Broadie K, Prokop A, Bellen H J, O'Kane C J, Schulze K L, Sweeney S T
Department of Zoology, University of Cambridge, England.
Neuron. 1995 Sep;15(3):663-73. doi: 10.1016/0896-6273(95)90154-x.
In synaptic transmission, vesicles are proposed to dock at presynaptic active zones by the association of synaptobrevin (v-SNARE) with syntaxin (t-SNARE). We test this hypothesis in Drosophila strains lacking neural synaptobrevin (n-synaptobrevin) or syntaxin. We showed previously that loss of either protein completely blocks synaptic transmission. Here, we attempt to establish the level of this blockade. Ultrastructurally, vesicles are still targeted to the presynaptic membrane and dock normally at specialized release sites. These vesicles are mature and functional since spontaneous vesicle fusion persists in the absence of n-synaptobrevin and since vesicle fusion is triggered by hyperosmotic saline in the absence of syntaxin. We conclude that the SNARE hypothesis cannot fully explain the role of these proteins in synaptic transmission. Instead, both proteins play distinct roles downstream of docking.
在突触传递中，有人提出囊泡通过突触小泡蛋白（v-SNARE）与 syntaxin（t-SNARE）的结合停靠在突触前活动区。我们在缺乏神经突触小泡蛋白（n-synaptobrevin）或 syntaxin 的果蝇品系中验证这一假设。我们之前表明，这两种蛋白中的任何一种缺失都会完全阻断突触传递。在此，我们试图确定这种阻断的程度。在超微结构上，囊泡仍然靶向突触前膜并正常停靠在特化的释放位点。这些囊泡是成熟且有功能的，因为在缺乏 n-synaptobrevin 时自发囊泡融合持续存在，并且在缺乏 syntaxin 时高渗盐水能触发囊泡融合。我们得出结论，SNARE 假说不能完全解释这些蛋白在突触传递中的作用。相反，这两种蛋白在停靠下游发挥不同的作用。
