Figure 1

Construction of recombined plasmids containing siMDR1 and inhibition of endogenous MDR1 gene expression. (A) Identification of recombinant pSEB-siMDR1 plasmids by PCR amplification, About 300 bp of DNA fragment was PCR amplified from pSEB-siMDR1 plasmid template by U6 promoter primer and antisense of siRNA sequence. (1. negative control; 2. PCR product from pSEB-siMDR1-1 plasmid; 3. PCR product from pSEB-siMDR1-2 plasmid; 4. PCR product from pSEB-siMDR1-3 plasmid; 5. PCR product from pSEB-siMDR1-4 plasmid; 6. DNA Ladder, 600 bp, 500 bp, 400 bp, 300 bp, 200 bp, 100 bp). (B) Identification of recombinant pSEB-siMDR1 plasmids by Not I restriction enzyme digestion, No small DNA fragment was digested from corrected recombinant pSEB-siMDR1 plasmids by Not I enzyme compared with pSEB-HUS vehicle vector (7. Not Ienzyme-digested pSEB-HUS vehicle vecter; 8. Not Ienzyme-digested pSEB-siMDR1-1 plasmid; 9. Not Ienzyme-digested pSEB-siMDR1-2 plasmid; 10. Not Ienzyme-digested pSEB-siMDR1-3 plasmid; 11. Not Ienzyme-digested pSEB-siMDR1-4 plasmid;12. λ/HindIII DNA Ladder, 23130 bp, 9416 bp, 6557 bp, 4361 bp, 2322 bp, 2027 bp, 564 bp, 125 bp), (C) Silencing efficiency of MDR1 expression by siMDR1, Expression of MDR1 in L2-RYC cells with pSEB-siMDR1 plasmids lipofection for 24 hr was detected by real-time PCR. Results were normalized by GAPDH and confirmed in at least three batches of independent experiments. (*P < 0.05, vs other four single siMDR1 transfection groups and control group).