Barthalay Y, Hipeau-Jacquotte R, de la Escalera S, Jiménez F, Piovant M
Laboratoire de Génétique et Biologie Cellulaire, CNRS, Marseille, France.
EMBO J. 1990 Nov;9(11):3603-9. doi: 10.1002/j.1460-2075.1990.tb07571.x.
Neurotactin is a 135 kd membrane glycoprotein which consists of a core protein, with an apparent molecular weight of 120 kd, and of N-linked oligosaccharides. In vivo, the protein can be phosphorylated in presence of radioactive orthophosphate. Neurotactin expression in the larval CNS and in primary embryonic cell cultures suggests that it behaves as a contact molecule between neurons or epithelial cells. Electron microscopy studies reveal that neurotactin is uniformly expressed along the areas of contacts between cells, without, however, being restricted to a particular type of junction. It putative adhesive properties have been tested by transfecting non adhesive Drosophila S2 cells with neurotactin cDNA. Heat shocked transfected cells do not aggregate, suggesting that neurotactin does not mediate homophilic cell adhesion. However, these transfected cells bind to a subpopulation of embryonic cells which probably possess a related ligand. The location at cellular junctions between specific neurons or epithelial cells, the heterophilic binding to a putative ligand and the ability to be phosphorylated are consistent with the suggestion that neurotactin functions as an adhesion molecule.
神经趋触蛋白是一种135千道尔顿的膜糖蛋白，它由一个表观分子量为120千道尔顿的核心蛋白和N - 连接寡糖组成。在体内，该蛋白在放射性正磷酸盐存在的情况下可被磷酸化。神经趋触蛋白在幼虫中枢神经系统和原代胚胎细胞培养物中的表达表明，它作为神经元或上皮细胞之间的接触分子发挥作用。电子显微镜研究显示，神经趋触蛋白沿着细胞间接触区域均匀表达，但并不局限于特定类型的连接。通过用神经趋触蛋白cDNA转染非黏附性果蝇S2细胞，对其假定的黏附特性进行了测试。热休克转染细胞不会聚集，这表明神经趋触蛋白不介导同嗜性细胞黏附。然而，这些转染细胞会与可能拥有相关配体的胚胎细胞亚群结合。在特定神经元或上皮细胞之间的细胞连接处的定位、与假定配体的异嗜性结合以及被磷酸化的能力，都与神经趋触蛋白作为黏附分子发挥作用的观点一致。
