Luminal epithelial microenvironment in Lpar3(-/-) peri-implantation uterus

描述(申请人提供)：子宫容受性是一种卵巢激素控制的短暂状态，在这种状态下，子宫可以接受胚胎植入。子宫腔内膜上皮(LE)微环境的改变与子宫容受性的建立有关。着床窗期LE微环境失调与子宫容受性缺陷有关。一个基本的知识差距是，在子宫容受性建立后，局部因素是什么以及如何介导卵巢激素信号来改变LE微环境。LPAR3是与子宫容受性有关的溶血磷脂酸(LPA)的第三受体，LPAR3主要在LE中表达，LPAR3缺失会导致LE微环境调控基因在着床前3.5天的表达发生改变。我们的长期目标是了解子宫容受性的分子机制。这项应用的总体目标是识别Lpar3(-/-)子宫中改变的LE微环境和相关候选基因，这是朝着实现我们的长期目标迈出的一步。中心假说是LPAR3是一种局部因子，通过基因表达调节LE微环境。这一假设是根据我们从Lpar3(-/-)小鼠获得的初步数据得出的。其理论基础是，了解LPAR3在LE微环境中的作用将使我们更深入地了解子宫容受性的分子机制。为了实现这一应用程序的目标，将追求两个具体目标。目的1.根据Lpar3基因缺失导致LE微环境不利于着床的工作假设，确定Lpar3(-/-)子宫围着床期LE微环境的改变。目的2.根据Lpar3(-/-)LE微环境改变是Lpar3(-/-)LE基因转录改变引起LE微环境改变的工作假设，确定与Lpar3(-/-)LE微环境改变相关的候选基因的表达。将采用扫描和透射电子显微镜、实时定量聚合酶链式反应、启动子分析、芯片分析和药理学方法。这项拟议的研究意义重大，因为它有望破译局部因子LPAR3如何调节基因表达的分子机制，这些基因可以影响LE微环境，从而影响子宫容受性。所获得的知识将促进和扩大我们对子宫容受性的分子机制的理解。 公共卫生相关性：这项拟议的研究与公共卫生相关，因为子宫容受性缺陷是导致不孕症和早孕丢失的关键因素。该建议旨在了解LPAR3如何调节腔内试验上皮微环境中参与转化的基因的表达，从而影响子宫容受性。对子宫容受性建立的分子机制的了解将为治疗与子宫容受性缺陷相关的不孕症和早孕丢失的药物的发现提供基础。

DESCRIPTION (provided by applicant): Uterine receptivity is an ovarian hormone controlled transient state in which the uterus can accept an embryo to implant. Transformations in luminal endometrial epithelium (LE) mi- croenvironment are associated with the establishment of uterine receptivity. Dysregulated LE microenvironment during implantation window is implicated in defective uterine receptivity. A fundamental knowledge gap is what and how local factors mediate ovarian hormone signals to transform LE microenvironment upon the establishment of uterine receptivity. LPAR3, the third receptor for lysophosphatidic acid (LPA) implicated in uterine receptivity, is mainly ex- pressed in LE and deletion of Lpar3 leads to altered expression of genes involved in regulat-ing LE microenvironment in preimplantation day 3.5 uterus. Our long-term goal is to under- stand the molecular mechanism of uterine receptivity. The overall objective of this application, which is a step toward attaining our long-term goal, is to identify altered LE microenvironment and associated candidate genes in the Lpar3(-/-) uterus. The central hypothesis is that LPAR3 is a local factor regulating LE microenvironment via gene expression. This hypothesis is for- mulated based on our preliminary data obtained from Lpar3(-/-) mice. The rationale is that un- derstanding the role of LPAR3 in LE microenvironment will give us more insight into the mo- lecular mechanism of uterine receptivity. To achieve the goal of this application, two specific aims will be pursed. Aim 1. Identify altered LE microenvironment in peri-implantation Lpar3(-/-) uterus, based on the working hypothesis that deletion of Lpar3 leads to an unfavorable LE microenvironment for implantation. Aim 2. Determine expression of candidate genes asso- ciated with the altered LE microenvironment in peri-implantation Lpar3(-/-) LE, based on the working hypothesis that altered LE microenvironment is caused by altered gene transcription in Lpar3(-/-) LE. Scanning and transmission electron microscopy, realtime PCR, promoter ana- lyses, ChIP assay, and pharmacological approaches will be employed. The proposed re- search is significant because it is expected to decipher the molecular mechanism of how local factor LPAR3 regulates the expression of genes that can influence LE microenvironment thus uterine receptivity. The obtained knowledge will advance and expand our understanding of the molecular mechanism of uterine receptivity. PUBLIC HEALTH RELEVANCE: The proposed research is relevant to public health because defective uterine receptivity is a key factor for infertility and early pregnancy loss. This proposal aims to understand how LPAR3 regulates the expression of genes involved in the transformations of luminal endome- trial epithelium microenvironment to influence uterine receptivity. The understanding of the molecular mechanism in establishment of uterine receptivity will provide a foundation for drug discoveries to treat infertility and early pregnancy loss associated with defective uterine re- ceptivity.