Postnatal Alveolar Formation

产后肺泡形成

• 批准号: 9977262
• 负责人: Parviz Minoo Minoo
• 金额: $ 49.84万
• 依托单位: UNIVERSITY OF SOUTHERN CALIFORNIA
• 依托单位国家: 美国
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-09-01 至 2022-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9977262
• 关键词: Adult; Alveolar; Alveolus; Attention; Bioinformatics; Bronchopulmonary Dysplasia; Candidate Disease Gene; Cells; Characteristics; Child; Chronic Obstructive Airway Disease; Complex; Computer Analysis; Congenital alveolar dysplasia; Data; Defect; Development; Disease; Embryo; Endothelium; Epithelial; Epithelium; Failure; Foundations; Gene Expression Profiling; Genes; Genetic; Genetic Models; Goals; Hand; Health; Healthcare Systems; Human; IGF1 gene; Immune; Impairment; Infant; Investigation; Knowledge; Lead; Ligands; Lung; Lung diseases; Maintenance; Modeling; Molecular; Morphogenesis; Mus; Mutation; Myofibroblast; Neonatal; Neurodevelopmental Problem; PDGFA gene; Pathway interactions; Performance; Phase; Phenotype; Platelet-Derived Growth Factor alpha Receptor; Premature Infant; Preparation; Process; Pulmonary Emphysema; Recombinants; Regulator Genes; Reporting; Reproducibility; Respiration; Role; Schools; Signal Pathway; Signal Transduction; Societies; Specificity; Time; Tissue-Specific Gene Expression; Transforming Growth Factor beta; Validation; base; clinically relevant; comparative; cost; differential expression; experimental study; genetic approach; genetic element; genetic manipulation; improved; innovation; insight; interest; lung development; member; mouse model; mutant; postnatal; progenitor; tool; transcriptome sequencing

ABSTRACT:. The overarching long-term objective of this project is to identify principal genetic regulators of alveogenesis. Alveolar defects underlie many neonatal and adult lung diseases. Their arrested development is found in infants with BPD (BronchoPulmonary Dysplasia), while their destruction is characteristic of emphysematous lungs in adults. Despite significant clinical relevance, alveogenesis remains the least understood phase of lung development! We have developed 2 parallel, postnatal genetically-based models to analyze the molecular basis of alveogenesis. In Tgfβr1/2Gli mice, conditional postnatal inactivation of both Alk5 & Tβr2 in secondary crest myofibroblasts, SCMF blocks alveogenesis & disrupts epithelial morphogenesis. Similar strategy in the PdgfrαGli model also yields a nearly identical phenotype. We reasoned that due to nearly identical phenotypes, the two models must share in common some genetic elements whose role in alveogenesis is indispensable. Preliminary data using RNAseq/bioinformatics identified “pathway-specific” differentially expressed genes (DEG) for TGFβ and PDGFA/PDGFRα mutant models. Most importantly, as predicted, we identified a cluster of “common” genes which we propose contains a cluster of conserved core alveogenesis regulatory genes. These preliminary data, justify a more comprehensive and expanded analysis of DEG to improve the reliability of the RNAseq data (Specific Aim 1). In Specific Aim 2, we will validate and functionally characterize the common genes. A notable gene in the initial cluster is Igf1, which encodes the ligand for the IGF1 signaling pathway. We have selected IGF1 for further functional analyses (Specific Aims 3 and 4). HYPOTHESIS: TGFβ, PDGFA/PDGFRa & IGF1 form major sub-circuits of a complex signaling network in SCMF that controls alveogenesis via a cluster of downstream “alveogenesis regulatory genes”. This cluster is uniquely conserved & can be identified by comparative differential gene expression analysis using mutations in each of the three pathways & identifying the common DEG. The Specific Aims are: Specific Aim 1:. Identify Conserved SCMF Regulatory Genes That Control Alveogenesis Thru Analysis of Differentially Expressed Genes in PdgfrαGli1 & Tgfβr1/2Gli1 Lungs. Specific Aim 2:. Validate and Functionally Analyze Candidate Genes from Specific Aim 1. Specific Aim 3:. Develop Conditional, Cell-Targeted Genetic Model of IGF1 Signaling to Interrogate This Pathway as a Key Highly Conserved Regulatory Node in Alveolar Assembly & Epithelial Morphogenesis. Specific aim 4:. To Use Recombinant IGF1 to Identify Candidate IGF1-Regulated Alveogenesis Regulatory Genes via Rescue of Tgfβr1/2Gli1 Lungs. Impact: The alveolus is the functional unit of respiration. Its proper assembly requires coordinated function amongst endodermal, mesodermal, endothelial & perhaps immune cells. Elucidation of the mechanisms not only has an impact, but is necessary for understanding both neonatal (e.g. BPD, CDH & Alveolar Capillary Dysplasia) and adult pulmonary diseases (COPD, emphysema). The studies described here are grounded in strong rationale and preliminary data. While the proposal may appear over-ambitious, the volume of the preliminary data already at hand, makes certain the successful completion of the project within an RO1 time limit.

