Intercalated disc-nuclear lamina coupling as a molecular substrate for arrhythmogenic cardiomyopathy

闰盘-核层耦合作为致心律失常性心肌病的分子底物

• 批准号: 10713689
• 负责人: Eric M Small
• 金额: $ 69.92万
• 依托单位: UNIVERSITY OF ROCHESTER
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-08-01 至 2027-07-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10713689
• 关键词: Acceleration; Adhesions; Architecture; Arrhythmia; Arrhythmogenic Right Ventricular Dysplasia; Attention; Cardiac; Cardiac Myocytes; Cardiomyopathies; Cell Communication; Cell Death; Cell Nucleus; Cell membrane; Cell surface; Cell-Matrix Junction; Cells; Chromatin; Code; Complex; Coupling; Cytoskeleton; DNA Damage; Data; Desmin; Desmosomes; Disease; Disease Progression; Ecosystem; Filament; Foundations; Functional disorder; Gene Expression; Genes; Genetic Diseases; Genetic Epistasis; Genetic Transcription; Genome; Genomics; Heart Arrest; Hereditary Disease; Homeostasis; Human; Image; Induced Mutation; Intercalated disc; Intermediate Filaments; Knowledge; Lamin Type A; Lamins; Life; Link; Mechanics; Mediating; Methods; Microscopy; Microtubules; Modernization; Molecular; Morbidity - disease rate; Mus; Muscle Cells; Mutant Strains Mice; Mutation; Myocardial; Myocardial dysfunction; Myocardium; Nuclear; Nuclear Envelope; Nuclear Lamina; Nuclear Structure; Onset of illness; Organelles; Pathogenesis; Pathologic; Pathway interactions; Patients; Physiology; Proteins; Proteome; Proteomics; Publishing; Reporting; Research; Role; Sampling; Signal Transduction; Structure; Surface; TP53 gene; Testing; Tissues; Translating; Variant; Ventricular; Ventricular Arrhythmia; Work; arrhythmogenic cardiomyopathy; desmoplakin; disease phenotype; druggable target; env Gene Products; experimental study; gene repression; mechanical load; molecular imaging; mortality; mouse model; novel therapeutic intervention; pharmacologic; plakophilin 2; prevent; response; scaffold; single molecule; transcriptional reprogramming; transcriptomics; transmission process

Plakophilin-2 (PKP2) is classically defined as a protein of the desmosome, an intercellular adhesion structure residing in the cardiac intercalated disc (ID). Mutations in PKP2 associate with most cases of gene-positive arrhythmogenic right ventricular cardiomyopathy (ARVC), a disease characterized by high propensity to life- threatening arrhythmias and myocardial structural damage, often of right ventricular predominance. Much attention has been given to the loss of cell-cell attachment at the ID as a disease mechanism. Yet, it is becoming evident that PKP2 mutations also lead to an array of poorly understood cardiomyocyte (CM)-intrinsic disturbances. Desmin intermediate filaments are anchored to the desmosome in a PKP2-dependent manner, supporting CM structural integrity and facilitating communication from the cell surface to the nucleus. Our prior work in mouse models and human patient samples found PKP2 mutation disrupts CM nuclear envelope (NE) integrity and leads to DNA damage. Based on published reports and our preliminary data, we hypothesize that PKP2 deficiency, or disease relevant PKP2 mutations, disrupt the structural, functional and molecular integrity of the cardiomyocyte nuclear envelope, leading to genomic reorganization, the DNA damage response, and altered transcription. The following aims will investigate how PKP2 deficiency disrupts the nucleus to accelerate ARVC disease progression. Aim 1: Define the impact of PKP2 deficiency on the cardiomyocyte nuclear lamina protein interactome. We hypothesize that PKP2 deficiency alters the proteome of the cardiomyocyte NE, and that this disruption is an early trigger for the disease phenotype. We will interrogate changes in the molecular ecosystem of the cardiomyocyte NE after loss of PKP2 expression using proteomics and single molecule imaging. Aim 2: Define the impact of PKP2 deficiency on cardiomyocyte genomic organization. We hypothesize that loss of NE integrity in PKP2 deficient CMs disrupts genomic organization at Lamin Associated Domains and causes transcriptional remodeling. We will determine how structural damage is transmitted from the cell membrane to the genome, focusing on changes that occur in the vicinity of the NE through advanced imaging, genomic and transcriptomic approaches. Aim 3: Investigate strategies to reduce DDR and delay cardiomyopathy in PKP2 deficient mice. We hypothesize data that PKP2 mutation induces P53-dependent DNA damage response (DDR), which may exacerbate ARVC disease progression. Genetic epistasis experiments and pharmacological approaches will investigate how the P53-dependent DDR contributes to PKP2-dependent cardiomyopathy. Defining pathological changes to nuclear architecture that precede overt myocardial structural remodeling will reveal exciting opportunities for new therapeutic strategies aimed at slowing ARVC disease progression by restoring nuclear envelope homeostasis or preventing the DNA damage response.

Plakophilin-2 (PKP2) 被经典地定义为桥粒蛋白，一种细胞间粘附结构 位于心脏闰盘（ID）中。 PKP2 突变与大多数基因阳性病例相关 致心律失常性右心室心肌病（ARVC），一种以高生命倾向为特征的疾病 威胁性心律失常和心肌结构损伤，通常以右心室为主。很多 作为一种疾病机制，ID 处细胞与细胞附着的丧失已引起人们的关注。然而，它正在成为 显然，PKP2 突变也会导致一系列人们对心肌细胞 (CM) 固有的知之甚少的影响。 干扰。结蛋白中间丝以 PKP2 依赖性方式锚定在桥粒上， 支持 CM 结构完整性并促进从细胞表面到细胞核的通讯。我们之前的 在小鼠模型和人类患者样本中的研究发现 PKP2 突变会破坏 CM 核膜 (NE) 完整性并导致 DNA 损伤。根据已发表的报告和我们的初步数据，我们假设 PKP2 缺陷或疾病相关的 PKP2 突变会破坏结构、功能和分子完整性 心肌细胞核膜的改变，导致基因组重组、DNA损伤反应，以及 改变转录。以下目标将研究 PKP2 缺陷如何破坏细胞核加速 ARVC 疾病进展。 目标 1：确定 PKP2 缺陷对心肌细胞核层蛋白相互作用组的影响。 我们假设 PKP2 缺陷会改变心肌细胞 NE 的蛋白质组，并且这种破坏是 疾病表型的早期触发因素。我们将探究分子生态系统的变化 使用蛋白质组学和单分子成像观察 PKP2 表达缺失后的心肌细胞 NE。 目标 2：确定 PKP2 缺陷对心肌细胞基因组组织的影响。 我们假设 PKP2 缺陷 CM 中 NE 完整性的丧失会破坏核纤层蛋白的基因组组织 相关结构域并导致转录重塑。我们将确定结构损坏的程度 从细胞膜传递到基因组，重点关注NE附近发生的变化 通过先进的成像、基因组和转录组方法。 目标 3：研究减少 DDR 并延缓 PKP2 缺陷小鼠心肌病发生的策略。 我们假设 PKP2 突变诱导 P53 依赖性 DNA 损伤反应 (DDR) 的数据，这可能 加剧 ARVC 疾病进展。遗传上位实验和药理学方法将 研究 P53 依赖性 DDR 如何导致 PKP2 依赖性心肌病。 定义明显心肌结构重塑之前的核结构病理变化 将揭示旨在减缓 ARVC 疾病进展的新治疗策略的令人兴奋的机会 恢复核膜稳态或防止 DNA 损伤反应。