O-glycosylation as a sorting determinant for cell surface delivery in yeast
O-glycosylation as a sorting determinant for cell surface delivery in yeast
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DOI：
10.1091/mbc.e03-07-0511
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发表时间：
2004-04-01
影响因子：
3.3
通讯作者：
Bagnat, M
中科院分区：
文献类型：
--
作者：
Proszynski, TJ;Simons, K;Bagnat, M
关于酿酒酵母中蛋白质定位于质膜的机制知之甚少。跨膜结构域的长度以及蛋白质与脂筏的关联已被认为在细胞表面的分选中发挥作用。在这里，我们报道 Fus1p 是一种参与酵母交配过程中细胞融合的 O-糖基化整合膜蛋白，需要 O-糖基化才能进行细胞表面递送。在缺乏 PMT4（编码参与 O-糖基化初始步骤的甘露糖基转移酶）的细胞中，Fus1p 不会被糖基化并在晚期高尔基体结构中积累。缺乏O-糖基化基序的嵌合蛋白被错配至液泡并在野生型细胞的高尔基体晚期积累。通过添加 Fus1p 的 O-糖基化序列的 33 个氨基酸部分，可以恢复该蛋白质的胞吐作用。我们的数据表明，O-糖基化作为 Fus1p 细胞表面递送的分选决定因素。
Little is known about the mechanisms that determine localization of proteins to the plasma membrane in Saccharomyces cerevisiae. The length of the transmembrane domains and association of proteins with lipid rafts have been proposed to play a role in sorting to the cell surface. Here, we report that Fus1p, an O-glycosylated integral membrane protein involved in cell fusion during yeast mating, requires O-glycosylation for cell surface delivery. In cells lacking PMT4, encoding a mannosyltransferase involved in the initial step of O-glycosylation, Fus1p was not glycosylated and accumulated in late Golgi structures. A chimeric protein lacking O-glycosylation motif was missorted to the vacuole and accumulated in late Golgi in wild-type cells. Exocytosis of this protein could be restored by addition of a 33-amino acid portion of an O-glycosylated sequence from Fus1p. Our data suggest that O-glycosylation functions as a sorting determinant for cell surface delivery of Fus1p.