Fig. 3.

Inhibition of CCTα cleavage by caspase 3 knockdown. HEK 293 cells were transfected with siRNAs (150 nM) targeting caspase 3 (A, B), caspase 7 (C), caspases 3 and 7 (C), or a nontargeting (siNT) control for 48 h. Apoptosis was induced with 15 μM chelerythrine for up to 4 h. At the indicated times, cell lysates were prepared, resolved by SDS(8%)-PAGE, and immunoblotted for PARP, caspase 3, caspase 7, CCTα, and actin as described in the Materials and Methods. Symbols indicate full-length (▶) and caspase-cleaved (*) forms of CCTα and PARP. D: Quantification of immunoblots in (B) and (C) showing the percent distribution of holo- and processed CCTα (pro-CCT) in lysates of HEK293 cells transfected with the indicated siRNAs and treated with chelerythrine for 4 h. Results are the mean and standard deviation of three experiments. *P < 0.05 using unpaired t-test compared with siNT.