ABSTRACT
Objective To construct the recombinant adeno-associated virus vector carrying cancerous inhibitor of PP2A (CIP2A)short hairpin RNA (shRNA)for preparation of high-titer viruses.Methods The small hairpin RNA of CIP2A (CIP2A shRNA)was designed,synthesized and cloned into pDC31 6-EGFP-U6 plasmid which was double digested by Bam HⅠ and Hin dⅢ.The resultant plasmid pDC31 6-EGFP-shRNA was confirmed and served as template to appraise primers.EGFP-CIP2A shRNA sequence was amplified by PCR,double digested with Eco RⅠand Sal Ⅰ and ligated to pSNAV2.0 plasmid digested with the same enzyme pair.pSNAV2.0-EGFP-CIP2A shRNA plasmid DNA was prepared,purified,identified and transfected into BHK-21 cells.BHK-21 cells expressing CIP2A shRNA (BHK-21/CIP2A-shRNA ) were obtained and subsequently infected with VGTC’s proprietary AAV packaging system to package the rAAV2-CIP2A shRNA.After purification,the functional and infectious virus was obtained and the titer of virus was detected.Real-time PCR and Western blot methods were used to detect the expression of CIP2A after infection with HepG2 cells,and the empty viral vector rAAV2-EGFP was used as control. Results A recombinant adeno-associated virus-2 vector carrying CIP2A shRNA was constructed successfully.The presence of the target sequence in the vector was confirmed by double enzyme digestion and sequencing.By transfecting the pSNAV2.0-EGFP-CIP2A shRNA plasmid into BHK-21 cells,BHK-21/CIP2A shRNA cells were infected with helper virus HSV1-rc/ΔUL2 to package the rAAV2-CIP2A shRNA to obtain a functional and infectious virus.The titer of the recombinant virus was 0.25×10 1 2 v.g./mL.The expression of CIP2A mRNA and screening value of 1×10 5 MOI effected HepG2 cells.Conclusion A high-titer recombinant adeno-associated virus-2 vector carrying CIP2A shRNA has been constructed successfully.