article published Calin C Guet author 47F8433E-F248-11E8-B48F-1D18A9856A870000-0001-6220-2052 Luke Bruneaux author Taejin Min author Dan Siegal Gaskins author Israel Figueroa author Thierry Emonet author Philippe Cluzel author Fluorescence correlation spectroscopy (FCS) has permitted the characterization of high concentrations of noncoding RNAs in a single living bacterium. Here, we extend the use of FCS to low concentrations of coding RNAs in single living cells. We genetically fuse a red fluorescent protein (RFP) gene and two binding sites for an RNA-binding protein, whose translated product is the RFP protein alone. Using this construct, we determine in single cells both the absolute [mRNA] concentration and the associated [RFP] expressed from an inducible plasmid. We find that the FCS method allows us to reliably monitor in real-time [mRNA] down to similar to 40 nM (i.e. approximately two transcripts per volume of detection). To validate these measurements, we show that [mRNA] is proportional to the associated expression of the RFP protein. This FCS-based technique establishes a framework for minimally invasive measurements of mRNA concentration in individual living bacteria. Oxford University Press2008 eng 0305-1048 1362-4962 1851534710.1093/nar/gkn329 3612 yes C.C. Guet, L. Bruneaux, T. Min, D. Siegal Gaskins, I. Figueroa, T. Emonet, P. Cluzel, Nucleic Acids Research 36 (2008). Guet, Calin C, Luke Bruneaux, Taejin Min, Dan Siegal Gaskins, Israel Figueroa, Thierry Emonet, and Philippe Cluzel. “Minimally Invasive Determination of MRNA Concentration in Single Living Bacteria.” <i>Nucleic Acids Research</i>. Oxford University Press, 2008. <a href="https://doi.org/10.1093/nar/gkn329">https://doi.org/10.1093/nar/gkn329</a>. C. C. Guet <i>et al.</i>, “Minimally invasive determination of mRNA concentration in single living bacteria,” <i>Nucleic Acids Research</i>, vol. 36, no. 12. Oxford University Press, 2008. Guet, C. C., Bruneaux, L., Min, T., Siegal Gaskins, D., Figueroa, I., Emonet, T., &#38; Cluzel, P. (2008). Minimally invasive determination of mRNA concentration in single living bacteria. <i>Nucleic Acids Research</i>. Oxford University Press. <a href="https://doi.org/10.1093/nar/gkn329">https://doi.org/10.1093/nar/gkn329</a> Guet CC, Bruneaux L, Min T, Siegal Gaskins D, Figueroa I, Emonet T, Cluzel P. 2008. Minimally invasive determination of mRNA concentration in single living bacteria. Nucleic Acids Research. 36(12), e73. Guet, Calin C., et al. “Minimally Invasive Determination of MRNA Concentration in Single Living Bacteria.” <i>Nucleic Acids Research</i>, vol. 36, no. 12, e73, Oxford University Press, 2008, doi:<a href="https://doi.org/10.1093/nar/gkn329">10.1093/nar/gkn329</a>. Guet CC, Bruneaux L, Min T, et al. Minimally invasive determination of mRNA concentration in single living bacteria. <i>Nucleic Acids Research</i>. 2008;36(12). doi:<a href="https://doi.org/10.1093/nar/gkn329">10.1093/nar/gkn329</a> 37542018-12-11T12:04:59Z2026-05-29T11:58:14Z