Fig. 4

CSB is recruited to FokI-induced DSBs in S phase to inhibit RIF1. a Quantification of the percentage of synchronized Myc-CSB-expressing U2OS-265 cells exhibiting indicated proteins at FokI-induced DSBs. For Myc-CSB, a total of 250 Myc-CSB-expressing cells were scored for each independent experiment in blind. For RIF1, a total of 500–550 cells were scored in blind for each independent experiment. SDs from three independent experiments are indicated. b Quantification of the percentage of synchronized Myc-CSB-expressing U2OS-265 cells exhibiting γH2AX at FokI-induced DSBs. A total of 500–550 cells were scored in blind for each independent experiment. SDs from three independent experiments are indicated. c Western analysis of U2OS-265 parental (WT) and 53BP1 KO cells. The γ-tubulin blot was used as a loading control here and the following figures. d Quantification of the percentage of U2OS-265 WT and 53BP1 KO cells with γH2AX at FokI-induced DSBs. Scoring was done as in 3b. SDs from three independent experiments are indicated. e Quantification of the percentage of U2OS-265 WT and 53BP1 KO cells with RIF1 at FokI-induced DSBs. Scoring was done as in Fig 3b. SDs from three independent experiments are indicated. f Quantification of the percentage of synchronized Myc-CSB-expressing WT and 53BP1 KO U2OS-265 cells with Myc-CSB at FokI-induced DSBs. A total of 250 Myc-CSB-expressing cells were scored for each independent experiment in blind. SDs from three independent experiments are indicated. *P < 0.05 (Student t test). g Quantification of the percentage of U2OS-265 WT and CSB-KO cells with γH2AX at FokI-induced DSBs. Scoring was done as in Fig. 3b. SDs from three independent experiments are indicated. h Quantification of the percentage of synchronized U2OS-265 WT and CSB KO cells with RIF1 at FokI-induced DSBs. Scoring was done as in Fig. 3b. SDs from three independent experiments are indicated. *P < 0.05 (Student t test). i Quantification of the percentage of synchronized U2OS-265 WT and CSB KO cells with BRCA1 at FokI-induced DSBs. Scoring was done as in Fig. 3b. SDs from three independent experiments are indicated. *P < 0.05 (Student t test). j Western analysis of U2OS-265 WT and CSB KO cells