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

• 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
• 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

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）是一种发育异常的妊娠，滋养层细胞过度增殖，胎儿缺失。更常见的散发性完全性葡萄胎是46，XX或46，XY雄激素发生的受孕，其中所有的遗传物质都来自父系（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）CpG岛的异常甲基化。最近，NLRP 7的常染色体隐性突变，编码一种蛋白质（NLRP 7），在先天免疫和细胞凋亡中具有假定的作用，在反复BiHM妊娠的女性中被鉴定。在这个令人惊讶的发现之前，我们和其他人假设BiHM女性中突变的基因应该是印记的主要调节因子。然而，目前还不知道NLRP 7是否以及如何执行这一额外功能。此外，还没有研究NLRP 7是否直接与染色质复合物中的DNA或蛋白质相互作用，调节印记标记的建立或维持。因此，该项目的总体假设是NLRP 7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在人类卵子发生期间设置的印迹标记的重编程和/或维持。由于NLRP 7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，我们建议使用体外试验和细胞培养系统来探索这一假设在三个特定的目标。在具体的目标1中，我们将通过两种互补的方法，电迁移率变化测定和染色质免疫沉淀，研究NLRP 7是否与ICR处的甲基化和未甲基化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和共亲和纯化实验NLRP 7与候选蛋白，参与重编程和维持印记。对于具体目标3，我们将通过饱和酵母双杂交筛选全长NLRP 7蛋白和NLRP 7富含亮氨酸的重复区来寻找新的NLRP 7相互作用物。对于所有这三个特定的目标，我们将首先集中我们的分析已知的或新的相互作用，发挥作用的印记。然而，如果数据不支持在印记中的直接作用，则实验将能够解决替代假设，即在BiHM中观察到的印记缺陷是继发于NLRP 7在生殖器官和/或发育中的卵母细胞内的免疫应答中的更一般作用的破坏，通过关注这些途径的候选蛋白质。总的来说，我们的目标是探索新的途径，以NLRP 7为中心，这对印迹和生殖健康很重要。由于一些患有复发性BiHM的女性患有罕见的非磨牙妊娠，受到流产，宫内生长迟缓或早产的影响，我们预测该项目将揭示这些常见生殖疾病的候选基因，以及潜在的新治疗靶点。 公共卫生关系：我们将研究一种基因NLRP 7的新功能，该基因在患有罕见的复发性葡萄胎（一种严重的妊娠并发症，胎盘增生，胎儿缺如）的女性中发现突变，有时还存在其他妊娠并发症。由于遗传印迹是异常的，在这些葡萄胎，我们建议，以确定该基因是否发挥作用，在调节印迹。该项目有可能导致对遗传印记疾病以及产科并发症和一般妊娠丢失的原因的新理解。