A role for protein kinase C in the regulation of membrane fluidity and Ca2+ flux at the endoplasmic reticulum and plasma membranes of HEK293 and Jurkat cells
A role for protein kinase C in the regulation of membrane fluidity and Ca2+ flux at the endoplasmic reticulum and plasma membranes of HEK293 and Jurkat cells
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蛋白激酶 C 在 HEK293 和 Jurkat 细胞内质网和质膜膜流动性和 Ca2 通量调节中的作用
DOI：
10.1016/j.cellsig.2010.11.005
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发表时间：
2011-02-01
影响因子：
4.8
通讯作者：
Luo, Dali
中科院分区：
文献类型：
--
作者：
Chen, Lihong;Meng, Qingli;Luo, Dali
蛋白激酶C（PKC）在调节多种细胞功能（包括Ca 2+信号传导）中起着重要作用。在HEK 293和Jurkat细胞中，由几种不同激活剂刺激的Ca 2+释放和Ca 2+摄取通过用佛波醇肉豆蔻酸酯乙酸酯（PMA）或1-油酰基-2-乙酰基-sn-甘油（OAG）激活PKC而减弱，并且通过用Go 6983抑制PKC或使用shRNA敲低PKC α或PKC β而增强。免疫染色和蛋白质印迹分析表明，PKC α和PKC β II积累在质膜（PM），这些亚型，沿着PKC β I，也易位到内质网（ER）后激活PMA。膜流动性的测量结果表明，像细胞膜稳定剂牛血清白蛋白（BSA）和熊去氧胆酸盐（UDCA），PMA和OAG显着降低PM和ER膜的流动性，这些影响被阻断在PKC敲低细胞。有趣的是，BSA和UDCA都抑制了对激动剂的Ca 2+反应，其程度与PMA相同，而吐温20增加了膜流动性，提高了内部Ca 2+浓度。因此，PKC的活化诱导PKC易位到PM和ER膜和下调膜流动性，从而负调节Ca 2+通量。(C)2010年爱思唯尔公司All rights reserved.
Protein kinase C (PKC) plays a prominent role in the regulation of a variety of cellular functions, including Ca2+ signalling. In HEK293 and Jurkat cells, the Ca2+ release and Ca2+ uptake stimulated by several different activators were attenuated by activation of PKC with phorbol myristate acetate (PMA) or 1-oleoyl-2-acetyl-sn-glycerol (OAG) and potentiated by PKC inhibition with Go6983 or knockdown of PKC alpha or PKC beta using shRNA. Immunostaining and Western blotting analyses revealed that PKC alpha and PKC beta II accumulated at the plasma membrane (PM) and that these isoforms, along with PKC beta I, also translocated to the endoplasmic reticulum (ER) upon activation with PMA. Measurements of membrane fluidity showed that, like the cell membrane stabilizers bovine serum albumin (BSA) and ursodeoxycholate (UDCA), PMA and OAG significantly reduced the fluidity of both the PM and ER membranes; these effects were blocked in PKC-knockdown cells. Interestingly, both BSA and UDCA inhibited the Ca2+ responses to agonists to the same extent as PMA, whereas Tween 20, which increases membrane fluidity, raised the internal Ca2+ concentration. Thus, activation of PKC induces both translocation of PKC to the PM and ER membranes and downregulation of membrane fluidity, thereby negatively modulating Ca2+ flux. (C) 2010 Elsevier Inc. All rights reserved.