Wang Xiangguo, Zhu Boyang, Xiong Shanhui, Sheng Xihui, Qi Xiaolong, Huang Qizhen, Chen Chaolei, Guo Yong, Ni Hemin
Animal Science and Technology College, Beijing University of Agriculture, Beijing, China.
Theriogenology. 2018 Mar 1;108:339-347. doi: 10.1016/j.theriogenology.2017.12.030. Epub 2017 Dec 20.
Mucin 1 (MUC1), a cell surface glycoprotein, is expressed mainly in the endometrial luminal epithelium (LE) and glandular epithelium (GE) of the endometrium in many mammalian species including mice, rats, pigs, sheep, horses and humans during various stages of a menstrual or oestrous cycle, where it plays an important role in embryo implantation and placentation. However, the expression and function of MUC1 in uterine tissues during early pregnancy in sheep after artificially-induced oestrous is not known. Therefore, we investigated the expression and function of MUC1 in the early pregnant and non-pregnant uterine tissues of sheep with natural oestrous or artificially-induced oestrous on days 10, 12, 14, 16 and 18 of the cycle by in situ hybridization, quantitative real-time polymerase chain reaction, immunohistochemical staining and western blotting methods. According to our results, MUC1 mRNA and protein expression increased initially but then decreased from days 10-18, peaking on day 14 in the uterine tissues of non-pregnant ewes after both natural and artificially-induced oestrous. MUC1 protein localisation was observed in the LE on days 10, 12 and 14 and in the GE on days 16 and 18. In contrast, MUC1 mRNA and protein expression increased on days 10 and 12, decreased on day 14, but increased again on days 16 and 18 in the uterine tissues of pregnant ewes both in natural oestrous and in artificially-induced oestrous. Additionally, the MUC1 mRNA and protein expression levels in the uterine tissues of the early pregnant sheep were significantly lower than those in the non-pregnant sheep on days 10, 14, and 18, except on day 16(P < 0.01). Enhancing MUC1 protein expression with oestrogen or/and progesterone decreased the blastocyst adhesion rate when blastocysts were co-cultured with endometrial epithelial cells (EECs), while inhibiting MUC1 protein expression with IFN-τ increased the blastocyst adhesion rate when the blastocysts were co-cultured with EECs. Compared with the ewes undergoing natural oestrus, the expression trend and regulation of MUC1 did not change, and the MUC1 expression levels only increased under artificial oestrus conditions. Our data provide important information for improving the conception rate in sheep undergoing artificially-induced oestrus and offer some reference points relating to embryo transfer, oestrus synchronisation and superovulation.
黏蛋白1（MUC1）是一种细胞表面糖蛋白，在包括小鼠、大鼠、猪、绵羊、马和人类在内的许多哺乳动物物种的子宫内膜腔上皮（LE）和腺上皮（GE）中，在月经周期或发情周期的各个阶段均有表达，在胚胎着床和胎盘形成过程中发挥重要作用。然而，人工诱导发情后绵羊妊娠早期子宫组织中MUC1的表达和功能尚不清楚。因此，我们采用原位杂交、定量实时聚合酶链反应、免疫组织化学染色和蛋白质印迹法，研究了在自然发情或人工诱导发情周期的第10、12、14、16和18天，绵羊妊娠早期和未妊娠子宫组织中MUC1的表达和功能。根据我们的研究结果，在自然发情和人工诱导发情后的未妊娠母羊子宫组织中，MUC1 mRNA和蛋白表达最初升高，但在第10 - 18天下降，在第14天达到峰值。在第10、12和14天，MUC1蛋白定位于LE，在第16和18天定位于GE。相比之下，在自然发情和人工诱导发情的妊娠母羊子宫组织中，MUC1 mRNA和蛋白表达在第10和12天升高，在第14天下降，但在第16和18天再次升高。此外，除第16天外，在第10、14和18天，妊娠早期绵羊子宫组织中MUC1 mRNA和蛋白表达水平显著低于未妊娠绵羊（P < 0.01）。当囊胚与子宫内膜上皮细胞（EECs）共培养时，用雌激素或/和孕酮增强MUC1蛋白表达会降低囊胚黏附率，而用IFN-τ抑制MUC1蛋白表达会增加囊胚与EECs共培养时的囊胚黏附率。与自然发情的母羊相比，MUC1的表达趋势和调控没有变化，且MUC1表达水平仅在人工发情条件下升高。我们的数据为提高人工诱导发情母羊的受孕率提供了重要信息，并为胚胎移植、发情同步化和超数排卵提供了一些参考点。
