Figure 8.

GATAD2B is significantly decreased in human and mouse myometrium during labor. RT-qPCR was used to analyze GATAD2B (A), COX-2 (B), and IL-8 (C) mRNA expression in lower uterine segment myometrium of women in spontaneous labor (IL; n = 12) or not in labor (NIL; n = 20) at term. The Mann–Whitney U test was used to evaluate differences in GATAD2B, IL-8 and COX-2 expression between the NIL versus IL groups. p values are shown for each data set. Immunoblotting was used to analyze GATAD2B (D), COX-2 (E), and IL-6 (F) protein expression in three or more matched series of timed pregnant mouse myometrium between 15.5 dpc and labor (n ≥ 3 mice at each gestational time point). Each immunoblot was analyzed for β-actin as a control for loading and transfer. Scanned immunoblots were quantitated by densitometric analysis followed by correction for loading and transfer variances using ImageJ software. Combined data from scanned immunoblots are shown as bar graphs (arbitrary units (AU)). Data are the mean ± S.E. (error bars) for each group. For one-way analysis of variance, GATAD2B: F(3,12) = 10.57, p = 0.0011; COX-2: F(3,12) = 9.372, p = 0.0018; IL-6: F(3,8) = 8.219, p = 0.0079. Bonferroni's multiple comparison test was carried out post hoc using 15.5 dpc levels for comparison: **, p < 0.01; ***, p < 0.001; n = 4 mice at 15.5 dpc, 3 mice at 17.5 and 18.5 dpc, and 6 mice in labor. G, schematic model of the putative role of GATAD2B in suppression of myometrial contractile gene expression during pregnancy and labor.