BEFV activated the caspase cascade and induced cytochrome c release from mitochondria. (A) Vero cells and (B) MDBK cells were infected with 2 or 5 moi BEFV respectively and incubate then subjected to Western blotting analysis. (C) Cytosol and mitochondria fractionation was performed as described in Materials and Methods Section. Cells were infected with BEFV for the indicated length of time, and equal amounts of cell extracts were subjected to Western blotting analysis.