The role of TCF21 in coronary heart disease

TCF21在冠心病中的作用

基本信息

批准号：
9122122
负责人：
Robert Wirka
金额：
$ 6.68万
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 2018-07-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9122122
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 Histology Human Immunohistochemistry In Vitro Knock-out Label Laboratories Lead Lesion Light Link Location Mediating Molecular Molecular Profiling Mus Myocardial Infarction Pathway interactions Phenotype Plant Roots Play Population Reporter Reporter Genes Risk Risk Factors Role Rupture Series Shapes Smoking Smooth Muscle Myocytes Staging Stem cells Structure Time Transgenic Organisms Tunica Adventitia United States Vascular Smooth Muscle blood lipid cell type cost genetic variant genome wide association study genome-wide heart disease risk in vivo knock-down laser capture microdissection migration molecular phenotype mouse model novel novel therapeutic intervention programs public health relevance research study 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（由申请人提供）：虽然大约 40% 的冠心病 (CHD) 风险可归因于遗传变异，但我们目前仅了解导致这种风险的一小部分遗传变异。）指出与 CHD 相关的位点可能通过完全意想不到的机制促进 CHD 病理学，这提高了我们小组最近表明这些与 CHD 相关的多态性之一直接影响 CHD 的表达的可能性。 TCF21 基因与 CHD 病理学有关 TCF21 是一种基本的螺旋-环-螺旋转录因子，存在于冠状动脉发育的脉管系统中，在决定前体平滑肌细胞 (SMC) 的细胞命运决策中发挥着关键作用。表达细胞存在于人和鼠冠状动脉的外膜和主动脉中膜中，以响应 ApoE-/- 小鼠的动脉粥样硬化疾病。在模型中，这些表达 Tcf21 的细胞迁移到正在发展的病变中并在纤维帽处对齐，它们显示出 SMC 分化的证据，因为人们认为 SMC 可以增强纤维帽结构，从而防止斑块破裂和心肌。然而，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 如何调节前体 SMC 的表型和病变组成。体内，并阐明介导这些作用的分子途径，这些研究将显着扩大我们对 SMC 在 CHD 病理学中的作用的理解。在目标 1 中，我们将使用条件 Tcf21 敲除和 TCF21 转基因过表达 Apo。 E-/- 小鼠以确定 Tcf21 表达的变化如何影响动脉粥样硬化斑块内前体 SMC 的募集和表型，以及这些变化如何影响斑块结构。我们将通过组织学和免疫组织化学检查斑块组成和结构，特别关注保护性纤维帽。在目标 2 中，我们将使用从 Tcf21 报告小鼠中分离的细胞来表征 Tcf21 表达细胞。 Tcf21 谱系追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 Tcf21 表达细胞，并允许在不同时间点对其进行识别。这些 Tcf21 谱系追踪细胞将使用激光捕获显微切割从主动脉根部病变中分离出来，并进行 RNA 测序，这将在斑块形成过程中产生细胞基因表达的读数，这将允许对这些细胞进行分子表型分析。细胞，并将揭示形成易损动脉粥样硬化斑块的重要途径。