C. Representative images for co-localization between EdU (green) and telomeres (red FISH probe) within PML bodies (cyan) in U2OS and U2OS-hTR cells. White arrows indicate co-localization events. D, E. Quantification of images shown in (C). Co-localization events between EdU foci and APBs were analyzed (D) and the percentage of APBs that are actively engaged in G2/M telomeric synthesis was calculated (E). A total of at least 50 nuclei were scored from three independent experiments. Data information: All scale bars: 5 μm. Data are shown as mean ± SD, with the red line marking the mean value. Statistical analyses were performed with Student's two-tailed unpaired t-test with Welch's correction for normality of distribution. 