Subcortical Ca2+ waves sneaking under the plasma membrane in endothelial cells
Subcortical Ca2+ waves sneaking under the plasma membrane in endothelial cells
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DOI：
10.1161/01.res.0000138447.81133.98
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发表时间：
2004-08-06
影响因子：
20.1
通讯作者：
Fujita, T
中科院分区：
文献类型：
--
作者：
Isshiki, M;Mutoh, A;Fujita, T
亚质膜钙离子，动态平衡与细胞外钙离子，影响许多信号分子，效应器，和事件在这个有限的空间。我们证明了一种新的Ca 2+波的存在下，质膜下传播响应急性升高的细胞外[Ca 2 +]，通过靶向Ca 2+传感器，cameleon，内皮质膜。这些皮层下波，空间上不同于经典的胞质Ca 2+波，起源于本地化的区域和整个subplasmalemma传播。表达的GFP与PLC δ的PH结构域从质膜到胞质溶胶的融合易位伴随着这些皮层下波，并且U 73122不仅减弱了GFP-PH δ易位，而且还减弱了皮层下Ca 2+波的峰值振幅;这一发现表明通过PLC介导的PIP 2水解参与了这些波的启动中的局部IP 3产生。NO产生的变化以及PKC β-GFP从胞质到质膜的移位，但GFP-PLA（2）到核周内膜的移位不发生变化，这些变化与质膜下Ca 2+的变化有关。因此，细胞外Ca 2+维持质膜的基础PLC活性，参与区室化皮层下Ca 2+波的启动，并调节驻留在质膜中或易位到质膜的Ca 2+依赖性信号分子。这篇文章的全文可以在http://circres.ahajournals.org上找到。
Subplasmalemmal Ca2+, dynamically equilibrated with extracellular Ca2+, affects numerous signaling molecules, effectors, and events within this restricted space. We demonstrated the presence of a novel Ca2+ wave propagating beneath the plasma membrane in response to acute elevation of extracellular [Ca2+], by targeting a Ca2+ sensor, cameleon, to the endothelial plasmalemma. These subcortical waves, spatially distinct from classical cytosolic Ca2+ waves, originated in localized regions and propagated throughout the subplasmalemma. Translocation of an expressed GFP fused with a PH domain of PLCdelta from the plasma membrane to the cytosol accompanied these subcortical waves, and U73122 attenuated not only the GFP-PHdelta translocation, but also the peak amplitude of the subcortical Ca2+ waves; this finding suggests the involvement of local IP3 production through PLC-mediated PIP2 hydrolysis in the initiation of these waves. Changes in NO production as well as PKCbeta-GFP translocation from the cytosol to the plasma membrane, but not of GFP-PLA(2) to perinuclear endomembranes, were associated with the subplasmalemmal Ca2+ changes. Thus, extracellular Ca2+ maintains the basal PLC activity of the plasma membrane, is involved in the initiation of compartmentalized subcortical Ca2+ waves, and regulates Ca2+-dependent signaling molecules residing in or translocated to the plasma membrane. The full text of this article is available online at http://circres.ahajournals.org.