Saint-Jeannet J P, Foulquier F, Goridis C, Duprat A M
U.A. CNRS 675, Centre de biologie du développement, Université Paul Sabatier, Toulouse, France.
Development. 1989 Aug;106(4):675-83. doi: 10.1242/dev.106.4.675.
The appearance and localization of N-CAM during neural induction were studied in Pleurodeles waltl embryos and compared with recent contradictory results reported in Xenopus laevis. A monoclonal antibody raised against mouse N-CAM was used. In the nervous system of Pleurodeles, it recognized two glycoproteins of 180 and 140x10(3) M(r) which are the Pleurodeles equivalent of N-CAM-180 and -140. Using this probe for immunohistochemistry and immunocytochemistry, we showed that N-CAM was already expressed in presumptive ectoderm at the early gastrula stage. In late gastrula embryos, a slight increase in staining was observed in the neurectoderm, whereas the labelling persisted in the noninduced ectoderm. When induced ectodermal cells were isolated at the late gastrula stage and cultured in vitro up to 14 days, a faint polarized labelling of cells was observed initially. During differentiation, the staining increased and became progressively restricted to differentiating neurons.
在有尾目动物（Pleurodeles waltl）胚胎中研究了神经细胞黏附分子（N-CAM）在神经诱导过程中的出现和定位，并与非洲爪蟾（Xenopus laevis）近期报道的相互矛盾的结果进行了比较。使用了一种针对小鼠N-CAM产生的单克隆抗体。在有尾目动物的神经系统中，它识别出两种分子量分别为180和140×10³ M(r)的糖蛋白，它们相当于有尾目动物的N-CAM-180和-140。使用该探针进行免疫组织化学和免疫细胞化学研究，我们发现N-CAM在原肠胚早期的预定外胚层中就已表达。在原肠胚晚期胚胎中，神经外胚层的染色略有增加，而标记物在未诱导的外胚层中持续存在。当在原肠胚晚期分离诱导的外胚层细胞并在体外培养长达14天时，最初观察到细胞有微弱的极化标记。在分化过程中，染色增加并逐渐局限于分化中的神经元。
