Figure 2. Effect of PMA on 1,25(OH)2D3-induced recruitment of VDR to chromatin, the CYP24A1 promoter, or the TRPV6 promoter in differentiated Caco-2 cells.
Cells were preincubated with 100 nM PMA or vehicle for 5 min, after which cells were treated for 1 h (panel A) or 2 h (panel B) with 10 nM 1,25(OH)2D3 or vehicle in the absence of PMA. (A) Crude chromatin association assay. VDR was detected in soluble (“S”) and chromatin (“C”) fractions by Western Blot analysis. (B) Quantitative PCR-ChIP analysis for association of VDR with the CYP24A1 and TRPV6 promoters. Bars in panel B represent the mean±sem (n = 3 replicates per treatment). * p < 0.05 versus the vehicle control group; # p < 0.05 versus 1,25(OH)2D3 only group.