C类Vps蛋白复合物调节液泡SNARE配对，是囊泡对接/融合所必需的。

Class C Vps protein complex regulates vacuolar SNARE pairing and is required for vesicle docking/fusion.

作者信息

Sato T K, Rehling P, Peterson M R, Emr S D

机构信息

Division of Cellular and Molecular Medicine and Howard Hughes Medical Institute, University of California at San Diego School of Medicine, La Jolla 92093, USA.

出版信息

Mol Cell. 2000 Sep;6(3):661-71. doi: 10.1016/s1097-2765(00)00064-2.

DOI:10.1016/s1097-2765(00)00064-2

PMID:11030345

Abstract

In yeast, the Class C Vps protein complex (C-Vps complex), composed of Vps11, Vps16, Vps18, and Vps33, functions in Golgi-to-vacuole protein transport. In this study, we characterized and purified this complex and identified its interaction with the syntaxin homolog Vam3. Vam3 pairs with the SNAP-25 homolog Vam7 and VAMP homolog Vti1 to form SNARE complexes during vesicle docking/fusion with the vacuole. The C-Vps complex does not bind to Vam3-Vti1-Vam7 paired SNARE complexes but instead binds to unpaired Vam3. Antibodies to a component of this complex inhibited in vitro vacuole-to-vacuole fusion. Furthermore, temperature-conditional mutations in the Class C VPS genes destabilized Vam3-Vti1-Vam7 pairing. Therefore, we propose that the C-Vps complex associates with unpaired (activated) Vam3 to mediate the assembly of trans-SNARE complexes during both vesicle docking/fusion and vacuole-to-vacuole fusion.

摘要

在酵母中，由Vps11、Vps16、Vps18和Vps33组成的C类Vps蛋白复合物（C-Vps复合物）在高尔基体到液泡的蛋白质运输中发挥作用。在本研究中，我们对该复合物进行了表征和纯化，并确定了其与 syntaxin 同源物Vam3的相互作用。Vam3与SNAP-25同源物Vam7和VAMP同源物Vti1配对，在囊泡与液泡对接/融合过程中形成SNARE复合物。C-Vps复合物不与Vam3-Vti1-Vam7配对的SNARE复合物结合，而是与未配对的Vam3结合。针对该复合物一个组分的抗体抑制了体外液泡与液泡的融合。此外，C类VPS基因中的温度条件突变使Vam3-Vti1-Vam7配对不稳定。因此，我们提出C-Vps复合物与未配对（活化）的Vam3结合，以在囊泡对接/融合和液泡与液泡融合过程中介导反式SNARE复合物的组装。