FIG. 2.
Induction of apoptosis by the overexpression of the core protein in Huh7 cells. (A) A CaspACE fluorometric assay system from Promega Corporation (Madison, WI) was used to measure the activation of caspase-3, which is a hallmark of apoptosis, in Huh7 cells that were transfected with vector only, a classical apoptosis inducer (Bax), the wild-type core protein, and a core protein mutant lacking the putative BH3 domain (coreΔ115-128aa). All experiments were performed in triplicate, and the average values with standard deviations are plotted. (B) Western blot analysis also was performed to determine the cleavage of endogenous PARP, which is a substrate of activated caspase-3, from 116 to 83 kDa (top). Similarly, the expression levels of the different proteins were determined using anti-flag antibody (middle). The amounts of total cell lysates loaded were verified by measuring the levels of endogenous actin (bottom).