Testing the tissue-specific mechanisms of Hoxa5 function in musculoskeletal patterning

测试 Hoxa5 在肌肉骨骼模式中功能的组织特异性机制

• 批准号: 9351838
• 负责人: Jennifer H Mansfield
• 金额: $ 38.95万
• 依托单位: BARNARD COLLEGE
• 依托单位国家: 美国
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-09-09 至 2021-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9351838
• 关键词: Address; Alleles; Animals; Anterior; Arts; Behavior; Binding Sites; Body Patterning; Bone Development; Cartilage; Cell physiology; Cells; Cervical; Chest; Chondrocytes; Chromatin Structure; Congenital Abnormality; Connective Tissue; Connective Tissue Diseases; Dermis; Development; Disease; Dissection; Dissociation; Elements; Embryo; Endothelium; Epitopes; Flow Cytometry; Gene Targeting; Genes; Genetic; Genetic Transcription; Genomics; Genotype; Goals; HOX protein; Health; High-Throughput Nucleotide Sequencing; Homeobox Genes; Human; Label; Lead; Ligaments; Light; Maintenance; Malignant Neoplasms; Mammals; Maps; Mediating; Molecular; Molecular Genetics; Morphogenesis; Morphology; Mus; Muscle; Muscle Development; Musculoskeletal; Musculoskeletal Development; Mutation; Osteogenesis; Other Genetics; Pathway interactions; Pattern; Phenotype; Play; Positioning Attribute; Process; Proteins; Regulation; Research; Resources; Role; Sclerotome; Signal Transduction; Skeleton; Somites; Specific qualifier value; Specificity; Students; Tendon structure; Testing; Tissues; Training; Underrepresented Groups; Variant; Vertebral column; Vertebrates; Woman; Work; base; bone; cartilage development; chromatin immunoprecipitation; cofactor; college; design; differential expression; experimental study; genetic approach; in vivo; laboratory curriculum; ligament development; loss of function; polyclonal antibody; progressive myositis ossificans; rib bone structure; skeletal; skeletal tissue; student participation; tendon development; transcription factor; transcriptome sequencing; undergraduate student

Abstract Development of cartilage, bones, muscles, tendons and ligaments must be highly coordinated, with tissue type differentiation and morphogenesis occuring in a concerted way that allows the resulting tissues to function together. The axial musculoskeleton (vertebral column and ribs) develops from the somites, in which all musculoskeletal tissue types are specified and develop coordinately. However, the morphology of somite derivatives varies with position along the body axis. This variation is controlled by Hox proteins, conserved transcription factors that pattern the body axis of most animal embryos. In vertebrates, Hox proteins both confer anterior-posterior identity on nascent segments and play direct roles in tissue morphogenesis later in development. However, we still know relatively little about their mechanisms of action, including the cell and tissue types in which they act, the cellular behaviors they regulate, and ultimately their transcriptional targets. Hoxa5 non-redundantly patterns musculoskeletal elements at the cervical-thoracic transition. In order to understand how it acts, we used genetic lineage labeling to fate map the descendants of Hoxa5 expressing cells. We found that Hoxa5 descendants contribute to a restricted number tissue types, such as cartilage and perichondrium, but only contribute rarely to tendon and never to muscle. This restriction of Hoxa5 descendant fate may reflect an important aspect of its function. Here, we propose to investigate the mechanism through which Hoxa5 patterns the cervical-thoracic transition musculoskeleton of mice, using a combination of genetic lineage labeling, conditional and loss-of-function analysis, and high throughput sequencing. Our specific aims are designed to: (1) Identify the tissue specificity of Hoxa5 action in patterning the axial skeleton (2) Identify genes and gene networks regulated cell-autonomously by Hoxa5 and (3) Identify direct transcriptional targets of Hoxa5 in the somites. Successful completion of this project will shed light on the mechanisms through which axial patterning is regulated by Hox genes, and can also be applied to a general understanding the mechanisms of Hoxa5 in other tissue types and cancers. More generally, the work is relevant to human health through its application to understanding musculoskeletal tissue patterning and differentiation during normal development and disease. Finally, this work will be conducted with undergraduates at Barnard College, a liberal arts college for women. It will be performed by research students in the PI’s lab, and will be introduced into a newly developed, full year laboratory course at Barnard. Course-based research has been shown to increase participation of students, including those from underrepresented groups, in STEM and to increase the pursuit of postgraduate STEM training. This course will engage undergraduates in substantive original research while providing them with training in current molecular genetics approaches.

抽象的 软骨，骨骼，肌肉，肌腱和韧带的发展必须高度协调，并与 组织类型的分化和形态发生以一致的方式发生，使结果允许 组织起作用。轴向肌肉骨骼（椎骨和肋骨）从 在其中指定所有肌肉骨骼组织类型并协调发展的节。但是， 沿体轴的位置变化的体积衍生物的形态。这种变化由 HOX蛋白，配置了大多数动物胚胎的身体轴的转录因子。在 脊椎动物，HOX蛋白都会在新生段会议前后身份并进行直接发挥作用 后来在组织形态发生中的作用。但是，我们仍然对他们的了解很少 作用机理，包括其作用的细胞和组织类型，细胞行为 调节其转录目标。 HOXA5非额外模式肌肉骨骼 颈胸腔过渡的元素。为了了解其行为方式，我们使用了遗传谱系 标记以命运映射Hoxa5表达细胞的后代。我们发现Hoxa5后代 有限制的数量组织类型，例如软骨和perichondrium，但仅贡献 很少肌腱，永远不要肌肉。 Hoxa5后代命运的这种限制可能反映出一个重要的 其功能的方面。在这里，我们建议研究Hoxa5模式的机制 小鼠的颈胸腔过渡肌肉骨骼，结合遗传谱系标记， 条件和功能丧失分析以及高通量测序。我们的具体目标是 设计为：（1）确定HOXA5作用的组织特异性在对轴向骨架上图案时（2） 通过HOXA5识别基因和基因网络对细胞自动调节，（3）识别直接 Hoxa5的转录目标。成功完成该项目将阐明 轴向图案通过HOX基因调节的机制，也可以应用于A 一般了解Hoxa5在其他组织类型和癌症中的机制。更普遍的是 工作与人类健康有关，通过其应用来了解肌肉骨骼组织 正常发育和疾病期间的模式和分化。最后，这项工作将是 与女性文科学院巴纳德学院（Barnard College）一起与本科生一起举办。它将进行 由PI实验室的研究专业的研究生，将被引入新开发的全年实验室 巴纳德的课程。基于课程的研究已被证明增加了学生的参与， 包括来自代表性不足的群体的人，在STEM中并增加对研究生的追求 STEM培训。本课程将在提供实质性原始研究的本科生中。 他们接受了当前分子遗传学方法的训练。