The role of NLRP7 and related genes in hydatidiform moles and reproductive failur

NLRP7及相关基因在葡萄胎和生殖障碍中的作用

基本信息

批准号：
7647079
负责人：
IGNATIA B VAN DEN VEYVER
金额：
$ 19.19万
依托单位：
BAYLOR COLLEGE OF MEDICINE
依托单位国家：
美国
项目类别：
财政年份：
2008
资助国家：
美国
起止时间：
2008-06-24 至 2011-05-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/7647079
关键词：
19q13.42 Address Affect Affinity Chromatography Apoptosis Biological Assay Candidate Disease Gene Cell Culture System Chromatin Chromosomes Chromosomes, Human, Pair 13 Complete Hydatidiform Moles Complex Conceptions CpG Islands Cultured Cells DNA DNA Methylation Data Defect Discipline of obstetrics Disease Family Female Fetus Funding Mechanisms Gene Silencing Genes Genetic Materials Genome Genomic Imprinting Goals Growth Human Hydatidiform Mole Hyperplasia Immune Immune response Inherited Karyotype Length Leucine-Rich Repeat Maintenance Methods Methylation Mus Mutate Mutation Natural Immunity Oocytes Oogenesis Organ Pathology Pathway interactions Pattern Placenta Play Pregnancy Pregnancy Complications Pregnancy loss Premature Birth Proteins Recurrence Regulation Reproductive Health Research Risk Rodent Role Secondary to Spontaneous abortion Tissues Woman X Chromosome Yeasts base chromatin immunoprecipitation demethylation genome-wide imprint in vitro Assay insight member natural Blastocyst Implantation new therapeutic target novel overexpression protein function public health relevance reproductive research study trophoblast yeast two hybrid system

项目摘要

DESCRIPTION (provided by applicant): Hydatidiform moles (HM) are abnormally developing pregnancies with hyperproliferative trophoblast and absence of a fetus. The more common sporadic complete hydatidiform moles are 46,XX or 46,XY androgenetic conceptions, in which all the genetic material is paternally derived (AnCHM). Rare recurrent hydatidiform moles are clinically and pathologically identical to AnCHM, but have normal biparental inheritance (BiHM) and their molar trophoblast tissues show abnormal expression of imprinted genes and abnormal methylation of CpG islands at imprinting control regions (ICRs). Recently, autosomal recessive mutations in NLRP7, encoding a protein (NLRP7) with a putative role in innate immunity and apoptosis, were identified in women with recurrent BiHM pregnancies. Prior to this surprising finding, we and others hypothesized that the gene mutated in women with BiHM should be a major regulator of imprinting. However, it is currently not known whether and how NLRP7 might carry out this additional function. Furthermore, it has not yet been studied whether NLRP7 interacts directly with DNA or proteins in chromatin complexes that regulate establishment or maintenance of imprinting marks. Therefore, the overarching hypothesis for this project is that NLRP7 regulates reprogramming and/or maintenance of imprinting marks that are set during human oogenesis by direct interaction with DNA and/or chromatin modifying factors at ICRs. Because NLRP7 has no rodent orthologue, inactivating mutations in mice cannot be generated. Hence, we propose to use in vitro assays and cell culture systems to explore this hypothesis in three specific aims. In specific aim 1 we will investigate by two complementary methods, electromobility shift assays and chromatin immunoprecipitation, whether NLRP7 associates with methylated and unmethylated CpG sequences at ICRs. For specific aim 2 we will perform yeast-two-hybrid interaction studies and co-affinity purification experiments of NLRP7 with candidate proteins that participate in reprogramming and maintenance of imprinting. For Specific aim 3 we will search for novel NLRP7 interactors by a saturated yeast-two-hybrid screen with the full-length NLRP7 protein and the NLRP7-leucine-rich repeat region. For all three specific aims, we will first focus our analysis on known or novel interactors that play a role in imprinting. However, if the data do not support a direct role in imprinting, the experiments, will be able to address an alternate hypothesis, which is that the imprinting defects seen in BiHM are secondary to disruption of a more general role of NLRP7 in immune response within reproductive organs and/or the developing oocyte by focusing on candidate proteins for these pathways. Overall, our goal is to explore new pathways, centered on NLRP7 that are important for imprinting and for reproductive health. Because some women with recurrent BiHM have rare non-molar pregnancies affected by miscarriage, intra-uterine growth retardation or preterm delivery, we predict that this project will uncover candidate genes for these common reproductive disorders, and potentially novel therapeutic targets. PUBLIC HEALTH RELEVANCE: We will investigate a new function of a gene, NLRP7, found to be mutated in women who have rare recurrent hydatidiform moles (a severe pregnancy complication with hyperplastic placenta and absent fetus), and sometimes other pregnancy complications. Because genetic imprinting is abnormal in these hydatidiform moles, we propose to determine whether this gene play a role in the regulation of imprinting. This project has the potential to result in new understanding of genetic imprinting disorders and causes of obstetrics complications and pregnancy loss in general.

