In vitro Expression of Hormone Regulated Genes: COUP-TFII in CDH

描述（由申请人提供）：先天性腹股沟疝（CDH）是一种危及生命的出生缺陷，是儿科死亡和活动的主要原因。病理异常的特征是腹部内容物（可能包括胃、肝、肠和脾）通过不适当形成的隔膜不适当地突出到胸腔中，这损害了肺的生长和发育。除了腹部内容物突出导致的继发性缺陷外，肺发育本身也可能受到影响，并导致这些患者的CDH表型。虽然该病在350多年前就有描述，但对CDH的病因知之甚少。使用条件无效突变体，其中COUP-TFII在肠系膜中被删除，我们表明，组织特异性无效突变体的COUP-TFII表现Bochdalek CDH，CDH的最常见形式。COUP-TFII是孤儿核受体的一员，在胚胎发育期间对膈和肺形成至关重要的区域中表达。在前肠间充质（包括肝后间充质板（PHMP））中消融COUP-TFII会导致横膈膜畸形和PHMP与体壁的适当附着失败。近年来，通过阵列CGH和Fish分析，在CDH患者中定位了15q26.1-26.2内的一个关键区域。COUP-TFII是位于该关键区域内的四个已知基因之一。连同我们的COUP-TFII条件突变体的结果，遗传分析暗示COUP-TFII作为最常见类型的Bochdalek CDH的最可能的候选基因。为了描述COUP-TFII如何调节横膈膜和肺的发育以及正确的横膈膜形成的扰动如何导致CDH，提出了三个具体目标：1）。分析条件无效小鼠在膈肌发育期间表现出的缺陷; 2）.分析COUP-TFII在肺发育中的作用及其与CDH的关系; CDH患者中COUP-TFII突变的筛查和表征。通过这项拟议的研究，我们希望为横膈膜和肺的形态发生以及这些器官的畸形如何导致这种毁灭性的先天性缺陷提供重要的见解。通过对CDH患者进行COUP-TFII基因突变的筛查，将有助于进一步完善CDH诊断试剂盒的研制和干预治疗的前景。

DESCRIPTION (provided by applicant): Congenital diaphragmatic hernia (CDH), a life-threatening birth defect, is a major cause of pediatric mortality and mobility. The pathological anomalies are characterized by the inappropriate protrusion of the abdominal contents, possibly including the stomach, liver, intestines and spleen, through an improperly formed diaphragm into the thoracic cavity which impairs lung growth and development. In addition to the secondary defect resulting from protrusion of abdominal contents, lung development itself may be also effected and contribute to CDH phenotypes in these patients. Although the disease was described more than 350 years ago, the etiology of CDH is poorly understood. Using a conditional null mutant in which COUP-TFII is deleted in the mesentery, we showed that tissue specific null mutants of COUP-TFII exhibit Bochdalek CDH, the most common form of CDH. COUP-TFII, a member of orphan nuclear receptors, is expressed in regions critical for the formation of the diaphragm and lung during embryonic development. Ablation of COUP-TFII in the foregut mesenchyme, including the post-hepatic mesenchymal plate (PHMP), results in the malformation of the diaphragm and the failure of appropriate attachment of the PHMP to the body wall. Recently a critical region within 15q26.1-26.2 has been mapped by array CGH and Fish analysis to be deleted in CDH patients. COUP-TFII is one of the four known genes resided within this critical region. Together with results of our COUP-TFII conditional mutants, the genetic analysis implicates COUP-TFII as most likely candidate gene for the most common type of Bochdalek CDH. To delineate how COUP-TFII regulates diaphragm and lung development and how perturbation of proper diaphragm formation might result in CDH, three specific aims are proposed: 1). Analysis of the defects exhibited by the conditional null mice during diaphragm development; 2). Analyze the role of COUP-TFII in lung development and its relationship to CDH; 3). Screen and characterize COUP-TFII mutations in CDH patients. With the proposed study, we hope to provide important insights on morphogenesis of the diaphragm and lung and how malformation of these organs leads to such devastating congenital defects. And eventually, by screening CDH patients for the mutations in COUP-TFII, it will certainly improve the translational prospect in setting up a diagnostic kit and devise an intervention for some CDH patients.