Post-synchronization of individual cells within time-lapse series (EAW282).

<p>(A) Time-lapse images of individual cells post-synchronized to the point at which the intensity of UmuC-mKate2 signal reached a maximum (typically 90–150 min after treatment with 100 J/m² UV light). (B) Post-synchronized intensity vs time trajectories for 31 individual cells (of 100 total) that produced a single well-defined burst of UmuC-mKate2 synthesis. The remaining 69 cells either produced no detectable bursts of UmuC-mKate2 synthesis or produced multiple bursts of synthesis, preventing post-synchronization. (C) Mean intensity vs time trajectory over all cells showing three phases in the production of UmuC: (phase I) little UmuC-mKate2 produced; (phase II) increased production of UmuC-mKate2; (phase III) production of UmuC-mKate2 ceases and cellular levels decline. (D) Autocorrelation analysis of post-synchronized time-lapse series showing that the three phases in the production of UmuC correspond with changes in its cellular location: (phase I) weak membrane cross-peaks indicate low levels of membrane-associated UmuC-mKate2; (phase II) stronger membrane cross-peaks indicate production of membrane-associated UmuC-mKate2; (phase III) decreasing membrane cross-peaks and broadening of origin peak indicating redistribution of UmuC-mKate2 to the cytosol. A peak-enhancing filter was applied to fluorescence images prior to autocorrelation analysis [<a href="http://www.plosgenetics.org/article/info:doi/10.1371/journal.pgen.1005482#pgen.1005482.ref057" target="_blank">57</a>].