Figure 1.

Cx43 expression enhances apoptosis of HeLa cells. (a) Representative contour plots of untreated and α-Fas (100 ng/ml, 5 h)-treated HeLa-Cx43 cells. The amount of apoptotic cells was determined by annexin V-FITC/PI staining and is displayed in the lower right quadrant (grey). (b) SN- or α-Fas-induced apoptotic cell death of HeLa cells is significantly increased by the expression of Cx43. Apoptosis of HeLa-Cx43 and HeLa-CTL cells untreated or treated with increasing concentrations of SN or α-Fas for 5 h was detected by annexin V-FITC/PI labelling. Mean±S.E.M., *P<0.05 versus untreated (NG); ^#P<0.05 versus CTL cells (NG); n≥8 in at least three different cell cultures. (c) Representative western blots show that apoptotic cleavage of Parp (cl. Parp) and clevage of caspase-7 (cl. Cas) (induced by 10 μM SN and 100 ng/ml α-Fas) is time-dependent and earlier detectable in HeLa-Cx43 cells compared with HeLa-CTL cells