ESE-3 transcription factor is involved in the expression of death receptor (DR)-5 through putative Ets sites

The death receptor 5 (DR-5), a receptor for tumor necrosis factor-related apoptosis-inducing ligand (TRAIL), is critical for TRAIL-mediated apoptosis in various tumor cells. The ESE-3, a member of Ets transcription factors, regulates the expression of a variety of cellular genes by binding to purine-rich GGAA/T core sequence in cooperation with other transcription factors and co-factors. In this study, we demonstrate for the first time that ESE-3 regulates DR-5 expression through Ets binding sequences on the DR-5 promoter. Using a combination of the electrophoretic mobility shift assay and the luciferase reporter assay, we identified putative Ets sites responsible for ESE-3 transcriptional activity on the DR-5 promoter. In addition, we show the possible involvement of co-factors CBP and p300 in ESE-3-mediated DR-5 up-regulation.