Skip to main content
. Author manuscript; available in PMC: 2013 Dec 6.
Published in final edited form as: Cell. 2013 May 30;153(6):1266–1280. doi: 10.1016/j.cell.2013.05.023

Figure 6. Recruitment of PTIP to DSBs is ATM and phospho-53BP1 dependent but RIF1-independent.

Figure 6

(A) WT, 53BP1−/− and ATM−/− MEFs were infected with a FLAG-tagged WT PTIP retrovirus. Cells were irradiated with 10 Gy, and FLAG (red) IRIF together with γ-H2AX (green) were assessed four hours post-IR. DAPI is indicated in blue. (B) WT, 53BP1−/−, ATM−/− and 53BP1−/− MEFs reconstituted with 53BP128A were treated with Hoecsht 33342 and then irradiated with a 364 nm laser line. Cells were allowed to recover for 15 minutes before processing for immunfluorescence analysis of PTIP and γ-H2AX. Hoechst counterstain is indicated in blue. (C) Cells expressing GFP-PTIP were irradiated with 10 Gy, and PTIPGFP (green) and RIF1 (red) IRIF were assessed four hours later. Representative image is shown. 82% of PTIP IRIF colocalized with RIF1 foci and 78% of RIF1 colocalized with PTIP foci (n≥800 foci examined. Cells had on average 28 foci). (D) RIF1 IRIF (red) in irradiated WT and PTIP−/− MEFs. (E) RIF1 (red) and PTIP (red) recruitment to laser scissors damage in WT and RIF1−/− MEFs. Damaged cells are indicated by γ-H2AX tracks (green). Scale bars represents 10 μm. See also Figure S10.