人类嗅觉CNG通道的组装,封闭和calmodulin调制的结构机制
Jing Xue1,2, Ninghai Gan3,4, Weizhong Zeng3,4
1Howard Hughes Medical Institute and Department of Physiology, University of Texas Southwestern Medical Center, Dallas, TX, USA. jxue@shsmu.edu.cn.
Nature communications
|October 23, 2025
概括
研究人员可视化了人类的嗅觉循环核酸门 (CNG) 通道,揭示了卡尔莫杜林 (CaM) 结合如何调节其在气味检测和适应中的功能.
科学领域:
- 结构生物学是结构生物学.
- 神经科学是一个神经科学.
- 分子生理学分子生理学
背景情况:
- 循环核酸入 (CNG) 通道对于哺乳动物的感官信号转导至关重要.
- 嗅觉CNG通道,一种异质四酶 (CNGA2 / A4 / B1b),由Calmodulin (CaM) 调节,以快速适应气味.
- 了解结构和CaM相互作用是嗅觉信号机制的关键.
研究的目的:
- 为了确定人体嗅觉CNG通道的冷电子显微镜 (cryo-EM) 结构.
- 阐明子单元组合的分子基础,静电测量和通道门.
- 定义卡尔莫杜林 (CaM) 结合位点,并了解Ca2+/CaM介导的抑制.
主要方法:
- 低温电子显微镜 (cryo-EM) 用于对人类原生嗅觉CNG通道的结构性确定.
- 功能分析以评估通道活动和调制.
- 与结构和功能数据集成的AlphaFold预测.
主要成果:
- 呈现了人体嗅觉CNG通道的封闭 (CaM-bound) 和开放 (cAMP-bound) 状态的冷EM结构.
- 在cAMP激活时阐明了2:1:1分单元固体测量和不对称的门机制.
- 在CNGB1b子单元上确定了两个不同的Calmodulin (CaM) 结合位点 (CaM1和CaM2).
结论:
- 这项研究为人类嗅觉CNG通道的结构和功能提供了原子层面的见解.
- 揭示了道组装,关和卡尔摩杜林 (CaM) 调节背后的分子机制.
- 提供了解嗅觉信号转导和快速适应的基础.
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