Figure 3

RIP1 knockdown shifts TNF-induced TRADD-independent necroptosis to TRADD-dependent apoptosis. (a) Flow cytometric analysis of the percentage of Sytox-positive cells at the indicated time points after TNF stimulation of L929 cells in which RIP1 is knocked down. Knockdown efficiency was determined by western blotting. (b) Western blot analysis of caspase-3 processing at the indicated time points after TNF stimulation of L929 cells in which RIP1 is knocked down. (c) Flow cytometric analysis of the percentage of caspase-3 activity and PI-positive cells at the indicated time points after TNF stimulation of L929pCasper3-BG cells in which RIP1 or RIP1+TRADD are knocked down. Knockdown efficiency of the indicated proteins was determined by western blotting. (d) Cells were stained with Hoechst 33242 (blue) and PI (red) for live-cell imaging and monitored for 8 h. Overlay snapshots of the fluorescent and transmitted light images at the indicated time points after TNF stimulation of L929 cells in which RIP1 is knocked down. Error bars indicate S.Ds of triplicates and data are representative of at least three independent experiments.