Up-regulation of thioredoxin reductase 1 gene promoter by hepatitis B virus pre-S2 protein / 解放军医学杂志

ABSTRACT

Objective To investigate the activity of HBV pre-S2 protein on thioredoxin reductase 1 (TXNRD1) gene promoter. Methods TXNRD1 gene promoter DNA sequence was identified in GenBank by bioinformatics and amplified from HepG2 genome by polymerase chain reaction (PCR). The amplified product was cloned into pCAT3-Basic reporter vector,named pCAT3-TXNRD1p. The HepG2 cells were transfected by pCAT3-TXNRD1p,and then co-tranfected by pCAT3-TXNRD1p and pcDNA3.1(-)-preS2 plasmids. The choloraphenical acetyltransferase(CAT)activity was assessed by enzyme linked immunosorbent assay(ELISA). Results The results indicate that HepG2 cells transfected by pCAT3-TXNRD1p had higher activity of CAT than that transfected by pCAT3-Basic. The expression of CAT in HepG2 cells co-transfected by pCAT3-TXNRD1p and pcDNA3.1(-)-preS2 was 2.2 times higher than that with pCAT3-TXNRD1p. Conclusions The TXNRD1 gene promoter identified in this study has transcription activity and HBV pre-S2 protein can transactivate the expression of TXNRD1 gene.