钙释放激活钙离子通道的发现及研究现状

Ca2+释放激活Ca2+(CRAC)通道是位于非兴奋性细胞质膜上的慢Ca2+通道,是非兴奋性细胞(尤其T淋巴细胞和HEK 293细胞)中胞外Ca2+进入细胞内的主要途径.Ca2+内流是T淋巴细胞激活的最重要的生理生化特征之一.Orai1蛋白单体是组成CRAC通道的亚基,4个Orai1蛋白亚基构成一个四聚体CRAC通道.内质网Ca2+浓度的降低使得STIM1发生定向运动并产生聚集,从而激活了CRAC通道.STIM1蛋白把内质网Ca2+的损耗与CRAC通道上的Ca2+内流联系起来,行使了Ca2+浓度感受器的功能.

Discovery and Recent Progress of Calcium Release Activated Calcium Channels

Calcium-release-activated calcium (CRAC) channel is a slow Ca~(2+) channel,which locates in the plasma membrane in non-excitable cells.CRAC channel is the major Ca~(2+) entry pathway in non-excitable cells,especially in T lymphocytes and HEK 293 cells.Ca~(2+) influx is one of the most important physiological-biochemical characteristics of T lymphocytes cell.Orail is the subunit of CRAC channel,and four Orail monomers constitute one tetrameric CRAC channel.STIM1 functions as the missing link between endoplasmic reticulum Ca~(2+) depletion and CRAC influx.At present,STIM1 has been widely accepted as a Ca~(2+) sensor that relays the store depletion information to plasma membrane and thus to activate CRAC channel.