Figure 5. PLK1 interacts with DNA-PKcs in mitotic cells.

(A) DNA-PK immunoprecipitations were carried out from extracts of mitotic cells as in Figure 3. Samples were boiled in SDS–PAGE sample buffer, run on SDS-PAGE gels and probed using the antibodies indicated. (B) PLK1 immunoprecipitations were carried out from asynchronously growing or nocodazole treated cells as described in the Materials and Methods section. Where indicated, cells were treated with the DNA-PK inhibitor (8 μM) or the PLK1 inhibitor (100 nM) for 1 h prior to harvest. The asterisk represents a breakdown product of DNA-PKcs.