Fig. 2

Role of EZH2-mediated H3K27me3 in the regulation of ADAM12-S expression during syncytialization of human trophoblasts. A HE staining showed the fusion of mononuclear cytotrophoblasts into multinuclear syncytiotrophoblasts with incubation time. Scale bars, 20 μm. B Increased CGB3, GCM1, ERVW-1 and decreased CDH1 mRNA abundance, the syncytialization markers, in cultured trophoblasts upon syncytialization (n = 4). C Decreased EZH2 mRNA (n = 4) and protein (n = 6) abundance during syncytialization. D, E Increased ADAM12S mRNA (n = 4) and protein (n = 5) abundance in trophoblasts and secreted ADAM12-S abundance in the culture medium (n = 5) of trophoblast during syncytialization. F–H siRNA-mediated knockdown of EZH2 expression increased the abundance of ADAM12S mRNA (n = 3) and protein (n = 4) in trophoblasts as well as secreted ADAM12-S protein in the culture medium of trophoblasts (n = 3). Randomly scrambled siRNA served as negative control (NC). Top panels of C–H are representative immunoblots. I Decreased enrichment of EZH2 and H3K27me3 at ADAM12 promoter upon syncytialization of cultured trophoblasts (n = 3). Top panel of I illustrates aligning positions of primers used in the ChIP assay. TSS, transcription start site. Data are means ± SEM. *P < 0.05, **P < 0.01 vs 3 hrs or NC