STIM1 and Orai1 mediate thrombin-induced Ca2+ influx in rat cortical astrocytes
STIM1 and Orai1 mediate thrombin-induced Ca2+ influx in rat cortical astrocytes
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DOI：
10.1016/j.ceca.2012.08.004
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发表时间：
2012-12-01
期刊：
影响因子：
4
通讯作者：
Vaca, Luis
中科院分区：
文献类型：
--
作者：
Moreno, Claudia;Sampieri, Alicia;Vaca, Luis
在星形胶质细胞中，凝血酶导致细胞质Ca 2+升高，调节各种细胞保护和细胞毒性反应。星形胶质细胞对凝血酶刺激的反应是通过ER-Ca 2+释放和钙库操纵的Ca 2+内流（SOCE）之间的相互作用产生的双相Ca 2+增加。在许多细胞类型中。STIM 1和铁路已被证明是SOCE的核心组件。STIM 1感知ER-Ca 2+耗竭并结合Orai 1以激活Ca 2+内流。在这里，我们使用免疫细胞化学，过表达和siRNA检测研究的作用，STIM 1和Orai 1凝血酶诱导的钙反应在原代培养的大鼠皮质星形胶质细胞。我们发现STIM 1和rail在皮质星形胶质细胞中内源性表达，并相应地与其他哺乳动物细胞一起分布。重要的是，天然的和过表达的STIM 1重组的斑点凝血酶刺激下，这种重组是可逆的。此外，STIM 1和Orai 1的过表达增加了两倍的凝血酶引起的Ca 2+内流，而内源性STIM 1和Orai 1的敲低显着降低了这种Ca 2+内流。这些结果表明，STIM 1和铁路的基础上的一个重要部分的Ca 2+反应，星形胶质细胞在凝血酶的存在下表现出。星形胶质细胞中的凝血酶刺激导致ER-Ca 2+释放，其引起STIM 1重组，允许Orai 1活化和随后的Ca 2+内流。(C)2012爱思唯尔有限公司保留所有权利。
In astrocytes, thrombin leads to cytoplasmic Ca2+ elevations modulating a variety of cytoprotective and cytotoxic responses. Astrocytes respond to thrombin stimulation with a biphasic Ca2+ increase generated by an interplay between ER-Ca2+ release and store-operated Ca2+ entry (SOCE). In many cell types. STIM1 and rail have been demonstrated to be central components of SOCE. STIM1 senses the ER-Ca2+ depletion and binds Orai1 to activate Ca2+ influx. Here we used immunocytochemistry, overexpression and siRNA assays to investigate the role of STIM1 and Orai1 in the thrombin-induced Ca2+ response in primary cultures of rat cortical astrocytes. We found that STIM1 and rail are endogenously expressed in cortical astrocytes and distribute accordingly with other mammalian cells. Importantly, native and overexpressed STIM1 reorganized in puncta under thrombin stimulation and this reorganization was reversible. In addition, the overexpression of STIM1 and Orai1 increased by twofold the Ca2+ influx evoked by thrombin, while knockdown of endogenous STIM1 and Orai1 significantly decreased this Ca2+ influx. These results indicate that STIM1 and rail underlie an important fraction of the Ca2+ response that astrocytes exhibit in the presence of thrombin. Thrombin stimulation in astrocytes leads to ER-Ca2+ release which causes STIM1 reorganization allowing the activation of Orai1 and the subsequent Ca2+ influx. (C) 2012 Elsevier Ltd. All rights reserved.