在connexin-46/50间隙连接处的诱导的N端封闭和毛孔崩
Jonathan A Flores1,2,3, Susan E O'Neill1,2, Joshua M Jarodsky1,2
1Department of Chemical Physiology and Biochemistry, Oregon Health and Science University, Portland, OR 97239, USA.
bioRxiv : the preprint server for biology
|February 24, 2025
概括
在缺血期间,离子 (Ca2+) 解离缺口连接,以保护细胞. 新的冷EM结构揭示了Ca2+结合和N终端域重塑如何控制connexin-46/50通道门,解释了细胞通信调节.
科学领域:
- 细胞生物学 细胞生物学
- 生物物理学的生物物理.
- 结构生物学 结构生物学
背景情况:
- 间隙结介于组织功能所必不可少的电气和代谢合.
- 缺血性疾病,如心脏病发作或中风,引发细胞内 (Ca2+) 水平升高.
- 这种的增加导致间隙结的解,保护健康细胞免受损伤.
研究的目的:
- 为了阐明本地连xin-46/50 (Cx46/50) 间隙连接的 Ca2+ 诱导的封闭机制.
- 提供有关Ca2+如何调节细胞间通信的详细结构见解.
主要方法:
- 使用单粒子冷电子显微镜 (cryo-EM) 进行了研究.
- 解决了Cx46/50间隙结的高分辨率结构.
主要成果:
- 在通道孔内确定了Ca2+结合点,改变了透途径.
- 观察到N-终端域重建,导致各种封闭和封闭状态.
- 亚单元的重新排列导致孔隙崩,N终端域导致硬质封锁,支持"虹膜模型"的门.
结论:
- 该研究提供了对Ca2+信号调节间隙结解的机制性见解.
- 这些发现统一并扩展了之前的间隙结口门模型.
- 这些结果对理解细胞应激反应和组织保护机制具有更广泛的意义.
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