Up-regulating effect of hepatitis C virus core protein on inducible nitric oxide synthase gene promoter / 中华传染病杂志

ABSTRACT

Objective To investigate the transactivating effect of hepatitis C virus(HCV)core protein on inducible nitric oxide synthase(iNOS)gene promoter and the molecular biological mecha- nisms of HCV pathogenesis.Methods Polymerase chain reaction(PCR)technique was employed to amplify the sequence of iNOS promoter by using HepG2 genomic DNA as template,and the product was cloned into pGEM-T vector.The iNOSp gene was cut from T-iNOSp by KpnⅠand XhoⅠ,and then was cloned into pCAT3-Basic,the constructed vector was named as pCAT3-iNOSp,pCAT3-iN- OSp was transfected into the LO_2 cell line.LO_2 cell was also cotransfected with pcDNA3.1(-)-core and pCAT3-iNOSp by FuGENE 6 transfection reagents.The LO_2 cells transfected with pCAT3-Basic was used as negative control.The activity of CAT in LO_2 cells was detected by an ELISA kit after 48 hours,which reflected the transactivating function of HCV core protein to iNOS gene promoter.Re- sults The expressive vector pcDNA3.1(-)-core and report vector pCAT3-iNOSp had been construc- ted and confirmed by restriction enzyme digestion and sequencing.The expression of CAT in LO_2 cells transfected with pCAT3-iNOSp and peDNA3,1(-)-core was 11 times as higher as that of pCAT3-bas- ic,and 6 times as higher as that of pCAT3-iNOSp.Conclusion It is suggested that HCV core protein can transactivate iNOS gene promoter.