[Activating effect of hepatitis B virus preS/S protein on proliferating cell nuclear antigen gene promoter].
BACKGROUND
PreS/S gene was derived from hepatitis B virus (HBV) integration fragment of human hepatocellular carcinoma genome, containing the promoter of preS/S and the C terminal truncated preS/S open reading frame. PreS/S protein may have important roles in processing hepatoma in some HBV-infected patients. The aim of the study was to study the activity of HBV preS/S protein on proliferating cell nuclear antigen (PCNA) promoter and to localize compartment of the preS/S protein in the liver cell line L02.


METHODS
The authors studied the effect of the 3 -truncated preS/S on human PCNA promoter by co-transfecting the expression plasmids of luciferase reporter gene, used the immunohistochemical method to localize the preS/S protein.


RESULTS
The expression product of the plasmid, pKSH7C-HpaI which contained the 3 -truncated preS/S and the flanking cellular sequences, stimulated the expression of PCNA promoter dose dependently,and its effect was 0.5 folds higher than control. Immunohistochemistry showed that the preS/S protein located in the cytosolic region of the liver cell line L02.


CONCLUSIONS
The HBV preS/S protein could stimulate the PCNA promoter of the liver cell, its effect was not direct, which suggests that the effect of preS/S protein on PCNA promoter was probably through the cell signal transduction pathway.
Yan
Pei-jun
PJ
Department of Biochemistry and Cell Biology, Shanghai Medical College, Fudan University, Shanghai 200032 China.
Wang
Lei
L
Zha
Xi-liang
XL
Lu
Chang-de
CD
D006528:Carcinoma, Hepatocellular / Q000235:genetics / Q000821:virology; D006514:Hepatitis B Surface Antigens / Q000235:genetics*; D006515:Hepatitis B virus / Q000235:genetics*; D006801:Humans; D008113:Liver Neoplasms / Q000235:genetics / Q000821:virology; D018809:Proliferating Cell Nuclear Antigen / Q000235:genetics*; D011401:Promoter Regions, Genetic; D011498:Protein Precursors / Q000235:genetics*; D014407:Tumor Cells, Cultured; D016662:Virus Integration
D006514:Hepatitis B Surface Antigens; D018809:Proliferating Cell Nuclear Antigen; D011498:Protein Precursors; C050806:presurface protein 1, hepatitis B surface antigen