CONTROL OF MUSCLE PROTEIN SYNTHESIS DURING MYOGENESIS

肌生成过程中肌肉蛋白合成的控制

• 批准号: 7867022
• 负责人: CHARLES P. EMERSON
• 金额: $ 1.18万
• 依托单位: BOSTON BIOMEDICAL RESEARCH INSTITUTE
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-06-01 至 2010-10-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7867022
• 关键词: Biological Assay; Birds; Cell Lineage; Cell surface; Cells; Cloning; Complementary DNA; Computer Analysis; Cultured Cells; Development; Disease; Electroporation; Embryo; Enhancers; Erinaceidae; Extracellular Matrix; Family; Fibroblast Growth Factor; Gene Expression; Gene Targeting; Genes; Genetic; Genetic Transcription; Homologous Gene; Investigation; Knowledge; Lead; Maintenance; Maps; Mediating; Molecular; Molecular Genetics; Mus; Muscle; Muscle Proteins; Myoblasts; Neural Crest; Nuclear; Organ; Process; Protein Biosynthesis; Proteoglycan; Regulation; Regulator Genes; Regulatory Element; Reporter Genes; Role; Sclerotome; Signal Pathway; Signal Transduction; Signal Transduction Pathway; Signaling Molecule; Site-Directed Mutagenesis; Skeletal Muscle; Somites; Staging; Stem cells; Sulfatases; Surface Ectoderm; Tertiary Protein Structure; Testing; Tissues; Transcriptional Activation; Transfection; Transgenic Organisms; Trauma; base; embryo culture; gene function; genetic analysis; genetic regulatory protein; human tissue; keratan sulfate proteoglycan; myogenesis; new technology; notochord; novel; progenitor; relating to nervous system; repaired; research study; skeletal; somitogenesis; stem cell division; transcription factor

Skeletal muscle provides a unique opportunity to investigate molecular genetic mechanisms that control specification of stem cell lineages within the cellular complexity of the vertebrate embryo. The proposed studies investigate developmental mechanisms that regulate the myogenic regulatory genes, MyfS and MyoD, which control the specification of skeletal muscle lineages from somite progenitors. Experiments focus specifically on the molecular mechanisms by which Sonic hedgehog (Shh) and Wnt signal molecules, produced by surrounding tissues, induce the transcriptional activation MyfS and MyoD in somitic progenitor cells, and thus initiate the process of myogenic cell specification. Complementary approaches have been developed to investigate these mechanisms in mouse and avian embryos. First, MyoD and MyfS transcriptional enhancers will be characterized using transgenic and transfection reporter gene assays, in combination with site-directed mutagenesis and nuclear factor footprinting, to map regulatory sequences and identify interacting transcription factors hypothesized to mediate Shh and Wnt induction of MyoD and MyfS.These studies undertake to distinguish whether the Gli and (3-catenin/LEFtranscription factors, which mediate Shh and Wnt signal transduction, interact directly with MyoD and MyfS enhancers to control their activation, or alternatively,whether these signals function upstream to regulate somite-specific transcription factors. Second, the developmental functions of a set of somite-activated regulatory genes, identified in differential cDNA cloning screens, will be investigated by antisense inhibition and misexpression analyses in avian embryos and by gene targeting and genetic analyses in the mouse embryo to determine their specific functions in MyoD and MyfS regulation during somite formation. These studies will focus on a family of two novel Sulfatases that were identified in our screen for somite-activated genes and are required for activation of MyoD in somites of avian embryos. These Sulfatases are hypothesized to desulfate proteoglycans in the extracellular matrix, thus controlling the localized activities of developmental signaling molecules essential for MyoD activation. Other novel somite-activated regulatory genes, identified in these screens, will be investigated to define their functions in the control of somite formation, Shh signal transduction, and MyoD and MyfS activation. The findings of these investigations are expected to lead to the discovery of novel developmental regulatory genes that control the specification of myogenic cells and other lineages in vertebrate embryos. Such knowledge will define fundamentalmechanisms that control of stem cell formation, and this information will likely lead to the development of new technologies to promote stem cell renewal in the repair of human tissues and organs damaged by disease and trauma.

骨骼肌为研究控制干细胞特化的分子遗传机制提供了独特的机会 脊椎动物胚胎细胞复杂性中的谱系。拟议的研究调查了发展机制， 调节生肌调节基因MyfS和MyoD，其控制骨骼肌谱系从体节的特化 祖先实验特别关注Sonic hedgehog（Shh）和Wnt信号分子的分子机制， 由周围组织产生，诱导体细胞祖细胞中MyfS和MyoD的转录激活，从而启动 生肌细胞特化的过程。已经开发了补充方法来研究这些机制， 小鼠和鸟类胚胎。首先，将使用转基因和转染技术表征MyoD和MyfS转录增强子。 报告基因测定，结合定点诱变和核因子足迹，以定位调控序列， 鉴定假设介导Shh和Wnt诱导MyoD和MyfS的相互作用的转录因子。 为了区分介导Shh和Wnt信号转导的Gli和β-catenin/LEF转录因子是否相互作用， 直接与MyoD和MyfS增强子结合以控制它们的激活，或者，这些信号是否在上游起作用， 调节体节特异性转录因子。第二，一组体节激活的调控基因的发育功能， 在差异cDNA克隆筛选中鉴定，将在禽类中通过反义抑制和错误表达分析进行研究 通过小鼠胚胎中的基因靶向和遗传分析，以确定它们在MyoD和MyfS中的特异性功能 在体节形成过程中的调节。这些研究将集中在一个家庭的两个新的硫酸酯酶，确定在我们的屏幕上， 体节激活基因，并且是禽类胚胎体节中MyoD激活所必需的。假设这些硫酸酯酶 在细胞外基质中的磷酸化蛋白聚糖，从而控制发育信号分子的局部活动 对MyoD激活至关重要。其他新的体节激活的调控基因，在这些筛选中确定，将进行研究， 定义了它们在控制体节形成、Shh信号转导以及MyoD和MyfS激活中的功能。的调查结果 这些研究有望发现新的发育调控基因， 脊椎动物胚胎中的肌细胞和其他谱系。这些知识将定义控制茎的基本机制 细胞形成，这一信息将可能导致新技术的发展，以促进干细胞更新， 修复因疾病和创伤而受损的人体组织和器官。