, high affinity nucleic acid binding sites on Q beta replicase were previously identified. RNA ligands to the two sites, referred to as site I and site II, were used to investigate the molecular mechanism of RNA replication employed by the four-subunit replicase. Replication inhibition by site I- and site II-specific ligands defined two subsets of replicatable RNAs. When provided with appropriate 3' ends, ligands to either site served as replication templates. UV crosslinking experiments revealed that site I is associated with the S1 subunit, site II with elongation factor Tu, and polymerization with the viral subunit of the holoenzyme. These results provide the framework for a three site model describing template recognition and product strand initiation by Q beta replicase.

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Base SequenceBinding SitesCross-Linking ReagentsKineticsLigandsMacromolecular SubstancesMolecular Sequence DataPeptide Elongation Factor TuQ beta ReplicaseRNARNA-Directed DNA PolymeraseRecombinant ProteinsRepliconTemplates, GeneticUltraviolet RaysUridine TriphosphateVirusesJournal ArticleResearch Support, U.S. Gov't, P.H.S.

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D Brown, L Gold. 1996-10-15. RNA replication by Q beta replicase: a working model.. https://doi.org/10.1073/pnas.93.21.11558

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