The binding of Class II sRNA MgrR to two different sites on matchmaker protein Hfq enables efficient competition for Hfq and annealing to regulated mRNAs.

ABSTRACT: MgrR is an Hfq-dependent sRNA, whose transcription is controlled by the level of Mg²⁺ ions in Escherichia coli MgrR belongs to Class II sRNAs because its stability in the cell is affected by mutations in Hfq differently than canonical, Class I sRNAs. Here, we examined the effect of mutations in RNA binding sites of Hfq on the kinetics of the annealing of MgrR to two different target mRNAs, eptB and ygdQ, by global data fitting of the reaction kinetics monitored by gel electrophoresis of intermediates and products. The data showed that the mutation on the rim of the Hfq ring trapped MgrR on Hfq preventing the annealing of MgrR to either mRNA. The mutation in the distal face slowed the ternary complex formation and affected the release of MgrR-mRNA complexes f

SUBMITTER: Kwiatkowska J 

PROVIDER: S-EPMC6239178 | biostudies-literature | 2018 Dec

REPOSITORIES: biostudies-literature