储存传感器STIM1可以相互控制Orai和CaV1.2通道
Youjun Wang1, Xiaoxiang Deng, Salvatore Mancarella
1Department of Biochemistry and Cardiovascular Research Center, Temple University School of Medicine, 3400 North Broad Street, Philadelphia, PA 19140, USA.
Science (New York, N.Y.)
|October 9, 2010
概括
电流相互作用分子1 (STIM1) 相互控制通道. STIM1激活抑制电压运行的通道 (CaV1.2),同时激活存储运行的Orai通道,影响细胞信号传输.
科学领域:
- 细胞生物学 细胞生物学
- 分子生理学分子生理学
- 离子通道功能的功能
背景情况:
- 信号对细胞功能至关重要,由血膜脱极化和内部储量耗尽来调节.
- 两个主要的进入通道,电压操作的通道 (CaV1.2) 和存储操作的Orai通道,被认为是独立运作的.
研究的目的:
- 调查电压运行的通道和储存运行的通道之间的监管联系.
- 阐明STIM蛋白在调解这些通道亚型之间的相互作用中的作用.
主要方法:
- 通过存储枯竭和突变修饰研究了STIM1激活.
- 使用同局部化研究检查了STIM1与CaV1.2通道的相互作用.
- 评估了STIM1对CaV1.2和Orai1通道活动的影响.
主要成果:
- STIM1激活抑制了CaV1.2通道活动,并激活了Orai1通道活动.
- 这两项监管行动均由STIM1.1.的STIM-Orai激活区域 (SOAR) 进行调解.
- STIM1定位在含有CaV1.2和Orai1通道的ER/血结处.
结论:
- STIM1作为一个中央调节器,协调CaV1.2和Orai1通道的活动.
- 这种相互控制机制对可刺激细胞和不可刺激细胞的信号产生有重大影响.
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