Figure 3.

Heterodimerization of caspase-1 with caspase-4 or -5 is induced by inflammasome components. (a) MCF-7 cells were transiently transfected with the indicated combinations of C1-Pro (10 ng) and C5-Pro (200 ng) BiFC plasmids along with expression plasmids encoding ASC, NALP1, NALP3 or IPAF. All wells also received dsRed-mito (10 ng) as a reporter for transfection. All cells were treated with qVD-OPH (5 μM) to prevent cell death. At 48 h after transfection, the percentage of transfected cells that were Venus-positive was determined from a minimum of 300 cells per well. Results represent triplicate counts with error bars representing S.D. and are representative of at least three independent experiments. (b) MCF-7 cells were transiently transfected with the indicated combinations of C1-Pro (10 ng) and C4-Pro (20 ng) BiFC plasmids along with expression plasmids encoding ASC, NALP1, NALP3 or IPAF and dsRed-mito (10 ng). Cells were treated and assessed at 48 h as in (a). (c) Representative confocal images of cells from (a) and (b) are shown, with the mitochondria shown in red and caspase BiFC shown in green. Scale bars represent 10 μm