Mueller Philipp, Quintana Ariel, Griesemer Desiree, Hoth Markus, Pieters Jean
Biozentrum, University of Basel, Klingelbergstrasse 70, CH 4056 Basel, Switzerland.
FEBS Lett. 2007 Jul 24;581(18):3557-62. doi: 10.1016/j.febslet.2007.06.068. Epub 2007 Jul 3.
Lymphocyte signaling and activation leads to the influx of extracellular Ca(2+) via the activation of Ca(2+) release activated Ca(2+) (CRAC) channels in the plasma membrane. Activation of CRAC channels occurs following emptying of the endoplasmic reticulum intracellular Ca(2+) stores. One model to explain the coupling of store-emptying to CRAC activation is the secretion-like conformational coupling model. This model proposes that store depletion increases junctions between the endoplasmic reticulum and the plasma membrane in a manner that could be regulated by the cortical actin cytoskeleton. Here, we show that stabilization or depolymerization of the actin cytoskeleton failed to affect CRAC activation. We therefore conclude that rearrangement of the actin cytoskeleton is dispensable for store-operated Ca(2+) entry in T-cells.
淋巴细胞信号传导与激活会通过激活质膜中的钙释放激活钙（CRAC）通道，导致细胞外Ca(2+)内流。内质网细胞内Ca(2+)储存排空后，CRAC通道会被激活。一种解释储存排空与CRAC激活偶联的模型是分泌样构象偶联模型。该模型提出，储存耗竭会以一种可能受皮质肌动蛋白细胞骨架调节的方式增加内质网与质膜之间的连接。在此，我们表明肌动蛋白细胞骨架的稳定或解聚未能影响CRAC激活。因此，我们得出结论，肌动蛋白细胞骨架的重排对于T细胞中储存操纵的Ca(2+)内流是可有可无的。
