多核酶表达系统在HEK293细胞中对多药耐药相关蛋白(MRP1)的表达抑制作用(英文)

EXPRESSION INHIBITION OF MULTIDRUG RESISTANCE-ASSOCIATED PROTEIN(MRP1) BY MULTI-RIBOZYME EXPRESSION SYSTEM IN HEK293 CELLS

为了研究多核酶表达系统在HEK293细胞中对多药耐药相关蛋白表达抑制的作用,我们构建了含有20个可以自身切割的顺式作用核酶和10个靶向MRP1基因特定位点的反式作用核酶的多核酶表达系统。利用RT-PCR、Western blot和MTT分析了多核酶系统分别与MRP1靶基因质粒和MRP1全长基因质粒共转染的HEK293细胞。结果显示,多核酶表达系统能够明显降低荧光融合蛋白在HEK293细胞中的表达。RT-PCR分析表明,MRP1靶mRNA降低程度与多核酶表达系统所含的反式作用核酶数目有关。Western blot分析显示了与RT-PCR相似的结果。MTT分析表明,多核酶表达系统能够逆转由MRP1基因转染HEK293细胞产生的多药耐药性。结果提示,含有多个核酶的表达系统对MRP1基因的抑制效应优于单核酶的表达系统。因此,该策略可能用于基因治疗肿瘤或其他疾病。

To study application of multi-ribozyme expression system on expression inhibition of multidrug resistance-associated protein （MRP1） in HEK293 cells, the multi-ribozyme expression system containing 20 cis-acting ribozymes for self-cleavage and 10 trans-acting ribozymes for targeting to MRP1 gene specific site were constructed. HEK293 cells cotransfeeted multi-ribozyme expression system with MRP1 target gene or full length of MRP1 gene respectively were analyzed by RT-PCR, Western blot analysis and MTT assay. The results showed that multi-ribozyme systems were able to dramatically decrease fluorescent fusion protein expression in HEK293 cells. RT-PCR analysis indicated that the extent of MRP1 target mRNA decrease was correlated with the number of trans-acting ribozyme contained in multi-ribozyme expression system. Similar changes have been observed from Western blot. MTT assay showed that muhi-ribozyme systems were able to reverse MDR generated by MRP1 gene in HEK cells. These results suggested that inhibitory effects of multiple copies of ribozymes contained in the system were better than that of single ribozyme contained. There- fore, this strategy could be used in treatment of tumor or other diseases via gene therapy.