Fujisawa H, Ohta K, Kameyama T, Murakami Y
Department of Molecular Biology, School of Science, Nagoya University, Japan.
Dev Neurosci. 1997;19(1):101-5. doi: 10.1159/000111192.
Plexin is a type I membrane protein which was identified in Xenopus nervous system by hybridoma technique. Molecular cloning studies demonstrated that the extracellular segment of the plexin protein possesses three internal repeats of cysteine cluster which are homologous to the cysteine-rich domain of the c-met proto-oncogene protein product. A cell aggregation test revealed that the plexin protein mediated cell adhesion via a homophilic binding mechanism, in the presence of calcium ions. Plexin was expressed in the neuronal elements composing particular neuron circuits in Xenopus CNS and PNS. These findings indicate that plexin is a new member of the Ca(2+)-dependent cell adhesion molecules, and suggest that the molecule plays an important role in neuronal cell contact and neuron network formation.
丛状蛋白是一种I型膜蛋白，通过杂交瘤技术在非洲爪蟾神经系统中被鉴定出来。分子克隆研究表明，丛状蛋白的细胞外区段具有三个半胱氨酸簇内部重复序列，这些序列与c-met原癌基因蛋白产物的富含半胱氨酸结构域同源。细胞聚集试验显示，在钙离子存在的情况下，丛状蛋白通过同嗜性结合机制介导细胞黏附。丛状蛋白在非洲爪蟾中枢神经系统和外周神经系统中构成特定神经元回路的神经元成分中表达。这些发现表明丛状蛋白是钙离子依赖性细胞黏附分子的一个新成员，并提示该分子在神经元细胞接触和神经网络形成中起重要作用。
