Figure 6. Expression of NR4A1 dominant negative mutants inhibits autophagic cell death induced by caspase inhibition.

Mouse fibroblasts L929 were transfected with the indicated expression vectors, and treated or not with the pan-caspase inhibitor zVAD.fmk to induce autophagic cell death. A, cells exposed to zVAD.fmk were rounded up unless they expressed the indicated mutants. Scale bar, 50 µm. B, cell death determined by trypan blue exclusion 24 hr after treatment. There is a reduction of cell death by the expression of either NR4A1 dominant negative mutant ΔDBD or ΔN152, even though the efficiency of transfection was on average 30%. (n = 3; ***, p<0.001).