CARBOHYDRATE AND GLYCOPROTEIN INTERACTIONS WITH LECTINS

描述：糖蛋白和糖脂的寡糖链 正常细胞和转化细胞作为受体参与了多种 生物过程，包括细胞识别、黏附、 分化和致癌转化。构图和 低聚糖的结构与细胞分化和 转型。凝集素是一种碳水化合物结合蛋白 在各种各样的生物体中，包括植物和动物细胞。凝集素 与包括细胞凋亡在内的细胞识别过程有关 和转移。长期目标是深入了解 糖类-凝集素识别相互作用的结构-功能作用 正常细胞和转化细胞。 凝集素与细胞表面的结合通常会导致 糖共轭受体，包括糖蛋白和糖脂，它们在 许多病例与细胞的生物反应有关。一定的 从糖蛋白和糖脂中分离出的低聚糖是 多价，并与凝集素形成交联的络合物。这导致了一个 碳水化合物-蛋白质相互作用中特异性的重要新维度： 也就是说，形成独特的，均一的交联物 碳水化合物和凝集素，即使在 分子。交联的络合物通常是结晶的，并服从于 高分辨率x射线和中子衍射研究。具体目标 用于1)确定单个交联型凝集素的原子结构 用一系列多价碳水化合物，2)研究了 动物凝集素的活性；3)探讨凝集素的交联活性 转化细胞表面的凝集素，以及4)探索解决方案 凝集素的结合特性。结果，反过来将提供 凝集素-碳水化合物结构-功能关系的研究 正常细胞和转化细胞之间的相互作用。

DESCRIPTION: The oligosaccharide chains of glycoproteins and glycolipids of normal and transformed cells have been implicated as receptors in a variety of biological processes, including cellular recognition, adhesion, differentiation and oncogenic transformation. The composition and structures of the oligosaccharides correlate with cell differentiation and transformation. Lectins are carbohydrate binding proteins which are found in a wide variety of organisms, including plants and animal cells. Lectins have been implicated in cellular recognition processes including apoptosis and metastasis. The long term objective is to gain insight into the structure-function roles of carbohydrate-lectin recognition interactions in normal and transformed cells. Binding of lectins to cell surfaces often leads to cross-linking of glycoconjugate receptors, including glycoproteins and glycolipids, which in many cases is related to the biological responses of cells. Certain oligosaccharides isolated from the glycoproteins and glycolipids are multivalent and form cross-linked complexes with lectins. This leads to an important new dimension of specificity in carbohydrate-protein interactions: namely, the formation of unique, homogeneous cross-linked complexes between carbohydrates and lectins, even in the presence of mixtures of the molecules. The cross-linked complexes are often crystalline and amenable to high resolution x-ray and neutron diffraction studies. The specific aims are to 1) determine the atomic structures of a single lectin cross-linked with a series of multivalent carbohydrates, 2) investigate the cross-linking activities of animal lectins, 3) explore the cross-linking activities of lectins on the surface of transformed cells, and 4) probe the solution binding specificities of lectins. The results, in turn, will provide insight into structure-function relationships of lectin-carbohydrate interactions in normal and transformed cells.