Mechanisms regulating glycan expression and function

调节聚糖表达和功能的机制

• 批准号: 7468449
• 负责人: MICHAEL TIEMEYER
• 金额: $ 27.22万
• 依托单位: UNIVERSITY OF GEORGIA
• 依托单位国家: 美国
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-07-01 至 2010-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7468449
• 关键词: Affect; Antibodies; Behavior; Cactaceae; Candidate Disease Gene; Cell Communication; Cell surface; Cells; Chemicals; Collection; Complement; Complex; Connective Tissue; Coupled; Development; Dominant-Negative Mutation; Dorsal; Drosophila genus; Ectoderm Cell; Embryo; Environment; Epitopes; Eukaryotic Cell; Family; Gene Components; Generations; Genes; Genetic Epistasis; Glycoconjugates; Grant; Heterogeneity; Horseradish Peroxidase; Human Pathology; IRAK1 gene; Immune System Diseases; Inflammatory; Life; Ligands; Link; Lipids; Liquid Chromatography; Location; Mediating; Mental Retardation; Molecular; Molecular Genetics; Muscular Dystrophies; Mutagenesis; Mutation; Neoplasm Metastasis; Neurons; Normal tissue morphology; Oligosaccharides; Pathway interactions; Placement; Polysaccharides; Proteins; Range; Receptor Signaling; Reporter; Signal Pathway; Signal Transduction; Site; Skeletal system; Specificity; Staging; Structure; Surface; Techniques; Testing; Therapeutic Intervention; Tissues; Toll-Like Receptor Pathway; Toll-like receptors; Tube; Vertebral column; base; central nervous system injury; glycosylation; glycosyltransferase; interest; member; mutant; neoplastic cell; novel; relating to nervous system

DESCRIPTION (provided by applicant): The surfaces of all eukaryotic cells are richly endowed with complex glycoconjugates. Cell surface glycans, together with the protein and lipid backbones to which they are linked, form the interfaces at which cell-cell interactions occur. Consistent with their subcellular location and immense structural diversity, specific glycans function as cell surface tags that allow cells to appropriately interact with each other and with their local environment. Therefore, mechanisms that control glycan expression also control developmental, immunological, and pathological cellular behaviors. Using genetic and molecular techniques, we discovered that a Drosophila Toll-like receptor (TLR), called Tollo/Toll-8, is a key component of a mechanism that leads to tissue-specific glycan expression. Tollo activity induces the neural-specific expression of a set of N-linked oligosaccharides known as the HRP-epitope. Tollo is not expressed on neurons but is found on ectodermal cells that contact differentiating neurons. This new function for a TLR provides the means to understand how cell-cell interactions influence tissue-specific glycosylation. The molecular pathway through which the Tollo signal is propagated will be identified and characterized by generating new mutations that affect expression of the HRP-epitope. In addition to our mutagenesis screen, we will determine whether previously identified genes, that are components of TLR signaling pathways in other contexts, are also active in regulating glycan expression. To place new genes in context and to determine the cellular mechanism of Tollo function, the ability of altered forms of Tollo to induce neural-specific glycosylation will be investigated. Finally, the specificity of Tollo induced glycan expression will be assessed by determining the diversity of HRP-epitopes in the embryo and by characterizing the full extent of glycan changes caused by loss of Tollo function. The importance of specific glycosylation for normal tissue function indicates that mechanisms controlling glycan expression should ultimately provide new targets for therapeutic intervention in a broad range of human pathologies, including CNS injury, inflammatory/immune disorders, and tumor cell metastasis.

描述（由申请人提供）：所有真核细胞的表面都富含复杂的糖缀合物。细胞表面聚糖与它们所连接的蛋白质和脂质骨架一起形成细胞-细胞相互作用发生的界面。与它们的亚细胞位置和巨大的结构多样性相一致，特异性聚糖作为细胞表面标签发挥作用，使细胞能够适当地相互作用并与其局部环境相互作用。因此，控制聚糖表达的机制也控制发育、免疫和病理细胞行为。利用遗传和分子技术，我们发现果蝇Toll样受体（TLR），称为托洛/Toll-8，是导致组织特异性聚糖表达的机制的关键组成部分。托洛活性诱导一组称为HRP-表位的N-连接寡糖的神经特异性表达。托洛不在神经元上表达，但在与分化中的神经元接触的外胚层细胞上发现。TLR的这种新功能提供了了解细胞-细胞相互作用如何影响组织特异性糖基化的方法。将通过产生影响HRP表位表达的新突变来鉴定和表征传播托洛信号的分子途径。除了我们的诱变筛选，我们将确定是否以前确定的基因，在其他情况下的TLR信号通路的组件，也积极调节聚糖的表达。为了将新基因置于背景中并确定托洛功能的细胞机制，将研究改变形式的托洛诱导神经特异性糖基化的能力。最后，通过测定胚胎中HRP表位的多样性和表征托洛功能丧失引起的聚糖变化的全部程度，评估托洛诱导聚糖表达的特异性。特异性糖基化对正常组织功能的重要性表明，控制聚糖表达的机制最终应该为广泛的人类病理学（包括CNS损伤、炎症/免疫疾病和肿瘤细胞转移）中的治疗干预提供新靶点。

项目成果

The N's and O's of Drosophila glycoprotein glycobiology.

• DOI: 10.1007/s10719-012-9442-x
• 发表时间: 2013-01
• 期刊: GLYCOCONJUGATE JOURNAL
• 影响因子: 3
• 作者: Katoh, Toshihiko;Tiemeyer, Michael
• 通讯作者: Tiemeyer, Michael

Neural-specific α3-fucosylation of N-linked glycans in the Drosophila embryo requires fucosyltransferase A and influences developmental signaling associated with O-glycosylation.

果蝇胚胎中 N 连接聚糖的神经特异性 α3-岩藻糖基化需要岩藻糖基转移酶 A 并影响与 O-糖基化相关的发育信号。

• DOI: 10.1093/glycob/cwq119
• 发表时间: 2010
• 期刊: Glycobiology
• 影响因子: 4.3
• 作者: Rendić,Dubravko;Sharrow,Mary;Katoh,Toshihiko;Overcarsh,Bryan;Nguyen,Khoi;Kapurch,Joseph;Aoki,Kazuhiro;Wilson,IainBH;Tiemeyer,Michael
• 通讯作者: Tiemeyer,Michael