OLIGOSACCHARIDE STRUCTURE AND FUNCTION IN RECOGNITION

低聚糖结构和功能的识别

• 批准号: 2086985
• 负责人: JACQUES U BAENZIGER
• 金额: $ 33.74万
• 依托单位: WASHINGTON UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 1977
• 资助国家: 美国
• 起止时间: 1977-08-01 至 1999-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2086985
• 关键词: RNase protection assay; SDS polyacrylamide gel electrophoresis; carbohydrate receptor; carbohydrate sequence; complementary DNA; genetic regulation; glycoproteins; hormone regulation /control mechanism; in situ hybridization; laboratory rabbit; laboratory rat; ligands; liver; membrane proteins; newborn animals; oligosaccharides; protein sequence; radioimmunoassay; receptor binding; site directed mutagenesis; western blottings

The oligosaccharides on soluble and membrane glycoproteins exhibit tremendous structural diversity, suggesting they encode highly specific information. For this to be the case there must exist: l) Unique oligosaccharide structures, 2) Highly specific glycosyltransferases, and 3) Receptors capable of recognizing these structures and utilizing their unique information. Biologic functions making use of information encoded in oligosaccharides are likely to be manifest primarily in multicellular organisms and include such phenomena as cell:cell recognition, cell:matrix recognition, and both intra- and extra-cellular trafficking of glycoproteins. The challenge has been to identify systems which utilize the structural information encoded in oligosaccharides for a biologic purpose. We have identified a major new carbohydrate-specific receptor system in liver which regulates the circulatory half life and, thereby, the biologic activity of the glycoprotein hormone lutropin and other glycoproteins bearing terminal SO4-4GalNAc-beta, 14GlcNAc-beta1, 2Man- alpha (S4GGnM) on their oligosaccharides. The synthesis of S4GGnM-terminal structures is highly regulated and they are found on only a limited number of glycoproteins. Hepatic endothelial cell express >500,000 S4GGnM-binding sites/cell at their surface. The S4OGnM-receptor has been isolated from rat liver and will be extensively characterized using approaches we have developed for other carbohydrate-specific systems. The properties of the receptor will be defined in isolated hepatic endothelial cells. The primary structure will be determined by cDNA analysis. Proteolytic fragmentation and mutagenesis will be used to define the regions involved in ligand binding and targeting. Additional potential functions will be established by using the receptor to identify other glycoproteins bearing S4GGnM-terminal structures. Cells expressing the receptor in other tissues will be identified and characterized to establish if the receptor is part of a multigene family. Immunolocalization and in situ hybridization will be used to examine the regulation of S4GGnM-receptor expression during fetal development, pregnancy, and gain of sexual maturity in newborn rats. Since many glycoproteins including membrane glycoproteins on normal and malignant cells, surface glycoproteins on viruses, growth factor precursors, coagulation factors, complement components, and hormones may interact with the receptor system it has tremendous potential relevance to both pathologic and normal states.

可溶性糖蛋白和膜糖蛋白上的寡糖表现出 巨大的结构多样性，表明它们编码高度特异性的 信息。为此，必须存在： l) 唯一 寡糖结构，2) 高度特异性的糖基转移酶，以及 3）能够识别这些结构并利用它们的受体 独特的信息。利用编码信息的生物功能 寡糖中的现象可能主要表现在多细胞中 有机体，包括细胞：细胞识别、细胞：基质等现象 识别以及细胞内和细胞外的运输 糖蛋白。面临的挑战是确定利用的系统 生物制品寡糖中编码的结构信息 目的。我们发现了一种主要的新碳水化合物特异性受体 肝脏中调节循环半衰期的系统，从而 糖蛋白激素促黄体激素和其他激素的生物活性 带有末端 SO4-4GalNAc-beta、14GlcNAc-beta1、2Man- 的糖蛋白 α (S4GGnM) 在其寡糖上。 S4GGnM-末端的合成 结构受到严格监管，且数量有限 糖蛋白。肝内皮细胞表达 >500,000 个 S4GGnM 结合 其表面的位点/细胞。 S4OGnM 受体已从 大鼠肝脏，将使用我们拥有的方法进行广泛的表征 专为其他碳水化合物特定系统而开发。的属性 受体将在分离的肝内皮细胞中定义。这 一级结构将通过cDNA分析确定。蛋白水解 将使用片段化和诱变来定义所涉及的区域 配体结合和靶向。额外的潜在功能将是 通过使用受体识别其他糖蛋白而建立 S4GGnM-末端结构。在其他组织中表达受体的细胞 将被识别和表征以确定受体是否是一部分 属于多基因家族。免疫定位和原位杂交将 用于检查 S4GGnM 受体表达的调节 新生大鼠的胎儿发育、妊娠和性成熟。 由于许多糖蛋白，包括正常和正常细胞上的膜糖蛋白 恶性细胞、病毒表面糖蛋白、生长因子 前体、凝血因子、补体成分和激素可能 与受体系统相互作用，它具有巨大的潜在相关性 病理状态和正常状态。