Molecular control of a novel transitional cell state in alveolar regeneration

肺泡再生中新型过渡细胞状态的分子控制

基本信息

批准号：
10204108
负责人：
Purushothama Rao Tata
金额：
$ 49.84万
依托单位：
DUKE UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2020
资助国家：
美国
起止时间：
2020-07-01 至 2024-06-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10204108
关键词：
Ablation Address Alveolar Automobile Driving Biological Assay Cell Adhesion Cell Cycle Arrest Cell Cycle Regulation Cell Differentiation process Cell surface Cells Cessation of life Characteristics Chronic Obstructive Airway Disease Chronic stress Clinical DNA Damage DNA Repair DNA Sequence Alteration Data Defect Development Disease Engraftment Environmental Risk Factor Epithelial Epithelial Cells Fibrosis Foundations Future Genes Genetic Genetic Transcription Goals Human Inflammation Injury Lead Lung diseases Maintenance Mediating Modeling Molecular Multiple Trauma Mutation Natural regeneration Organoids Outcome Pathogenesis Pathway Analysis Pathway interactions Pattern Pharmacology Process Pulmonary Emphysema Pulmonary Fibrosis Reporter Role SOX4 gene Shapes Signal Pathway Signal Transduction Specimen Stretching Structure TP53 gene Testing Therapeutic Thinness Tissues Transforming Growth Factor beta Transgenic Organisms Transitional Cell United States Work alveolar epithelium alveolar homeostasis base clinically relevant epithelial stem cell gain of function genome wide association study in vivo loss of function lung injury mouse model notch protein novel novel therapeutics progenitor programs prospective repaired response self-renewal stem cells tool transcription factor transcriptomics

项目摘要

SUMMARY Alveolar injury and ineffective repair have been hypothesized to underlie the pathogenesis of chronic obstructive pulmonary disease and pulmonary fibrosis. While genome-wide association studies and clinical specimens have suggested a role for chronic stress, inflammation and DNA damage signaling, the underlying mechanisms and the cell states in which the above pathways are dysregulated during alveolar regeneration remain elusive. In our recent studies, using organoids, single cell transcriptomics and in vivo lung injury models, we uncovered a previously uncharacterized, transient, pre-AEC1 transitional cell state (PATS), traversing between AEC2 and AEC1 in alveolar regeneration. Interestingly, pathway analysis for genes expressed in PATS showed a significant enrichment for targets of transcription factors TP53 and SOX4, and DNA damage repair pathway. We also found that this cell state is vulnerable to stretch mediated DNA damage during differentiation of cuboidal AEC2 into extremely flat and thin AEC1. Conditional ablation of Tp53 and Sox4 in AEC2s revealed a dramatic decrease in the number of AEC1, and a significant increase in the number of PATS. These data suggest an essential role for transcription factors TP53 and SOX4 in regulating AEC2 to AEC1 differentiation via pre-AEC1 transitional state and the DNA damage repair during alveolar regeneration. Based on our preliminary data, we hypothesize that the AEC2 progenitors go through a novel and molecularly distinct pre-AEC1 transitional state to differentiate into AEC1. We also hypothesize that TP53 and SOX4 -mediated mechanisms are essential for the cell cycle arrest, cell adhesion, cell stretching, and DNA damage repair pathway during differentiation of AEC2 to AEC1. The major objectives of this proposal are to molecularly and functionally characterize the newly identified pre- AEC1 transitional state and to study the mechanisms governing this cell state in alveolar regeneration. In Aim1, we will study the molecular identity, the temporal dynamics and the plasticity of a novel pre-AEC1 transitional state in alveolar regeneration. In Aim2, we will test the hypothesis that TP53 and SOX4 mediated mechanisms control cell cycle regulation, cell adhesion, and DNA damage repair pathways in pre-AEC1 transitional state during AEC2 differentiation into AEC1. We will use organoid models, in vivo genetic and pharmacological loss- of-function models, and molecular assays to study these specific aims. This work has taken on added importance, as recent genome-wide association studies revealed mutations in the components of the DNA damage repair signaling as one of the major drivers for emphysema and pulmonary fibrosis. Therefore, our finding that stretch associated DNA damage in the pre-AEC1 transitional state makes it potentially vulnerable to lung diseases. Thus, the outcomes from the proposed studies will have broader significance and will lay the foundation for future studies involving human alveolar regeneration and diseases.

概括据推测，肺泡损伤和无效修复是慢性阻塞性肺疾病发病机制的基础。肺部疾病和肺纤维化。虽然全基因组关联研究和临床标本已提出了慢性压力、炎症和 DNA 损伤信号传导的作用、潜在机制和在肺泡再生过程中上述途径失调的细胞状态仍然难以捉摸。在我们最近的研究中，利用类器官、单细胞转录组学和体内肺损伤模型，我们发现先前未表征的、短暂的、AEC1 之前的过渡细胞状态 (PATS)，在 AEC2 和 AEC1 在肺泡再生中的作用。有趣的是，PATS 中表达的基因的通路分析表明，转录因子 TP53 和 SOX4 靶点的富集以及 DNA 损伤修复途径。我们还发现在立方形 AEC2 分化为极其扁平且薄的 AEC1。 AEC2 中 Tp53 和 Sox4 的条件消融揭示了 AEC2 中 Tp53 和 Sox4 的急剧下降 AEC1 的数量，以及 PATS 数量的显着增加。这些数据表明了重要作用转录因子 TP53 和 SOX4 通过前 AEC1 过渡调控 AEC2 向 AEC1 分化状态和肺泡再生过程中的 DNA 损伤修复。根据我们的初步数据，我们假设 AEC2 祖细胞经历了一种新颖且分子上独特的 AEC1 前过渡状态分化为AEC1。我们还假设 TP53 和 SOX4 介导的机制是必不可少的用于细胞周期停滞、细胞粘附、细胞拉伸和 DNA 损伤修复途径 AEC2 与 AEC1 的分化。该提案的主要目标是从分子和功能上表征新发现的预- AEC1 过渡状态并研究肺泡再生中控制该细胞状态的机制。在目标 1 中，我们将研究一种新型 pre-AEC1 过渡蛋白的分子特性、时间动力学和可塑性肺泡再生状态。在 Aim2 中，我们将检验 TP53 和 SOX4 介导机制的假设控制 AEC1 前过渡状态的细胞周期调节、细胞粘附和 DNA 损伤修复途径 AEC2 分化为 AEC1 期间。我们将使用类器官模型，体内遗传和药理损失- 功能模型和分子测定来研究这些特定目标。这项工作已进行了补充重要性，因为最近的全基因组关联研究揭示了 DNA 成分的突变损伤修复信号是肺气肿和肺纤维化的主要驱动因素之一。因此，我们的发现 AEC1 前过渡状态中与拉伸相关的 DNA 损伤使其可能容易受到肺部疾病。因此，拟议研究的结果将具有更广泛的意义，并将奠定为未来涉及人类肺泡再生和疾病的研究奠定了基础。