ERIC restricts E2F1-mediated apoptosis. U2OS cells stably expressing ER-wild type E2F1 were transfected with either a nonspecific siRNA (siNS) or an siRNA directed against ERIC (si#1 or si#2). Then, cells were left untreated or incubated with OHT (100 nM) for times indicated. A) RNA was extracted and ERIC RNA levels were determined by real-time RT-PCR and normalized to GAPDH levels. One representative experiment is shown out of 3 repeats. B) Cells were analyzed by fluorescence-activated cell sorting (FACS) analysis using propidium-iodide (PI) staining. One representative experiment is shown. Numbers represent percent of cells with a subG1 DNA content. C) Summary of three independent FACS experiments. D) Proteins were extracted from the cells, and western blot analysis performed using antibodies directed against cleaved caspase 3 and actin.