EBF1 negatively regulates ERβ protein levels and downstream activity.

<p>MCF-7/C4–12 cells were transfected with Flag.ERβ in the presence or absence of EBF1 and then treated with E2 or Vehicle control. (A) Flag.ERβ protein and (B) mRNA levels were measured on Western blots and by RT-qPCR, respectively. ERβ transcriptional response was measured in an (C) ERE-Luciferase reporter assay as well as (D) by endogenous target gene regulation. (E) C4–12/Flag.ERβ cells were transfected with EBF1 (or pcDNA3.1(-) as Vector control) and treated with E2 for 3 days. Cell confluency, detected by the Incucyte FLR, was used to measure cell proliferation. The bar graph represents the fold change relative to day 0. Error bars represent standard deviation.