SURFACE GLYCOCONJUGATES IN DEVELOPMENTAL CELL COHESION

我们的长期目标是了解 糖缀合物有助于细胞内识别和凝聚， 形态发生过程，使用网骨藻的变形虫的聚集 discoideum作为模型，假设特定的聚糖涉及 在这种凝聚力中是识别和对接系统的一部分。主要 目标包括： (1)聚糖和类似但无活性物质的结构分析， 以识别生物活性所需的特征。 (2)证明细胞直接粘附至糖缀合物包被的 表面。 (3)对聚糖是唯一基础的假设的检验 聚集过程中的凝聚力，通过与聚糖和类似物的扰动， 聚糖抗体和化学修饰。 (4)内聚、聚集和生化缺陷的研究 条件性糖基化突变体，以测试的假设，失败 会阻止形态发生。 (5)为了研究其他分子是否也有助于凝聚力， 多个微扰实验 (6)抗体探针在鉴定和分离糖蛋白中的应用， 携带活性聚糖，以检验它们由一种 不同糖蛋白的数量。 (7)通过配体鉴定和分离聚糖受体 结合、亲和分级和光亲和标记，以及 确定识别机制是嗜同性的还是 嗜异性的

Our long term goals are to understand mechanisms by which glycoconjugates contribute to intracellular recognition and cohesion in morphogenetic processes, using aggregation of amoebae of Dictyostelium discoideum as the model, hypothesizing that specific glycans implicated in this cohesion are part of a recognition and docking system. Major objectives include: (1) Structural analysis of the glycans and similar but inactive species, to identify features required for biological activity. (2) Demonstration of direct cell adhesion to glycoconjugate-coated surfaces. (3) Tests of the hypothesis that the glycans are the sole basis for cohesion during aggregation, by perturbation with glycans and analogs, antibodies to the glycans and chemical modifications. (4) Investigation of cohesion, aggregation and biochemical defects in conditional glycosylation mutants, to test the hypothesis that failure to generate the glycans will prevent morphogenesis. (5) To examine whether other molecules also contribute to cohesion by multiple perturbant experiments. (6) Use of antibody probes to identify and isolate glycoproteins which carry the active glycans, to test the hypothesis that they carried by a number of distinct glycoproteins. (7) Identification and isolation of receptors for the glycans, by ligand binding, affinity fractionation and photoaffinity labelling, and determination of whether the recognition mechanism is homophilic or heterophilic.