• Journal of Applied Biological Chemistry
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• 제59권1호
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• pp.25-29
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• 2016

B형 간염 바이러스는 간경변증과 간세포암의 원인이 되는 간섬유화를 유발한다. 하지만 현재까지 그와 관련한 자세한 메커니즘은 밝혀지지 않았기에 본 연구에서 이를 알아보고자 하였다. 실험 결과, B형 간염 바이러스에서 발현되는 HBx 단백질에 의해 vimentin, fibronectin, slug, snail, NOX4가 증가되는 것을 확인하였다. NOX4에 의한 활성산소가 snail, slug 발현을 유도하고 섬유화 과정을 촉진할 수 있기 때문에 NOX4의 발현을 유도하는 HBx가 간섬유화를 조절, 유도하는 것을 확인하였다.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1993년도 제1회 추계심포지움 and 제2회 생리분자과학연구센터워크숍
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• pp.39-40
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• 1993

Hepatitis B virus (HBV)is a member of the Hepadna virus family whose members share a characteristic virion structure and genome size, around 3.2kb in a paritially double-stranded form. The genome of HBV contains four overlapping open reading frames designated as P(polymerase). C(core), S(surface antigen)and X. The X gene has potential to encode 154 amino acids protein.

• IMMUNE NETWORK
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• 제3권1호
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• pp.23-28
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• 2003

Background: Intracellular antibody specific to hepatitis B virus X protein (HBx) might be useful for studying the role of HBx in hepatocellular carcinogenesis and HBV replication. Methods: With variable region genes for H7 monoclonal anti-HBx Ab, we constructed a vector for bacterial expression of single chain Ab (scFv) and a vector for eukaryotic cell expression of it. The expression of H7 scFv and its binding activity against HBx was examined by immunoblotting and immunofluorescence microscopy. Results: H7 scFv expressed in bacterial cells retained reactivity to HBx. We demonstrated its intracytoplasmic expression in CosM6 eukaryotic cells. Conclusion: This is the first study showing the expression of intracellular anti-HBx Ab in eukaryotic cells. H7 scFv may be a good tool to study the function of HBx in HBV infection.

• 한국생명과학회:학술대회논문집
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• 한국생명과학회 2003년도 제39회 학술심포지움
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• pp.144-144
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• 2003

• BMB Reports
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• 제32권6호
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• pp.521-528
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• 1999

The folding of recombinant hepatitis B virus X-protein (rHBx) solubilized from Escherichia coli inclusion bodies was investigated. By sequential dialysis of urea, rHBx was folded into its native structure, which was demonstrated by the efficacy of its transcriptional activation of the adenovirus major late promoter (MLP), fluorescence spectroscopy, and circular dichroism (CD) analysis. The decrease in CD values at 220 nm and a corresponding blue shift of the intrinsic fluorescence emission confirmed the ability of rHBx to refold in lower concentrations of urea, yielding the active protein. Equilibrium and kinetic studies of the refolding of rHBx were carried out by tryptophan fluorescence measurements. From the biphasic nature of the fluorescence curves, the existence of stable intermediate states in the renaturation process was inferred. Reverse phase-high performance liquid chromatography (RP-HPLC) analysis further demonstrated the existence of these intermediates and their apparent compactness.

• 생명과학회지
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• 제17권6호통권86호
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• pp.766-771
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• 2007

B형 간염 바이러스(HBV)와 C형 간염 바이러스(HCV)에 함께 감염되면 단독 감염의 경우보다 더 심각한 간질환이 유발되고 간암으로의 발전 가능성도 높아진다. 본 연구에서는 HBV의 X단백질(HBx)과 HCV의 코어 단백질이 인간 간암세포주인 HepG2세포에서 p53의 양을 협조적으로 증가시킨다는 것을 보여 주었다. 이로 인하여 세포예정사를 촉진하는 Bax 단백질의 발현이 더 증가하는 반면에 세포예정사를 억제하는 Bcl2의 발현은 더 억제됨이 관찰되었다. 그러나 이러한 효과들은 p53-음성인 Hep3B 세포에서는 관찰되지 않았다. 나아가 HBx와 코어 단백질은 HepG2의 cisplatin-매개성 세포예정사를 협조적으로 증가시키는 반면에 Hep3B에서는 이러한 효과가 나타나지 않았다. 이러한 연구 결과들은 HBV와 HCV가 동시에 감염되었을 경우에 나타나는 임상적인 소견을 이해하고 세포예정사에 미치는 HBx와 코어 단백질의 영향에 대한 기존의 상충적인 연구결과들을 해석하는데 도움을 줄 수 있다.

