Figure 4. Effects of CMP1 deletion, CRZ1 deletion or expression of CaMCA1 on H₂O₂-induced apoptosis and caspase activity.

The wild-type (CAI4-EXP), cmp1Δ-EXP, crz1Δ-EXP, cmp1Δ-CMP1, crz1Δ-CRZ1 camca1Δ, CAI4-CaMCA1, cmp1Δ-CaMCA1 and crz1Δ-CaMCA1 cells were exposed to 2 mM H₂O₂ for 3 hours. In another experiment, the wild-type cells were exposed to 2 mM H₂O₂ for 3 hours in the presence of cyclosporin A (0.08 µM). (A) Percentage of cells that were classified as apoptotic by TUNEL assay was shown. (B) The caspase activity was determined by staining the cells with D₂R. (C) Transcription level of CaMCA1 in response to 2 mM H₂O₂ for 3 hours was determined by real time RT-PCR. The mRNA levels were normalized on the basis of their ACT1 levels. Gene expression is indicated as the fold increase of the mutant and CaMCA1-introduced cells relative to that of the wild-type cells. The data are mean values ± S.D. from three independent experiments. * indicates P<0.01 compared with values of CAI4-EXP treated with H₂O₂ only. ** indicates P<0.01 compared with values of parental cells without CaMCA1.