Transcription Factor Analysis in a Congenital Diaphragmatic Hernia Model

描述（由申请人提供）：先天性肺发育不全是常见的出生缺陷，继发于相关肺发育不全的发病率和死亡率较高。尽管这些缺陷具有显著的影响，但其发展的分子机制尚不清楚。我们确定了小鼠基因Fog 2中的一种亚型突变，该突变导致了原发性肺发育不全的肺动脉缺陷，并在患有后肺动脉缺陷和肺发育不全的婴儿中发现了新生FOG 2突变。因此，FOG 2是第一个与非综合征性先天性肺发育缺陷的发病机制有关的基因，其对肺发育的必要性验证了先天性肺发育缺陷的新生儿也可能具有原发性肺异常的假设。我们发现，Fog 2依赖的叶发育是由Fog 2-Gata 4相互作用介导的。Gata 4也与小鼠的横膈膜发育有关，并且基于其在先天性横膈膜疝（CDH）细胞遗传学热点中的位置，是人类横膈膜缺陷的候选基因。本研究的目的是鉴定Fog 2-Gata 4介导的肺和膈肌发育的途径基因和机制。在特定目标1中，将研究与早期分支肺中的Fog 2和Gata 4共享表达模式的基因，并将鉴定在肺叶出芽时肺中受Fog 2-Gata 4相互作用调节的基因。具体目标2将评估视黄酸信号传导在Fog 2和Fog 2-Gata 4介导的发育中的作用，因为视黄酸在隔膜和肺发育中起作用，并且视黄酸受体与Fog 2相互作用。在具体目标3中，将确定Fog 2和Gata 4是否需要在后间充质组织中用于正常发育。由于Fog 2和Gata 4是正常人类肺和膈肌发育所必需的，并且两者都是CDH候选基因，因此该提议将确定控制这种发育的遗传途径，从而更好地理解人类肺缺陷的发病机制。项目叙述-先天性肺发育缺陷是相对常见的出生缺陷，具有高死亡率和继发于相关肺发育缺陷的长期发病率。Fog 2和Gata 4是正常横膈膜和肺发育所必需的基因。在这项提议中，我们将通过研究与人类肺和肺缺陷相关的小鼠模型中Fog 2和Gata 4介导的膈肌和肺发育的遗传机制来确定先天性膈疝的候选基因。

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.