Figure 7.
GATAD2B plays an important role in P4-mediated transrepression activity. A–F, effects of siRNA-mediated knockdown of GATAD2B on P4 transrepression activity. hTERT-HM cells stably expressing PR-BWT or PR-AWT were transfected with 20 nm siRNAs targeting GATAD2B or non-targeting siRNA (siNT) control. Data are the mean ± S.E. (error bars) for each treatment group. *, significant (p < 0.05) difference between samples. GATAD2B siRNA transfection markedly reduced endogenous GATAD2B protein expression (G). After transfection, the cells were synchronized in phenol red-free medium supplemented with 1% charcoal-stripped FBS for another 48 h. The cells were then treated with DMSO vehicle (V), IL-1β (10 ng/ml), or IL-1β + P4 (100 nm). Effects of GATAD2B knockdown on COX-2 (A–C) and IL-8 (D–F) mRNA were analyzed after hormonal treatment for 2 h. C and F, repression activity was calculated by comparing the levels of mRNA expression in cells treated with IL-1β alone to mRNA expression after treatment with IL-1β + P4. Effects of siRNA-mediated knockdown of GATAD2B on COX-2 (G) and phospho-p65 at Ser-536 (H) proteins were assayed by immunoblotting after 4 or 2 h of hormonal treatment, respectively. Data are the mean ± S.E. of three replicate determinations for each treatment group. *, significant (p < 0.05) difference between samples.