The role of TCF21 in coronary heart disease

TCF21在冠心病中的作用

基本信息

批准号：
9321878
负责人：
Robert Wirka
金额：
$ 6.25万
依托单位：
STANFORD UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2015
资助国家：
美国
起止时间：
2015-08-01 至 2018-06-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9321878
关键词：
Affect Apolipoprotein E Architecture Arterial Fatty Streak Atherosclerosis BHLH Protein Blood Pressure Blood Vessels Caucasians Cell Count Cell Differentiation process Cells Cessation of life ChIP-seq Characteristics Chinese People Coronary Coronary artery Coronary heart disease Development Diabetes Mellitus Disease Disease Progression Embryo Endothelium Exhibits Gene Expression Genes Genetic Genetic Polymorphism Genetic Variation Genomics Heart Heritability Histology Human Immunohistochemistry In Vitro Knock-out Label Laboratories Lead Lesion Light Link Location Mediating Molecular Molecular Profiling Mus Muscle Cells Myocardial Infarction Pathway interactions Phenotype Plant Roots Play Population Recruitment Activity Reporter Reporter Genes Risk Risk Factors Role Rupture Series Shapes Smoking Smooth Muscle Myocytes Stem cells Structure Time Transgenic Organisms Tunica Adventitia United States Vascular Smooth Muscle blood lipid cell type cost disorder risk experimental study genetic variant genome wide association study genome-wide in vivo knock-down laser capture microdissection migration molecular phenotype mouse model novel novel therapeutic intervention programs public health relevance response therapeutic target transcriptome sequencing treatment strategy

项目摘要

DESCRIPTION (provided by applicant): Although approximately 40% of the risk for coronary heart disease (CHD) can be attributed to genetic variation, we currently understand only a fraction of genetic variants that contribute to this risk. Recent genome wide association studies (GWAS) have pointed to CHD-associated loci that could be contributing to CHD pathobiology via completely unexpected mechanisms, raising the possibility of new therapeutic strategies. Our group has recently shown that one of these CHD-associated polymorphisms directly affects expression of the TCF21 gene, implicating it in CHD pathobiology. TCF21 is a basic helix-loop-helix transcription factor that is found in the developing coronary vasculature, where it plays a critical role in determining cell fate decisions in precursor smooth muscle cells (SMCs). Tcf21-expressing cells are present in the adventitia of human and murine coronary arteries and the aortic media. In response to atherosclerotic disease in the ApoE-/- mouse model, these Tcf21-expressing cells migrate into the developing lesion and align at the fibrous cap, where they show evidence of SMC differentiation. This is especially intriguing given that SMCs are thought to strengthen the fibrous cap structure, which protects against plaque rupture and myocardial infarction. However, the role of Tcf21 in these precursor SMCs is unknown. The series of experiments described herein aim to determine how Tcf21 modulates the phenotype of precursor SMCs and lesion composition in vivo, and to elucidate the molecular pathways by which these effects are mediated. Together, these studies will significantly expand our understanding of the role of SMCs in CHD pathobiology. In Aim 1, we will use conditional Tcf21 knockout and TCF21 transgenic over-expressing Apo E-/- mice to determine how changes in Tcf21 expression affect precursor SMC recruitment and phenotype within the atherosclerotic plaque, and how these changes affect plaque architecture. We will use classical histology and immunohistochemistry to examine plaque composition and structure, with a special focus on the protective fibrous cap. We will track Tcf21-expressing cells via an inducible fluorescent reporter gene. In Aim 2, we will use cells isolated from Tcf21 reporter mice to characterize the in vivo molecular phenotype of Tcf21 lineage-traced cells. A Tcf21-specific fluorescent reporter gene will permanently label Tcf21-expressing cells and allow their identification at various time points during disease progression. These Tcf21 lineage-traced cells will be isolated from aortic root lesions using laser capture microdissection and will undergo RNA sequencing, which will produce a readout of cellular gene expression at progressive stages during plaque development. This will allow molecular phenotyping of these cells and will shed light on important pathways that shape the developing vulnerable atherosclerotic plaque.

描述（由适用提供）：尽管大约40％的冠状动脉疾病风险（CHD）可以归因于遗传变异，但我们目前仅了解造成这种风险的遗传变异的一部分。最近的基因组广泛的研究研究（GWAS）指出，与CHD相关的局部研究可能通过完全出乎意料的机制为CHD病理生物学做出贡献，从而提高了新的治疗策略的可能性。我们的小组最近表明，这些与CHD相关的多态性之一直接影响TCF21基因的表达，这意味着它在CHD病理生物学中。 TCF21是在发育中的冠状动脉脉管系统中发现的基本螺旋 - 环螺旋转录因子，在确定前体平滑肌细胞（SMC）中，它在确定细胞脂肪决策中起着至关重要的作用。表达TCF21的细胞存在于人和鼠冠状动脉和主动脉培养基的冒险中。为了应对APOE - / - 小鼠模型中的动脉粥样硬化疾病，这些表达TCF21的细胞迁移到发育中的病变中，并在纤维帽处对齐，在那里它们显示了SMC分化的证据。鉴于SMC被认为可以增强纤维帽结构，从而防止牙菌斑破裂和心肌梗塞，这一点尤其引人入胜。但是，TCF21在这些前体SMC中的作用尚不清楚。本文描述的一系列实验旨在确定TCF21如何调节体内前体SMC和病变组成的表型，并阐明这些作用介导的分子途径。总之，这些研究将大大扩展我们对SMC在CHD病理生物学中的作用的理解。在AIM 1中，我们将使用条件TCF21敲除和TCF21转基因过表达的Apo e - / - 小鼠来确定TCF21表达的变化如何影响动脉粥样硬化斑块中的SMC SMC募集和表型，以及这些变化如何影响斑块结构。我们将使用经典的组织学和免疫组织化学来检查斑块组成和结构，并特别关注受保护的纤维帽。我们将通过诱导的荧光报告基因跟踪表达TCF21的细胞。在AIM 2中，我们将使用从TCF21报告基因小鼠中分离出的细胞来表征TCF21谱系跟踪细胞的体内分子表型。 TCF21特异性荧光报告基因将永久标记表达TCF21的细胞，并允许其在各个时间点进行识别在疾病进展过程中。这些TCF21谱系跟踪的细胞将使用激光捕获显微解剖从主动脉根病变中分离出来，并将进行RNA测序，这将在斑块发育期间在渐进阶段产生细胞基因表达的读数。这将允许对这些细胞的分子表型化，并将揭示出塑造发展中脆弱的动脉粥样硬化斑块的重要途径。