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Tracking operator state fluctuations in gene expression in single cells.

B Banerjee·S Balasubramanian·G Ananthakrishna·T V Ramakrishnan·G V Shivashankar
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Abstract

We report the results of operator state fluctuations in gene expression for the entire bacterial growth cycle, using single-cell analysis and synthetic unregulated and negative-feedback transcription regulatory gene circuits. In the unregulated circuit, during the cell cycle, we observe a crossover from log-normal-to-normal distribution of expressed proteins and an unusual linear dependence of their standard deviation on the mean gene expression levels. With negative-feedback circuits we find the existence of bimodality as the cell cycle progresses. We suggest that such long-tail and bimodal distributions may be used as selection mechanisms in developmental switches and for assigning cell identity.

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AnisotropyBacteriaBacterial Physiological PhenomenaBiophysicsCell CycleCell DivisionCells, CulturedDNAFlow CytometryGene Expression Regulation, BacterialGenes, RegulatorGenes, ReporterKineticsModels, BiologicalModels, GeneticProtein BindingRecombinant Fusion ProteinsRepressor ProteinsTime FactorsTranscription, GeneticJournal Article

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B Banerjee, S Balasubramanian, G Ananthakrishna, T V Ramakrishnan, G V Shivashankar. 2004. Tracking operator state fluctuations in gene expression in single cells.. https://doi.org/10.1016/s0006-3495(04)74354-4

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