WB analysis of MCF cells with DNA damage using GTX00677 MDMX (phospho Ser367) antibody [#15]. MCF cells were preincubated with the proteasome inhibitor MG132 (20 μM) followed by exposed to DNA damaging agents adriamycin (3 μM) or etoposide (20 μM). The cell lysates were used for immunoprecipitation with anti-MdmX antibody and then analyzed by Western blotting.Induction of S367 phosphorylation after DNA damage is associated with increased binding of 14-3-3 to MdmX and accelerated MdmX degradation.