Expressions of Notch signalling pathway members during early pregnancy in mice

Although pregnancy is initiated and maintained through highly complex mechanisms, it is essential to understand the events that occur before and during early pregnancy to understand a healthy implantation process. The Notch signal, thought to be involved in this process, is frequently the subject of research with its different aspects. To better understand the role of Notch signaling in the peri-implantation period of the mouse uterus, we investigated the state of expression and localization of Notch 3, Notch 4, Rbp-J, Hes1, Hes7, Hey2, HeyL, and Fbw7 in the uterus and implantation sites in early pregnancy. Balb/C mice were divided into groups D1, D4, D5, D6, and D8. For D5 and D6 groups, implantation sites were identified by intravenous injection of Chicago blue. IHC, WB, and QRT-PCR methods were used. Notch 3 was very strong positive on the 4th day of pregnancy. Notch 4 was highly expressed on days 4, 5, 6, and 8 of pregnancy when P₄ levels were high. Hes 1 level was at the lowest on the 4th day of pregnancy. Hes 7 protein expression gradually increased from D1 to D8 in the uteri and implantation sites. Hey 2 expression was at the highest level on the 1st and 4th days. Hey L expression was on the apical of the glands. Fbxw7 that expression was high on the 1st and 4th days of pregnancy. Notch signaling may play an essential role in regulating endometrial receptivity. In addition, our Hes7 results are new to the literature.