Investigation of Eph‐ephrin A1 in the regulation of embryo implantation in sows

Abstract

Eph A1 and ephrin A1 (Eph-ephrin A1) is a key receptor-ligand pair of Eph-ephrin system, which plays important roles in the migration and adhesion of cells, tissue morphogenesis and vasculogenesis in mammals. In order to investigate the regulation of Eph-ephrin A1 during porcine embryo implantation, the expressions of mRNA and protein of Eph-ephrin A1 were detected in different reproductive tissues from twelve sows during embryo implantation period on pregnancy day 13, 18 and 24, respectively. Functions of Eph-ephrin A1 on the migration and adhesion of porcine endometrial epithelial cells were analysed by RNA interference (RNAi), transwell migration assays and MTT assays. Results showed that mRNA levels of Eph-ephrin A1 were highly expressed in endometrial attachment site when compared to other reproductive tissues (p < 0.05) and were peaked on pregnancy day 18 during embryo implantation (p < 0.05). Protein levels of Eph-ephrin A1 were highly expressed in endometrial attachment site and were peaked on pregnancy day 18 (p < 0.05). Eph-ephrin A1 proteins were located in endometrial luminal epithelium, stroma of attachment site and inter-attachment site during embryo implantation, and the protein levels were higher during implantation compared to pre-implantation or post-implantation. Furthermore, silencing ephrin A1 gene significantly reduced the migration and adhesion capacity of porcine endometrial epithelial cells. These findings suggest that the Eph-ephrin A1 protein likely targets endometrial attachment site to enhance the migration and adhesion of porcine endometrial epithelial cells around pregnancy day 18 during pregnancy in sows.

Promoting Roles of Embryonic Signals in Embryo Implantation and Placentation in Cooperation with Endocrine and Immune Systems

“…Considering these findings, we propose that the Eph-ephrin system functions in creating a sufficient period for cross-talk between the embryo and mother, providing embryos with an opportunity to attach to appropriate sites by repeating attachment and detachment in a timely manner ( Figure 2). Consistent with the above suggestion, the Eph-Ephrin A system was also reported to regulate the contact between blastocysts and endometrium during embryo implantation in swine [71,72], and low expression of Eph-ephrin A1 was later demonstrated to be related to an increase in the number of embryos during implantation [73]. During the implantation window, the expression of adhesionpromoting molecules increases, whereas that of adhesion-inhibiting molecules decreases in cooperation with embryonic signals, leading to cell-to-cell interaction between the embryo and endometrial epithelial cells.…”

Effect of miR-143-3p from Extracellular Vesicles of Porcine Uterine Luminal Fluid on Porcine Trophoblast Cells

“…Embryo implantation is an important event in the establishment of pregnancy during mammalian reproduction and significantly affects reproductive traits such as litter weight and size [ 37 ]. ULF-EVs are widely thought to mediate signal communication between the uterus and the blastocyst trophoblast during preimplantation [ 38 ].…”

Ssc-miR-92b-3p Regulates Porcine Trophoblast Cell Proliferation and Migration via the PFKM Gene

“…Embryo implantation is essential to the gestational process and strongly correlates with litter weight and size [28,29]. Successful embryo implantation partially depends on the information exchanged between embryos and the pregnant sow [30].…”