Fig. 5. The cleavage of NuMA, lamins A/C, lamin B, PARP-1 and pro-caspase-8, -3 and -7 during Fas-mediated apoptosis in HeLa cells. Cells grown on a monolayer were treated with Fas antibody and PD 98059 and prepared for SDS-PAGE at different time points as indicated. Identically loaded gels were run and immunoblotted with NuMA, lamin A/C, lamin B, PARP-1, caspase-8, caspase-3 or caspase-7 antibody. Note the gradual cleavage of NuMA and PARP-1 after 8 hours and lamin B after 8-12 hours. Lamins A and C are only partially cleaved during apoptosis. The amounts of procaspase-8, -3 and -7 are diminished and the cleaved 42/44 and 25 kDa fragments of caspase-8 are increased during apoptosis.