Sonic Hedgehog Signaling in Zebrafish Branchial Arch Development

斑马鱼鳃弓发育中的声波刺猬信号

• 批准号: 7614834
• 负责人: Tyler Schwend
• 金额: $ 2.84万
• 依托单位: LURIE CHILDREN'S HOSPITAL OF CHICAGO
• 依托单位国家: 美国
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-09-16 至 2010-09-15
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7614834
• 关键词: Address; Biological Availability; Biological Models; Brain; Branchial arch structure; Cartilage; Cell Transplantation; Cells; Cephalic; Childhood; Chondrogenesis; Color; Confocal Microscopy; Congenital Abnormality; Craniofacial Abnormalities; Defect; Development; Developmental Process; Disease; Disruption; Elements; Embryo; Embryonic Development; Endoderm; Erinaceidae; Face; Failure; Generations; Genes; Genetic; Goals; Growth; Holoprosencephaly; Human; Individual; Investigation; Jellyfish; Lead; Ligands; Malignant neoplasm of brain; Microcephaly; Modeling; Molecular; Mutation; Oral; Pathway interactions; Patients; Pattern; Phenotype; Play; Protein Overexpression; Proteins; Range; Reporter; Research; Role; SHH gene; Signal Pathway; Signal Transduction; Signal Transduction Pathway; Skeletal Development; Skeletal system; Skeleton; Source; Techniques; Testing; Tissues; Transgenic Organisms; Work; Zebrafish; attenuation; base; burden of illness; cartilage development; chondrogenesis factor; cleft lip and palate; craniofacial; human SMO protein; in vivo; interest; morphogens; mutant; notochord; novel; precursor cell; receptor; research study; smoothened signaling pathway; transcription factor

DESCRIPTION (provided by applicant): The proposed studies seek to determine the cellular and molecular mechanisms of Shh signaling in the craniofacial skeleton. This may provide new explanations for the wide range of phenotypes observed in Holoprosencephaly patients. To examine the function of Shh in branchial arch development we analyzed the zebrafish chameleon (con) mutant, harboring a defective Displ protein, con mutant embryos lack all branchial arch cartilage, a defect that can be partially explained by a failure of the branchial arch precursors to maintain the essential chondrogenic transcription factor Sox9a. The proposed research will specifically seek to delineate the signaling mechanism whereby the Shh pathway promotes chondrogenesis in the branchial arches. We hypothesize that Displ acts within pharyngeal endoderm non cell autonomously to release Shh which directs branchial arch cartilage precursors toward chondrogenic differentiation. Utilizing cell transplantation studies, we will generate chimeric embryos to demonstrate the cell autonomy of Displ and Smo function. This will determine which cells in the craniofacial region must release (Displ) and respond (Smo) to the Shh ligand. Furthermore, our work has delineated multiple temporal requirements for Shh signaling in branchial arch development. Utilizing a well-characterized GN1 activity reporter construct, we will generate a novel transgenic zebrafish to precisely determine which cells recieve the Shh ligand and when this occurs during cartilage development. Lastly, human craniofacial diseases arise from the misregulation of the SHH pathway and SOX9, therefore further investigation of this potential regulatory relationship is of considerable interest. In vivo overexpression studies will be performed to assess whether ectopic SoxQa in the branchial arches can rescue inactivation of the Shh pathway. The Shh signal transduction pathway plays a central role in growth and patterning of the brain and face. Disruptions in this pathway during embryonic development lead to a considerable disease burden, most often classified as the spectral disorder Holoprosencephaly. The overall goal of this proposed research is to determine the cellular and molecular mechanism of the Shh pathway that controls craniofacial skeleton development.

描述（由申请人提供）：拟议的研究旨在确定颅面骨骼中Shh信号的细胞和分子机制。这可能为无前脑畸形患者广泛的表型观察提供新的解释。为了研究Shh在鳃弓发育中的功能，我们分析了斑马鱼变色龙（con）突变体，含有缺陷的Displ蛋白，con突变体胚胎缺乏所有的鳃弓软骨，这一缺陷可以部分解释为鳃弓前体无法维持必需的软骨转录因子Sox9a。拟议的研究将特别寻求描述Shh通路促进鳃弓软骨形成的信号机制。我们假设Displ在咽内胚层非细胞内自主释放Shh，引导鳃弓软骨前体向软骨分化。利用细胞移植研究，我们将产生嵌合胚胎来证明Displ和Smo功能的细胞自主性。这将决定颅面区域的哪些细胞必须对Shh配体释放（Displ）和应答（Smo）。此外，我们的工作已经描述了鳃弓发育中Shh信号的多重时间要求。利用表征良好的GN1活性报告结构，我们将产生一种新的转基因斑马鱼，以精确确定哪些细胞接受Shh配体以及在软骨发育过程中何时发生。最后，人类颅面疾病是由SHH通路和SOX9的错误调控引起的，因此进一步研究这种潜在的调控关系是相当有趣的。将进行体内过表达研究，以评估鳃弓中异位的SoxQa是否可以挽救Shh通路的失活。Shh信号转导通路在大脑和面部的生长和模式中起着核心作用。在胚胎发育过程中，这一通路的中断会导致相当大的疾病负担，最常被归类为谱系障碍前脑畸形。本研究的总体目标是确定Shh通路控制颅面骨骼发育的细胞和分子机制。