Dotti C G, Parton R G, Simons K
Cell Biology Programme, European Molecular Biology Laboratory, Heidelberg, Germany.
Nature. 1991 Jan 10;349(6305):158-61. doi: 10.1038/349158a0.
Our recent studies suggested that neurons and epithelial cells sort viral glycoproteins in a similar manner. The apical influenza virus haemagglutinin was preferentially delivered to the axon of hippocampal neurons in culture, whereas the basolateral vesicular stomatitis virus glycoprotein was sorted to the dendrites. To investigate whether other membrane proteins showed similar sorting in neurons and epithelial cells, we have analysed the localization of a glypiated (glycosylphosphatidylinositol anchored) protein, Thy-1, in hippocampal neurons in culture. In MDCK and other epithelial cells, endogenous glycosylphosphatidylinositol (GPI)-anchored proteins, as well as mutated exogenous proteins containing the GPI-attachment signal, undergo preferential delivery to the apical surface. This polarized sorting of GPI-anchored proteins has been proposed to occur by the same mechanisms as the sorting of glycolipids to the apical surface. We report here that the neuronal GPI-protein Thy-1 is present in hippocampal neurons in culture and is exclusively located on the axonal surface. This finding further strengthens our hypothesis that the mechanisms of sorting of surface components may be similar in neurons and epithelial cells.
我们最近的研究表明，神经元和上皮细胞以相似的方式分选病毒糖蛋白。在培养的海马神经元中，顶端流感病毒血凝素优先被转运至轴突，而基底外侧水泡性口炎病毒糖蛋白则被分选至树突。为了研究其他膜蛋白在神经元和上皮细胞中是否表现出类似的分选，我们分析了一种糖基化磷脂酰肌醇锚定蛋白（Thy-1）在培养的海马神经元中的定位。在MDCK细胞和其他上皮细胞中，内源性糖基化磷脂酰肌醇（GPI）锚定蛋白以及含有GPI附着信号的突变外源性蛋白优先被转运至顶端表面。有人提出，GPI锚定蛋白的这种极性分选与糖脂分选至顶端表面的机制相同。我们在此报告，神经元GPI蛋白Thy-1存在于培养的海马神经元中，且仅位于轴突表面。这一发现进一步强化了我们的假设，即表面成分的分选机制在神经元和上皮细胞中可能相似。
