Figure 2.

Mcl-1 is degraded by a proteasome-dependent mechanism after 2 h of mitotic arrest. (A) Loss of Mcl-1 in human cells arrested in mitosis. U2OS and HeLa cells were synchronised in mitotic arrest using the protocol shown. Samples incubated for a total of 2, 4 or 8 h in 250 ng/ml nocodazole were analysed by immunoblotting. (B) Loss of Mcl-1 during mitotic arrest is inhibited by the proteasome inhibitor, MG132. Cells were treated with 10 μM MG132 for 2 h before arrest in mitosis as in (A). Samples were immunoblotted with the antibodies shown.