Extended Data Fig. 9: Telomere fusion is required for autophagy activation.
From: Autophagic cell death restricts chromosomal instability during replicative crisis
a, Immunoblotting of growing IMR90E6E7 cells (PD30) upon siRNA targeting DNAPKcs or ligase IV 48 h post-transfection (experiment in Fig. 4b). γTubulin loading control. Two independent experiments were performed. b, Experimental timeline for c–g. c, Metaphase chromosomes of growing IMR90E6E7 cells (PD55) upon shRNA targeting of TRF2 and siRNA targeting of ligase IV at day 6 post-transduction. Left, DAPI staining in blue, telomeres in green and centromeres in red. Arrowheads indicate chromosome fusion events. Two independent experiments were performed. d, Scatter plot showing the number of telomeric γH2AX foci per metaphase. Centre line, mean; error bars, ± s.d. n shows number of metaphases analysed. Two experiments were performed. One-way ANOVA, ns: not significant, ∗∗∗P < 0.001. e, Scatter plots showing the number of fused chromosomes per metaphase, as in d. f, Grouped stacked bars showing the percentage of IMR90E6E7 cells with nucleoplasmic bridges, micronuclei and cytoplasmic chromatin fragments upon shRNA targeting TRF2 and siRNA targeting ligase IV. Bars represent mean ± s.d. n shows number of cells analysed. Three experiments were performed. g, Immunoblotting of IMR90E6E7 cells upon shRNA targeting TRF2 and siRNA targeting ligase IV with γtubulin as loading control. One experiment was performed. h, Scatter plot showing the number of fused chromosomes per metaphase 48 h after induction of wild-type TRF1–FokI, as in d. For gel source data, see Supplementary Fig. 1.
