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arXiv · 1007.3447

Inference of plasmid copy number mean and noise from single cell gene expression data

Stéphane Ghozzi·Jérôme Wong Ng·Didier Chatenay·Jérôme Robert
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Abstract

Plasmids are extra-chromosomal DNA molecules which code for their own replication. We previously reported a setup using genes coding for fluorescent proteins of two colors that allowed us, using a simple model, to extract the plasmid copy number noise in a monoclonal population of bacteria [J. Wong Ng et al., Phys. Rev. E, 81, 011909 (2010)]. Here we present a detailed calculation relating this noise to the measured levels of fluorescence, taking into account all sources of fluorescence fluctuations: the fluctuation of gene expression as in the simple model, but also the growth and division of bacteria, the non-uniform distribution of their ages, the random partition of proteins at divisions and the replication and partition of plasmids and chromosome. We show how using the chromosome as a reference helps extracting the plasmid copy number noise in a self-consistent manner.

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Stéphane Ghozzi, Jérôme Wong Ng, Didier Chatenay, Jérôme Robert. 2010-11-16. Inference of plasmid copy number mean and noise from single cell gene expression data. https://doi.org/10.1103/physreve.82.051916

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