Another dimension to calcium signaling: a look at extracellular calcium
Another dimension to calcium signaling: a look at extracellular calcium
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DOI：
10.1242/jcs.01705
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发表时间：
2005-03-01
影响因子：
4
通讯作者：
Hofer, AM
中科院分区：
文献类型：
--
作者：
Hofer, AM
细胞生物学家最了解钙离子是一种至关重要的细胞内第二信使，它控制着无数的细胞功能。然而，最近确定的细胞表面检测器的细胞外Ca 2+促使考虑是否Ca 2+也作为一个信号分子在细胞外环境。钙离子传感器的铸件包括良好的特征细胞外钙离子传感受体，G-蛋白偶联受体最初从甲状旁腺分离。此外，其他受体、通道和膜蛋白，如间隙连接半通道、代谢型谷氨酸受体、HERG K+通道和受体Notch，都对外部[Ca 2 +]波动敏感。最近在拟南芥中克隆的Ca 2+传感器（CAS）将这一概念扩展到植物王国。新出现的证据表明，细胞外局部微环境中的[Ca 2 +]发生了可能足以通过这些传感器蛋白发挥生物作用的变化。因此，细胞外空间可能构成比以前认识到的更动态的Ca 2+信号室。
Cell biologists know the calcium ion best as a vital intracellular second messenger that governs countless cellular functions. However, the recent identification of cell-surface detectors for extracellular Ca2+ has prompted consideration of whether Ca2+ also functions as a signaling molecule in the extracellular milieu. The cast of Ca2+ sensors includes the well-characterized extracellular-Ca2+ sensing receptor, a G-protein-coupled receptor originally isolated from the parathyroid gland. In addition, other receptors, channels and membrane proteins, such as gap junction hemichannels, metabotropic glutamate receptors, HERG K+ channels and the receptor Notch, are all sensitive to external [Ca2+] fluctuations. A recently cloned Ca2+ sensor (CAS) in Arabidopsis extends this concept to the plant kingdom. Emerging evidence indicates that [Ca2+] in the local microenvironment outside the cell undergoes alterations potentially sufficient to exert biological actions through these sensor proteins. The extracellular space might therefore constitute a much more dynamic Ca2+ signaling compartment than previously appreciated.