Figure 8.

Mechanisms of cytoprotection by mitochondrial survivin. (A) Inhibition of caspase-9 processing. MCF-7 cells transduced with pAd-MTGFP or pAd-MTS were treated with staurosporine and analyzed for caspase-9 processing at the indicated time intervals, by immunoblotting. The position of approximately 37-kDa active caspase-9 is indicated. Lower panel: Quantification of caspase-9 generation by densitometry. (B) XIAP-Smac interaction. Control cultures or MCF-7 cells transduced with pAd-MTS were treated with staurosporine and immunoprecipitated with an antibody to Smac or control IgG, and pellets and supernatants were analyzed by immunoblotting with antibodies to XIAP or Smac.