TCF21 is a causal coronary artery disease gene that modulates coronary smooth muscle phenotypic transition via epigenetic mechanisms

TCF21 是一种致病性冠状动脉疾病基因，可通过表观遗传机制调节冠状动脉平滑肌表型转变

• 批准号: 10536419
• 负责人: DANIEL YUHANG LI
• 金额: $ 6.68万
• 依托单位: STANFORD UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-09-02 至 2025-09-01
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10536419
• 关键词: ATAC-seq; Address; Anatomy; Animals; Apolipoprotein E; Arterial Fatty Streak; Atherosclerosis; BHLH Protein; Binding; Biological Assay; Blood Vessels; Cardiometabolic Disease; Cardiovascular Pathology; Cell Lineage; Cells; Characteristics; Chromatin; Clinical; Computational Technique; Coronary; Coronary Arteriosclerosis; Coronary heart disease; Development; Disease; Epigenetic Process; Evaluation; Fibroblasts; Functional disorder; Gene Expression; Genes; Genetic; Genetic Transcription; Genetic study; Goals; High Fat Diet; Knock-out; Laboratories; Lesion; Lipids; Maps; Mediating; Mentors; Modeling; Molecular; Mus; Phenotype; Physicians; Regulator Genes; Regulatory Pathway; Research; Research Personnel; Scientist; Smooth Muscle; Smooth Muscle Myocytes; Stress; System; Therapeutic; Time; Tissues; Transgenic Organisms; Transitional Cell; Translating; Variant; Vascular Diseases; Vascular Smooth Muscle; Work; disorder risk; epigenomics; gene network; gene regulatory network; genome wide association study; genome-wide; genomic locus; in vivo; migration; mouse model; multiple omics; novel; overexpression; phenotypic biomarker; prevent; protective effect; response; risk variant; single cell analysis; single-cell RNA sequencing; therapeutic target; tool; transcription factor; transcriptome sequencing; transcriptomics; vascular stress

PROJECT SUMMARY More than 161 genetic loci have been associated with coronary artery disease (CAD) through the genome wide association studies (GWAS) conducted by the CARDIoGRAMplusC4D consortium. However, despite such advances in the understanding of coronary disease, therapeutic targets beyond lipid lowering therapies have yet to reach the clinical stage. At this critical juncture for discovery, there is a need for better mechanistic characterization of the genetic CAD risk loci at the single cell level to simultaneously study the genetic and epigenetic phenomena underlying disease risk. The Quertermous laboratory has previously identified TCF21 as the CAD associated gene mapped by GWAS at the 6q23.2 locus. A combination of smooth muscle cell (SMC) lineage tracing and single cell RNA sequencing has shown that Tcf21 is upregulated and promotes SMC de-differentiation, proliferation and migration into atherosclerotic plaque. TCF21 expression contributes to the phenotypic transition of SMC to the protective fibrous cap, producing fibroblast-like cells termed “fibromyocytes” (FMC). We are now studying this transitional state at multiple developmental time points with single cell transcriptomics and epigenomics in the ApoE knockout model of atherosclerosis and find wide variation in chromatin accessibility associated with the SMC-FMC transitional cell state. While loss of Tcf21 produces more than a 50% decrease in FMC, there remains a subpopulation of SMC that can contribute to FMC and the fibrous cap. The gene regulatory networks that cooperate with TCF21 to promote SMC transition, and the downstream target genes of these networks remain unknown. The central hypothesis underlying this proposal is that TCF21 exerts a protective effect toward CAD risk through its ability to promote phenotypic transition of SMC in the setting of vascular wall stress. To address this hypothesis, the applicant will study a SMC-specific model of Tcf21 over-expression in the setting of vascular disease and characterize the disease consequences of increased Tcf21 action through cutting-edge transcriptomic and epigenetic tools to simultaneously evaluate single cell gene transcription and chromatin accessibility through combined scRNAseq with scATACseq in vascular tissue. Aim 1 will examine the overall effect of increased Tcf21 expression on SMC phenotype as well as atherosclerotic plaque cellular composition and anatomy in transgenic over-expressing animals. Aim 2 will elucidate the transcriptional and epigenetic mechanisms by which Tcf21 mediates SMC de-differentiation and transition to the FMC phenotype using analysis of single cell multi-omic RNAseq and ATACseq. This study will address fundamental questions related to vascular disease pathophysiology, including: i) does TCF21 over-expression increase the SMC to FMC transition, ii) does increased SMC to FMC transition promote a more stable plaque phenotype, and iii) how does TCF21 regulate the epigenetic and transcriptional landscape to promote SMC transition to a protective FMC phenotype.

项目概要 超过 161 个基因位点通过基因组与冠状动脉疾病 (CAD) 相关 由 CARDIoGRAMplusC4D 联盟进行的广泛关联研究 (GWAS)。然而，尽管 对冠心病的理解取得了如此进展，治疗目标超越了降脂疗法 尚未达到临床阶段。在这个发现的关键时刻，需要更好的机制 在单细胞水平上表征 CAD 遗传风险位点，以同时研究遗传和 疾病风险背后的表观遗传现象。 Quertermous 实验室此前已鉴定出 TCF21 作为通过 GWAS 在 6q23.2 位点定位的 CAD 相关基因。平滑肌细胞的组合 (SMC)谱系追踪和单细胞RNA测序表明Tcf21上调并促进 SMC 去分化、增殖并迁移至动脉粥样硬化斑块。 TCF21 表达有助于 SMC 向保护性纤维帽的表型转变，产生称为成纤维细胞样细胞 “纤维肌细胞”（FMC）。我们现在正在多个发育时间点研究这种过渡状态 单细胞转录组学和表观基因组学在动脉粥样硬化 ApoE 敲除模型中的应用并发现广泛 与 SMC-FMC 过渡细胞状态相关的染色质可及性的变化。当 Tcf21 丢失时 使 FMC 减少 50% 以上，但仍有一个 SMC 亚群可以促进 FMC 和纤维帽。与TCF21合作促进SMC转型的基因调控网络， 这些网络的下游靶基因仍然未知。所依据的中心假设 该提案认为，TCF21 通过其促进 CAD 风险的能力发挥保护作用 血管壁应力环境下​​ SMC 的表型转变。为了解决这个假设， 申请人将研究血管疾病背景下 Tcf21 过度表达的 SMC 特异性模型 通过尖端转录组学和技术描述 Tcf21 作用增加的疾病后果 表观遗传工具可同时评估单细胞基因转录和染色质可及性 在血管组织中将 scRNAseq 与 scATACseq 相结合。目标 1 将检查增加的总体效果 Tcf21 对 SMC 表型的表达以及动脉粥样硬化斑块细胞组成和解剖结构 转基因过度表达动物。目标 2 将通过以下方式阐明转录和表观遗传机制： 通过单细胞分析，Tcf21 介导 SMC 去分化和向 FMC 表型的转变 多组学 RNAseq 和 ATACseq。这项研究将解决与血管疾病相关的基本问题 病理生理学，包括：i) TCF21 过度表达是否会增加 SMC 向 FMC 的转变，ii) 是否会增加 SMC 向 FMC 的转变？ SMC 向 FMC 转变的增加促进了更稳定的斑块表型，以及 iii) TCF21 如何调节 表观遗传和转录景观促进 SMC 向保护性 FMC 表型转变。