Fig. 3.

Endogenous LacZ-encoding mRNAs display diffraction-limited dispersion from sites of transcription in E. coli. a, RNA-FISH of wild-type MG1655 E. coli cells using 48 Cy3-labeled DNA probes complementary to the lacZ mRNA sequence after 20 min of IPTG induction. b, Representative FISH intensity profiles of lacZ mRNA signal in individual MG1655 cells. The red dashed line represents the background fluorescence from non-induced cells. c, Visualization of background fluorescence in non-induced MG1655 cells using conditions as in (a). d, Representative fluorescence intensity profiles of individual non-induced cells. The red dashed line represents background fluorescence from non-induced cells. e, Histogram of FWHM values of lacZ mRNA signals from IPTG-induced cells. f, Co-visualization of a chromosomal tetO₂₅₀ array (inserted into the cynX locus adjacent to the lac operon) and the lacZ mRNA signal in DL2875 E. coli cells.