Putney James W
National Institute of Environmental Health Sciences - NIH, Research Triangle Park, NC 27709, USA.
Adv Biol Regul. 2018 May;68:88-96. doi: 10.1016/j.jbior.2017.11.006. Epub 2017 Nov 22.
Calcium signals arise by multiple mechanisms, including mechanisms of release of intracellular stored Ca, and the influx of Ca through channels in the plasma membrane. One mechanism that links these two sources of Ca is store-operated Ca entry, the most commonly encountered version of which involves the extensively studied calcium-release-activated Ca (CRAC) channel. The minimal and essential molecular components of the CRAC channel are the STIM proteins that function as Ca sensors in the endoplasmic reticulum, and the Orai proteins that comprise the pore forming subunits of the CRAC channel. CRAC channels are known to play significant roles in a wide variety of physiological functions. This review discusses the multiple forms of STIM and Orai proteins encountered in mammalian cells, and discusses some specific examples of how these proteins modulate or mediate important physiological processes.
钙信号通过多种机制产生，包括细胞内储存钙的释放机制以及钙通过质膜通道的内流。连接这两种钙来源的一种机制是储存-操作性钙内流，其中最常见的形式涉及广泛研究的钙释放激活钙（CRAC）通道。CRAC通道的最小和必需分子成分是在内质网中作为钙传感器发挥作用的STIM蛋白，以及构成CRAC通道孔形成亚基的Orai蛋白。已知CRAC通道在多种生理功能中发挥重要作用。本综述讨论了在哺乳动物细胞中遇到的STIM和Orai蛋白的多种形式，并讨论了这些蛋白如何调节或介导重要生理过程的一些具体例子。
