在STIM1多元化和功能中N终端SAM区域的重要作用
Matthias Sallinger1, Christina Humer1, Hwei Ling Ong2
1Institute of Biophysics, Johannes Kepler University Linz, Linz 4040, Austria.
概括
流体相互作用分子1 (STIM1) 在内质网膜中的多元化对于通道激活至关重要. 本研究确定了STIM1中的关键结构区域.
科学领域:
- 细胞生物学 细胞生物学
- 分子生物学分子生物学
- 生物物理学的生物物理.
背景情况:
- 流体相互作用分子1 (STIM1) 通过感知ER Ca2+水平来调节 (Ca2+) 稳态.
- 在Ca2+储量耗尽时,STIM1会激活Orai1通道.
- 对于STIM1光线多元化的结构基础仍然不清楚.
研究的目的:
- 阐明了STIM1光学分/多元化背后的结构机制.
- 为了确定STIM1无菌α基因 (SAM) 域中涉及多元化的特定区域.
- 研究受损STIM1多元化对信号传递的功能后果.
主要方法:
- 分子动力学 (MD) 模拟用于预测多元化部位.
- 已识别的STIM1 SAM域区域的位点定向突变发生.
- 生物化学测定和活细胞成像评估STIM1多元化和Orai1通道活性.
- 对流量和振荡频率的分析.
主要成果:
- 在MD模拟中,在STIM1 SAM域中确定了两个关键的多元化细分 (α7和近α9).
- 这些部分的点突变破坏了STIM1的高阶多元化和点形成.
- 损坏的STIM1多元化显著降低了储存运行的入量和振荡频率.
- 功能缺陷通过将突变与功能获取突变或Orai1同表达相结合来部分挽救.
结论:
- 在STIM1 SAM域内,水性驱动的相互作用对于其在单体和多体状态之间切换至关重要.
- STIM1 SAM域相互作用对于STIM1多元化和随后的Orai1通道激活至关重要.
- 这项研究揭示了STIM1介导的信号调节的结构基础.
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