Regulation of Fibronectin expression in the neural crest during vascular morphogenesis

血管形态发生过程中神经嵴中纤连蛋白表达的调节

• 批准号: 9907526
• 负责人: Brianna Alexander
• 金额: $ 3.97万
• 依托单位: RBHS-NEW JERSEY MEDICAL SCHOOL
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-04-01 至 2023-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9907526
• 关键词: Ablation; Address; Affect; Apoptosis; Arteries; Attenuated; Birth; Blood; Blood Vessels; Blood flow; Branchial arch structure; Cardiac; Cell Differentiation process; Cell Lineage; Cell physiology; Cells; Congenital Abnormality; Data; Defect; Development; Developmental Process; Embryo; Embryonic Development; Endothelium; Ensure; Etiology; Exhibits; Extracellular Matrix; Extracellular Matrix Proteins; Family; Family member; Fibronectins; Genetic; Glycoproteins; Goals; Heart; Human; Hypoplastic Left Heart Syndrome; Impairment; Injections; Investigation; Left; Mediating; Messenger RNA; Morphogenesis; Motivation; Mouse Strains; Mus; Nature; Neural Crest; Neural Crest Cell; Neural tube; Newborn Infant; Operative Surgical Procedures; Pathway interactions; Pattern; Phenotype; Play; Population; Process; Production; Proteins; Regulation; Reproducibility; Research; Role; Route; Severities; Signal Transduction; Signaling Molecule; Smooth Muscle Myocytes; System; Tamoxifen; Testing; Transforming Growth Factor beta; United States; Vascular Smooth Muscle; aortic arch; cardiogenesis; cell type; congenital heart disorder; experience; experimental study; improved; intraperitoneal; mRNA Expression; mechanical force; protein expression; response; spatiotemporal; stem-like cell; tool

7. PROJECT ABSTRACT Congenital heart disease (CHD) is the most common human birth defect, with approximately 40,000 newborns affected annually in the United States. CHD is characterized by any defect in the formation of the heart and is often most severe when involving defects of the aortic arch artery (AAA) vasculature. The AAAs route oxygenated blood from the heart throughout the body and are formed from the remodeling of three pairs of pharyngeal arch arteries (PAAs), namely the 3rd, 4th and 6th. PAA-to-AAA remodeling depends upon a population of stem-like cells known as cardiac neural crest cells (cNCCs), and their differentiation to vascular smooth muscle cells (vSMCs) in the PAAs. Defective cNCC-to-vSMC differentiation results in AAA abnormalities including interrupted aortic arch, a severe defect of the 4th PAA which necessitates surgery upon birth. The extreme nature of arch artery defects resulting from defective cNCC-to-vSMC differentiation presents the need to investigate normal processes of cNCC-to-vSMC differentiation with a particular focus on the sensitivity of the 4th PAA to defects. Our lab previously found that the extracellular matrix protein, Fibronectin (Fn1), is essential for the process of cNCC-to-vSMC differentiation. Fn1 is expressed in cNCCs along a spatiotemporal gradient in murine pharyngeal arches. At E9.5, its expression is detected in migrating cNCCs; but by E10.5, when cNCCs are filling the PAAs, its expression is attenuated. By E11.5, just prior to cNCC-to-vSMC differentiation, its expression is restored in such a manner that cNCCs closest to the PAA lumen exhibit the highest expression while those farther away exhibit less, phenocopying the pattern of cNCC-to-vSMC differentiation. Ablation of Fn1, specifically in cNCCs, results in attenuated vSMC differentiation and defective PAA-to-AAA remodeling. This phenotype is not rescued by exogenous Fn1 or the presence of other matrix proteins, indicating the cell-autonomous function of Fn1 in cNCCs. As critical as Fn1 is in cNCC-to-vSMC differentiation and downstream PAA-to-AAA remodeling, how its expression is regulated in cNCCs is unknown. We hypothesize that the induction of Fn1 within cNCCs is initiated by blood-flow induced TGFβ signaling in cNCCs or the endothelium. We propose to investigate the role of the TGFβ superfamily (via Smad4) in regulating Fn1 in cNCCs for various reasons: (1) The role that the TGFβ family plays in regulating Fn1 during embryogenesis is not well understood (2) TGFβ is a mechanoresponsive pathway which may regulate the spatiotemporal gradient of Fn1 in response to blood flow (3) there is controversy over the role of TGFβ in cNCC development and (4) there are improved genetic tools which will allow us to investigate TGFβ signaling in our system. Our preliminary data suggests that Smad4 is important for cNCC-specific Fn1 production in the pharyngeal arches, yet we do not know the cell type in which Smad4 must function for this response. We propose to address the role of Smad4 in a cell-type specific manner with the experiments outlined in this F31 application (see Research Strategy). Completion of the experiments outlined in this proposal will help to elucidate factors which may contribute to the etiology of arch-artery CHDs.

7。项目摘要 先天性心脏病（CHD）是最常见的人类出生缺陷，大约有40,000名新生儿 每年在美国受到影响。 CHD的特征是心脏形成中的任何缺陷，是 当涉及主动脉弓动脉（AAA）脉管系统缺陷时，通常最严重。 AAAS路线 整个身体的心脏充氧血液，由三对的重塑形成 咽弓动脉（PAAS），即第三，第四和第六。 PAA到AAA的重塑取决于人口 干细胞称为心脏神经元细胞（CNCC），它们与血管平滑肌的分化 PAAS中的细胞（VSMC）。 CNCC到VSMC的有缺陷导致AAA异常，包括 中断主动脉弓，这是第四个PAA的严重缺陷，该缺陷在出生时必要手术。极端性质 CNCC至VSMC分化缺陷导致的拱门动脉缺陷表明需要调查 CNCC至VSMC分化的正常过程，特别关注第四PAA的灵敏度 缺陷。我们的实验室以前发现，细胞外基质蛋白纤连蛋白（FN1）对于 FN1沿着鼠的时空梯度在CNCC中表达 咽弓。在E9.5，在迁移的CNCC中检测到其表达。但是到E10.5，当CNCC填充时 Paas，其表达被减弱。到e11.5，在CNCC-至VSMC分化之前，其表达是 恢复的方式使CNCC最接近PAA管腔暴露了最高表达，而这些表达式 较远的暴露较少，表现为CNCC-to-VSMC分化的模式。 FN1的消融 在CNCC中，导致VSMC分化和PAA-TO-AAA重塑有缺陷的结果。这种表型是 不反应外源FN1或其他基质蛋白的存在，表明细胞自主功能 CNCC中的FN1。在CNCC-to-vsmc差异和下游PAA-to-aaA重塑中，同样重要的是 其在CNCC中如何调节其表达尚不清楚。我们假设CNCC中FN1的诱导 由血流引起的CNCC或内皮诱导的TGFβ信号传导引发。我们建议调查 由于各种原因 在胚胎发生过程中调节FN1的TGFβ家族尚不清楚（2）TGFβ是A 机械响应途径可能会根据血流来调节FN1的时空梯度 （3）关于TGFβ在CNCC发育中的作用存在争议，（4）有改善的遗传工具 这将使我们能够研究系统中的TGFβ信号传导。我们的初步数据表明Smad4是 对于咽弓中的CNCC特异性FN1产生很重要，但我们不知道细胞类型 SMAD4必须为此响应起作用。我们建议以细胞类型的方式解决SMAD4的作用 通过在此F31应用中概述的实验（请参阅研究策略）。实验完成 该提案中概述的将有助于阐明可能有助于Arter-Arty Chd的病因的因素。