Role of HIF-1alpha in Fetal Lung Epithelial Differentiation

HIF-1α 在胎儿肺上皮分化中的作用

基本信息

批准号：
7754867
负责人：
JOHN M SHANNON
金额：
$ 54.25万
依托单位：
CINCINNATI CHILDRENS HOSP MED CTR
依托单位国家：
美国
项目类别：
财政年份：
2007
资助国家：
美国
起止时间：
2007-02-01 至 2012-01-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/7754867
关键词：
A Mouse ABCA3 gene Affect Air Alveolar Anabolism Animals Atelectasis Binding Biological Assay Birth Breathing Breeding Cell Differentiation process Cell Maturation Data Development Distal Dominant-Negative Mutation EMSA Environment Enzymes Epithelial Epithelial Cells Epithelium Fetal Lung Fetus Gene Expression Gene Targeting Genes Genetic Transcription Gestational Age Glycogen Glycolysis HIF1A gene Hypoxia Hypoxia Inducible Factor In Vitro Link Lipids Liquid substance Lung Mediating Modeling Molecular Mus Phenotype Phospholipids Play Pregnancy Process Production Promoter Regions Proteins Pulmonary Surfactant-Associated Protein B Pulmonary Surfactants Regulation Research Personnel Respiratory Failure Respiratory physiology Response Elements Role Site Staging Surface Surface Tension System Testing Time Tissues Transgenes Transgenic Mice Transgenic Model Type II Epithelial Receptor Cell alveolar lamellar body alveolar type II cell critical period glucose uptake in utero in vivo lipid transport lung development lung maturation mouse model neonatal death neonate postnatal prenatal programs promoter respiratory distress syndrome restoration surfactant

项目摘要

DESCRIPTION (provided by applicant): Pulmonary surfactant, which is synthesized and secreted by alveolar type II cells, reduces surface tension at the air-liquid interface. The critical importance of pulmonary surfactant to normal lung function is underscored by the fact that a deficiency in pulmonary surfactant has been incontrovertibly linked to respiratory distress syndrome (RDS) in neonates. Synthesis and storage of pulmonary surfactant increase dramatically at the end of gestation. The molecular regulation of type II cell maturation, however, is not yet completely understood. Our preliminary data demonstrate that hypoxia inducible factor-la (HIF-1() plays an important role in lung epithelial differentiation. Cre-mediated deletion of HIF-1( in lung epithelial cells results in neonatal death from respiratory failure. Lungs from affected animals show significant reductions in several key components of the surfactant system. The present proposal will test the hypothesis that the hypoxic environment in utero is critical for increased surfactant production at the end of gestation, and that HIF-1( regulates key aspects of this process. We will examine the mechanism(s) by which HIF-1( influences lung epithelial cell differentiation in three specific aims. In the first specific aim we will use a transgenic model to determine how lung-specific HIF-1( deletion regulates overall surfactant phospholipid biosynthesis. Our preliminary data also indicate that expression of surfactant protein B (SP-B) and the lipid transporter ABCA3 are decreased in the epithelium of mice in which HIF-1( has been deleted. In the second specific aim we will use mice with lung-specific HIF-1( deletion to determine the role of HIF-1( in the regulation of SP-B and ABCA3. We will test the ability of HIF-1( to directly activate SP-B and ABCA3 transcription in vitro and define its interactions with hypoxia response elements. We will use a transgenic mouse model in which a constitutively active form of HIF-1( is inducibly expressed in the lung epithelium to determine if the effects of HIF-1( on SP-B and ABCA3 expression are direct. In third specific aim, we will express an inducible, dominant-negative form of HIF-1( in the lung epithelium to determine if HIF-1( is critical during particular periods of lung development. We will also use this model to determine if conditionally expressed SP-B or ABCA3 can reverse the HIF-l(-deleted phenotype. By defining the role of HIF-1(, these studies will provide important new information about the regulation of distal lung epithelial differentiation.

描述（申请人提供）：肺表面活性剂由II型肺泡细胞合成和分泌，可降低气液界面的表面张力。肺表面活性物质的缺乏无疑与新生儿呼吸窘迫综合征（RDS）有关，这一事实强调了肺表面活性物质对正常肺功能的至关重要性。妊娠末期肺表面活性物质的合成和储存急剧增加。然而，II 型细胞成熟的分子调控尚未完全了解。我们的初步数据表明缺氧诱导因子-1a (HIF-1() 在肺上皮分化中发挥重要作用。Cre 介导的肺上皮细胞中 HIF-1( 的缺失导致新生儿因呼吸衰竭而死亡。受影响动物的肺显示表面活性剂系统的几个关键成分显着减少，本提案将检验以下假设：子宫内的缺氧环境对于妊娠末期表面活性剂产量的增加至关重要，并且 HIF-1（调节其关键方面）。我们将在三个特定目标中研究 HIF-1( 影响肺上皮细胞分化的机制。在第一个特定目标中，我们将使用转基因模型来确定肺特异性 HIF-1( 缺失如何调节整体)。我们的初步数据还表明，在 HIF-1( 已被删除的小鼠的上皮细胞中，表面活性剂蛋白 B (SP-B) 和脂质转运蛋白 ABCA3 的表达降低。在第二个具体目标中，我们将使用肺特异性 HIF-1( 缺失) 的小鼠来确定 HIF-1( 在 SP-B 和 ABCA3 调节中的作用。我们将测试 HIF-1( 直接激活SP-B 和 ABCA3 体外转录并定义其与缺氧反应元件的相互作用我们将使用转基因小鼠模型，其中 HIF-1( 的组成型活性形式在肺上皮中诱导表达，以确定HIF-1( 在 SP-B 和 ABCA3 上的表达是直接的。在第三个具体目标中，我们将在肺上皮细胞中表达 HIF-1( 的可诱导、显性阴性形式，以确定 HIF-1( 在特定时期是否至关重要我们还将使用该模型来确定条件表达的 SP-B 或 ABCA3 是否可以逆转 HIF-1(-删除的表型)。通过定义 HIF-1( 的作用，这些研究将提供重要的新信息。关于远端肺上皮分化的调节。