STIM1是一个Ca2+传感器,激活CRAC通道并从Ca2+储存中迁移到血膜
Shenyuan L Zhang1, Ying Yu, Jack Roos
1Department of Physiology and Biophysics and Center for Immunology, University of California, Irvine, California 92697, USA.
Nature
|October 7, 2005
概括
储存运行的 (SOC) 流入对于细胞信号传递至关重要. STIM1充当传感器,移动到血膜,在储量耗尽时激活释放激活通道 (CRAC).
科学领域:
- 细胞生物学 细胞生物学
- 免疫学 免疫学 免疫学
- 分子生物学分子生物学
背景情况:
- 储存运行的 (SOC) 流入是不可激发细胞中关键的Ca2+进入途径.
- 在T淋巴细胞中的释激活 (CRAC) 通道对于免疫反应,基因表达和增殖至关重要.
- SOC和CRAC通道的分子身份和封闭机制在很大程度上是未知的.
研究的目的:
- 阐明SOC和CRAC通道的分子身份和封闭机制.
- 研究STIM1在CRAC通道激活中的作用.
- 为了确定Ca2+储量耗尽和SOC流入之间的缺失链接.
主要方法:
- 对Stim或STIM1.1的EF手突变体的表达.
- 免疫光显微镜.免疫光显微镜.
- 电子显微镜 (EM) 的定位.
- 表面生物化试验.表面生物化试验.
主要成果:
- 在不改变Ca2+储存量的情况下,表达Stim或STIM1构成性激活CRAC通道的EF手突变.
- 在Ca2+储量耗尽后,STIM1从类似内细胞网膜的部位转移到血膜.
- STIM1作为一个Ca2+传感器,将Ca2+储量耗尽与SOC流入联系起来.
结论:
- STIM1是CRAC通道激活的关键组成部分,作为Ca2+传感器.
- 在Ca2+储存量耗尽时,STIM1的转移到等离子体膜对于SOC流入至关重要.
- 这项研究确定STIM1是存储运行的流入途径中缺失的环节.
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