Fig. 4.

Protection from apoptosis by chemical chaperones. COS-7 cells were transfected with wild-type CA IV (WT) or R14W CA IV (MT) cDNA and incubated with 10 μM acetazolamide (+AC), 5 mM PBA (+PBA), or normal medium (–AC or –PBA) for 72 h after transfection. (Upper) The cells were fixed and processed for TUNEL staining to assess apoptosis. The percent of cells undergoing apoptosis was calculated from the number of TUNEL-positive cells divided by the number of CA IV-positive cells from three to five fields of each slide. (Lower) The percent TUNEL-positive cells is plotted. These results suggest that induction of apoptosis of COS-7 cells by overexpression of R14W CA IV was inhibited by acetazolamide and PBA.