Elucidating the epigenetic regulation of extracellular matrix and virus-induced fibroblast activation

阐明细胞外基质和病毒诱导的成纤维细胞活化的表观遗传调控

基本信息

批准号：
10572863
负责人：
Jaye C Gardiner
金额：
$ 12.5万
依托单位：
RESEARCH INST OF FOX CHASE CAN CTR
依托单位国家：
美国
项目类别：
财政年份：
2023
资助国家：
美国
起止时间：
2023-02-01 至 2025-01-31
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10572863
关键词：
2019-nCoV ATAC-seq Affect Applied Skills Bacterial Infections Binding Binding Proteins Biological Markers Categories Cells Cellular biology ChIP-seq Chemicals Chromatin Chronic Obstructive Pulmonary Disease Communication Complex Connective Tissue Coxsackie B Viruses Cues DNA-Directed RNA Polymerase Data Deposition Development Disease Environment Epigenetic Process Excision Extracellular Matrix Failure Fibroblasts Fibrosis Future Gene Expression Gene Expression Regulation Genes Genetic Transcription Goals Grant Growth Factor Hepatitis B Virus Histone Acetylation Human In Vitro Infection Inflammatory Response Influenza A virus Knockout Mice Lead Link Liver Fibrosis Malignant Neoplasms Mediating Mesenchymal Molecular Myofibroblast Nucleosomes Organ Organ failure Pancreas Pancreatitis Pathologic Patient Isolation Phenotype Play Predisposition Process Pulmonary Fibrosis Regulation Reporting Research Resolution Respiratory Tract Infections Respiratory syncytial virus Role Signal Transduction Simplexvirus Specificity Stimulus Testing Time Tissue Sample Tissues Transcription Coactivator Transcription Initiation Transforming Growth Factor beta Tropism Viral Virus Virus Diseases Work brahma chromatin remodeling clinically relevant cytokine epigenetic memory epigenetic regulation experimental study extracellular falls human pathogen idiopathic pulmonary fibrosis in vivo innovation insight interstitial memory acquisition mouse model netrin-G1 novel pancreatic cancer patients programs recruit repaired response skill acquisition small molecule inhibitor therapeutic target tissue repair transcriptome sequencing virology wound healing

项目摘要

PROJECT SUMMARY While wound healing processes are vital for successful organismal tissue repair, failure to turn off these mechanisms lead to the excessive accumulation of the extracellular matrix (ECM) and the development of fibrosis. Although recent research is beginning to illuminate the circumstances that allow for fibrosis resolution, most fibrotic conditions remain unresolved; resulting in organ failure or a predisposition to cancer. While the triggers for fibrotic diseases fall within a handful of categories, including viral/bacterial infection, tissue damage, and chemical insults, all induce the sustained activation of mesenchymal cells into myofibroblasts. Besides transforming growth factor β (TGF-β), which is a major activator of fibroblasts, the ECM also has the ability to alter a fibroblast’s activation state. We and others have demonstrated that this activated phenotype can persist despite the cell’s removal from fibrotic tissues, suggesting that fibroblasts have an “epigenetic memory” acquired during activation and retained thereafter. However, the molecular details underlying epigenetic regulation during myofibroblastic activation and whether these details are universal despite the activation trigger is unknown. One potential mechanism of myofibroblast regulation is through the ECM-dependent expression of pro- fibrotic genes. Gene expression is a tightly regulated process that requires chromatin remodeling, binding of transcriptional activators, and recruitment of RNA polymerase to initiate transcription. As such, the structural reorganization of the chromatin plays a large role in the temporal regulation and tissue specificity of gene expression. Brahma-related gene 1 (BRG1) is a central catalytic ATP-subunit of the BAF (BRG1/BRM1- associated factor) complex which works to drive chromatin accessibility via nucleosome eviction. BRG1 has also been shown to regulate ECM gene expression in both healthy and virally-induced fibrotic contexts. Moreover, preliminary data found that BRG1-deficient pancreatic fibroblasts lost the expression of a key functional regulator, Netrin G1. Taken together, this suggests a role of BRG1 in regulating myofibroblast pro-fibrotic genes. The overarching goal of this proposal is to test the hypothesis that the ECM and fibrosis-inducing viruses alter fibroblasts’ chromatin landscape in a BRG1-dependent manner and contribute to the epigenetic memory that underlies myofibroblastic function. To test this hypothesis, Aim 1 will first investigate BRG1’s involvement in pancreatic fibroblast activation in vitro and whether this is regulated by ECM-mediated signaling. In Aim 2, experiments will focus on the role of BRG1 in regulating disease formation by using an in vivo pancreatitis mouse model. Finally, Aim 3 will build on these lessons and investigate the mechanisms by which fibrosis-inducing viruses cause myofibroblast activation, beginning with the frequent human pathogen, Influenza A virus. By using a novel perspective to understanding fibrosis, this research provides insights that will advance cell biology, epigenetics, and virology, as well as reveal how the ECM/viruses create a pro-fibrotic state.

项目概要虽然伤口愈合过程对于成功的生物组织修复至关重要，但未能关闭这些过程机制导致细胞外基质（ECM）过度积累并发展尽管最近的研究开始阐明纤维化消退的环境，大多数纤维化病症仍未得到解决；导致器官衰竭或易患癌症。纤维化疾病的诱因分为几类，包括病毒/细菌感染、组织损伤、和化学损伤，都会诱导间充质细胞持续活化为肌成纤维细胞。转化生长因子 β (TGF-β) 是成纤维细胞的主要激活剂，ECM 还能够我们和其他人已经证明这种激活的表型可以持续存在。尽管细胞从纤维化组织中去除，这表明成纤维细胞具有获得的“表观遗传记忆” 然而，在激活期间并保留了表观遗传调控的分子细节。肌成纤维细胞激活以及尽管激活触发因素这些细节是否具有普遍性尚不清楚。肌成纤维细胞调节的一种潜在机制是通过 ECM 依赖性表达纤维化基因的表达是一个严格调控的过程，需要染色质重塑、结合。转录激活剂，以及招募 RNA 聚合酶来启动转录。染色质重组在基因的时间调控和组织特异性中发挥着重要作用 Brahma 相关基因 1 (BRG1) 是 BAF (BRG1/BRM1-) 的中心催化 ATP 亚基。相关因子）复合物也通过核小体驱逐驱动染色质可及性。已被证明可以在健康和病毒诱导的纤维化环境中调节 ECM 基因表达。初步数据发现，BRG1缺陷的胰腺成纤维细胞失去了关键功能的表达综上所述，这表明 BRG1 在调节肌成纤维细胞促纤维化基因中发挥作用。该提案的总体目标是检验 ECM 和纤维化诱导病毒改变的假设以 BRG1 依赖性方式改变成纤维细胞的染色质景观，并有助于表观遗传记忆是肌成纤维细胞功能的基础。为了检验这一假设，目标 1 将首先研究 BRG1 在胰腺成纤维细胞激活中的作用体外实验以及这是否受到 ECM 介导的信号传导的调节。在目标 2 中，实验将重点关注的作用。 BRG1 通过使用体内胰腺炎小鼠模型来调节疾病形成最后，Aim 3 将在此基础上进行。这些教训并研究纤维化诱导病毒引起肌成纤维细胞激活的机制，从人类常见的病原体甲型流感病毒开始，用一种新颖的视角来理解。纤维化，这项研究提供了一些见解，将推动细胞生物学、表观遗传学和病毒学的发展，并揭示 ECM/病毒如何产生促纤维化状态。