Fig. 5.

The T3-dependent C/EBPα promoter activity was more inhibited by TRα1PV than by TRβ1PV in HepG2 cells stably expressing TRα1. HepG2TRα1 cells were cotransfected with 1 μg of the reporter plasmid (human C/EBPα promoter luciferase), 0.5 μg of RXRβ, and increasing concentrations of expression plasmid for TRα1PV (pcDNA3.1TRαPV) or TRβ1PV (pcDNA3.1TRβPV) as marked. Cells were treated without or with T3 (100 nm) for 24 h. Data were normalized against the protein concentration of the lysates. The percentage of luciferase activity after T3 treatment was calculated and defined as 100%. Assays were performed in triplicate and the data are expressed as mean ± ]scap]sem (n = 6). The data are expressed as bar graph (A) and x-y graph (B). The differences in the transcriptional activity were significant (*, P < 0.05; **, P < 0.01).