Cellular and Genetic Determinants of Pharyngeal Arch Artery Specification

咽弓动脉规格的细胞和遗传决定因素

• 批准号: 8526115
• 负责人: Noelle Nicole Paffett-Lugassy
• 金额: $ 5.77万
• 依托单位: MASSACHUSETTS GENERAL HOSPITAL
• 依托单位国家: 美国
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-07-01 至 2014-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8526115
• 关键词: Angioblast; Animal Model; Anterior; Arteries; Binding Proteins; Biology; Birth; Blood; Blood Vessels; Branchial arch structure; Burn injury; Cardiac; Cardiovascular system; Cells; Cephalic; Complex; Congenital Disorders; Coronary artery; Data; Defect; Development; Diagnostic; Dissection; Embryo; Embryonic Development; Endothelium; Evaluation; First Pharyngeal Arch; Fluorescence; Genes; Genetic; Genetic Determinism; Genetic Programming; Genetic Screening; Goals; Heart; Human; Hypoplastic Left Heart Syndrome; Imagery; Investigation; Island; Laboratories; Lasers; Lateral; Lead; Life; Location; Maps; Mediating; Mesoderm; Molecular; Mus; Mutation; Outcome; Pathway interactions; Pattern; Play; Population; Positioning Attribute; Reagent; Reporter; Role; Signal Transduction; Source; Specific qualifier value; Testing; Therapeutic; Time; Transcript; Transforming Growth Factor beta; Zebrafish; base; chemical genetics; human disease; improved; malformation; novel; novel marker; progenitor; programs; public health relevance; transcription factor

DESCRIPTION (provided by applicant): Malformations involving the large arteries that exit the heart (e.g. "the great vessels") are common congenital disorders. In most circumstances, the genetic basis for these abnormalities has not been identified. During embryogenesis, the great vessels arise from six pairs of bilaterally symmetric arteries embedded within the pharyngeal arches that undergo extensive remodeling to produce the complex pattern present at birth. Although the remodeling aspects have been extensively studied, the developmental origin of pharyngeal arch arteries (PAAs) and the genetic programs regulating their specification remain elusive. As severe great vessel defects are incompatible with life and milder deficiencies cause congenital cardiovascular malformations (CCMs), our long-term goal is to elucidate the cellular source of PAA endothelium and to identify genetic pathways mediating PAA establishment to potentially identify novel human disease genes. The zebrafish model organism allows for unparalleled real-time visualization and genetic dissection of PAA development. Through examination of a novel Tg(nkx2.5:ZsYellow) zebrafish reporter line, I unexpectedly discovered ZsYellow fluorescence in PAA endothelium. This observation was not anticipated, as nkx2.5 transcripts are not observed in this population. Based on these data, I postulate that PAA endothelium derives from an earlier nkx2.5+ cellular source in which ZsYellow fluorescence has persisted. Although completely unexplored, this hypothesis is supported by traditional nkx2.5 cre/loxP lineage tracing in mice. Thus, it is likely that nkx2.5 plays a conserved, yet heretofore unrecognized, role in great vessel establishment that warrants further investigation. My preliminary data also demonstrate that nkx2.5 and a requisite TGFbeta pathway component, Latent TGFbeta Binding Protein 3 (ltbp3), are required for PAA development, but dispensable for induction of the remaining vasculature. Based on compelling preliminary data, I propose to test the hypothesis that ltbp3-mediated TGFbeta signaling from the second heart field (SHF) promotes endothelial differentiation of nkx2.5-expressing PAA progenitors. Having developed new reagents for illuminating nkx2.5+ progenitors and their derivatives, I have the unique opportunity to directly test this idea. As PAA defects cause CCMs or embryonic lethality, the proposed studies are significant for informing the development of improved preventative and therapeutic approaches.

描述（由申请人提供）：涉及离开心脏的大动脉（例如“大血管”）的畸形是常见的先天性疾病。在大多数情况下，这些异常的遗传基础尚未确定。在胚胎发生过程中，大血管由嵌入咽弓内的六对双边对称动脉产生，这些动脉经历了广泛的重塑，以产生出生时出现的复杂模式。尽管重塑方面已被广泛研究，但咽弓动脉（PAA）的发育起源和调节其规格的遗传程序仍然难以捉摸。由于严重的大血管缺陷与生命不相容，而较轻微的缺陷会导致先天性心血管畸形 (CCM)，因此我们的长期目标是阐明 PAA 内皮的细胞来源，并确定介导 PAA 建立的遗传途径，以潜在地识别新的人类疾病基因。斑马鱼模型生物可以对 PAA 发育进行无与伦比的实时可视化和遗传解剖。通过检查新的Tg(nkx2.5:ZsYellow)斑马鱼报告线，我意外地在PAA内皮细胞中发现了ZsYellow荧光。这一观察结果是出乎意料的，因为在该群体中没有观察到 nkx2.5 转录本。根据这些数据，我推测 PAA 内皮源自早期的 nkx2.5+ 细胞来源，其中 ZsYellow 荧光一直持续存在。尽管尚未完全探索，但这一假设得到了小鼠中传统 nkx2.5 cre/loxP 谱系追踪的支持。因此，nkx2.5 很可能在大血管的形成中发挥着保守但迄今为止未被认识的作用，值得进一步研究。我的初步数据还表明，nkx2.5 和必需的 TGFbeta 途径成分、潜在 TGFbeta 结合蛋白 3 (ltbp3) 是 PAA 发育所必需的，但对于剩余脉管系统的诱导是可有可无的。基于令人信服的初步数据，我建议检验以下假设：来自第二心区 (SHF) 的 ltbp3 介导的 TGFbeta 信号传导促进表达 nkx2.5 的 PAA 祖细胞的内皮分化。在开发出用于照亮 nkx2.5+ 祖细胞及其衍生物的新试剂后，我有独特的机会直接测试这个想法。由于 PAA 缺陷会导致 CCM 或胚胎致死，因此拟议的研究对于改进预防和治疗方法的开发具有重要意义。