SNARE assembly and disassembly exhibit a pronounced hysteresis
SNARE assembly and disassembly exhibit a pronounced hysteresis
复制标题
DOI：
10.1038/nsb750
复制
发表时间：
2002-02-01
期刊：
影响因子：
--
通讯作者：
Jahn, R
中科院分区：
文献类型：
--
作者：
Fasshauer, D;Antonin, W;Jahn, R
SNARE蛋白是真核生物细胞内膜融合所必需的蛋白质。它们组装成稳定的四螺旋束桥接膜，并可能为启动膜融合提供能量。在体外，可溶性SNARE片段的组装伴随着可以描述为折叠反应的主要结构重排。然而，SNARE蛋白相互作用的途径和热力学尚不清楚。在这里，我们报告说，组装和解离两个遥远的相关陷阱复合物表现出显着的滞后。组装和拆解的天然状态被动力学屏障分开，并且不能在生物相关的时间尺度上平衡。我们认为，滞后是所有陷阱复合物的一个标志，复杂的组装和拆卸遵循不同的途径，可以独立控制。
SNARE proteins are essential for intracellular membrane fusion of eukaryotes. Their assembly into stable four-helix bundles bridges membranes and may provide the energy for initiating membrane fusion. In vitro, assembly of soluble SNARE fragments is accompanied by major structural rearrangements that can be described as a folding reaction. The pathways and the thermodynamics of SNARE protein interactions, however, are not known. Here we report that assembly and dissociation of two distantly related SNARE complexes exhibit a marked hysteresis. The assembled and disassembled native states are separated by a kinetic barrier and cannot equilibrate on biologically relevant timescales. We suggest that the hysteresis is a hallmark of all SNARE complexes and that complex assembly and disassembly follow different pathways that may be independently controlled.