Extended Data Fig. 7: Telomere dysfunction activates autophagy.
From: Autophagic cell death restricts chromosomal instability during replicative crisis
a, Box and whisker plots showing the number of telomeric and non-telomeric γH2AX foci per cell upon increasing doses of ionizing radiation (IR), bleocin, or Shield1-based AsiSI, catalytically inactive TRF1–FokI(450A), or wild-type TRF1–FokI 1 h after damage induction. Centre line, median; box limits, first and third quartiles; whiskers, 10th and 90th percentiles. Cells used are post-senescent HMECs (PD23). Two independent experiments were performed. n shows number of cells analysed. One-way ANOVA; ns, not significant, ∗P < 0.05, ∗∗P < 0.01, ∗∗∗P < 0.001. b, Post-senescent HMECs (PD23) were transfected with non-targeting siRNA or siRNA targeting DNAPKcs or ligase IV 48 h before damage induction. Representative confocal images of cells before damage, and 1 h or 48 h post-damage. DAPI staining in blue, telomeres in green and γH2AX in red. Two independent experiments were performed. c, Box and whisker plots showing the number of γH2AX foci per cell at 1, 12, 24 and 48 h after damage induction, as in a. d, Immunoblotting of IMR90E6E7 cells (PD40) at 12, 24 and 48 h post-induction of TRF1–FokI(450A) or wild-type TRF1–FokI. Mock represents non-transduced cells. GAPDH loading control. Two independent experiments were performed. e, LC3-II and P62 turnover assays. Control (non-induced) and wild-type TRF1–FokI-expressing cells were treated with bafilomycin A1 (50 nM for 24 h) or MG132 (10 μM for 24 h). Top, experimental timeline. Bottom, immunoblotting of HMECs and IMR90E6E7 cells before and 48 h after induction of wild-type TRF1–FokI. GAPDH loading control. One experiment was performed. For gel source data, see Supplementary Fig. 1.
