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，继发于相关肺发育不全，发病率和死亡率高。尽管这些缺陷具有重要的影响，但其发展的分子机制尚不清楚。我们在小鼠基因Fog2中发现了一种亚型突变，该突变导致膈肌缺陷伴原发性肺发育不全，而在患有后膈肌缺陷伴肺发育不全的婴儿中发现了一种新生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，其在肺部发育中的必要性验证了先天性膈肌缺陷新生儿也可能存在原发性肺部异常的假设。我们发现Fog2依赖的大叶发育是由Fog2- gata4相互作用介导的。Gata4也与小鼠横膈膜发育有关，并且基于其在先天性膈疝（CDH）细胞遗传学热点的位置，它是人类膈缺损的候选基因。本研究的目的是确定Fog2-Gata4介导肺和膈膜发育的途径基因和机制。在Specific Aim 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，并确定在肺叶出芽时肺中受Fog2-Gata4相互作用调节的基因。Specific Aim 2将评估维甲酸信号在Fog2和Fog2- gata4介导的发育中的作用，因为维甲酸在膈肌和肺发育中都起作用，维甲酸受体与Fog2相互作用。在Specific Aim 3中，将确定Fog2和Gata4是否需要后间质组织正常发育。由于Fog2和Gata4是正常人类肺和横膈膜发育所必需的，并且两者都是CDH候选基因，因此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膈膜缺陷的发病机制。

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.