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PubMed · 8643369

A conformational switch in a regulated mRNA involves tertiary structure.

T C Gluick·R B Gerstner·D E Draper
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Abstract

The E. coli alpha operon mRNA is autogenously regulated by binding the repressor ribosomal protein S4. Repression occurs via a novel mechanism in which S4 traps the mRNA in a conformation that prevents formation of the complete initiation complex. The conformations have similar stabilities but separated by a high activation energy which is a criterion for a conformational switch. The conformation switch is likely to involve alteration in tertiary structure as indicated by gel electrophoresis and thermal denaturation experiments. It was found that Mg2+ stabilizes the repressed form and tertiary structure, and H+ stabilizes the translated form and have complicated effects on tertiary structure.

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Bacterial ProteinsBase SequenceEscherichia coliKineticsMagnesiumMolecular Sequence DataNucleic Acid ConformationProtonsRNA, MessengerRibosomal ProteinsThermodynamicsJournal ArticleResearch Support, U.S. Gov't, P.H.S.

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T C Gluick, R B Gerstner, D E Draper. 1995. A conformational switch in a regulated mRNA involves tertiary structure.. https://pubmed.ncbi.nlm.nih.gov/8643369/

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