SNARE-mediated membrane fusion is a two-stage process driven by entropic forces.
SNARE-mediated membrane fusion is a two-stage process driven by entropic forces.
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SNARE 介导的膜融合是由熵力驱动的两阶段过程。
DOI：
10.1002/1873-3468.13277
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发表时间：
2018
期刊：
影响因子：
3.5
通讯作者：
O'Shaughnessy,Ben
中科院分区：
文献类型：
--
作者：
McDargh,ZacharyA;Polley,Anirban;O'Shaughnessy,Ben
SNARE 蛋白构成胞吐膜融合机制的核心。当囊泡相关和靶膜相关的 SNARE 拉链进入反式 SNARE 复合物（“SNAREpins”）时，就会发生融合，但所需的数量存在争议，并且协作融合的机制知之甚少。我们开发了一种高度粗粒度的分子动力学模拟来访问长聚变时间尺度，这揭示了一个两阶段过程。首先，拉链能量被消散，协同熵力将 SNAREpin 组装成一个环；其次，熵力使环膨胀，将膜压在一起并催化融合。我们预测任意数量的 SNARE 都会融合膜，但 SNARE 越多，融合速度越快。
SNARE proteins constitute the core of the exocytotic membrane fusion machinery. Fusion occurs when vesicle‐associated and target membrane‐associated SNAREs zipper into trans‐SNARE complexes (‘SNAREpins’), but the number required is controversial and the mechanism of cooperative fusion is poorly understood. We developed a highly coarse‐grained molecular dynamics simulation to access the long fusion timescales, which revealed a two‐stage process. First, zippering energy was dissipated and cooperative entropic forces assembled the SNAREpins into a ring; second, entropic forces expanded the ring, pressing membranes together and catalyzing fusion. We predict that any number of SNAREs fuses membranes, but fusion is faster with more SNAREs.