为了分析不同启动子在白血病细胞中驱动外源基因表达能力的差异, 文章选择了4种含不同启动子EF1α、PGK、Ubiquitin和CMV驱动的GFP报告基因的慢病毒载体, 用以感染4种不同的白血病细胞株——NB4、HL60、Kasumi和THP1, 利用荧光显微镜、流式细胞仪和荧光定量PCR的方法检测其GFP表达效率, 发现EF1α启动子驱动GFP表达的能力最强, CMV最弱, PGK和Ubiquitin则介于两者之间。该结果提示在白血病细胞中研究基因功能时, 应根据不同的研究需求选择最为合适的启动子。
To investigate the variance in exogenous gene expression driven by the different promoters in leukemia cells, four GFP reporter lentivirus vectors carrying different promoters, including EF1α, PGK, Ubiquitin and CMV, were selected. Leukemia cell lines NB4, THP1, HL60 and Kasumi were infected with lentivirus produced from these reporter vectors, respectively. Then, fluorescence microscope, flow cytometry and fluorescence quantitative PCR were used to detect the GFP expression strength. The results of this study clearly showed that the expression levels of the reporter genes with four different promoters were significantly different. Among them, EF1α drove the highest level of GFP expression, while CMV promoter induced the lowest level. Our results suggested that promoters should be carefully chosen in order to get the ap-propriate exogenous expression level in leukemia cells according to the study need.
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