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Proteins associated with RNase E in a multicomponent ribonucleolytic complex.

A Miczak·V R Kaberdin·C L Wei·S Lin-Chao
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Abstract

The Escherichia coli endoribonuclease RNase E is essential for RNA processing and degradation. Earlier work provided evidence that RNase E exists intracellularly as part of a multicomponent complex and that one of the components of this complex is a 3'-to-5' exoribonuclease, polynucleotide phosphorylase (EC 2.7.7.8). To isolate and identify other components of the RNase E complex, FLAG-epitope-tagged RNase E (FLAG-Rne) fusion protein was purified on a monoclonal antibody-conjugated agarose column. The FLAG-Rne fusion protein, eluted by competition with the synthetic FLAG peptide, was found to be associated with other proteins. N-terminal sequencing of these proteins revealed the presence in the RNase E complex not only of polynucleotide phosphorylase but also of DnaK, RNA helicase, and enolase (EC 4.2.1.11). Another protein associated only with epitope-tagged temperature-sensitive (Rne-3071) mutant RNase E but not with the wild-type enzyme is GroEL. The FLAG-Rne complex has RNase E activity in vivo and in vitro. The relative amount of proteins associated with wild-type and Rne-3071 expressed at an elevated temperature differed.

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Amino Acid SequenceAnimalsBase SequenceChaperonin 60DNA PrimersEndoribonucleasesEpitopesEscherichia coliEscherichia coli ProteinsHSP70 Heat-Shock ProteinsMolecular Sequence DataMyocardiumOligopeptidesPeptidesPhosphopyruvate HydratasePlasmidsPoint MutationPolymerase Chain ReactionPolyribonucleotide NucleotidyltransferaseRNA HelicasesRNA NucleotidyltransferasesRecombinant Fusion ProteinsRestriction MappingSequence Homology, Amino AcidComparative StudyJournal ArticleResearch Support, Non-U.S. Gov't

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A Miczak, V R Kaberdin, C L Wei, S Lin-Chao. 1996-04-30. Proteins associated with RNase E in a multicomponent ribonucleolytic complex.. https://doi.org/10.1073/pnas.93.9.3865

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