Ceruloplasmin promoter regulation by CuCl2. (A) Hep3B hepatoma cells were transiently cotransfected with a ceruloplasmin promoter-firefly luciferase reporter gene construct together with a renilla luciferase control reporter gene driven by the SV40 promoter. Transfected cells were treated with the indicated CuCl2 concentrations under normoxic or hypoxic conditions. After 24 hours, firefly luciferase reporter gene activity was determined and divided by the renilla luciferase values to correct for differences in transfection efficiency. Shown are mean relative luciferase activities ± SEM of 2 transfections performed in quadruplicate. (B) Hep3B cells were transfected with HRE wild-type and HRE mutant ceruloplasmin enhancer SV40 promoter constructs, or the SV40 promoter alone, driving firefly luciferase expression. Following 24 hours of 150 μM CuCl2 or 1% oxygen, luciferase induction factors compared with the untreated controls were determined. A representative experiment performed in triplicate is shown as mean values ± SEM.
