藤黄菌素体外对重组人蛋白激酶CK2全酶的抑制作用  

Inhibitory effect of luteolin on recom- binant human protein kinase CK2 holoenzyme in vitro

作　　者：林小聪[1] 刘新光[1] 陈小文[2] 陈伟珠[1] 梁念慈[1] 

机构地区：[1]广东医学院生物化学与分子生物学研究所,广东湛江524023 [2]深圳市儿童医院儿科研究所,广东深圳518026

出　　处：《第四军医大学学报》2006年第7期593-595,共3页Journal of the Fourth Military Medical University

基　　金：教育部科学技术研究重点项目(03096);广东省科技计划项目(2002C30109);湛江市科技局科技攻关计划项目(020101)

摘　　要：目的:观察体外藤黄菌素对重组人蛋白激酶CK2的抑制效果及进行酶动力学分析以确定其抑制作用类型.方法:利用基因工程技术进行克隆、表达和纯化,获得重组人CK2的α′及β亚基,并在体外等摩尔混合构成CK2全酶.通过测定药物作用后转移到CK2底物上的[γ32P]ATP的32P的放射性活度来检测藤黄菌素对酶的抑制作用及采用LineweaverBurk作图法分析其动力学.结果:藤黄菌素能显著抑制重组人蛋白激酶CK2的活性(IC50=0.86μmol/L).酶动力学分析表明,藤黄菌素与ATP呈竞争性抑制CK2的活性(Ki=0.19μmol/L),与酪蛋白则呈混合性抑制CK2的活性(Ki=0.11μmol/L).结论:藤黄菌素是一种较强的体外蛋白激酶CK2的抑制剂.AIM： To observe the inhibitory effect of luteolin on recombinant human protein kinase CK2 holoenzyme and to confirm the inhibitory type by its enzyme kinetic analysis in vitro. METHODS： Recombinant human protein kinase CK2 α′ and βsubunits were cloned, expressed and purified. The 2 subunits were mixed at equal molar ratio to reconstitute CK2 holoenzyme. Luteolin inhibitory effect was detected by determining the radioactivity of 32^P of [γ-32^P] ATP incorporated into the CK2 substrate and CK2 kinetic analysis was carried out by using the LineweaverBurk plot. RESULTS： Luteolin was proved to inhibit strongly the holoenzyme activity of recombinant human protein kinase CK2 with IC50 of 0.86 μmol/L. Kinetic studies of luteolin on recombinant human CK2 showed that luteolin acted as an inhibitor, competitive with ATP （Ki = 0. 19 μmol/L） and cooperative with casein （ Ki = 0. 11 μmol/L）. CONCLUSION ： Luteolin is an effective inhibitor of protein kinase CK2 in vitro.

关 键 词：蛋白激酶CK2 重组蛋白 全酶 藤黄菌素 酶动 力学 

分 类 号：Q555.7[生物学—生物化学] Q784