Fig. 4: Pause times and the fraction of transit through EcoRI Q111 roadblocks under conditions of opposing (red) or assisting (blue) force and with (triangles) or without (circles) GreA.

A Transit through EcoRI Q111 roadblocks was rare in 50 mM [K+] but increased dramatically in 150 mM [K+] especially upon the addition of GreA. B Without GreA most ECs in 50 mM [K+] buffer paused indefinitely at EcoRI roadblocks (blue), but adding GreA (red, ~1100 s) rescued paused ECs that resumed transcription (red, ~1300 s). C The CCDFs and (D) characteristic times of all recorded pauses at EcoRI Q111 roadblocks show that the longest pauses were associated with assisting force with and without GreA or opposing force without GreA, and shorter pauses with opposing force plus GreA. Note that all distributions except that for opposing force plus GreA include a significant fraction of indefinitely paused ECs. E The CCDFs and (F) characteristic times of pauses including only ECs that eventually pass through EcoRI Q111 roadblocks in 150 mM [K+] are shown. In (C) and (E), N represents the number of tethered templates that exhibited a transcription event examined under different force and GreA conditions. Data in (D) and (F) represent the exponentially fitted characteristic times ± the 90% confidence intervals (Supplementary Fig. 7).