Hydrodynamics govern the pre-fusion docking time of synaptic vesicles.
Hydrodynamics govern the pre-fusion docking time of synaptic vesicles.
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流体动力学控制突触小泡的融合前对接时间。
DOI：
10.1098/rsif.2017.0818
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发表时间：
2018
期刊：
影响因子：
--
通讯作者：
Hui,Chung-Yuen
中科院分区：
文献类型：
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作者：
Singh,Pankaj;Hui,Chung-Yuen
突触小泡融合是神经传递过程中的关键步骤。通过带状突触处的带状结构和 SNARE 蛋白的调节，充满神经递质的囊泡预先停靠在突触处。电脉冲触发预先对接的囊泡的融合过程，导致融合孔的形成，随后导致神经递质释放到突触间隙中。在这项研究中，脂质膜的连续体模型和润滑理论被用来确定突触小泡在水动力影响下的遍历时间。我们发现，穿越时间很大程度上取决于驱动力随着囊泡和质膜之间间隙的闭合而衰减或增长的速度。如果选择正确的行为，则获得的遍历时间约为几百毫秒，并且位于实验获得的大约 250 毫秒的值内（Zenisek D、Steyer JA、Almers W. 2000Nature406, 849–854 (doi:10.1038/35022500)）。我们假设存在两种不同的力行为，这符合带状突触处突触囊泡融合前对接的实验结果。所提出的力模型的共同主题是驱动力必须随着夹紧量的变化而快速增加或减少。
Synaptic vesicle fusion is a crucial step in the neurotransmission process. Neurotransmitter-filled vesicles are pre-docked at the synapse by the mediation of ribbon structures and SNARE proteins at the ribbon synapses. An electrical impulse triggers the fusion process of pre-docked vesicles, leading to the formation of a fusion pore and subsequently resulting in the release of neurotransmitter into the synaptic cleft. In this study, a continuum model of lipid membrane along with lubrication theory is used to determine the traverse time of the synaptic vesicle under the influence of hydrodynamic forces. We find that the traverse time is strongly dependent on how fast the driving force decays or grows with closure of the gap between the vesicle and the plasma membrane. If the correct behaviour is chosen, the traverse time obtained is of the order of a few hundred milliseconds and lies within the experimentally obtained value of approximately 250 ms (Zenisek D, Steyer JA, Almers W. 2000Nature406, 849–854 (doi:10.1038/35022500)). We hypothesize that there are two different force behaviours, which complies with the experimental findings of pre-fusion docking of synaptic vesicles at the ribbon synapses. The common theme in the proposed force models is that the driving force has to very rapidly increase or decrease with the amount of clamping.