抗白血病药物三尖杉酯碱对L1210细胞着丝粒蛋白含量及CenpB基因表达的影响

以小鼠白血病细胞系L1210为对象，探讨了抗白血病药物三尖杉酯碱(Harringtonine,HT或Har)对细胞内着丝粒蛋白含量及着丝粒蛋白CenP基因表达的影响。间接免疫荧光(IIF)检测结果显示，随HT作用时间延长，L1210细胞着丝粒荧光斑点减弱；免疫印迹(Western blot)检测结果显示，所用的抗着丝粒抗血清(ACA 血清)能够识别8种不同分子量的着丝粒蛋白：140、80、70、56、37、34、32和17kD。受HT作用，细胞中这些着丝粒蛋白的含量不同程度地降低。在L1210细胞中识别17、80 and l40kD蛋白质的ACA抗体也分别与分子量相当的已知为CenpA、CenpB和CenpC的3种蛋白发生交叉反应。Northern和Dot blot显示，HT的抑制作用使细胞中CenpB mRNA表达水平较之对照细胞下降。结果表明，HT可(通过抑制基因mRNA的表达)降低细胞中某些着丝粒蛋白的含量；HT对细胞的杀伤及诱导凋亡作用可能与CenpB等着丝粒蛋白基因的表达抑制有关。

Effects of Anti-leukemia Drug Harringtonine on the Levels of Centromere Proteins and Gene Expression of CenpB in L1210 Cells

In this study,we investigated the effects of the anti leukemia drug Harringtonine (HT) on the levels of centromere proteins and gene expression of centromere protein CenpB in L1210 cells.The intensity of centromere fluorescence, shown by indirect immunofluorescence staining,decreased with HT treatment.Western blot showed that the anti centromere antibody (ACA) serum used in this study recognized 8 proteins with different molecular weights:140,80,70,56,37,34,32 and 17 kD.The amounts of some of these proteins were reduced to different extents by HT treatment.The ACA antibodies that recognized the 17,80 and 140 kD proteins in L1210 cells also cross reacted with 3 proteins with similar molecular weights which are known to be CenpA,CenpB and CenpC,respectively.Northern and Dot blot analyses revealed that the level of CenpB mRNA in HT treated cells was markedly lower than that in the untreated cells.These results suggest that HT may cause a decrease in the intracellular level of some centromere proteins,probably by inhibiting mRNA expression of corresponding genes.Moreover,it is possible that the cell killing and apoptosis inducing effects of HT may be mediated by the inhibition of the expression of CenpB and other centromere protein genes.