Lu Jieqiong, Sun Qing, Chen Xiaoning, Wang Hanzhou, Hu Yun, Gu Jianxin
State Key Laboratory of Genetic Engineering and Gene Research Center, Shanghai Medical College of Fudan University, Box 103, Shanghai 200032, People's Republic of China.
Biochem Biophys Res Commun. 2005 May 27;331(1):153-8. doi: 10.1016/j.bbrc.2005.03.128.
p21-Activated kinase 1 (PAK1), a member of the evolutionarily conserved PAK family of serine/threonine kinases, is essential for a variety of cellular functions. Our previous studies showed that PAK1 participated in the apoptotic pathway mediated by p110C. To further investigate its functions, we used the yeast two-hybrid system to screen a human fetal brain cDNA library and identified dynein light chain 2 (DLC2)/myosin light chain (MLC) as an interacting partner of PAK1. The association of PAK1 with DLC2 was further confirmed by in vitro binding assay. With the stimulation of EGF, PAK1 interacted with HA-DLC2 in vivo and relocalized in cytoplasm near the perinuclear location in confocal microscope analysis. The deletion analysis showed that the interaction of DLC2 with PAK1 occurred within the residues 210-332 of PAK1. For that studies showed that DLC2 was a subunit of myosin complex, so it is possible that PAK1 binds to DLC2 and transports by myosin complex.
p21激活激酶1（PAK1）是丝氨酸/苏氨酸激酶中进化保守的PAK家族成员，对多种细胞功能至关重要。我们之前的研究表明，PAK1参与了由p110C介导的凋亡途径。为进一步研究其功能，我们利用酵母双杂交系统筛选人胎脑cDNA文库，并鉴定动力蛋白轻链2（DLC2）/肌球蛋白轻链（MLC）为PAK1的相互作用蛋白。体外结合试验进一步证实了PAK1与DLC2的结合。在表皮生长因子（EGF）刺激下，共聚焦显微镜分析显示PAK1在体内与HA-DLC2相互作用，并重新定位到核周附近的细胞质中。缺失分析表明，DLC2与PAK1的相互作用发生在PAK1的210-332位氨基酸残基内。鉴于研究表明DLC2是肌球蛋白复合体的一个亚基，因此PAK1有可能与DLC2结合并通过肌球蛋白复合体进行转运。
