Developmental analysis of the role of call adhesion molecules in animal morphogenesis

我已经从小鼠和鸡胚胎的mRNA的cDNA文库中分离出了编码E-、N-和P-钙粘蛋白的cDNA。对这些钙粘蛋白cDNA一级结构的分析表明，这三种钙粘蛋白在氨基酸序列上存在同源性，表明这些分子具有共同的抗癌基因。然后，我试图将钙粘附素cDNA导入到钙粘附素活性很低的L细胞中。转染该基因的L细胞可合成钙粘附素多肽，并获得钙依赖的聚集活性。为了检测每个钙粘附素分子的特异性，我将表达E-钙粘蛋白的L细胞和表达P-钙粘附素的细胞混合，使它们聚集。结果表明，这些细胞是独立聚集的。因此，我得出结论，每一种钙粘附素分子在细胞与细胞结合中都有其特异性。

I have isolated cDNAs encoding E-, N- and P-cadherin from cDNA libraries of mRNA derived from mouse and chick embryos. The analysis of the primary structure of these cadherin cDNAs showed that there are homologies in amino acid sequences among the three cadherins, suggesting that these molecules have a common ancester. I then attempted to introduce the cadherin cDNAs into L cells which have little cadherin activity. L cells transfected with the cDNAs synthesized cadherin polypeptides and acquired the Ca^<2+>-dependent aggregating activity. These cells were morphologically transformed from the fibroblast type to the epithelial type.In order to examine the specificity of each cadherin molecule, I mixed L cells expressing E-cadherin with those expressing P-cadherin and allowed them to aggregate. The results showed that these cells aggregate independentely. Therefore, I concluded that each cadherin molecule has a specificity in cell-cell binding.