山奈酚抑制蛋白激酶CK2活性  

Inhibitory Effect of Kaempferol on Protein Kinase CK2 in vitro and in HL-60 Cells

作　　者：林小聪[1] 刘新光[1] 陈小文[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

出　　处：《中国生物化学与分子生物学报》2006年第11期894-901,共8页Chinese Journal of Biochemistry and Molecular Biology

基　　金：教育部科学技术研究重点项目(No.03096);广东省自然科学基金(No.05011579);广东省科技计划项目(No.2002C30109)资助~~

摘　　要：研究体外以及HL-60细胞内山奈酚对蛋白激酶CK2的抑制作用及机制.通过测定药物作用后转移到CK2底物上的[γ-32P]ATP的32P的放射性活度,探讨山奈酚对重组人CK2全酶以及细胞内CK2活性的影响;采用多重RT-PCR检测CK2α、α′和β亚基的mRNA表达水平;通过Lineweaver-Burk作图法,分析CK2的酶动力学机制.山奈酚能显著抑制重组人CK2活性(IC50=1.88μmol/L)和HL-60细胞内的CK2活性,对细胞内CK2的作用效果强于阳性对照四溴-2-氮杂苯并咪唑(TBB).山奈酚作用2h,对CK2各亚基的mRNA表达水平均没有影响.山奈酚对重组人CK2的酶动力学分析表明,山奈酚与ATP(Ki=1.14μmol/L)及酪蛋白(Ki=1.03μmol/L)均呈非竞争性抑制作用.结果提示,山奈酚是一种有效的蛋白激酶CK2的抑制剂,其作用机制可能与其阻碍CK2与ATP以及底物的结合有关.To investigate the inhibitory effects of kaempferol on protein kinase CK2 in vitro and in HL-60 cells, the effect of recombinant human CK2 holoenzyme activity and cellular CK2 activity by kaempferol were assayed by detecting incorporation of [γ-^32P]ATP into the substrate.The mRNA expression of CK2α, α＇ and β subunits were detected by multiplex RT-PCR. CK2 kinetic analysis was carried out by using the Lineweaver- Burk plot. Kaempferol was shown to inhibit strongly the activity of protein kinase CK2 in vitro （ IC50 = 1.88 μmol/L） and in HL-60 cells. Intracellular CK2 activity assay showed that kaempferol was more effective than the positive control 4Br-2-azabenzimidazole （TBB）. In addition, CK2α, α＇ and β mRNA level was not changed fundamentally during treatment for 2 hours with kaempferol. Kinetic studies of kaempferol on recombinant human CK2 showed that the inhibition was noncompetitive with ATP （Ki = 1.14 μmol/L） and casein （Ki = 1.03 μmol/L）. These results indicated that kaempferol was an effective inhibitor of protein kinase CK2, which is assumed to interfere the combination of CK2 and ATP or its substrates.

关 键 词：蛋白激酶CK2 山奈酚 酶动力学 

分 类 号：R284.1[医药卫生—中药学] R329.2[医药卫生—中医学]