Early Cardiac Progenitors

早期心脏祖细胞

基本信息

批准号：
10212085
负责人：
Benoit Gaetan Bruneau
金额：
$ 56.49万
依托单位：
J. DAVID GLADSTONE INSTITUTES
依托单位国家：
美国
项目类别：
财政年份：
2013
资助国家：
美国
起止时间：
2013-07-01 至 2025-03-31
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10212085
关键词：
ATAC-seq Adult Affect Arrhythmia Behavior Birds Birth Cardiac Cardiac development Cardiomyopathies Cause of Death Cells Chromatin Complex Congenital Heart Defects DNA Defect Embryo Embryonic Development Embryonic Heart Enhancers Event Gene Expression Gene Expression Profiling Genes Genetic Genetic Transcription Genetic study Genome Genomics Heart Heart Diseases Human Human Genetics Image Impairment In Vitro Individual Instruction Knock-out Knowledge Label Lead Light Live Birth Mesoderm Modality Molecular Morphogenesis Mus Nature Organ Plant Roots Population Positioning Attribute Process Recipe Regulator Genes Regulatory Element Reporter Signal Transduction Testing Transgenic Organisms Tube Zebrafish base cardiogenesis cell motility embryonic stem cell gastrulation genome-wide heart cell in vivo induced pluripotent stem cell infant death microscopic imaging migration mutant precursor cell progenitor response single-cell RNA sequencing transcription factor transcriptome

项目摘要

SUMMARY The mammalian heart forms early in embryogenesis, and defects in its formation are at the root of congenital heart defects (CHDs), affecting 1–2% of live births. The gene regulatory networks that are disturbed in CHDs have begun to be elucidated from large-scale human genetic studies. Many of the genes causing CHD are transcriptional regulators, and several of these are also associated with genetics of adult heart disease, such as cardiomyopathy and arrhythmias. A complete understanding of the birth of cardiac progenitors and the first steps that lead to the formation of the embryonic heart has implications for both CHD and adult heart disease. The origins of the heart in embryogenesis have been defined as beginning in mesoderm that arises during gastrulation. We previously defined a specific enhancer of Smarcd3 that labels a very restricted subpopulation of Mesp1 lineage-labeled mesoderm, which contribute almost exclusively to the heart. Embryogenesis is a highly dynamic process, whereby complex coordinated cell movements position organ precursors for precise morphogenesis, and control the response to potent morphogenetic signaling gradients. While aspects of dynamic cardiac morphogenesis have been visualized in the avian embryo, our knowledge of cardiac progenitor emergence and behaviour in the mouse embryo is lacking. We have been able to culture and image live lineage- labeled mouse embryos, and will leverage this exciting approach to investigate mammalian cardiac development. We hypothesize that differentiation, migration, and contribution to early heart formation of early cardiac progenitors are regulated by a specific gene regulatory network composed of temporally-modulated DNA regulatory elements and the coordinated function of a cascade of transcriptional regulators. We will test this hypothesis in two Specific Aims. Specific Aim 1: To define genome-wide the gene regulatory networks that control the emergence of early cardiac progenitors. We will define genome-wide regulatory networks that control the specification, migration, and differentiation of early cardiac precursor using transgenic reporter lines combined with single cell RNA-seq and single cell ATACseq (for chromatin accessibility) in normal and mutant embryonic heart development Specific Aim 2. To visualize the birth and migration of early cardiac progenitors with live embryo imaging. In this aim, we will use live embryo light sheet microscopic imaging of lineage-labeled mouse embryos to visualize in 4D the live dynamic emergence of cardiac progenitors, their migration, and their collective behaviours during early cardiac morphogenesis. We will further image in live embryos in 4D early cardiac progenitors in the context of impaired migration (Mesp1 knockout embryos) and defective differentiation of first or second heart fields (Tbx5 and Mef2c knockout embryos). From transcription factor footprints in the genome, to transcriptomes, to live cells in vivo, our project will elucidate at the single cell level the molecular nature of the earliest cardiac precursors.

概括哺乳动物心脏在胚胎发生的早期就形成了，其形成过程中的缺陷是先天性心脏病的根源。心脏缺陷 (CHD)，影响 1-2% 的活产儿 CHD 中受到干扰的基因调控网络。大规模人类遗传学研究已开始阐明许多导致冠心病的基因。转录调节因子，其中一些也与成人心脏病的遗传学有关，例如心肌病和心律失常。完整了解心脏祖细胞的诞生和第一步。导致胚胎心脏形成的基因对冠心病和成人心脏病都有影响。心脏在胚胎发生中的起源被定义为从中胚层开始，在我们之前定义了 Smarcd3 的一个特定增强子，它标记了一个非常有限的亚群。 Mesp1谱系标记的中胚层几乎只对心脏的胚胎发生有高度影响。动态过程，通过复杂的协调细胞运动定位器官前体以进行精确的定位形态发生，并控制对有效形态发生信号梯度的响应。心脏形态发生已在禽类胚胎中显现出来，这是我们对心脏祖细胞的了解缺乏小鼠胚胎的出现和行为，我们已经能够对活体谱系进行培养和成像。标记的小鼠胚胎，并将利用这种令人兴奋的方法来研究哺乳动物的心脏发育。我们追求早期心脏的分化、迁移和对早期心脏形成的贡献。祖细胞受到由时间调控 DNA 组成的特定基因调控网络的调控我们将测试这一点。假设有两个具体目标。具体目标 1：定义全基因组范围内控制早期细胞出现的基因调控网络我们将定义控制规范、迁移的全基因组调控网络。使用转基因报告系结合单细胞RNA-seq对早期心脏前体进行分化和分化正常和突变胚胎心脏发育中的单细胞 ATACseq（用于染色质可及性）具体目标 2. 通过活体胚胎成像来可视化早期心脏祖细胞的诞生和迁移。为此，我们将使用谱系标记的小鼠胚胎的活胚胎光片显微成像来以 4D 形式可视化心脏祖细胞的实时动态出现、它们的迁移以及它们的集体行为在早期心脏形态发生过程中，我们将进一步对 4D 早期心脏祖细胞的活胚胎进行成像。迁移受损（Mesp1 敲除胚胎）和第一或第二心脏分化缺陷的背景田（Tbx5 和 Mef2c 敲除胚胎）。从基因组中的转录因子足迹，到转录组，再到体内活细胞，我们的项目将阐明在单细胞水平上最早的心脏前体的分子性质。