Figure 3.

ZNF224 is stabilized by MED28 upon DNA damage. (A-C) Myc-MED28 and/or Flag-ZNF224 co-transfected MCF-7 cells were incubated with 100 µM CPT for the indicated time periods prior to harvesting. Endogenous and exogenous ZNF224 and MED28 were detected using an anti-ZNF224 and anti-MED28 antibodies, respectively; α-tubulin was used as the loading control (n=3, P<0.03 vs. EV control). (D and E) MCF-7 cells were transfected with EV or Myc-MED28. After 24 h, cells were treated with cycloheximide and harvested at the indicated times. Cell extracts were examined by immunoblotting with the indicated antibodies (n=3, P<0.001). MED28, mediator complex subunit 28; ZNF224, zinc finger protein 224; EV, empty vector; CPT, camptothecin; CHX, cycloheximide; Exo, exogenous; Endo, endogenous.