哺乳动物内溶性TRPML1通道在纳米光盘中的结构

Qingfeng Chen1,2,3, Ji She1,2, Weizhong Zeng1,2,3

  • 1Department of Physiology, University of Texas Southwestern Medical Center, Dallas, Texas 75390-9040, USA.

Nature
|October 12, 2017
PubMed

Insights

TRPML1通道的结构揭示了酸丁氨基-3,5-双酸盐 (PtdIns(3,5) P2) 如何调节其功能,为化体储存疾病 (如粘脂症) 提供了洞察力.

科学领域:

  • 结构生物学 结构生物学
  • 分子生理学分子生理学
  • 细胞生物学 细胞生物学

背景情况:

  • 暂时受体潜在粘脂蛋白1 (TRPML1) 是溶酶体和内体膜中的关键离子通道.
  • TRPML1功能障碍会导致IV型粘脂症,这是一种严重的溶酶体储存障碍.

研究的目的:

  • 为了确定鼠标TRPML1通道的高分辨率结构.
  • 阐明TRPML1门和离子透的分子机制.

主要方法:

  • 在纳米磁盘中嵌入的TRPML1的单颗粒电子冷显微镜 (冷-EM).
  • 位点定向突变发生以探测功能机制.

主要成果:

  • 该结构揭示了PtdIns{3,5) P2与N端结合,以及一个螺旋-转-螺旋动机,可能与孔开口结合.
  • 选择性波器和光线Ca2+阻断部位解释了pH和Ca2+调节通道活性.
  • 一个发光的天花板创建一个静电陷有利于双价,和不同的S4-S5链接器形状表明一个PtdInsP2门机制.

结论:

  • TRPML1结构为了解其由PtdIns{3,5) P2调节及其在溶酶体功能中的作用提供了分子基础.
  • 这种结构性洞察对于开发TRPML1相关疾病的治疗策略至关重要.
抽象的

No abstract available in PubMed .

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