Cholesterol is required for surface transport of influenza virus hemagglutinin.
Cholesterol is required for surface transport of influenza virus hemagglutinin.
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DOI：
10.1083/jcb.140.6.1357
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发表时间：
1998-03-23
期刊：
影响因子：
--
通讯作者：
Simons K
中科院分区：
文献类型：
--
作者：
Keller P;Simons K
从TGN到基底侧表面的转运涉及兔/ n -乙基马来酰亚胺敏感融合蛋白(NSF)/可溶性NSF附着蛋白(SNAP)/SNAP受体（SNARE）机制。相反，认为顶端运输是由洗涤剂不溶性鞘脂-胆固醇筏介导的。通过使用洛伐他汀和甲基β-环糊精降低活细胞的胆固醇水平60-70%，我们发现顶端标记蛋白流感病毒血凝素的tgn到表面的运输被减缓，而基底外侧标记蛋白水泡性口炎病毒糖蛋白的运输以及er到高尔基体的两种膜蛋白的运输不受影响。血凝素运输的减少伴随着在洗涤剂Triton X-100中的溶解度增加以及血凝素在基底侧膜上的明显错分类。此外，洛伐他汀和甲基β-环糊精对细胞胆固醇的消耗导致了根尖分泌糖蛋白gp-80的错误分选，这表明gp-80在根尖分选中使用了一种依赖于木条的机制。我们的数据首次为胆固醇在根尖膜蛋白和根尖分泌糖蛋白分选中的功能意义提供了直接证据。
Transport from the TGN to the basolateral surface involves a rab/N-ethylmaleimide–sensitive fusion protein (NSF)/soluble NSF attachment protein (SNAP)/SNAP receptor (SNARE) mechanism. Apical transport instead is thought to be mediated by detergent-insoluble sphingolipid–cholesterol rafts. By reducing the cholesterol level of living cells by 60–70% with lovastatin and methyl-β-cyclodextrin, we show that the TGN-to-surface transport of the apical marker protein influenza virus hemagglutinin was slowed down, whereas the transport of the basolateral marker vesicular stomatitis virus glycoprotein as well as the ER-to-Golgi transport of both membrane proteins was not affected. Reduction of transport of hemagglutinin was accompanied by increased solubility in the detergent Triton X-100 and by significant missorting of hemagglutinin to the basolateral membrane. In addition, depletion of cellular cholesterol by lovastatin and methyl-β-cyclodextrin led to missorting of the apical secretory glycoprotein gp-80, suggesting that gp-80 uses a raft-dependent mechanism for apical sorting. Our data provide for the first time direct evidence for the functional significance of cholesterol in the sorting of apical membrane proteins as well as of apically secreted glycoproteins.