Decoding regulatory nodes controlling growth and proportion of the skull

解码控制头骨生长和比例的调节节点

基本信息

批准号：
9906430
负责人：
Katherine Christine Woronowicz
金额：
$ 6.61万
依托单位：
BOSTON CHILDREN'S HOSPITAL
依托单位国家：
美国
项目类别：
财政年份：
2020
资助国家：
美国
起止时间：
2020-03-01 至 2023-02-28
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9906430
关键词：
Address Adult Affect Anterior Articulation Base Pairing Binding Brain Branchial arch structure CRISPR/Cas technology Cartilage Cell Differentiation process Cephalic Cleft Palate Clinical Code Complex Congenital Abnormality Craniofacial Abnormalities Data Development Disease Elements Embryo Enhancers Essential Genes Event Evolution Face Fertilization First Pharyngeal Arch Fishes Fluorescent in Situ Hybridization Gene Expression Gene Expression Regulation Genes Genetic Enhancer Element Genomic approach Genotype Growth Head Homeobox Homeobox Genes Hour Human Human Development Introns Jaw Knowledge Light Limb Bud Link Mastication Mediating Midbrain structure Modification Morphogenesis Morphology Mus Mutation Neural Crest Neural Crest Cell Neural Fold Nucleic Acid Regulatory Sequences Oral cavity Oropharyngeal Outcome Measure Pan Genus Pattern Phenotype Play Primates Prognathism Regulation Regulator Genes Regulatory Element Reporter Research Rest Role Sense Organs Signal Transduction Site Syndrome Synteny Testing Tissues Untranslated RNA Variant Vertebrates Work Zebrafish base bone cell motility comparative genomics craniofacial craniofacial complex craniofacial development craniofacial microsomia craniofacial structure cranium experimental study hindbrain improved in vivo loss of function mutant neurodevelopment novel preservation pressure single molecule spatiotemporal trait

项目摘要

PROJECT SUMMARY The skull is comprised of bones of different embryonic origins that articulate to encase the brain, to protect the sense organs, and to enable mastication. Well-orchestrated signaling and morphological events generate the seamless morphology of the craniofacial complex. Of central importance are the cranial neural crest cells (CNCCs) that migrate from the anterior neural folds to populate the oropharyngeal arches. CNCCs acquire axial identity from midbrain and hindbrain segmentation. Modifications to gene expression of CNCCs, their precursors, their derivatives, or even interacting tissues may underlie both normal variation and common craniofacial malformations. Although the gene regulatory networks that govern early specification of CNCCs are well known, we still lack detailed knowledge of later developmental events involving CNCC derivatives and how this relates to fundamental mechanisms of disease. The experiments outlined in this proposal will tease apart the morphological consequences of genotype. We expect that loci modifying the relative proportions of the skull and face will have commonalities amongst jawed vertebrates, as the head is an ancestral trait. Our prior phylogenomic comparisons identified fixed loci correlated with differential developmental prognathism. One of the regions identified encompasses a locus containing a large, cis-regulatory region highly conserved in all jawed vertebrates. This locus rests in an intron of agap1, and has retained directional synteny with the nearest neighbor, homeobox gene gbx2, over all of vertebrate evolution. This 343 base pair (bp) region is defined as having over 90% identity among vertebrates. A core of over 190bp is retained with 100% identity among primates, suggesting deep conservation preserved by strong selective pressure and a potential role in human development. Preliminary analyses suggest the region may participate in a broader regulatory hub that modulates expression of gbx2. As gbx2 is essential for patterning CNCCs, and is expressed in the oropharyngeal arches, my hypothesis is that the conserved non-coding region we identified acts as a specific enhancer for gbx2, mediating patterning of the forming arches and leading to proportional changes in outgrowth of the jaws. I will test this hypothesis by determining the function of components of the regulatory hub and their contributions to proper growth and form of the jaws. I will analyze necessity and function of orthologous sequences from zebrafish, chimp, and human, as well as determine the role of gbx2 in craniofacial morphology. Outcome measures include long-term assessment of CNCC migration and differentiation in vivo, and evaluating changes to spatiotemporal expression of gbx2 and related homeobox dlx genes in CNCCs and their derivatives. Findings from these experiments will lead to improved clinical strategies addressing disorders with disruptions to growth and form of the jaws as well as shed light on the contribution of coding and non-coding elements to craniofacial development and malformations.

项目摘要颅骨由表达以包围大脑的不同胚胎起源的骨骼组成，以保护感官器官，并实现咀嚼。经过精心修整的信号传导和形态事件产生颅面复合物的无缝形态。至关重要的是颅神经rest细胞（CNCC）从前神经褶皱迁移以填充口咽弓。 CNCC收购中脑和后脑分割的轴向身份。修改CNCC的基因表达，它们前体，它们的衍生物甚至相互作用的组织可能是正常变异和常见的基础颅面畸形。尽管控制CNCC早期规范的基因调节网络众所周知，我们仍然缺乏有关以后涉及CNCC衍生品和的后期发展事件的详细知识这与疾病的基本机制有关。该提案中概述的实验将取笑除了基因型的形态后果。我们希望基因座修改相对比例头骨和脸部将在颌脊椎动物中具有共同点，因为头部是祖先的特征。我们的先前的系统基因比较鉴定出固定基因座与差异发育预后相关。其中一个区域之一包括一个含有大型，顺式调节区域的基因座所有颌脊椎动物。该基因座位于AGAP1的内含子中，并保留了与在所有脊椎动物进化中，最近的邻居，同源基因GBX2。这个343个基对（BP）区域是定义为在脊椎动物中具有超过90％的身份。以100％的身份保留了超过190bp的核心在灵长类人类发展。初步分析表明，该地区可能会参与更广泛的监管枢纽调节GBX2的表达。由于GBX2对于对CNCC进行构图至关重要，并且在口咽弓，我的假设是我们确定的保守的非编码区域是一个 GBX2的特定增强子，介导形成拱门的模式，并导致比例下颌的产物变化。我将通过确定该假设来确定该假设的功能监管枢纽及其对颌骨的适当生长和形式的贡献。我将分析必要性斑马鱼，黑猩猩和人的直系同源序列的功能，并确定GBX2在颅面形态。结果措施包括对CNCC迁移的长期评估和体内分化，并评估GBX2和相关同源型DLX的时空表达的变化 CNCC及其衍生物中的基因。这些实验的发现将改善临床策略解决与生长和下颌形式中断的疾病，并阐明颅面发育和畸形的编码和非编码元素。