Fig. 4

Transcription–replication conflicts impair fork progression in MRN-depleted cells. a Regulation of transcription–replication conflicts by RAD50. Proximity ligation assay targeting the replisome (anti-PCNA) and RNA polymerase II (anti-RNA Pol II) is shown with representative images (left) and quantification (right). N = 3; ****P < 0.0001 by t test; mean ± SEM. b Transcription-dependent replisome slowing in RAD50-depleted cells. Cells were treated with 50 μm cordycepin (CORD) for 2 h before IdU labeling. c R-loop-dependent replisome slowing in RAD50-depleted cells. For b and c, an experimental scheme (left), representative DNA fibers from the indicated conditions (middle), and quantified CldU track lengths are shown (right). N = 3; ****P < 0.0001 by t test; mean ± SD. d and e SIRF analysis of Mre11 binding to EdU-labeled nascent DNA during replication stress. PlaB or HU treatment promotes recruitment of Mre11 to forks. This recruitment is R-loop-dependent in PlaB-treated cells. Representative images (d), and quantification (e) are shown. N = 3 for control and PlaB, N = 2 for HU; ****P < 0.0001 by ANOVA; mean ± SD