Fig. 5. Cell death is independent of cdc25C function. A, cycling and nocodazole-treated U-20S cells were treated with phosphatase, and cdc25C mobility was determined by Western blotting. I, interphase cdc25C. M, mitotic cdc25C. B, SAOS-2 and U-20S cells were synchronized in G1, infected at 100 and 30 MOI of dnPLK or control virus, treated with nocodazole, and then harvested 24 h later for Western blotting with cdc25C antibody. C, HMECs harvested after 48 h. D, MCF-7 cells infected with 650 and 300 MOI and harvested after 24 h. Open arrow, mitotic form of cdc25C. Solid arrow, interphase form of cdc25C.