Regulation of IGFBP-1 by FKHR and HOXA10 in pregnancy

FKHR 和 HOXA10 在妊娠期间对 IGFBP-1 的调节

• 批准号: 6795223
• 负责人: Ji-Yong Julie Kim
• 金额: $ 28.06万
• 依托单位: NORTHWESTERN UNIVERSITY AT CHICAGO
• 依托单位国家: 美国
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-07-07 至 2007-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6795223
• 关键词: DNA footprinting; baboons; binding proteins; cell differentiation; clinical research; cofactor; decidua; embryo implantation; endometrium; gel mobility shift assay; gene expression; genetic promoter element; human tissue; immunoprecipitation; insulinlike growth factor; nucleic acid probes; nucleic acid sequence; polymerase chain reaction; pregnancy; pregnancy immunology; protein protein interaction; transcription factor; trophoblast

DESCRIPTION (provided by applicant): The long-term objective of this application is to better understand the dynamic interaction that occurs between the conceptus and the mother that allow for the establishment and maintenance of pregnancy. The major focus of our research is on the molecular events that occur in the endometrium in response to early embryonic signals and the invading trophoblast. Aberrant expression of genes in the endometrium during this time is detrimental to the maintenance of pregnancy and could lead to miscarriages, spontaneous abortions and infertility. In response to pregnancy hormones and conceptus factors, the endometrium undergoes a major transformation, termed decidualization. During this process, the stromal cells of the endometrium express important genes. This study focuses on the regulation of a major secretory product of the decidualizing stromal cells, insulin-like growth factor binding protein-1 (IGFBP-1). IGFBP-1 modulates the actions of insulin-like growth factors (IGFs) which are critical during early pregnancy and can act independently of IGFs to regulate trophoblast invasion. Recently, we demonstrated that two transcription factors, FKHR and HOXA10, which have been demonstrated to be important in reproductive processes, interact with one another and up regulate the IGFBP-1 promoter in a cooperative manner in endometrial stromal cells. Based on this novel data, studies have been designed to further delineate the mechanisms involved in the cooperative up regulation of the IGFBP-1 promoter by FKHR and HOXA10. In aim 1 the binding sites of FKHR and HOXA10 on the IGFBP-1 promoter are identified. With the use of a powerful new technique, chromatin immunoprecipitation (CHIP), the binding sites for endogenous FKHR and HOXA10 proteins on the endogenous IGFBP-1 gene within the chromatin in the decidualized stromal cells are determined. This technique allows one to study interaction of transcription factors with the chromatin as they occur in situ. In aim 2, characterization of FKHR and HOXA10 and determination of binding sequences on the IGFBP-1 gene in cells originating from non-pregnant and pregnant baboon endometrium will be performed by taking "snapshots" of the cells and tissue using formaldehyde cross linking. These studies will demonstrate the influence of the conceptus on FKHR and HOXA10 expression and their activation of the IGFBP-1 gene. In aim 3, FKHR and HOXA10 expression and activity in the endometrium of baboons with endometriosis will be studied. The objective of aim 3 is to determine why FKHR and HOXA10 do not significantly activate the IGFBP-1 promoter. The stromal cells from baboons with endometriosis are obviously different from that of a normal animal. These studies will give a better understanding of the molecular events that may be associated with increased implantation failure in women with endometriosis. The three aims in this application will provide valuable insights into the molecular dynamics of the endometrium in response to pregnancy.

描述（由申请人提供）：本申请的长期目标是更好地理解受孕者和母亲之间发生的动态相互作用，从而建立和维持妊娠。我们研究的主要焦点是子宫内膜响应早期胚胎信号和入侵滋养层而发生的分子事件。在此期间子宫内膜中基因的异常表达不利于妊娠的维持，并可能导致流产、自然流产和不孕。为了响应妊娠激素和受孕因素，子宫内膜发生重大转变，称为蜕膜化。在此过程中，子宫内膜的基质细胞表达重要的基因。本研究重点关注蜕膜基质细胞主要分泌产物胰岛素样生长因子结合蛋白-1 (IGFBP-1) 的调节。 IGFBP-1 调节胰岛素样生长因子 (IGF) 的作用，IGF 在妊娠早期至关重要，并且可以独立于 IGF 发挥作用来调节滋养层侵袭。最近，我们证明了两种转录因子 FKHR 和 HOXA10（已被证明在生殖过程中很重要）彼此相互作用，并在子宫内膜基质细胞中以协作方式上调 IGFBP-1 启动子。基于这些新数据，我们设计了研究来进一步阐明 FKHR 和 HOXA10 协同上调 IGFBP-1 启动子所涉及的机制。在目标 1 中，鉴定了 IGFBP-1 启动子上的 FKHR 和 HOXA10 的结合位点。通过使用强大的新技术——染色质免疫沉淀（CHIP），可以确定蜕膜基质细胞染色质内源性 IGFBP-1 基因上内源性 FKHR 和 HOXA10 蛋白的结合位点。这项技术允许人们研究转录因子与染色质原位发生的相互作用。在目标 2 中，将通过使用甲醛交联拍摄细胞和组织的“快照”来表征来自非怀孕和怀孕狒狒子宫内膜的细胞中的 FKHR 和 HOXA10 以及 IGFBP-1 基因上的结合序列。这些研究将证明受孕对 FKHR 和 HOXA10 表达及其对 IGFBP-1 基因激活的影响。在目标 3 中，将研究患有子宫内膜异位症的狒狒子宫内膜中 FKHR 和 HOXA10 的表达和活性。目标 3 的目标是确定为什么 FKHR 和 HOXA10 不会显着激活 IGFBP-1 启动子。患有子宫内膜异位症的狒狒的基质细胞与正常动物明显不同。这些研究将更好地了解可能与子宫内膜异位症女性着床失败增加相关的分子事件。该应用的三个目标将为子宫内膜响应妊娠的分子动力学提供有价值的见解。