Structural organization of the synaptic exocytosis core complex
Structural organization of the synaptic exocytosis core complex
复制标题
DOI：
10.1016/s0896-6273(00)80399-2
复制
发表时间：
1997-11-01
期刊：
影响因子：
16.2
通讯作者：
Scheller, RH
中科院分区：
文献类型：
--
作者：
Lin, RC;Scheller, RH
突触融合蛋白、囊泡相关膜蛋白 (VAMP) 和 25 kDa 突触体相关蛋白 (SNAP-25) 形成三元“核心复合物”，是突触囊泡对接和融合过程的核心。多条证据支持蛋白质以卷曲螺旋结构组装的假设，但该螺旋中α螺旋的排列以及螺旋的整体构象尚不清楚。我们采用荧光共振能量转移（FRET）技术来研究突触融合蛋白和 VAMP 之间的比对。当受体探针与 VAMP 卷曲螺旋结构域的氨基末端偶联时，供体探针在突触融合蛋白 H3 结构域的氨基末端比在羧基末端时荧光被更大程度地猝灭。数据表明突触蛋白和 VAMP 主要以平行排列结合，并表明卷曲螺旋结构是弯曲的而不是完全伸展的。我们提出了一种模型，其中 SNAP 受体 (SNARE) 蛋白卷曲螺旋结构域的结合有助于驱动囊泡融合。
Syntaxin, vesicle-associated membrane protein (VAMP), and synaptosome-associated protein of 25 kDa (SNAP-25) form a ternary ''core complex'' central to the process of synaptic vesicle docking and fusion. Several lines of evidence support the hypothesis that the proteins assemble in a coiled-coil structure, but the alignment of alpha helices in this coil and the overall conformation of the coil are unknown. We employ the technique of fluorescence resonance energy transfer (FRET) to investigate the alignment between syntaxin and VAMP. With the acceptor probe coupled to the aminoterminal end of the VAMP coiled-coil domain, the donor probe fluorescence is quenched to a greater extent when it is on the amino-terminal end of the syntaxin H3 domain than when it is on the carboxy-terminal end. The data indicate that syntaxin and VAMP bind primarily in a parallel arrangement and suggest a coiled-coil structure that is bent rather than fully extended. We propose a model in which binding of SNAP receptor (SNARE) protein coiled-coil domains helps drive vesicle fusion.