Gene expression in the placenta of WT and Ctnnb1 overexpression mice

Wnt signaling are essential for the maintenance and differentiation of stem/progenitor cells, including trophoblast stem cells during placental development. Hyper-activation of Wnt signaling has been shown to relate with human trophoblast diseases. However, litter is known about the impact and underlying mechanisms of excessive Wnt signaling during placental trophoblast development. In the present work, we found that Sfrp1,5 double mutant mouse exhibited disturbed trophoblast differentiation in the placental ectoplacental cone (EPC), where the precursors of secondary trophoblast giant cells (TGCs) and trophoblast cells in the spongiotrophoblast layer are located. Employing mouse models expressing a trunked ß-catenin with exon 3 deletion globally and trophoblast-specifically, combining cultured trophoblast stem cells, we found that hyper-activation of canonical Wnt pathway exhausted the trophoblast precursor cells in the EPC, resulting in the overabundance of giant cells at the expense of spongiotrophoblast cells. Further examination uncovered that hyper-activation of canonical Wnt pathway disturbed trophoblast differentiation in the EPC via repressing Mash2 expression. Collectively, our findings demonstrate that appropriate canonical Wnt-ß-catenin pathway is essential for EPC trophoblast differentiation during placental development. Our work also has high clinical relevance, since abnormal Wnt signaling are often associated with trophoblast-related diseases. Overall design: To detect the gene profiles in WT and Ctnnb1 over expression placentas, placenta are collected and subjected to RNA-Seq. After aligned to mouse mm10 by HISAT2, RPKM value was calculated by Edger. Our results show that Ctnnb1 the key regulator for placentation by repressing Ascl2 expression. The expression of Ascl2 was further confirmed by qPCR and ChIP-qPCR. In lieu of Ctnnb1, there are also some other genes differentially expressed after Ctnnb1 overexpression, indicating the essential role of Ctnnb1. This RNA-Seq data provides fundamental information for our further physiological study of Ctnnb1. Total RNAs in whole placenta from two independent mouse were extracted by TRIzol and purified by ploy-A before subjected to RNA-Seq by HiSeq2500. The expression of level of each gene is normalized to RPKM.