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: 10874376
• 负责人: DANIEL YUHANG LI
• 金额: $ 6.91万
• 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/10874376
• 关键词: ATAC-seq; Address; Anatomy; Animals; Aorta; Apolipoprotein E; Arterial Fatty Streak; Atherosclerosis; BHLH Protein; Binding; Biological Assay; Blood Vessels; Cardiometabolic Disease; Cardiovascular Pathology; Cell Lineage; Cells; Characteristics; Chromatin; Chromosome Mapping; 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; Genome Mappings; Goals; High Fat Diet; Knock-out; Laboratories; Lesion; Lipids; Maps; Mediating; Mentors; Modeling; Molecular; Mus; Phenotype; Physicians; Proliferating; 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; cell dedifferentiation; 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.

项目总结 通过基因组，已有超过161个遗传位点与冠状动脉疾病(CAD)相关 由CARDIoGRAMplusC4D财团进行的广泛关联研究(GWAS)。然而，尽管 对冠心病认识的这些进展，治疗靶点超越了降脂治疗 尚未达到临床阶段。在这个发现的关键时刻，需要更好的机械性 在单细胞水平上表征遗传性冠心病风险基因座，以同时研究遗传和 疾病风险背后的表观遗传现象。Querterous实验室之前已经确定了TCF21 该基因定位于6q23.2位点处。一种平滑肌细胞的组合 (SMC)谱系追踪和单细胞RNA测序表明TCF21上调并促进 SMC去分化、增殖和向动脉粥样硬化斑块迁移。TCF21的表达有助于 SMC向保护性纤维帽的表型转变，产生成纤维细胞样细胞 “纤维肌细胞”(FMC)。我们现在正在研究这种在多个发展时间点的过渡状态 单细胞转录和表观基因组学在动脉粥样硬化ApoE基因敲除模型中的广泛发现 与SMC-FMC过渡细胞状态相关的染色质可及性的变化。而TCF21的损失 导致FMC减少50%以上，SMC中仍有一部分人可以帮助 FMC和纤维帽。与TCF21协同促进SMC转化的基因调控网络， 而这些网络的下游靶基因仍然未知。其背后的中心假说 这一建议是TCF21通过其促进能力对CAD风险起到保护作用 血管壁应力环境下SMC的表型转化。为了解决这一假设， 申请者将研究血管疾病和血管疾病中TCF21过度表达的SMC特异性模型 通过先进的转录和转录技术表征TCF21作用增强的疾病后果 同时评估单细胞基因转录和染色质可及性的表观遗传学工具 在血管组织中结合scRNAseq和scATACseq。目标1将检查增加的总体影响 TCF21在大鼠动脉粥样硬化斑块中的表达及细胞组成和解剖 转基因过度表达的动物。目标2将阐明转录和表观遗传机制，通过 单细胞分析中哪个TCF21介导SMC去分化和向FMC表型转化 多组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的过度表达是否增加了SMC向FMC的转变，ii)确实 增加SMC到FMC的转变促进更稳定的斑块表型，以及III)TCF21如何调节 表观遗传和转录格局促进SMC向保护性FMC表型转变。