Tcf ChIP_Seq analysis in cultured differentiated TSC cells at the presence of DMSO or CHIRGene 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 direct target genes of Ctnnb1 in differentiated TSC cells, differentiated TSC cells at the presence of CHIR are collected and subjected to ChIP-Seq. After aligned to mouse mm10 by HISAT2, peaks are called by MACS2. Our results show that Ctnnb1 the key regulator for placentation by repressing Ascl2 expression as indicated by the presence of significant enrichment of TCF4 at the distal region of Aslc2. This specific enrichment was confirmed by ChIP-qPCR. Additionlly, there are also some other direct genes of Ctnnb1, indicating the essential role of Ctnnb1. This ChIP-Seq data provides fundamental information for our further physiological study of Ctnnb1.