Activation of caspase 3 and cleavage of FLAG–MST3(FL) in myocytes exposed to daunomycin
Myocytes were uninfected or were infected with AdV–FLAG–MST3(FL) or AdV–FLAG–MST3(Δ314–431) (to identify the location of the ‘caspase-cleaved’ form of FLAG-MST3) and (A–C) extracts were prepared. The numbers below the various immunoblot lanes represent relative band absorbances. (A and B) Myocytes were exposed to 0.5 μM daunomycin for the times indicated. Extracts were immunoblotted (IB) with antibodies (Abs) to cleaved (17 kDa) caspase 3 (A), anti-FLAG antibodies (B) or MST3(275–393) (C). (D) Immunocytochemical localization of FLAG–MST3(FL) or FLAG–MST3(Δ314–431) in unstimulated [(Di) and (Dii)] myocytes, and in myocytes exposed to calyculin A [100 nM for 10 min; (Diii)] or daunomycin [0.5 μM for 8 h; (Div)]. Experiments were repeated at least twice with different myocyte preparations with similar results.