Fig. 3. Determination of the mechanism by which ERα regulates circ_0023642 expression.

a Schematic depicting the potential ERα-binding sites in the 5′-region of the UVRAG promoter, the host gene of circ_0023642. b The potential estrogen response elements (EREs) in the promoter region of UVRAG predicted by JASPAR. c The ChIP assay revealed that ERα bound to the 1st potential ERE-binding site in the UVRAG promoter. IgG antibody pull-down was used as a negative control. d Schematic showing the procedure used to clone the 1 kb UVRAG promoter (wild-type or mutant) into the pGL3 basic luciferase reporter vector (pGL3). e Cotransfection of wild-type or mutant ERE UVRAG promoter pGL3-Luciferase constructs into UMUC3 cells with/without oeERα and into J82 cells with/without shERα. The luciferase assay was used to detect promoter activity. *P < 0.05, NS-not significant compared to the controls