Construction and identification of RNAi eukaryotic expression vectors targeting human transcription factor glioma-associated oncogene homolog 1 / 中华胰腺病杂志

ABSTRACT

Objective To construct RNAi eukaryotic expressing vectors of human transcription factor glioma-associated oncogene homolog 1 (GLI1) with pGCsi-U6-GFP plasmid and to identify its activity in interfering GLI1.Methods Three GLI1siRNA targeting GLI1 were designed and synthesized according to the GLI1cDNA sequence in GeneBank,and then were cloned into pGCsi-U6-GFP to construct the recombinant plasmids,and transformed into E.coli DH5a,then it was amplified and plasmids were extracted,which were further confirmed by PCR reaction and DNA sequencing,pGCsi-U6-siRNA-C was negative as control wector.Then recombinant plasmids pGCs-U6-GLI1siRNA-1,pGCs-U6-GLI1 siRNA-2,pGCs-U6-GLI1siRNA-3 pGCsi-U6-siRNA-C and a eukaryotic over-expression vector pEGFP-N1-GLI1 were co-transfected into HEK293 cells by Lipofectamine 2000 respectively.The ceils were collected at 48 h after transfection.Semi-quantitative RTPCR and Western Blot were performed to detect the expression of GLI1 mRNA and protein to screen the optimal vector which had the best interfering effect.Results A 369 bp fragment was amplified from all three recombinant plasmids,(pGCs-U6-GLI1 siRNA-1,pGCs-U6-GLI1 siRNA-2,pGCs-U6-GLIlsiRNA-3),showing that synthesized shRNA oligonucleotide fragments were correctly inserted into three recombinant plasmids,which were further confirmed by sequencing.Expression levels of GLIlmRNA and protein in cells in pGCs-U6-GLI1 siRNA-1,pGCs-U6-GLI1 siRNA-2,pGCs-U6-GLI1 siRNA-3 were 0.290 ± 0.011,0.421 ± 0.018,0.373 ±0.018,and 0.318 ± 0.026,0.443 ± 0.021,0.381 ± 0.018,which were significantly lower than those in negative control group (0.834 ± 0.022,0.818 ± 0.024,P =0.000),the inhibitory rates were 65.8 ％,50.7％,55.7％,and 63.9％,48.3％,53.9％.The interfering efficacy of pGCs-U6-GLIlsiRNA-1 was the strongest among the three recombinant plasmids.Conclusions RNAi eukaryotic vectors pGCs-U6-GLIlsiRNA-1,pGCs-U6-GLI1 siRNA-2,pGCs-U6-GLI1 siRNA-3 are successfully constructed and the optimal vector is identified,and this can provide a solid experimental foundation for further functional study of GLI1 gene.