Forskolin Regulates L-Type Calcium Channel through Interaction between Actinin 4 and β3 Subunit in Osteoblasts.
Forskolin Regulates L-Type Calcium Channel through Interaction between Actinin 4 and β3 Subunit in Osteoblasts.
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DOI：
10.1371/journal.pone.0124274
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发表时间：
2015
期刊：
影响因子：
3.7
通讯作者：
Cai H
中科院分区：
文献类型：
--
作者：
Zhang X;Li F;Guo L;Hei H;Tian L;Peng W;Cai H
允许细胞钙内流的电压依赖性l型钙通道在钙介导的细胞信号调节中是必不可少的。尽管电压依赖性l型钙通道的调节与许多因素有关，包括camp依赖性蛋白激酶A （PKA）活性和肌动蛋白细胞骨架，但对成骨细胞中调节的详细机制知之甚少。本研究通过福斯克林对肌动蛋白重组的影响及其与肌动蛋白结合蛋白actiin4的功能相互作用来研究l型钙通道活性的调节。结果表明，通过免疫共沉淀、拉下法和免疫染色检测，forskolin对成骨细胞中形成孔隙的α1c亚基的转运及其与肌动蛋白结合蛋白actiin4的相互作用无显著影响，而对成骨细胞中β3亚基的表达及其与actiin4的相互作用有显著影响。进一步作图表明，肌动蛋白4的ABD和EF结构域为相互作用位点。这种相互作用不依赖于PKA磷酸化。肌动蛋白4的下调显著降低了l型钙通道的活性。我们的研究揭示了除PKA介导的通道亚基磷酸化外，福斯克林激活腺苷酸环化酶- cAMP级联调节成骨细胞l型钙通道的新机制。这些数据揭示了腺苷酸环化酶、cAMP、PKA、肌动蛋白骨架和通道蛋白之间的相互连接在调节成骨细胞电压依赖性l型钙通道中的重要作用。
Voltage-dependent L-type calcium channels that permit cellular calcium influx are essential in calcium-mediated modulation of cellular signaling. Although the regulation of voltage-dependent L-type calcium channels is linked to many factors including cAMP-dependent protein kinase A (PKA) activity and actin cytoskeleton, little is known about the detailed mechanisms underlying the regulation in osteoblasts. Our present study investigated the modulation of L-type calcium channel activities through the effects of forskolin on actin reorganization and on its functional interaction with actin binding protein actinin 4. The results showed that forskolin did not significantly affect the trafficking of pore forming α1c subunit and its interaction with actin binding protein actinin 4, whereas it significantly increased the expression of β3 subunit and its interaction with actinin 4 in osteoblast cells as assessed by co-immunoprecipitation, pull-down assay, and immunostaining. Further mapping showed that the ABD and EF domains of actinin 4 were interaction sites. This interaction is independent of PKA phosphorylation. Knockdown of actinin 4 significantly decreased the activities of L-type calcium channels. Our study revealed a new aspect of the mechanisms by which the forskolin activation of adenylyl cyclase - cAMP cascade regulates the L-type calcium channel in osteoblast cells, besides the PKA mediated phosphorylation of the channel subunits. These data provide insight into the important role of interconnection among adenylyl cyclase, cAMP, PKA, the actin cytoskeleton, and the channel proteins in the regulation of voltage-dependent L-type calcium channels in osteoblast cells.
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影响因子：
4.8
作者：
Gerits, Nancy;Mikalsen, Theresa;Moens, Ugo
通讯作者：
Moens, Ugo
影响因子：
4.8
作者：
Li, J;Duncan, RL;Turner, CH
通讯作者：
Turner, CH
影响因子：
4
作者：
Leach, RN;Desai, JC;Orchard, CH
通讯作者：
Orchard, CH
DOI：
10.1073/pnas.86.8.2957
发表时间：
1989-04-01
影响因子：
11.1
作者：
GUGGINO, SE;LAJEUNESSE, D;SNYDER, SH
通讯作者：
SNYDER, SH
成骨细胞中的 L 型钙通道活性由肌动蛋白细胞骨架调节，与蛋白质运输无关
影响因子：
3.3
作者：
Li, Fangping;Wang, Wenwei;Zhang, Xuemei
通讯作者：
Zhang, Xuemei