Modeling conotruncal malformations in zebrafish embryos

斑马鱼胚胎圆锥干畸形的建模

• 批准号: 7745508
• 负责人: Margaret Loewy Kirby
• 金额: $ 41.5万
• 依托单位: DUKE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-01-01 至 2011-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7745508
• 关键词: Ablation; Affect; Animal Model; Animals; Arteries; Blood Circulation; Breeding; Candidate Disease Gene; Cardiac; Cell Death; Cell Lineage; Cell physiology; Cells; Characteristics; Congenital Abnormality; Congenital Heart Defects; Defect; Development; Developmental Process; Distal; Double Outlet Right Ventricle; Elements; Embryo; Epiblast; Event; FGF8 gene; Gene Mutation; Gene-Modified; Genes; Genetic; Genetic Models; Genetic Screening; Growth Factor; Heart; Heterozygote; Individual; Knowledge; Label; Laminin; Life; Lung; Maps; Modeling; Molecular; Mothers; Mutation; Myocardial; Myocardium; Neural Crest; Neural Crest Cell; Oligonucleotides; Organism; Patients; Persistent Truncus Arteriosus; Phenocopy; Phenotype; Population; Process; Reagent; Recording of previous events; Recruitment Activity; Reporting; Research Personnel; Risk; Role; Screening procedure; Signal Transduction; Site; Smooth Muscle; Smooth Muscle Myocytes; Staining method; Stains; Technology; Testing; Tetralogy of Fallot; Time; Tunic; Work; Zebrafish; base; blastomere structure; cardiogenesis; cell type; design; gene discovery; high throughput screening; malformation; migration; muscle form; mutant; null mutation; offspring; progenitor; programs; research study

DESCRIPTION (provided by applicant): Abnormal development of the myocardial-smooth muscle junction at the arterial pole of the heart leads to congenital defects classified as conotruncal malformations such as double outlet right ventricle and tetralogy of Fallot. Recent work from our lab shows that the basic elements that build the arterial pole prior to septation are highly conserved during development. In development of a heart with divided pulmonary and systemic circulations, the myocardium and smooth muscle are added to the arterial pole long before the region is septated. Further work from this lab has shown definitively that arterial pole malalignments, i.e. conotruncal malalignment defects are due to abnormal pre-septation arterial pole development. The zebrafish is an ideal organism in which to study arterial pole development without the confounding event of septation. In addition, its strength as a genetic model makes it an excellent vertebrate in which to study genes that potentially underlie conotruncal malformations. Tbx1 is a gene associated with the DiGeorge phenotype of which conotruncal malformations are a major component. The zebrafish van gogh mutant has a null mutation in tbxl, but the heart defect associated with this mutation has never been analyzed for arterial pole development. In addition, FGF8 is reported to be a downstream effecter of TBX1 and we have evidence in the chick that outflow alignment is very sensitive to FGF8 signaling. Thus, the hypothesis for this proposal is that Tbx1 through FGF8 and other as yet unidentified genes regulates the contribution of precursors to the myocardial and smooth muscle cells that form the arterial pole of the zebrafish heart. To understand the gene-phenotype relationship of conotruncal malformations we need to have detailed information about the origin and developmental history of the arterial pole progenitors. Therefore, Aim 1 will use cell tracing and ablations to identify and determine the contribution of the progenitors of the myocardium and smooth muscle that form the zebrafish arterial pole. The type of cell tracing and discrete ablations of the arterial pole progenitors that are proposed are not possible in any other animal model. Aim 2 will determine the sensitivity of these progenitors in forming the arterial pole to disrupted expression of tbxl and fgf8 using zebrafish mutants and antisense morpholino technology. These experiments will provide cellular and molecular information about normal and abnormal development of the arterial pole progenitors in a genetic background similar to that in DiGeorge patients. Because of the variability of the DiGeorge phenotype Aim 3 is designed to identify unknown genetic modifiers of tbxl function using a candidate gene approach and high throughput screening of double heterozygotes. Because the arterial pole is the site of conotruncal malformations, detailed knowledge of its development and the genes that influence it will ultimately allow better prediction of individuals at risk for having offspring with such malformations.

描述（由申请人提供）：心脏动脉极的心肌平滑肌肉结的异常发育导致先天性缺陷分类为构成骨畸形的畸形，例如双出出出来的右心室和Fallot的四部曲。我们实验室的最新工作表明，在开发过程中，在分隔之前建立动脉极的基本要素是高度保守的。在具有分裂的肺部和全身循环的心脏的发育中，在该区域被分解之前，心肌和平滑肌被添加到动脉极。该实验实验室的进一步工作确定表明，动脉极不符，即共骨畸形缺陷是由于异常的细胞前动脉发育引起的。斑马鱼是一种理想的生物体，可以在不混杂的情况下研究动脉发育。此外，它作为遗传模型的强度使其成为一种出色的脊椎动物，在其中研究可能是构成构畸形的基因。 TBX1是与Digeorge表型相关的基因，该基因是共鸣畸形是主要组成部分的基因。斑马鱼Van Gogh突变体在TBXL中的突变无效，但是与该突变相关的心脏缺陷从未被分析用于动脉极发育。此外，据报道，FGF8是TBX1的下游效应元素，我们在小鸡中有证据表明流出比对非常敏感FGF8信号传导。因此，该提议的假设是TBX1通过FGF8和其他尚未确定的基因调节前体对形成斑马鱼心动脉极的心肌和平滑肌细胞的贡献。为了了解综合畸形的基因 - 表型关系，我们需要拥有有关动脉极端祖细胞的起源和发育历史的详细信息。因此，AIM 1将使用细胞追踪和消融来识别和确定形成斑马鱼动脉极的心肌和平滑肌祖细胞的贡献。在任何其他动物模型中，都不可能使用所提出的动脉极祖细胞的细胞追踪和离散消融。 AIM 2将确定这些祖细胞在形成动脉极使用斑马鱼突变体和反义morpholino技术中破坏TBXL和FGF8表达的敏感性。这些实验将提供有关在遗传背景下类似于Digeorge患者的遗传背景下动脉极祖细胞正常和异常发育的细胞和分子信息。由于Digeorge表型的可变性，AIM 3旨在使用候选基因方法和双重杂合子的高吞吐量筛选来识别TBXL功能的未知遗传修饰符。由于动脉极是构成畸形的部位，因此对其发育的详细知识及其影响其影响的基因最终将使对具有这种畸形后代的风险的个人更好地预测。