Tankyrase1/2 localizes to DSBs.

<p><b>(A)</b> Confocal microscopy pictures of U2OS cells co-transfected with GFP-MDC1 and FN-TNKS1 or MN-TNKS2 after laser-induced DNA damage. Cells were fixed and stained for γ-H2AX, flag or myc using the appropriate antibodies. <b>(B)</b> Confocal microscopy images of U2OS17 cells co-transfected with mCherry-lacR and FN-TNKS1. The cells were also transfected with an ISce-I expressing plasmid in panels e-h. TNKS localizes to pure DSBs as visualized on panels e-h. The quantification of TNKS localization frequency to DSBs is shown on the right, values obtained from three independent experiments are shown with SD (N = 100). <b>(C)</b> Confocal microscopy pictures of U2OS17 cells co-transfected with mCherry-lacR-MDC1 and FN-TNKS1. An ISce-I expressing plasmid was also transfected on panels m-p. Values are calculated as on panel (B). <b>(D)</b> Targeting of FL MDC1 to chromatin leads to DDR activation. U2OS17 cells were transfected with the indicated constructs, and the % of cells harboring γ-H2AX signal on the array was quantified. Results of three independent experiments are shown with SD (N = 100). <b>(E)</b> ATM mediated phosphorylation events do not affect the interaction between TNKS and the BRCTs of MDC1. U2OS17 cells were transfected with the indicated plasmids in the presence or absence of ATMi. Immunofluorescence staining was performed and the % of cells having FN-TNKS1 signal on the array quantified in three independent experiments (N = 100). Average values are shown with SD.