Orai-2 is localized on secretory granules and regulates antigen-evoked Ca2+ mobilization and exocytosis in mast cells
Orai-2 is localized on secretory granules and regulates antigen-evoked Ca2+ mobilization and exocytosis in mast cells
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DOI：
10.1016/j.bbrc.2014.07.060
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发表时间：
2014-08-15
影响因子：
3.1
通讯作者：
Hirashima, Naohide
中科院分区：
文献类型：
--
作者：
Ikeya, Miho;Yamanoue, Kiyoshi;Hirashima, Naohide
通过Ca 2+通道增加细胞内Ca 2+是肥大细胞分泌炎症介质的不可缺少的步骤。最近报道，奥赖-1负责通过耗尽储存的Ca 2+而激活的Ca 2+内流。奥赖有三种亚型：orai-1、奥赖-2和奥赖-3;然而，对orai-1以外的亚型知之甚少。我们发现奥赖-2在RBL-2 H3中表达并定位于分泌颗粒上。敲低奥赖-2可显著减弱抗原刺激诱导的细胞内Ca ~（2+）释放，而thapsigargin诱导的细胞内Ca ~（2+）释放不受影响。此外，在敲低细胞中，由抗原刺激诱导的胞吐释放被抑制。这一观察结果表明，在分泌细胞的奥赖亚型的一个新的作用。(C)2014爱思唯尔公司All rights reserved.
The increase in intracellular Ca2+ through the Ca2+ channel is an indispensable step for the secretion of inflammatory mediators by mast cells. It was recently reported that Orai-1 is responsible for the Ca2+ influx that is activated by depletion of stored Ca2+. There are three isoforms of Orai: orai-1, Orai-2, and Orai-3; however, isoforms other than orai-1 are poorly understood. We found that Orai-2 is expressed and localized on secretory granules in RBL-2H3. Ca2+ release from Ca2+ store, induced by antigen stimulation, was significantly attenuated by knockdown of Orai-2, while that induced by thapsigargin was not affected. Furthermore, exocytotic release induced by antigen stimulation was inhibited in knockdown cells. This observation suggests a new role of orai isoforms in secretory cells. (C) 2014 Elsevier Inc. All rights reserved.