Actin interaction and regulation of cyclin-dependent kinase 5/p35 complex activity.
Actin interaction and regulation of cyclin-dependent kinase 5/p35 complex activity.
复制标题
肌动蛋白相互作用和细胞周期蛋白依赖性激酶 5/p35 复合物活性的调节。
DOI：
10.1111/j.1471-4159.2010.06824.x
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发表时间：
2011
影响因子：
4.7
通讯作者：
Ikezu,Tsuneya
中科院分区：
文献类型：
--
作者：
Xu,Jiqing;Tsutsumi,Koji;Tokuraku,Kiyotaka;Estes,KatherineA;Hisanaga,Shin-ichi;Ikezu,Tsuneya
神经化学杂志。（2011）116，192- 204.摘要细胞周期蛋白依赖性激酶5（Cdk 5）在神经发育、突触可塑性和神经变性过程中起关键作用。Cdk 5活性取决于与神经元蛋白p35和p25（p35的蛋白水解产物）的结合。cdk 5调节肌动蛋白细胞骨架动力学，这对神经元迁移、神经炎生长和突触形成至关重要。然而，很少有人知道肌动蛋白和Cdk 5的相互作用及其对神经元Cdk 5活性的影响。在先前的研究中，我们观察到Cdk 5/p35活性与小鼠脑中免疫共沉淀的F-肌动蛋白（丝状肌动蛋白）量呈负相关，并表明F-肌动蛋白抑制Cdk 5/p35复合物的形成[Journal of Neuroscience（2008）vol. 28，p. 14511]。本文报道的实验旨在阐明肌动蛋白与Cdk 5/p35复合物的形成及其活性之间的关系。我们提出，F-肌动蛋白制剂中的G-肌动蛋白（球状肌动蛋白）负责抑制Cdk 5/p35和Cdk 5/p25激酶活性，而不是F-肌动蛋白介导的抑制。我们发现F‐actin与p35结合，但不与p25或Cdk 5结合。我们已经证明，G‐actin直接与Cdk 5结合，而不破坏Cdk 5/p35或Cdk 5/p25复合物的形成。当使用组蛋白H1或纯化的人tau蛋白作为底物时，G-actin有效地抑制Cdk 5/p35和Cdk 5/p25活性，表明G-actin对Cdk 5活性的底物非依赖性抑制作用。最后，G-actin抑制了从野生型和p35缺陷小鼠脑中免疫沉淀的Cdk 5的活性，表明G-actin以不依赖于p35的方式抑制内源性Cdk 5活性。总之，这些结果表明一种新的机制肌动蛋白细胞骨架调节Cdk 5/p35活性。
J. Neurochem.(2011)116, 192–204.AbstractCyclin‐dependent kinase 5 (Cdk5) plays a critical role during neurodevelopment, synaptic plasticity, and neurodegeneration. Cdk5 activity depends on association with neuronal proteins p35 and p25, a proteolytic product of p35. Cdk5 regulates the actin cytoskeletal dynamics that are essential for neuronal migration, neuritic growth, and synaptogenesis. However, little is known about the interaction of actin and Cdk5 and its effect on neuronal Cdk5 activity. In a previous study, we observed that Cdk5/p35 activity is negatively correlated with co‐immunoprecipitated F‐actin (filamentous actin) amounts in the mouse brain, and suggested that F‐actin inhibits the formation of the Cdk5/p35 complex [Journal of Neuroscience (2008) vol. 28, p. 14511]. The experiments reported here were undertaken to elucidate the relationship between actin and the formation of the Cdk5/p35 complex and its activity. Instead of an F‐actin‐mediated inhibition, we propose that G‐actin (globular actin) in the F‐actin preparations is responsible for inhibiting Cdk5/p35 and Cdk5/p25 kinase activity. We found that F‐actin binds to p35 but not p25 or Cdk5. We have shown that G‐actin binds directly to Cdk5 without disrupting the formation of the Cdk5/p35 or Cdk5/p25 complexes. G‐actin potently suppressed Cdk5/p35 and Cdk5/p25 activity when either histone H1 or purified human tau protein were used as substrates, indicating a substrate‐independent inhibitory effect of G‐actin on Cdk5 activity. Finally, G‐actin suppressed the activity of Cdk5 immunoprecipitated from wild type and p35‐deficient mouse brain, suggesting that G‐actin suppresses endogenous Cdk5 activity in a p35‐independent manner. Together, these results suggest a novel mechanism of actin cytoskeletal regulation of Cdk5/p35 activity.