Lipid Regulated Intramolecular Conformational Dynamics of SNARE-Protein Ykt6.
Lipid Regulated Intramolecular Conformational Dynamics of SNARE-Protein Ykt6.
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SNARE 蛋白 Ykt6 的脂质调节分子内构象动力学
DOI：
10.1038/srep30282
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发表时间：
2016-08-05
影响因子：
4.6
通讯作者：
Tan YW
中科院分区：
文献类型：
--
作者：
Dai Y;Seeger M;Weng J;Song S;Wang W;Tan YW
细胞的信息和代谢过程是通过可溶性N-乙基马来酰亚胺敏感因子附着蛋白受体(SNARE)控制的特定膜融合来传播的。SNARE蛋白Ykt6在脑神经元中高表达，在膜转运过程中发挥重要作用。研究表明，Ykt6在其Long in结构域和SNARE核心之间的界面上经历了构象变化。在这项工作中，我们利用单分子Förster共振能量转移(SmFRET)和荧光互相关光谱(FCCS)研究了大鼠Ykt6的构象分布和动力学。我们观察到Long in结构域与SNARE核心之间的分子内构象动力学发生在时间尺度~200 μ的S，并且这种动力学可以被脂类十二烷基磷胆碱的存在所调节甚至消除。我们的分子动力学(MD)模拟表明，SNARE核心显示出灵活的结构，而Long in结构域在apo状态下保持相对稳定。结合单分子实验和理论MD模拟，我们首次提供了Ykt6的定量动力学，并从定性的角度解释了功能构象的变化。
Cellular informational and metabolic processes are propagated with specific membrane fusions governed by soluble N-ethylmaleimide sensitive factor attachment protein receptors (SNARE). SNARE protein Ykt6 is highly expressed in brain neurons and plays a critical role in the membrane-trafficking process. Studies suggested that Ykt6 undergoes a conformational change at the interface between its longin domain and the SNARE core. In this work, we study the conformational state distributions and dynamics of rat Ykt6 by means of single-molecule Förster Resonance Energy Transfer (smFRET) and Fluorescence Cross-Correlation Spectroscopy (FCCS). We observed that intramolecular conformational dynamics between longin domain and SNARE core occurred at the timescale ~200 μs. Furthermore, this dynamics can be regulated and even eliminated by the presence of lipid dodecylphoshpocholine (DPC). Our molecular dynamic (MD) simulations have shown that, the SNARE core exhibits a flexible structure while the longin domain retains relatively stable in apo state. Combining single molecule experiments and theoretical MD simulations, we are the first to provide a quantitative dynamics of Ykt6 and explain the functional conformational change from a qualitative point of view.