Fig. 2: BLM promotes resection in nucleolar caps.

a RPA32 recruitment to nucleolar caps. U2OS-Cas9 cells were treated with siRNAs for 24 h and subsequently transfected with gRNA plasmids for 6 h, and immunostained with antibody against RPA32. b Quantification of cells with at least one RPA32 cap focus after depletion of resection factors. Cells were treated as in a. The graph depicts mean values +/−SEM. Three biological replicates (two in case of EXO1) (n-values in source data file). For statistical analysis, data was square root transformed and analyzed with one-way Anova. c BRCA1 recruitment to nucleolar caps. Cells were treated as in a and immunostained with antibody against BRCA1. d Quantification of cells treated with gRNA from c. Left panel: quantification of BRCA1 cap foci number per cell (n = 120, 151, 191 cells/condition). Right panel: quantification of BRCA1 cap foci intensity (n = 287, 276, 271 cells/condition). The graphs show one representative experiment. Box limits indicate the central 50% with the horizontal line marking the mean value. Points more than 1.5 times the inter-quartile range outside the box are plotted as outliers (dots), while whiskers cover the remaining points. For statistical analysis a Poisson distribution model was used (left panel) or data were square root transformed (right panel) and analyzed with one-way Anova. e BRCA2 recruitment to nucleolar caps. U2OS-Cas9 cells were treated as in a, and immunostained with antibody against BRCA2. f Quantification of cells with at least one BRCA2 positive cap focus. Cells were treated as in e. The graph depicts mean values +/−SEM (n = 90, 105, 104 (siCon); 88, 102, 101 (siBLM1); 99, 111, 116 (siBLM2) cells/condition/experiment). For statistical analysis, one-way Anova was applied. Scale bars 10 μm. Source data are provided as a Source Data file for panels b, d and f. Three biological replicates unless specifically stated. Statistical significance is depicted with p-values. (EV: empty vector).