Grant: Master's Award: Canada Graduate Scholarships

Wnt signaling has been shown to significantly contribute to embryo-uterine cross-talk and is essential for successful implantation and pregnancy. In this study, downstream target genes of the Wnt protein signaling pathway were investigated. The transcription factor Gata6 and the prostaglandin 12 synthase, Ptgis, were found to be targets of the Wnt signaling pathway using immunohistochemistry and beta-galactosidase staining. Pseudopregnant mice injected with Wnt7a at post-coital day 4.5 were used in order to ensure that the expression of these genes was indeed activated by the Wnt/beta-catenin signaling pathway. Anti-sense morpholino oligonucleotides with sequences specifically targeting Gata6 and Ptgis were used to knock-down the expression of these two genes during implantation. The absence of these two genes resulted in the failure of the free-floating blastocyst to successfully implant itself into the uterine wall. This research suggests that Wnt protein signaling is a very important component of embryo-uterine cross-talk. The proper activation of the Wnt signaling pathways and its downtream target genes ensures successful implantation and pregnancy.