多个弱制动器协同作用,调节STIM1并控制存储运行的进入
bioRxiv : the preprint server for biology
|June 6, 2025
概括
流体相互作用分子1 (STIM1) 通过与Orai1通道相互作用来调节的进入. 四个弱约束保持STIM1在一个不活跃的状态,允许精确的信号.
科学领域:
- 细胞生物学 细胞生物学
- 离子通道调节的分子机制
- 信号通路是的信号通路.
背景情况:
- 流体相互作用分子1 (STIM1) 是一个内网膜 (ER) (Ca2+) 传感器,对于存储运行的进入至关重要.
- 在ER Ca2+耗尽时,STIM1会激活Orai1通道,但必须在ER Ca2+储量充满时保持不活跃,以防止细胞功能障碍.
- 了解STIM1静止状态的调节机制对于理解平稳和相关病理至关重要.
研究的目的:
- 阐明管理STIM1.1不活跃,静止状态的结构和监管机制.
- 为了确定保持STIM1在低基底活性状态的特定分子相互作用.
主要方法:
- 单分子弗斯特共振能量转移 (smFRET) 测量在脂质膜中复制的全长二维STIM1.
- 使用AlphaFold2进行计算结构建模,以分析STIM1.1的静态形态.
主要成果:
- 通过四种不同的,相对较弱的抑制抑制 (制动器) 精确控制STIM1活动.
- 与Ca2+结合的EF-SAM域起到固体制动作用,而涉及CRAC激活域 (CAD) 的CC1α1,CC3的细胞结合相互作用以及脂蛋白相互作用稳定了非活性构造.
- 在CC1α2/3领域内的额外的疏水和静电相互作用形成了第四个制动.
- 任何一个车的中断都足以激活STIM1.
结论:
- STIM1的休息状态是由四个弱抑制机制的合作网络维持的.
- 这种多车系统确保STIM1在静止细胞中保持不活跃,但在ER Ca2+耗尽时允许可逆激活.
- 这些发现为调节信号和STIM1-Orai1相互作用提供了关键的见解.
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