Cdk5/p35激酶与肌动蛋白细胞骨架结合关系的鉴定

Characterization of Association of Actin Cytoskeleton with Cdk5/p35 Kinase

Cdk5,一种多功能的丝氨酸/苏氨酸蛋白激酶,其活性只有通过结合其神经特异性调节亚基才能被激活。p35是Cdk5的两个主要调节亚基之一。尽管Cdk5/p35激酶可以调控神经细胞中肌动蛋白细胞骨架的动态变化,但直到目前为止Cdk5/p35激酶与肌动蛋白细胞骨架的结合关系仍不是很清楚。现利用几种不同的方法对两者的结合关系进行了初步鉴定。目前的试验结果表明在鼠脑组织中肌动蛋白细胞骨架是Cdk5/p35超大蛋白复合体的一个组分,p35可以直接结合纤维状肌动蛋白,这说明在鼠脑组织或神经细胞中Cdk5很有可能是通过p35结合到肌动蛋白细胞骨架上并进一步调控肌动蛋白细胞骨架的动态活动的。

Cdk5 is a small serine/threonine kinase and its activity requires association with its neuronal specific regulatory subunits, p35 is one of two regulatory subunits for Cdk5. Although the regulation of actin cytoskeleton is one of the most important functions of Cdk5/p35 kinase in neuronal central system, it is still unclear whether the actin cytoskeleton is associated with Cdk5/p35 kinase. In this study, the association of Cdk5/p35 kinase with actin cytoskeleton was characterized using several different methods. The present results demonstrated actin cytoskeleton was identified as one major component of Cdk5/p35 macrocomplex and p35 can directly bind to filamentous actin. Thus we deduce that Cdk5 might associate with actin cytoskeleton via its regulatory subunit p35 in brain to further regulate the actin cytoskeleton dynamics.