Superdiffusive motion of membrane-targeting C2 domains.
Superdiffusive motion of membrane-targeting C2 domains.
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DOI：
10.1038/srep17721
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发表时间：
2015-12-07
影响因子：
4.6
通讯作者：
Krapf D
中科院分区：
文献类型：
--
作者：
Campagnola G;Nepal K;Schroder BW;Peersen OB;Krapf D
膜靶向结构域在信号分子向质膜的募集过程中发挥着至关重要的作用。对于大多数外周蛋白来说，蛋白质与膜的相互作用是短暂的。蛋白质从膜上解离后，观察到它们在本体溶液中短暂移动后会重新结合。这种膜啤酒花对膜上反应的效率具有广泛的影响。我们使用支持的脂质双层中的单分子追踪研究膜靶向 C2 结构域的扩散。系综平均均方位移 (MSD) 表现出超扩散行为。然而，传统的单个轨迹的时间平均 MSD 分析仍然是线性的，并且没有揭示超扩散。我们的观察结果是用批量偏移来解释的，批量偏移引入了重尾分布的跳跃。这些跳跃事件使蛋白质能够在短时间内探索大面积的区域。实验结果与体介导扩散的分析模型和数值模拟一致。
Membrane-targeting domains play crucial roles in the recruitment of signalling molecules to the plasma membrane. For most peripheral proteins, the protein-to-membrane interaction is transient. After proteins dissociate from the membrane they have been observed to rebind following brief excursions in the bulk solution. Such membrane hops can have broad implications for the efficiency of reactions on membranes. We study the diffusion of membrane-targeting C2 domains using single-molecule tracking in supported lipid bilayers. The ensemble-averaged mean square displacement (MSD) exhibits superdiffusive behaviour. However, traditional time-averaged MSD analysis of individual trajectories remains linear and does not reveal superdiffusion. Our observations are explained in terms of bulk excursions that introduce jumps with a heavy-tail distribution. These hopping events allow proteins to explore large areas in a short time. The experimental results are shown to be consistent with analytical models of bulk-mediated diffusion and numerical simulations.