[Synergetic transactivating effect of HCV core and HBV X proteins on SV40 early promoter/enhancer].
BACKGROUND
To investigate the synergetic transactivating effects of HCV core and HBV X proteins.


METHODS
HCV core and HBV X protein-expressing plasmids were constructed with the vector pcDNA3.1(-). The plasmids were transfected into HepG2 cells and cotransfected Hep2 cells with reporter plasmid Psv-lacZ by lipofectamine plus reagents. The virus proteins produced in transient expression system were detected at the transcription and translation levels. The activity of b-galactosidase was detected, which reflected the transactivating function of the proteins.


RESULTS
The expression of plasmids were detected in soluble protein cell extracts of transiently transfected HepG2 cells. HCV core protein activated the b-galactosidase expression at a value 4.9 times higher than the control, while HBV X protein activated at a value 3.5 times. It arrived at 9 times transfected with the plasmids simultaneously. The activating effect increased in relation to the amount of plasmids.


CONCLUSIONS
The results suggested that the two kinds of virus proteins have transactivating effect on SV40 early promoter/enhancer, and they acted synergistically. These contribute to explain the mechanisms of liver injury or tumorigenesis induced by HCV or/and HBV infection.
Liu
Yan
Y
Gene Therapy Research Center, Institute of Infectious Diseases, The 302nd Hospital, Beijing 100039, China.
Cheng
Jun
J
Shao
De-zhi
DZ
Wang
Lin
L
Zhong
Yan-wei
YW
Dong
Jing
J
Li
Ke
K
Li
Li
L
D000818:Animals; D006528:Carcinoma, Hepatocellular / Q000821:virology; D004742:Enhancer Elements, Genetic; D016174:Hepacivirus / Q000235:genetics; D018936:Hepatitis C Antigens / Q000235:genetics; D006801:Humans; D008113:Liver Neoplasms / Q000821:virology; D011401:Promoter Regions, Genetic / Q000187:drug effects; D013539:Simian virus 40 / Q000235:genetics*; D015534:Trans-Activators / Q000235:genetics*; D015533:Transcriptional Activation; D014758:Viral Core Proteins / Q000235:genetics*; D054334:Viral Regulatory and Accessory Proteins; D001616:beta-Galactosidase / Q000096:biosynthesis / Q000235:genetics
D018936:Hepatitis C Antigens; D015534:Trans-Activators; D014758:Viral Core Proteins; D054334:Viral Regulatory and Accessory Proteins; C057628:hepatitis B virus X protein; C069130:nucleocapsid protein, Hepatitis C virus; D001616:beta-Galactosidase