GTP结合“G”蛋白参与通过高尔基体堆叠的转运。

Involvement of GTP-binding "G" proteins in transport through the Golgi stack.

作者信息

Melançon P, Glick B S, Malhotra V, Weidman P J, Serafini T, Gleason M L, Orci L, Rothman J E

机构信息

Department of Biochemistry, Stanford University, California 94305.

出版信息

Cell. 1987 Dec 24;51(6):1053-62. doi: 10.1016/0092-8674(87)90591-5.

DOI:10.1016/0092-8674(87)90591-5

PMID:2826014

Abstract

GTP gamma S irreversibly inhibits protein transport between successive compartments of the Golgi stack in a cell-free system. Fluoride, potentiated by the addition of aluminum ion, also causes a strong inhibition. These are hallmarks of the involvement of a guanine nucleotide-binding or regulatory "G" protein. Inhibition by GTP gamma S requires a cytosolic inhibitory factor that binds to Golgi membranes during inhibition. Preincubation experiments reveal that GTP gamma S blocks the function of acceptor Golgi but not donor Golgi membranes. More specifically, a processing step in between vesicle attachment and the actual fusion event seems to be affected. Electron microscopy demonstrates a corresponding 5-fold accumulation of non-clathrin-coated buds and vesicles associated with the Golgi cisternae during inhibition by GTP gamma S.

摘要

在无细胞体系中，GTPγS不可逆地抑制高尔基体堆叠中连续间隔之间的蛋白质转运。通过添加铝离子增强的氟化物也会导致强烈抑制。这些都是鸟嘌呤核苷酸结合或调节“G”蛋白参与的标志。GTPγS的抑制作用需要一种胞质抑制因子，该因子在抑制过程中与高尔基体膜结合。预孵育实验表明，GTPγS阻断受体高尔基体的功能，但不阻断供体高尔基体膜的功能。更具体地说，囊泡附着和实际融合事件之间的一个加工步骤似乎受到影响。电子显微镜显示，在GTPγS抑制过程中，与高尔基池相关的非网格蛋白包被的芽和囊泡相应地积累了5倍。