Fig. 2
Tracking single-cell dynamics of lac operon induction. a Dynamics of growth and gene expression in lineages of single cells in an environment that switches between M9+0.2% glucose and M9+0.2% lactose every 4 h. Cell size (black, logarithmic scale) and expression of LacZ-GFP (green, linear scale) are shown as a function of time for a lineage of cells at the bottom of the growth-channel (bottom row) together with first-generation offspring and second-generation offspring cells (second row from the bottom, and top two rows, respectively). The dashed vertical lines show the lineage of cell divisions by connecting each mother cell to its two daughter cells. b Reverse cumulative distributions of lag times to LacZ-GFP induction in single cells at the first (red), second (blue), and third (green) switch from glucose to lactose. c Estimated probability distribution (mean and standard deviation) of single-cell lag times for the first switch in 3-min intervals. The inset shows the correlation in lag times for pairs of cells that had the same mother 1, 2, or 3 generations in the past
