[The effects of different PAP domains on hepatitis B virus replication].
OBJECTIVE
To investigate the effects of different PAP domains on hepatitis B virus replication.


METHODS
The full length and two truncated PAP mutants were cloned into a eukaryotic expression plasmid, and were transfected into HepG2.2.15 cells using lipofectamine 2000. 3 days after transfection, the medium and cells were collected. HBsAg and HBeAg were measured using ELISA. The titers of HBV DNA were quantified using fluorogenic quantitative PCR (FQ-PCR). HepG2 cells were used to determine the cytotoxicity of the plasmids transfection by MTT assays.


RESULTS
The inhibitory effect on HBV replication of the C-terminal 25 amino acids deleted PAP mutant (pXF3H-PAP14) was not significantly different from that of the full length PAP (pXF3H-PAP12) (Chi-square test = 0.5, 2.0, 0.02, probability value more than 0.05), however, the cytotoxicity of pXF3H-PAP14 was lower than that of pXF3H-PAP12 (Chi-square test = 7.7, probability value less than 0.01). Both N-terminal 69 amino acids deleted mutant and C-terminal 25 amino acids deleted mutant had no cytotoxicity and no antiviral activity.


CONCLUSIONS
C-terminal 25 amino acid of PAP is related to cytotoxicity but not related to antiviral activity of PAP. N-terminal 69 amino acid of PAP is related to the anti-HBV effect of PAP.
Guo
Chun-xia
CX
Department of Infectious Disease, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China.
He
Yong-wen
YW
Peng
Cheng
C
Lei
Yan-chang
YC
Li
Wen-ting
WT
D000595:Amino Acid Sequence; D000998:Antiviral Agents / Q000494:pharmacology*; D015153:Blotting, Western; D004279:DNA, Viral / Q000187:drug effects / Q000378:metabolism; D056945:Hep G2 Cells; D006514:Hepatitis B Surface Antigens / Q000378:metabolism; D006513:Hepatitis B e Antigens / Q000378:metabolism; D006515:Hepatitis B virus / Q000187:drug effects / Q000235:genetics / Q000502:physiology*; D006801:Humans; D008081:Liposomes; D010957:Plasmids / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D054789:Ribosome Inactivating Proteins, Type 1 / Q000235:genetics* / Q000378:metabolism / Q000494:pharmacology*; D017384:Sequence Deletion; D014162:Transfection; D014779:Virus Replication / Q000187:drug effects*
D000998:Antiviral Agents; D004279:DNA, Viral; D006514:Hepatitis B Surface Antigens; D006513:Hepatitis B e Antigens; D008081:Liposomes; D054789:Ribosome Inactivating Proteins, Type 1; C024275:pokeweed antiviral protein