Retention of prominin in microvilli reveals distinct cholesterol-based lipid micro-domains in the apical plasma membrane
Retention of prominin in microvilli reveals distinct cholesterol-based lipid micro-domains in the apical plasma membrane
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DOI：
10.1038/35023524
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发表时间：
2000-09-01
影响因子：
21.3
通讯作者：
Huttner, WB
中科院分区：
文献类型：
--
作者：
Röper, K;Corbeil, D;Huttner, WB
膜胆固醇-鞘磷脂‘筏’的特点是不溶于非离子洗涤剂Triton X-100，涉及某些膜蛋白的分离，如胎盘碱性磷酸酶(PLAP)，到上皮细胞的顶端质膜域。在这里，我们表明，突出蛋白，一种顶部排序的五聚体膜蛋白，在跨高尔基体网络中与脂筏结合，该脂筏可溶于Triton X-100，但不溶于另一种非离子洗涤剂Lubrol WX。在细胞表面，显著蛋白仍然不溶于Lubrol Wx，并选择性地与微绒毛结合，与含有Flat的膜亚域大部分分离。胆固醇耗尽会导致突出蛋白微绒毛特异性定位的丧失，但不会导致其与翻盖的完全混合。我们认为不同的胆固醇基脂筏在膜结构域(如顶端质膜)内共存，这是膜亚结构域产生和维持的基础。
Membrane cholesterol-sphingolipid 'rafts', which are characterized by their insolubility in the non-ionic detergent Triton X-100 in the cold, have been implicated in the sorting of certain membrane proteins, such as placental alkaline phosphatase (PLAP), to the apical plasma membrane domain of epithelial cells. Here we show that prominin, an apically sorted pentaspan membrane protein, becomes associated in the trans-Golgi network with a lipid raft that is soluble in Triton X-100 but insoluble in another non-ionic detergent, Lubrol WX. At the cell surface, prominin remains insoluble in Lubrol WX and is selectively associated with microvilli, being largely segregated from the membrane subdomains containing FLAP. Cholesterol depletion results in the loss of prominin's microvillus-specific localization but does not lead to its complete intermixing with FLAP. We propose the coexistence within a membrane domain, such as the apical plasma membrane, of different cholesterol-based lipid rafts, which underlie the generation and maintenance of membrane subdomains.