TOPOGRAPHY OF GLYCOSYLATION IN YEAST - CHARACTERIZATION OF GDPMANNOSE TRANSPORT AND LUMENAL GUANOSINE DIPHOSPHATASE ACTIVITIES IN GOLGI-LIKE VESICLES
TOPOGRAPHY OF GLYCOSYLATION IN YEAST - CHARACTERIZATION OF GDPMANNOSE TRANSPORT AND LUMENAL GUANOSINE DIPHOSPHATASE ACTIVITIES IN GOLGI-LIKE VESICLES
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DOI：
10.1073/pnas.86.18.6935
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发表时间：
1989-09-01
影响因子：
11.1
通讯作者：
HIRSCHBERG, CB
中科院分区：
文献类型：
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作者：
ABEIJON, C;ORLEAN, P;HIRSCHBERG, CB
甘露糖残基向酵母糖蛋白的“外链”添加发生在细胞的高尔基体区室中。该过程中的基本步骤被认为包括将 GDP 甘露糖从细胞质转运到高尔基体囊泡的内腔，将甘露糖转移到糖蛋白受体，将所得 GDP 水解为 GMP，以及将 GMP 和无机磷酸盐返回到细胞质。我们报告了酵母囊泡对 GDP 甘露糖转运活性和 GDP 酶的检测和表征。 GDP甘露糖以及GDP酶和另一种假定的高尔基体酶，α1，2-甘露糖基转移酶的主动转运集中在亚细胞级分中，该亚细胞级分可以通过速度蔗糖梯度离心与富含内质网标记酶的级分部分分离。
"Outer-chain" addition of mannose residues to yeast glycoproteins occurs in the Golgi compartment of the cell. Essential steps in this process are thought to include transport of GDPmannose from the cytoplasm into the lumen of Golgi vesicles, transfer of mannose to glycoprotein acceptors, hydrolysis of the resulting GDP to GMP, and return of GMP and inorganic phosphate to the cytoplasm. We report detection and characterization of a GDPmannose transport activity and a GDPase by yeast vesicles. The active transport of GDPmannose as well as the GDPase and another presumed Golgi enzyme, .alpha.1,2-mannosyltransferase, are concentrated in a subcellular fraction that can be partially separated, by velocity sucrose gradient centrifugation, from a fraction enriched in an endoplasmic reticulum marker enzyme.