摘要： 该项目的首要长期目标是确定肺泡形成的主要遗传调节因子。 肺泡缺陷是许多新生儿和成人肺部疾病的基础。他们被逮捕的发展被发现在 患有BPD（支气管肺发育不良）的婴儿，而他们的破坏是肺气肿的特征 成人的肺尽管有显著的临床意义，肺泡形成仍然是肺的最不了解的阶段， 发展！ 我们已经开发了2个平行的、基于出生后遗传学的模型来分析 牙槽形成在Tgfβr1/2Gli小鼠中，次级嵴中Alk 5和Tβr2的条件性出生后失活， 在肌成纤维细胞中，SCMF阻断肺泡形成并破坏上皮形态发生。类似的战略在 PdgfrαGli模型也产生了几乎相同的表型。我们推断，由于几乎相同的表型， 这两种模型必须共享一些在肺泡形成中起不可或缺作用的遗传元件。 使用RNAseq/生物信息学的初步数据鉴定了“途径特异性”差异表达基因 (DEG)TGFβ和PDGFA/PDGFRα突变模型。最重要的是，正如预测的那样，我们发现了一个集群 我们提出的“共同”基因包含一组保守的核心肺泡形成调控基因。这些 初步数据，证明更全面和扩大分析DEG，以提高可靠性 RNAseq数据（Specific Aim 1）。在具体目标2中，我们将验证和功能性地描述常见的 基因.在初始簇中的一个值得注意的基因是Igf 1，其编码IGF 1信号通路的配体。我们 选择IGF 1进行进一步的功能分析（具体目标3和4）。 假设：TGFβ，PDGFA/PDGFRa和IGF 1形成了一个复杂信号网络的主要子电路， SCMF通过一组下游“肺泡形成调节基因”控制肺泡形成。该簇 独特保守的，可以通过比较差异基因表达分析，使用突变， 这三种途径中的每一种，并确定共同的DEG。具体目标是： 具体目标1：通过分析微卫星DNA序列鉴定控制肺泡形成的保守SCMF调控基因 Pdgfrα Gli 1和TGFβr1/2Gli 1肺组织中差异表达基因的研究 具体目标2：对特定目标1的候选基因进行克隆和功能分析。 具体目标3：开发IGF 1信号传导的条件性细胞靶向遗传模型来质疑这一点 作为肺泡组装和上皮形态发生中关键的高度保守的调节节点的通路。 具体目标4：利用重组IGF 1鉴定候选IGF 1调节的肺泡形成调节因子 通过拯救TGFβr1/2Gli 1肺的基因。 影响：肺泡是呼吸的功能单位。它的正确装配需要协调的功能 在内胚层、中胚层、内皮细胞和可能的免疫细胞中。阐明机制不仅 有影响，但对于了解新生儿（例如BPD，CDH和肺泡毛细血管发育不良） 和成人肺部疾病（COPD、肺气肿）。这里所描述的研究是基于强有力的理由 初步数据。虽然该提案可能显得过于雄心勃勃，但初步数据的数量已经 确保在RO 1时限内成功完成项目。