Fig 1: MED25 mediates PEA3-dependent target gene expression. (A) Silencing MED25 down-regulates the induction of MMP-1 mRNA by PEA3 in MCF-7 cells. RNA from cells transfected with control (Ctrl), control and MED25-specific siRNA (Ctrl + si MED25), PEA3 (PEA3) and PEA3 and MED25-specific siRNA (PEA3 + si MED25) was subjected to RT-qPCR. Relative expression levels were calculated using the ΔCt method using expression of GAPDH mRNA as a reference gene. Values are plotted relative to control set to 1. Data represent the mean ± S.E.M. of at least four independent transfections performed in duplicate. (Inset) The knockdown of endogenous MED25 and the expression of Flag-PEA3 were confirmed by western blot. (B) Effect of siRNA-mediated ETVs and MED25 depletion on MMP-1 expression in MDA-MB 231 cells. Data points are the average of three independent experiments. Error bars show standard deviation. (C) Effect of ETVs and MED25 depletion on Mediator occupancy at the MMP-1 promoter. ChIP experiments were performed using antibodies against MED1 and MED18 (ChIP MED) or IgG (ChIP Ctrl). ChIP/Input is average from two biological replicates. Error bars show standard deviation. Statistical significance was determined in paired Student’s t-tests (*P < 0.05).