Transcription Factor Analysis in a Congenital Diaphragmatic Hernia Model

描述（由申请人提供）：先天性膈肌缺陷是常见的出生缺陷，其发病率和死亡率很高，继发于相关的肺发育不全。尽管这些缺陷具有重大影响，但其发展背后的分子机制尚不清楚。我们在小鼠基因 Fog2 中发现了一种亚等位性突变，该突变会导致膈肌缺损并伴有原发性肺发育不全，并且在患有后膈缺损和肺发育不全的婴儿中发现了新的 FOG2 突变。因此，FOG2 是第一个与非综合征性先天性膈肌缺陷发病机制有关的基因，其对肺部发育的必要性验证了先天性膈肌缺陷新生儿也可能患有原发性肺部异常的假设。我们发现 Fog2 依赖性脑叶发育是由 Fog2-Gata4 相互作用介导的。 Gata4 还与小鼠膈肌发育有关，并且根据其在先天性膈疝 (CDH) 细胞遗传学热点中的位置，它是人类膈肌缺陷的候选基因。该提案的目的是确定 Fog2-Gata4 介导的肺和隔膜发育的途径基因和机制。在具体目标 1 中，将研究早期分支肺中与 Fog2 和 Gata4 共享表达模式的基因，并鉴定在肺叶出芽时受肺中 Fog2-Gata4 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 Fog2 和 Fog2-Gata4 介导的发育中的作用，因为视黄酸在膈肌和肺发育中发挥作用，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才能正常发育。由于 Fog2 和 Gata4 是人类肺和膈肌正常发育所必需的，并且都是 CDH 候选基因，因此该提案将确定控制这种发育的遗传途径，从而更好地了解人类膈肌缺陷的发病机制。项目叙述 - 先天性膈肌缺陷是相对常见的出生缺陷，死亡率很高，并且继发于相关肺部发育缺陷的长期发病率。 Fog2 和 Gata4 是正常膈肌和肺部发育所必需的基因。在本提案中，我们将通过研究与人类膈肌和肺缺陷相关的小鼠模型中 Fog2 和 Gata4 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.