• Bulletin of the Korean Chemical Society
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• 제26권9호
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• pp.1385-1389
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• 2005

Human hepatitis B virus (HBV) is a pathogen related to the development of liver diseases including chronic hepatitis, cirrhosis, and hepatocellular carcinoma (HCC). However, the efficient methods to suppress HBV replication have not been developed yet. Therefore, we have used RNA interference (RNAi) as a potential tool for the suppression of HBV replication. Here, we designed a 21 nt small intefering dsRNA (siRNA) against hepatitis B virus X (HBx) RNA with 3' overhanging ends derived from T7 promoter. It has been reported that HBV X protein plays an important role in HBV gene expression and viral replication. The suppression of HBx gene expression by the 21 nt siRNA was investigated by Northern blot analysis and chloramphenicol acetyl transferase (CAT) assay. The level of HBx mRNA was decreased by siRNA in a dose-dependent manner. We also found that the 21 nt siRNA inhibited the HBV replication in hepatocellular carcinoma cell.

• 한국미생물학회:학술대회논문집
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• 한국미생물학회 1999년도 제39회 춘계학술발표대회
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• pp.23-26
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• 1999

• Journal of Microbiology
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• 제43권6호
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• pp.529-536
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• 2005

Viral infection causes stress to the endoplasmic reticulum (ER). The response to endoplasmic reticulum stress, known as the unfolded protein response (UPR), is designed to eliminate misfolded proteins and allow the cell to recover. The role of hepatitis C virus (HCV) non-structural protein NS4B, a component of the HCV replicons that induce UPR, is incompletely understood. We demonstrate that HCV NS4B could induce activating transcription factor (ATF6) and inositol-requiring enzyme 1 (IRE1), to favor the HCV subreplicon and HCV viral replication. HCV NS4B activated the IRE1 pathway, as indicated by splicing of X box-binding protein (Xbp-1) mRNA. However, transcriptional activation of the XBP-1 target gene, EDEM (ER degradation-enhancing $\alpha-mannosidase-like$ protein, a protein degradation factor), was inhibited. These results imply that NS4B might induce UPR through ATF6 and IRE1-XBP1 pathways, but might also modify the outcome to benefit HCV or HCV subreplicon replication.

• BMB Reports
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• 제29권2호
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• pp.175-179
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• 1996

Viral surface proteins are known to play an essential role in attachment of the virus particle to the host cell membrane. In case of the hepatitis B virus (HBV) several reports have described potential receptors on the target cell side, but no definite receptor protein has been isolated yet. As for the viral side, it has been suggested that the preS region of the envelope protein, especially the preS1 region, is involved in binding of HBV to the host cell. In this study, preS1 region was recombinantly expressed in the form of a maltose binding protein (MBP) fusion protein and used to identify and visualize the expression of putative HBV receptor(s) on the host cell. Using laser scanned confocal microscopy and by FACS analysis, MBP-preS1 proteins were shown to bind to the human hepatoma cell line HepG2 in a receptor-ligand specific manner. The binding kinetic of MBP-preS1 to its cellular receptor was shown to be temperature and time dependent. In cells permeabilized with Triton X-100 and treated with the fusion protein, a specific staining of the nuclear membrane could be observed. To determine the precise location of the receptor binding site within the preS1 region, several short overlapping peptides from this region were synthesized and used in a competition assay. In this way the receptor binding epitope in preS1 was revealed to be amino acid residues 27 to 51, which is in agreement with previous reports. These results confirm the significance of the preS1 region in virus attachment in general, and suggest an internalization pathway mediated by direct attachment of the viral particle to the target cell membrane.