Fig. 4

Active DNA end processing in late micronuclei compartments. a: Detection and quantification of RPA32 phosphorylation (pSerine 33) and ssDNA by specific antibodies in MN compartments of OVCAR-8 cells 36 h after 2-Gy irradiation. Note the nuclear signals have reduced while those in MN were intense. n = 3 biological repeats. Error bars = s.d. **P < 0.01; ***P < 0.005 (t-test). b: Immunostaining and enumeration of phosphorylated NBS1-pSerine 343, BRCA1-pSerine 1524 and TP53-pSerine 15 in MN compartments. **P < 0.01; ***P < 0.005 (t-test). c: Representative images (Upper panel) and quantification of RPA signal in MN compartments (Lower left) or RPA foci in nuclei (lower right) of post-IR OVCAR-8 cells after indicated treatments. Pro-resection genes (MRE11, BRCA1 and WDR70) were knockdown by specific siRNA. Percentage of positive RPA32-pS33 MN population was calculated after 36 h of IR treatment