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Development of a Hepatitis B Virus Reporter System to Monitor the Early Stages of the Replication Cycle
09:35

Development of a Hepatitis B Virus Reporter System to Monitor the Early Stages of the Replication Cycle

Published on: February 1, 2017

Replication of the hepatitis B virus requires a calcium-dependent HBx-induced G1 phase arrest of hepatocytes

Tricia L Gearhart1, Michael J Bouchard

  • 1Graduate Program in Molecular and Cellular Biology and Genetics, Drexel University College of Medicine, Philadelphia, PA 19102, USA.

Virology
|August 20, 2010
PubMed

Chronic HBV infections cause hepatocellular carcinoma (HCC). Activities of the HBV HBx protein regulate HBV replication and may contribute to the development of HCC. We previously reported that HBx causes primary rat hepatocytes to exit G0 but stall in G1 phase of the cell cycle; entry into G1 stimulated HBV replication. We now report that the activity of the mitochondria permeability transition pore is required for HBx regulation of cell cycle proteins and HBV replication in primary rat hepatocytes, that progression from G0 to G1 stimulates HBV polymerase activity, and that HBV replication is facilitated by the HBx-induced G1 arrest. HBx stimulation of HBV replication was linked to elevation of the R2 subunit of ribonucleotide reductase. Our studies suggest that HBx uses mitochondrial-dependent calcium signaling to cause hepatocytes to exit G0 but stall in G1 and that this HBx activity alters the cellular environment and stimulates HBV replication.

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