Transcriptional Regulation: Effects of Promoter Proximal Pausing on Speed, Synchrony and Reliability
Figure 3
(A) Probability distributions for first passage times: Probability density functions of the time to first transcription, obtained by inversion of symbolically calculated Laplace transforms, using rate parameters computed in experimental studies of particular transcription systems. Rates inferred from Darzacq et al. [17] measurements of promoter binding and promoter escape rates (see text). (B) Distribution of total transcripts among a population of simulated cells during 600 minutes of transcription under the ER model with parameters as in (A) and a reinitiation probability of 0.8. (C) as in (B) but for the IR model. (D) Individual cell simulation (see text) showing of the expected results for an mRNA counting assay on the population of cells plotted in (B). Each mRNA transcript is represented by a red dot randomly positioned within the cell. Cells with less than two-thirds of mean mRNA concentration are shaded blue, cells with more than three-halves of mean mRNA concentration are shaded red. (E) as in (D) but for the IR scheme.