Molecular and cellular mechanisms in cardiac outflow tract formation and defects

心脏流出道形成和缺陷的分子和细胞机制

• 批准号: 10289982
• 负责人: BERNICE E MORROW
• 金额: $ 66.36万
• 依托单位: ALBERT EINSTEIN COLLEGE OF MEDICINE
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-09-01 至 2025-08-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10289982
• 关键词: 22q11; 22q11.2; 3-Dimensional; Affect; Biological Assay; Cardiac; Cell Communication; Cell Lineage; Cells; Clinical; Code; Defect; Development; Developmental Biology; DiGeorge Syndrome; Disease; Distal; Embryo; Endocardium; Endothelin-1; Ensure; Genes; Genetic; Heart; Heart Septum; Histology; Human; Immunofluorescence Immunologic; In Situ Hybridization; Intervention; Knowledge; Live Birth; Medical; Mesenchymal; Modeling; Molecular; Morphogenesis; Mus; Mutation; NOTCH1 gene; Neural Crest; Neural Crest Cell; Neural tube; Neurophysiology - biologic function; Newborn Infant; Outcome; Patients; Pattern; Persistent Truncus Arteriosus; Phenotype; Population; Positioning Attribute; Prevalence; Process; Proteins; Pulmonary Circulation; Research Project Grants; Role; Signal Transduction; Structural defect; Structure; Syndrome; Testing; Tetralogy of Fallot; Tissues; Validation; Ventricular Septal Defects; Ventricular septum; base; bicuspid aortic valve; cardiogenesis; congenital heart disorder; connective tissue growth factor; experimental study; genetic signature; genetic variant; in vivo; malformation; mouse model; mutant; programs; reconstruction; restoration; semilunar valve; single-cell RNA sequencing; stem cell function; stem cells

Project Summary Cardiac outflow tract (OFT) defects have an estimated prevalence of 1-2 in 1,000 live births. The 22q11.2 deletion syndrome or 22q11.2DS is one of the most frequent genetic causes of cardiac OFT defects. A total of 60% of patients with 22q11.2DS have congenital heart disease that ranges from mild to severe including bicuspid aortic valve (BAV), isolated ventricular septal defects (VSDs) to tetralogy of Fallot (TOF) or persistent truncus arteriosus (PTA). These clinical findings suggest genetic modifiers may affect phenotypic expression . In this project, we propose to use the Lgdel/+ mouse model to understand the relationship between neural crest cells (NCCs) and adjacent endocardial cells (ECCs) in forming and remodeling of the cardiac OFT. Mesenchymal cells (MCs) derived from NCCs and ECCs occupy the distal and proximal OFT, respectively, and form a distinct OFT MC boundary during heart development. Proper deployment of MCs from the two lineages ensures correct position and formation of aorto-pulmonary-ventricular septum and semilunar valves to separate the heart outlet into the systemic and pulmonary circulation. The function of NCCs in OFT defects has been well studied with respect to 22q11.2DS, however, the role of ECCs in OFT malformations has not been investigated. We have begun to fill this knowledge gap by studying the Lgdel/+ mouse, which was generated by deleting one copy of the mouse syntenic region of human 22q11.2 containing 26 protein-coding genes (22q11.2DS genes). We found a spectrum of OFT defects ranging from isolated VSD to TOF. The structural defects are preceded by a disrupted OFT MC boundary, increased expression of Edn1 during endocardial-to-mesenchymal transformation (EMT), and decreased NOTCH1 signaling and Ctgf expression during post-EMT OFT remodeling. By single cell RNA sequencing (scRNA-seq), we identified Edn1 as part of a unique gene program operating in a subset of ECCs undergoing EMT. Based on these findings, we propose an overall hypothesis that 22q11.2DS genes control OFT development by regulating the function of ECCs and the cell-cell communications between MCs from ECC and NCC origins, via interacting with genes essential for OFT formation. We will test this hypothesis in three specific aims. Aim 1 will determine whether the 22q11.2DS genes regulate EMT through modulating the EMT gene program, and if Edn1 acts downstream of 22q11.2DS genes to regulate the process. Aim 2 will ascertain whether 22q11.2DS genes also regulate OFT remodeling through a cell-cell interaction network that patterns the OFT MC boundary, and if Ctgf functions as a hub gene required for the post-EMT OFT remodeling, downstream of 22q11.2DS genes. Aim 3 will define whether Notch1 haploinsufficiency can potentiate the 22q11.2DS OFT defects. At the completion of this study, we expect discoveries that will establish genetic, molecular, and cell crosstalk regulated by important syndromic and non-syndromic CHD genes essential for mouse OFT morphogenesis. The information will provide deeper understanding of heart developmental biology and inform the disease mechanism of OFT defects, with a broader implication in congenital heart disease.

项目摘要 心脏流出路（通常）缺陷估计患病率为1,000个活产。这 22Q11.2缺失综合征或22q11.2ds是心脏oft缺陷最常见的遗传原因之一。一个 共有60％的22q11.2d患者患有先天性心脏病，范围从轻度到重度，包括 双质主动脉瓣（BAV），孤立的心室间隔缺陷（VSD）到法洛（TOF）或持续的四边形 Truncus Arteriosus（PTA）。这些临床发现表明遗传修饰剂可能会影响表型表达 。在 这个项目，我们建议使用LGDEL/+鼠标模型来了解神经Crest之间的关系 细胞（NCC）和邻近的心内膜细胞（ECC）形成和重塑心脏OFT。 来自NCC和ECC的间充质细胞（MC）分别占据远端和近端OFT，并且 在心脏发育过程中形成一个独特的MC边界。从两个谱系中正确部署MC 确保主动脉 - 肺室中隔膜和半肺瓣的正确位置和形成 心脏出口进入全身和肺循环。 NCC在通常的缺陷中的功能很好 但是，研究了22q11.2ds的研究，尚未研究ECC在FEST畸形中的作用。 我们已经开始通过研究LGDEL/+鼠标来填补这一知识差距 人类22q11.2的小鼠同义区域的副本，其中包含26个蛋白质编码基因（22q11.2ds基因）。 我们发现了从孤立的VSD到TOF的经常缺陷。结构缺陷之前 破坏的Oft MC边界，心内膜到 - especlymal期间EDN1的表达增加 转化（EMT），并在EMT重塑后重塑期间降低Notch1信号传导和CTGF表达。 通过单细胞RNA测序（SCRNA-SEQ），我们将EDN1确定为在运行中的独特基因程序的一部分 EMT的一个子集。基于这些发现，我们提出了一个总体假设，即22q11.2ds 基因通过调节ECC的功能和细胞电池通信来控制开发的基因开发 来自ECC和NCC起源的MC通过与FOST形成必不可少的基因相互作用。我们将测试这个 三个特定目标的假设。 AIM 1将确定22q11.2dst基因是否通过 调节EMT基因程序，如果EDN1在22q11.2ds基因的下游作用以调节过程。 AIM 2将确定22q11.2ds基因是否也通过细胞 - 细胞相互作用调节重塑 模式的网络，且CTGF充当后EMT所需的集线器基因 重塑，下游22q11.2ds基因。 AIM 3将定义Notch1单倍不足是否可以 增强22q11.2d oft缺陷。这项研究完成后，我们希望发现会建立 由重要综合征和非综合症CHD基因调节的遗传，分子和细胞串扰必不可少的 用于小鼠的形态发生。该信息将为心脏发展提供更深入的了解 生物学并告知FAST缺陷的疾病机制，对先天性心脏有更广泛的影响 疾病。