FIGURE 5.

FZ treatment leads to an increased accumulation of ubiquitylated proteins. H460 cells were exposed to increasing concentrations of FZ for 24 h, and cell lysates were made and processed for immunoblotting (A) or the cells were processed for immunofluorescence (B) using anti-ubiquitin antibody (a, control; b, FZ; c, MG132). C, H460 cells were exposed to 1 μm FZ for 48 h or 15 μm MG132 for 12 h, and cell lysates were then prepared and processed for Western blotting using antibody against p53 (DO-1). The blot was overexposed for detection of ubiquitylated p53 bands (top, overexposure; bottom, normal exposure). D, H460 cells were transiently transfected with FLAG-ubiquitin expression plasmid. 24 h later, cells were treated with different doses of FZ. The cell lysates were then processed for immunoblotting using anti-FLAG or anti-ubiquitin antibodies. β-Actin served as an internal control.