Center for Reproductive Medicine, Henan Key Laboratory of Reproduction and Genetics, Henan Provincial Obstetrical and Gynecological Diseases (Reproductive Medicine) Clinical Research Center, Henan Engineering Laboratory of Preimplantation Genetic Diagnosis and Screening, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China.
Department of Obstetrics, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China.
J Mol Endocrinol. 2020 Aug;65(2):35-44. doi: 10.1530/JME-20-0053.
A receptive endometrium is required in a successful embryo implantation. The ubiquitination-induced β-catenin degradation is related to the implantation failure.This study aimed to elucidate whether miR-23a-3p regulates endometrial receptivity via the modulation of β-catenin ubiquitination.The expressions of miR-23a-3p and CUL3 were detected in endometrial epithelial cells (EECs) isolated from pregnant mice and in hormone-induced EEC-like Ishikawa cells. The ubiquitination experiment was performed to explore the effect of CUL3 and miR-23a-3p on β-catenin ubiquitination level. The trophoblast attachment was detected by co-culturing JAR (choriocarcinoma cell line) spheroids with Ishikawa cell monolayers. miR-23a-3p was upregulated while CUL3 was downregulated in EECs at day 4 after pregnancy compared with day 1, as well as in hormone-induced Ishikawa cells. miR-23a-3p positively regulated the protein level of β-catenin without affecting the mRNA level. The ubiquitination and degradation of β-catenin was suppressed by miR-23a-3p, while it was promoted by CUL3. Immunoprecipitation confirmed the binding between CUL3 and β-catenin. Luciferase reporter assay confirmed the target relationship between miR-23a-3p and CUL3. The ubiquitination of β-catenin was modulated by the miR-23a-3p/CUL3 pathway. The overexpression of miR-23a-3p promoted JAR spheroid attachments in Ishikawa cells. miR-23a-3p is beneficial for the endometrial receptivity and embryo implantation, whose mechanism is partly through the modulation of CUL3/β-catenin.
成功的胚胎着床需要一个有接受能力的子宫内膜。泛素化诱导的β-连环蛋白降解与着床失败有关。本研究旨在阐明 miR-23a-3p 是否通过调节β-连环蛋白泛素化来调节子宫内膜的接受性。检测了妊娠小鼠子宫内膜上皮细胞（EECs）和激素诱导的 EEC 样 Ishikawa 细胞中 miR-23a-3p 和 CUL3 的表达。进行泛素化实验以探讨 CUL3 和 miR-23a-3p 对β-连环蛋白泛素化水平的影响。通过将 JAR（绒毛膜癌细胞系）球体与 Ishikawa 细胞单层共培养来检测滋养层附着。与妊娠第 1 天相比，妊娠第 4 天的 EEC 中 miR-23a-3p 上调，而 CUL3 下调，激素诱导的 Ishikawa 细胞也是如此。miR-23a-3p 正向调节β-连环蛋白的蛋白水平，而不影响其 mRNA 水平。miR-23a-3p 抑制β-连环蛋白的泛素化和降解，而 CUL3 促进其泛素化和降解。免疫沉淀证实了 CUL3 和 β-连环蛋白之间的结合。荧光素酶报告基因 assay 证实了 miR-23a-3p 和 CUL3 之间的靶关系。miR-23a-3p/CUL3 通路调节了β-连环蛋白的泛素化。miR-23a-3p 的过表达促进了 JAR 球体在 Ishikawa 细胞中的附着。miR-23a-3p 有利于子宫内膜的接受性和胚胎着床，其机制部分是通过调节 CUL3/β-连环蛋白。
