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Real-time RNA profiling within a single bacterium.

Thuc T Le·Sébastien Harlepp·Calin C Guet·Kimberly Dittmar·Thierry Emonet·Tao Pan·Philippe Cluzel
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Abstract

Characterizing the dynamics of specific RNA levels requires real-time RNA profiling in a single cell. We show that the combination of a synthetic modular genetic system with fluorescence correlation spectroscopy allows us to directly measure in real time the activity of any specific promoter in prokaryotes. Using a simple inducible gene expression system, we found that induced RNA levels within a single bacterium of Escherichia coli exhibited a pulsating profile in response to a steady input of inducer. The genetic deletion of an efflux pump system, a key determinant of antibiotic resistance, altered the pulsating transcriptional dynamics and caused overexpression of induced RNA. In contrast with population measurements, real-time RNA profiling permits identifying relationships between genotypes and transcriptional dynamics that are accessible only at the level of the single cell.

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Bacterial ProteinsCell CycleCell ProliferationDose-Response Relationship, DrugDrug Resistance, MultipleEscherichia coliEscherichia coli ProteinsGene Expression Regulation, BacterialGenes, ReporterGenotypeGreen Fluorescent ProteinsModels, StatisticalPlasmidsPromoter Regions, GeneticProtein BindingRNARNA, MessengerRecombinant Fusion ProteinsSpectrometry, FluorescenceSpliceosomesTime FactorsTranscription, GeneticJournal ArticleResearch Support, N.I.H., ExtramuralResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, P.H.S.

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BibTeXRIS

Thuc T Le, Sébastien Harlepp, Calin C Guet, Kimberly Dittmar, Thierry Emonet, Tao Pan, Philippe Cluzel. 2005-06-20. Real-time RNA profiling within a single bacterium.. https://doi.org/10.1073/pnas.0503311102

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