描述（由申请人提供）：葡萄胎（HM）是指滋养层过度增殖且无胎儿的异常发育妊娠。更常见的散发性完全葡萄胎是 46,XX 或 46,XY 雄激素受孕，其中所有遗传物质均源自父本 (AnCHM)。罕见的复发性葡萄胎在临床和病理上与AnCHM相同，但具有正常的双亲遗传（BiHM），其磨牙滋养层组织显示印迹基因的异常表达和印迹控制区（ICR）的CpG岛异常甲基化。最近，在反复 BiHM 妊娠的女性中发现了 NLRP7 的常染色体隐性突变，该突变编码一种在先天免疫和细胞凋亡中具有推定作用的蛋白质 (NLRP7)。在这一令人惊讶的发现之前，我们和其他人假设 BiHM 女性中的突变基因应该是印记的主要调节因子。然而，目前尚不清楚 NLRP7 是否以及如何执行这一附加功能。此外，尚未研究NLRP7是否直接与DNA或染色质复合物中的蛋白质相互作用，从而调节印记标记的建立或维持。因此，该项目的总体假设是，NLRP7 通过与 ICR 处的 DNA 和/或染色质修饰因子直接相互作用来调节人类卵子发生过程中设定的印记标记的重编程和/或维持。由于NLRP7没有啮齿动物直系同源物，因此不能在小鼠中产生失活突变。因此，我们建议使用体外测定和细胞培养系统来探索这一假设的三个具体目标。在具体目标 1 中，我们将通过两种互补方法（电动迁移率测定和染色质免疫沉淀）研究 NLRP7 是否与 ICR 上的甲基化和非甲基化 CpG 序列相关。对于具体目标 2，我们将进行酵母-双杂交相互作用研究以及 NLRP7 与参与重编程和印记维持的候选蛋白的共亲和纯化实验。对于具体目标 3，我们将通过饱和酵母双杂交筛选，使用全长 NLRP7 蛋白和富含 NLRP7 亮氨酸的重复区域来寻找新型 NLRP7 相互作用蛋白。对于所有三个具体目标，我们将首先将分析重点放在在印记中发挥作用的已知或新颖的相互作用者上。然而，如果数据不支持印记中的直接作用，实验将能够解决另一个假设，即 BiHM 中看到的印记缺陷是继发于 NLRP7 在免疫反应中更普遍作用的破坏。通过关注这些途径的候选蛋白质来研究生殖器官和/或发育中的卵母细胞。总的来说，我们的目标是探索以 NLRP7 为中心的新途径，这对印记和生殖健康很重要。由于一些患有复发性 BiHM 的女性患有罕见的非葡萄胎妊娠，且受流产、宫内生长迟缓或早产的影响，我们预测该项目将发现这些常见生殖疾病的候选基因，以及潜在的新治疗靶点。公共健康相关性：我们将研究 NLRP7 基因的新功能，该基因在患有罕见复发性葡萄胎（胎盘增生和胎儿缺失的严重妊娠并发症）以及有时还有其他妊娠并发症的女性中发现突变。由于这些葡萄胎的基因印记异常，我们建议确定该基因是否在印记调节中发挥作用。该项目有可能使人们对遗传印记疾病以及产科并发症和流产的原因产生新的认识。