Fujimura Shoko, Mio Kazuhiro, Kuramochi Masahiro, Sekiguchi Hiroshi, Ikezaki Keigo, Mio Muneyo, Hengphasatporn Kowit, Shigeta Yasuteru, Kubo Tai, Sasaki Yuji C
AIST-UTokyo Advanced Operando-Measurement Technology Open Innovation Laboratory (OPERANDO-OIL), National Institute of Advanced Industrial Science and Technology (AIST), 6-2-3 Kashiwanoha, Chiba 277-0882, Japan.
Molecular Profiling Research Center for Drug Discovery, National Institute of Advanced Industrial Science and Technology (AIST), Chiba 277-0882, Japan.
J Phys Chem B. 2020 Dec 24;124(51):11617-11624. doi: 10.1021/acs.jpcb.0c08250. Epub 2020 Dec 9.
Transient receptor potential vanilloid type 1 (TRPV1) channels are activated by heat, vanilloids, and extracellular protons. Cryo-EM has revealed various conformations of TRPV1, and these structures suggest an intramolecular twisting motion in response to ligand binding. However, limited experimental data support this observation. Here, we analyzed the intramolecular motion of TRPV1 using diffracted X-ray tracking (DXT). DXT analyzes trajectories of Laue spots generated from attached gold nanocrystals and provides picometer spatial and microsecond time scale information about the intramolecular motion. We observed that both an agonist and a competitive antagonist evoked a rotating bias in TRPV1, though these biases were in opposing directions. Furthermore, the rotational bias generated by capsaicin was reversed between the wild-type and the capsaicin-insensitive Y511A mutant. Our findings bolster the understanding of the mechanisms used for activation and modulation of TRP channels, and this knowledge can be exploited for pharmacological usage such as inhibitor design.
瞬时受体电位香草酸亚型1（TRPV1）通道可被热、香草酸类物质和细胞外质子激活。冷冻电镜已揭示了TRPV1的多种构象，这些结构表明其存在响应配体结合的分子内扭转运动。然而，仅有有限的实验数据支持这一观察结果。在此，我们使用衍射X射线追踪（DXT）分析了TRPV1的分子内运动。DXT分析附着的金纳米晶体产生的劳厄斑点轨迹，并提供有关分子内运动的皮米级空间和微秒级时间尺度信息。我们观察到，激动剂和竞争性拮抗剂均在TRPV1中引发了旋转偏向，尽管这些偏向方向相反。此外，辣椒素产生的旋转偏向在野生型和辣椒素不敏感的Y511A突变体之间发生了逆转。我们的研究结果有助于加深对TRP通道激活和调节机制的理解，并且这一知识可用于诸如抑制剂设计等药理学应用。
