ANALYSIS OF CELL SURFACE DURING MAMMALIAN DEVELOPMENT

胚胎细胞表面的碳水化合物分子被认为是 在发育过程中，在细胞与细胞的相互作用中发挥作用。上一首 其他人对小鼠胚胎的研究表明，细胞分化是 与细胞表面显示的碳水化合物的变化有关。 其中包括重大重组，如核心部门的变化所反映的那样 合成和分子量分布，以及微妙的修饰 碳水化合物链的末端残基。建议进行的实验 这里将使用针对F9产生的单抗(抗IIC3) 胚胎癌细胞，它检测细胞表面的碳水化合物 小鼠胚胎上的IIC3抗原。免疫荧光定位 实验表明，IIC3的表达仅限于 胚胎细胞参与着床和胎盘形成。使用这个 单抗我们将继续分析IIC3抗原作为 结果如下：(1)IIC3抗原将被免疫沉淀，其分子 结构将通过柱层析、十二烷基硫酸钠-聚丙烯酰亚胺凝胶进行分析 电泳法和糖苷酶消化法；(2)免疫沉淀 来自F9细胞的材料将与免疫沉淀的抗原进行比较 从胚胎来源，分子上的不同或相似之处 结构；(3)IIC3发育性表达的继续分析 利用免疫荧光和免疫细胞化学，体内和体外 系统；(4)使用粘附性分析分析其功能作用；以及 (5)IIC3基因表达的激素调控分析 发育及其作为激素受体的潜在作用。这些 实验将提供一种新的碳水化合物抗原的详细信息 与老鼠发育有关。这一信息将帮助我们 理解细胞表面碳水化合物作为 细胞分化的调控机制。

The carbohydrate molecules of the embryonic cell surface are thought to play a role in the cell to cell interactions during development. Previous work, by others, on mouse embryos suggests that cell differentiation is associated with changes in the carbohydrate displays on the cell surface. These include major reorganizations, as reflected by changes in core synthesis and molecular weight profiles, as well as subtle modifications of terminal residues of the carbohydrate chains. The experiments proposed here will employ a monoclonal antibody (anti-IIC3), produced against F9 embryonal carcinoma cells, which detects a cell surface carbohydrate antigen (IIC3) on mouse embryos. Immunofluorescent localization experiments have indicated that the expression of IIC3 is restricted to the cells of the embryo involved in implantation and placentation. Using this monoclonal antibody we will continue to analyze the IIC3 antigen as follows: (1) The IIC3 antigen will be immunoprecipitated and its molecular structure will be analyzed by column chromatography, SDS-polyacrylimide gel electrophoresis, and glycosidase digestion; (2) the immunoprecipitable material from F9 cells will be compared to the antigens immunoprecipitated from embryonic sources, for differences or similarities in molecular structure; (3) a continued analysis of the developmental expression of IIC3 using immunofluorescence and immunocytochemistry, on in vivo and in vitro systems; (4) an analysis of its functional role using adhesion assays; and (5) an analysis of the hormonal control of IIC3 expression during development and its potential role as a hormone receptor. These experiments will provide detailed information on a new carbohydrate antigen associated with mouse development. This information will help us understand the putative role of cell surface carbohydrates as part of the controlling mechanism of cellular differentiation.