慢病毒荧光素酶载体介导的miRNA靶向基因筛选系统的建立及应用

Establishment and Application of Lentivirus Luciferase Reporter-mediated miRNA Target Gene Screening System

本研究旨在建立miRNA靶基因高通量筛选系统,筛选出能调控p21NAs,以便试验验证及探索这些miRNA的生物学功能及意义。利用分子克隆技术构建并鉴定2个慢病毒表达载体-pWPXL-Luc及pWPXL-Luc-P21-3'UTR,分别与包装载体psPAX-2及PDM2G共转染HEK 293T细胞;包装病毒颗粒,感染HEK 293细胞,获得稳定单表达荧光素酶及共表达荧光素酶与P21-3'UTR的细胞株,前者在后续实验中作为对照;采用荧光素酶检测试剂检测pWPXL-Luc病毒感染后的293细胞的荧光素酶活性。结果表明:包装出高滴度的病毒颗粒,成功建立稳定株,且在一定范围内稳定株细胞的荧光素酶活性与细胞数目成正比。结论:成功建立了miRNA靶基因高通量筛选系统;利用本筛选系统,成功筛选出靶向细胞周期调控基因P21(CIP1/WAF1)的miRNA。

This study was aimed to establish a high-throughput luciferase reporter system, through which to screen and identify iniRNAs directly targeting p21, and to explore the biological function and significance of these miRNAs. Molecular cloning technique was used to construct and identify two lentivirus-expressing vectors-pWPXL-Luc and pWPXL-Luc-P21-3＇UTR, virus particles were collected after the pWPXL-Luc or pWPXL-Luc-P21-3＇UTR vectors were co-transfected with the psPAX2 packaging plasmid and the envelope plasmid pDM2G into HEK-293T cells. Furthermore, two stable cell lines expressing luciferase singly or co-expressed luciferase and P21-3 ＇UTR were established by transducing HEK-293 cells with recombinant lentivirus ; the former was used as control in the following experiments. Finally luciferase activity of the latter stable cells was measured by using the luciferase reporter assay system. The results showed that high-titre recombinant lentivirus was produced and two stable cell lines were constructed, also to some certain, the luciferase activity was in direct proportion to the number of cells. In conclusion, the high-throughput luciferase reporter system is established successfully; using this system, the 28 miRNA that directly target P21 Cipl/ Wafl are screened experimentally.