Wang L J, Colella R, Yorke G, Roisen F J
Department of Anatomical Sciences and Neurobiology, University of Louisville School of Medicine, Kentucky 40292, USA.
Exp Neurol. 1996 May;139(1):1-11. doi: 10.1006/exnr.1996.0074.
The effect of ganglioside GM1 on components of the neuronal cytoskeleton was studied in Neuro-2a neuroblastoma cells using immunofluorescent, immunogold-labeled, and Western-blot analysis. Exposure of cells to GM1 for 24 h resulted in an increased microtubular network and level of tubulin, a redistribution of MAP2 immunoreactivity from perikarya to distal neuritic processes, and an increased MAP2 gold label in the subplasmalemmal cytoplasm, neuritic spines, and growth cones. A similar change in the distribution of actin-positive fluorescent immunoreactivity was observed. In contrast to the redistribution of MAP2, immunolocalization of MAP5 and tau did not change following 24 h GM1 exposure. Our results suggest that gangliosides enhance neuritogenesis by selectively altering the distribution of MAP2 from perikaryon to neuritic spines. Furthermore, the enhanced presence of MAP2 in regions known to be rich in microfilaments following GM1 treatment suggests that an interaction of MAP2 with microfilaments may be necessary for early neurite formation.
利用免疫荧光、免疫金标记和蛋白质印迹分析，在Neuro-2a神经母细胞瘤细胞中研究了神经节苷脂GM1对神经元细胞骨架成分的影响。将细胞暴露于GM1 24小时后，微管网络和微管蛋白水平增加，微管相关蛋白2（MAP2）免疫反应性从胞体重新分布到远端神经突，并且在质膜下细胞质、神经突棘和生长锥中的MAP2金标记增加。观察到肌动蛋白阳性荧光免疫反应性分布有类似变化。与MAP2的重新分布相反，暴露于GM1 24小时后，微管相关蛋白5（MAP5）和微管蛋白 tau的免疫定位没有变化。我们的结果表明，神经节苷脂通过选择性地改变MAP2从胞体到神经突棘的分布来促进神经突形成。此外，GM1处理后，已知富含微丝的区域中MAP2的存在增加，这表明MAP2与微丝的相互作用可能是早期神经突形成所必需的。
