Different Regions of Hepatitis B Virus X Protein Are Required for Enhancement of bZip-Mediated Transactivation versus Transrepression

@article{Barnabas2000DifferentRO,
  title={Different Regions of Hepatitis B Virus X Protein Are Required for Enhancement of bZip-Mediated Transactivation versus Transrepression},
  author={Sangeeta Barnabas and Ourania M Andrisani},
  journal={Journal of Virology},
  year={2000},
  volume={74},
  pages={83 - 90}
}
ABSTRACT The hepatitis B virus X protein (pX) interacts directly with the bZip transactivator CREB and the bZip repressors ICERIIγ and ATF3, increasing their DNA-binding affinity in vitro and their transcriptional efficacy in vivo. However, the mechanism of bZip-pX interaction and of the pX-mediated increase in the bZip transcriptional efficacy remains to be understood. In this study with deletion mutants of pX, we delineated a 67-amino-acid region spanning residues 49 to 115 required for… Expand
A Carboxy-terminal Region of the Hepatitis B Virus X Protein Promotes DNA Interaction of CREB and Mimics the Native Protein for Transactivation Function
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An internal segment (residues 58–119) of the hepatitis B virus X protein is sufficient to activate MAP kinase pathways in mouse liver
TLDR
These findings provide the first evidence for the requirement of domain 58–119 of HBx in transmitting mitogenic signals to the nucleus in vivo. Expand
The Mitogenic Function of Hepatitis B Virus X Protein Resides within Amino Acids 51 to 140 and Is Modulated by N- and C-Terminal Regulatory Regions
TLDR
The pX deletion analysis demonstrates that WT pX function is modulated by two regions spanning amino acids 1 to 78 and 141 to 154, suggesting that increased stability of naturally occurring pX variants lacking amino acids 134 to 154 may play a role in HCC development. Expand
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TLDR
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TLDR
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TLDR
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TLDR
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TLDR
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TLDR
While the X protein is not absolutely essential for HBV replication or its maturation in transgenic mice, it can enhance viral replication, apparently by activating viral gene expression. Expand
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