Fig. 9. Effect of irradiation on caspase-12 processing. The cleavage of caspase-12 was analyzed by immunoblotting using a polyclonal antibody. After irradiation with 10 Gy a fragment of approximately 17 kDa became detectable. Bcl-2 overexpression at the ER the mitochondria, or as wild-type Bcl-2 abrogated caspase-12 processing (A). Pretreatment with the caspase-9 inhibitor LEHD-fmk (50 µM) abrogated the processing of caspase-12 as well as the activation of caspase-9 and caspase-3 (B).