Genetic study of heparan sulfate function in development

硫酸乙酰肝素发育功能的遗传学研究

• 批准号: 7905952
• 负责人: Hiroshi Nakato
• 金额: $ 27.33万
• 依托单位: UNIVERSITY OF MINNESOTA
• 依托单位国家: 美国
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-04-29 至 2014-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7905952
• 关键词: Anabolism; Animal Model; Biochemical; Biological; Biological Models; Biological Process; Biology; Cell Differentiation process; Cell Maintenance; Cell surface; Cells; Characteristics; Complex; Cues; Data; Development; Developmental Process; Drosophila genus; Drosophila melanogaster; Enzymes; Event; Family; Fibroblast Growth Factor; Financial compensation; Genes; Genetic; Glypican; Goals; Growth Factor; Heparan Sulfate Proteoglycan; Heparitin Sulfate; Hereditary Disease; Human Genetics; In Vitro; Inorganic Sulfates; Janus kinase; Life; Ligands; Maintenance; Malignant Neoplasms; Mediating; Modeling; Molecular; Mutation; Oogenesis; Organism; Ovary; Pathway interactions; Pattern; Phenotype; Play; Proteins; Proteoglycan; Research; Role; STAT protein; Signal Transduction; Somatic Cell; Specificity; Stem cells; Structure; System; Time; Unspecified or Sulfate Ion Sulfates; Wing; axon guidance; base; cationic antimicrobial protein CAP 37; epimerase; flexibility; in vivo; insight; member; morphogens; mutant; novel; public health relevance; research study; stem cell niche; sulfation; sulfotransferase; tool

DESCRIPTION (provided by applicant): Genetic studies have demonstrated that heparan sulfate proteoglycans (HSPGs) are essential for reception of growth factors on the cell surface, formation of morphogen gradients, and axon guidance. HSPGs function in many different biological contexts, yet very little is known about the molecular basis for their activities. We are using the genetic tools available in Drosophila to investigate several outstanding questions in proteoglycan biology, including mechanisms regulating HSPG function and new developmental roles for HSPGs. One important yet unsolved question is how the specificity of HSPG functions for different ligand proteins is generated. HS chains have markedly heterogeneous structures produced by the regulated introduction of N-, 2-O-, 6-O-, and 3-O-sulfate groups. Evidence suggests that these "fine structures" of HS control discrete signaling events at the cell surface. The molecular mechanisms for this control, however, are largely unknown. One of our goals is to understand how specific HS fine structures are generated and function in vivo during development. Another goal of our research is to identify and explore novel roles of HSPGs in development. We previously found that HSPGs regulate the gradient formation of morphogens in the developmental field. We now propose a new model that HSPGs are also involved in the formation of the stem cell niche, another developmental process where cells receive positional cues in a strictly controlled fashion. Our preliminary study strongly suggests that HSPGs are required for the establishment of the germline stem cell (GSC) niche in the developing ovary through a different mode of action from their activity in the developing wing. We propose to elucidate the molecular mechanisms by which HSPGs regulate the formation of the Drosophila GSC niche. Our study also aims to identify novel HS-dependent signaling. Our preliminary data indicate that Drosophila HSPGs participate in the Janus kinase/signal transducers and activators of transcription (JAK/STAT) pathway in the ovary. The involvement of HSPGs in this pathway has never been demonstrated in any model system to date, although Unpaired, a known ligand of the Drosophila JAK/STAT pathway, is a heparin binding protein. We will investigate the roles of HSPGs in this pathway using Drosophila oogenesis as our model. Our specific aims of the proposed research are: Aim 1. Explore the molecular functions of HS modifying enzymes in signaling during Drosophila development. Aim 2. Explore roles of HSPGs in Drosophila germline stem cell niche. Aim 3. Establish roles of HSPGs in the JAK/STAT pathway. PUBLIC HEALTH RELEVANCE: Heparan sulfate proteoglycans (HSPGs) are involved in a variety of biological processes such as growth factor signaling, morphogen gradient formation, and axon guidance. Disruption of normal HSPG biosynthesis leads to many human genetic diseases as well as cancer formation. The long term goal of this study is to understand the molecular basis for the function and biosynthesis of HSPGs during development using a genetically tractable model organism, Drosophila melanogaster.

描述（由申请人提供）：遗传学研究表明，硫酸乙酰肝素蛋白聚糖（HSPG）对于细胞表面生长因子的接收、形态发生素梯度的形成和轴突引导至关重要。 HSPG 在许多不同的生物环境中发挥作用，但对其活性的分子基础知之甚少。我们正在利用果蝇中可用的遗传工具来研究蛋白多糖生物学中的几个突出问题，包括调节 HSPG 功能的机制和 HSPG 的新发育作用。一个重要但尚未解决的问题是 HSPG 对不同配体蛋白的功能特异性是如何产生的。 HS 链具有通过调节 N-、2-O-、6-O- 和 3-O- 硫酸酯基团的引入而产生的明显异质结构。有证据表明，HS 的这些“精细结构”控制着细胞表面的离散信号传导事件。然而，这种控制的分子机制很大程度上是未知的。我们的目标之一是了解特定的 HS 精细结构是如何在发育过程中产生并在体内发挥作用的。我们研究的另一个目标是识别和探索 HSPG 在发育中的新作用。我们之前发现HSPGs调节发育领域中形态发生素的梯度形成。我们现在提出了一个新模型，即 HSPG 还参与干细胞生态位的形成，这是细胞以严格控制的方式接收位置线索的另一个发育过程。我们的初步研究强烈表明，HSPG 是在发育中的卵巢中建立生殖系干细胞 (GSC) 生态位所必需的，其作用方式与它们在发育中的翅膀中的活动不同。我们建议阐明 HSPG 调节果蝇 GSC 生态位形成的分子机制。我们的研究还旨在识别新的 HS 依赖性信号传导。我们的初步数据表明，果蝇 HSPG 参与卵巢中的 Janus 激酶/信号转导和转录激活剂 (JAK/STAT) 途径。尽管果蝇 JAK/STAT 途径的已知配体 Unpaired 是一种肝素结合蛋白，但迄今为止，尚未在任何模型系统中证实 HSPG 参与该途径。我们将使用果蝇卵子发生作为我们的模型来研究 HSPG 在此途径中的作用。我们拟议研究的具体目标是： 目标 1. 探索果蝇发育过程中 HS 修饰酶在信号传导中的分子功能。目标 2. 探索 HSPG 在果蝇生殖干细胞生态位中的作用。目标 3. 确定 HSPG 在 JAK/STAT 通路中的作用。公共健康相关性：硫酸乙酰肝素蛋白聚糖 (HSPG) 参与多种生物过程，例如生长因子信号传导、形态发生素梯度形成和轴突引导。正常 HSPG 生物合成的破坏会导致许多人类遗传疾病以及癌症的形成。本研究的长期目标是使用遗传易处理的模型生物（黑腹果蝇）了解 HSPG 在发育过程中的功能和生物合成的分子基础。