Synergetic transactivating functions of HCV core and truncated HBV middle surface protein / 中华肝脏病杂志

ABSTRACT

<p><b>OBJECTIVE</b>To investigate the synergetic transactivating functions of HCV core and truncated HBV middle surface proteins.</p><p><b>METHODS</b>Two recombinant expression plasmids harboring HCV core and C-terminally truncated HBV middle surface protein gene were constructed, respectively. The plasmids were transfected into HepG2 cells and cotransfected HepG2 cells with reporter plasmid pSV-lacZ by lipofectamine plus reagents. The transient expressed viral proteins were identified at the transcription and translation levels. The activity of beta-galactosidase was detected, which reflected the transactivating function of the proteins.</p><p><b>RESULTS</b>The protein expression of plasmids was detected in soluble cell extracts of transiently transfected HepG2 cells. HCV core protein activated the beta-galactosidase expression at a value of 4.6 times higher than the control, while C-terminally truncated HBV middle surface protein activated at a value of 3.2 times. It reached 8.4 times transfected with the plasmids simultaneously. The transactivating effect was dose dependent.</p><p><b>CONCLUSIONS</b>It is suggested that the two kinds of virus proteins have transactivating effect on SV40 early promoter/enhancer, and they act synergistically. These contribute to explain the mechanisms of liver injury or tumorigenesis induced by HCV or/and HBV infection.</p>