Rothberg K G, Ying Y S, Kamen B A, Anderson R G
Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas 75235.
J Cell Biol. 1990 Dec;111(6 Pt 2):2931-8. doi: 10.1083/jcb.111.6.2931.
The folate receptor is a glycosyl-phosphatidylinositol (GPI)-anchored membrane protein that mediates the delivery of 5-methyltetrahydrofolate to the cytoplasm of MA104 cells. Ordinarily the receptor is sequestered into numerous discrete clusters that are associated with an uncoated pit membrane specialization called a caveola. By using two different methodological approaches, we found that the maintenance of both receptor clusters and caveolae depends upon the presence of cholesterol in the membrane. These results suggest that cholesterol plays a critical role in maintaining the caveola membrane domain and modulates the interaction of GPI-anchored membrane proteins via their phospholipid anchors.
叶酸受体是一种糖基磷脂酰肌醇(GPI)锚定的膜蛋白,它介导5-甲基四氢叶酸向MA104细胞胞质的转运。通常情况下,该受体被隔离在众多离散的簇中,这些簇与一种称为小窝的无包被凹陷膜特化结构相关。通过使用两种不同的方法,我们发现受体簇和小窝的维持都依赖于膜中胆固醇的存在。这些结果表明,胆固醇在维持小窝膜结构域中起关键作用,并通过其磷脂锚调节GPI锚定膜蛋白的相互作用。