Transcription Factor Analysis in a Congenital Diaphragmatic Hernia Model

描述(申请人提供)：先天性横隔部缺陷是常见的先天缺陷，发病率和死亡率较高，继发于肺发育不全。尽管这些缺陷具有重大影响，但其发生的分子机制尚不清楚。我们在小鼠基因中发现了一种亚型突变，Fog2，它会导致伴有原发性肺发育不良的横隔膜缺陷，而在一名患有后横隔膜缺陷和肺发育不良的婴儿中，我们发现了一种从头开始的FOG2突变。因此，FOG2基因是第一个涉及非综合征性先天性横隔畸形发病机制的基因，它对肺发育的必要性证实了先天性横隔畸形新生儿也可能有原发肺异常的假说。我们发现，Fog2依赖的大叶发育是由Fog2-Gata4相互作用介导的。Gata4也与小鼠的横隔膜发育有关，并且是人类横隔膜缺陷的候选基因，因为它位于先天性横隔膜疝气(CDH)细胞遗传学热点中。本研究的目的是鉴定Fog2-Gata4介导的肺和横隔膜发育的途径基因和机制。在特定的目标1中，将研究在早期分支肺中与Fog2和Gata4共享表达模式的基因，并将识别在大叶萌发时受Fog2-Gata4相互作用调控的基因。具体目标2将评估视黄酸信号在Fog2和Fog2-Gata4介导的发育中的作用，因为视黄酸在横隔膜和肺发育中都起作用，并且视黄酸受体与Fog2相互作用。在具体目标3中，将确定后部间充质组织是否需要Fog2和Gata4来实现正常发育。由于Fog2和Gata4是人类正常肺和横隔膜发育所必需的，而且这两个基因都是CDH候选基因，本研究将确定控制这一发育的遗传途径，从而更好地了解人类横隔膜缺陷的发病机制。项目简介-先天性横隔膜缺陷是相对常见的出生缺陷，死亡率高，继发于相关的肺发育缺陷的长期发病率。Fog2和Gata4是正常的横隔膜和肺发育所必需的基因。在这项提案中，我们将通过研究Fog2和Gata4介导的横隔膜和肺发育的遗传机制来确定先天性横隔疝的候选基因，这些基因与人类横隔膜和肺缺陷有关。

DESCRIPTION (provided by applicant): Congenital diaphragmatic defects are common birth defects with high morbidity and mortality secondary to associated pulmonary hypoplasia. Despite the significant impact that these defects have, the molecular mechanisms underlying their development are not understood. We identified a hypomorphic mutation in the mouse gene, Fog2 that causes a diaphragmatic defect with primary pulmonary hypoplasia and a de novo FOG2 mutation in a baby with a posterior diaphragmatic defect and pulmonary hypoplasia. FOG2 is thus the first gene implicated in the pathogenesis of non-syndromic congenital diaphragmatic defects, and its necessity for pulmonary development validates the hypothesis that neonates with congenital diaphragmatic defects may also have primary pulmonary abnormalities. We found that Fog2 dependent lobar development is mediated by a Fog2-Gata4 interaction. Gata4 is also implicated in diaphragm development in the mouse, and is a candidate gene for human diaphragmatic defects based on its location in a Congenital Diaphragmatic Hernia (CDH) cytogenetic hot spot. The purpose of this proposal is to identify pathway genes and mechanisms of Fog2-Gata4 mediated lung and diaphragm development. In Specific Aim 1, genes that share expression patterns with Fog2 and Gata4 in the early branching lung will be investigated, and genes will be identified that are modulated by Fog2-Gata4 interactions in the lung at the time of lobar budding. Specific Aim 2 will evaluate the role of retinoic acid signaling in Fog2 and Fog2-Gata4 mediated development, as retinoic acid plays a role in both diaphragm and lung development, and retinoic acid receptors interact with Fog2. In Specific Aim 3, it will be determined whether Fog2 and Gata4 are needed in posterior mesenchymal tissue for normal development. Since Fog2 and Gata4 are required for nomal human lung and diaphragm development and both are CDH candidate genes, this proposal will identify the genetic pathways that control this development leading to a better understanding of the pathogenesis of human diaphragmatic defects. Project Narrative - congenital diaphragmatic defects are relatively common birth defects with high rates of mortality and long term morbidity secondary to associated lung development defects. Fog2 and Gata4 are genes that are necessary for normal diaphragm and lung development. In this proposal, we will identify candidate genes for congenital diaphragmatic hernia by investigating the genetic mechanisms of Fog2 and Gata4 mediated diaphragm and lung development in mouse models that have been associated with human diaphragmatic and lung defects.