Luciferase expression was measured in the presence or absence of NGFI-A from the unmethylated NR3C1 promoter plasmid compared with a methylated version. There was a significant effect of testing condition on the transcriptional activity of the exon 1F NR3C1 promoter (F = 110.6, P < 0.0001; Fig. 3b). Post hoc analysis revealed that the transcriptional activity of the unmethylated NR3C1 promoter was significantly increased in the presence of the NGFI-A expression vector (NR3C1versus NR3C1 + EGR1; P < 0.0001). Furthermore, methylation of the NR3C1 promoter (the entire NR3C1 construct was methylated in vitro and ligated to an unmethylated vector before transfection, NR3C1-M) reduced basal transcriptional activity of the NR3C1 construct (NR3C1 versus NR3C1-M, P < 0.05). Methylation of the NR3C1 construct also blunted NGFI-A induction of transcription (NR3C1 + EGR1 versus NR3C1-M + EGR1, P < 0.0001).
