n-Butyrate, a cell cycle blocker, inhibits early amplification of duck hepatitis B virus covalently closed circular DNA after in vitro infection of duck hepatocytes.

Published

Journal Article

During chronic hepadnavirus infection, virus persistence depends on the regulation of the pool of covalently closed circular DNA (cccDNA), which is the template for transcription of viral RNA species. The development of in vitro infection of duck hepatocyte primary cultures by duck hepatitis B virus (DHBV) provides a unique opportunity to study the regulation of cccDNA synthesis. After DHBV in vitro infection, cccDNA is detected 1 day later and is amplified to a high copy number after 1 week in culture. We studied whether this amplification occurs during cell cycle progression of duckling hepatocytes. By using [3H]thymidine incorporation, we found that hepatocytes obtained from 3-week-old ducklings spontaneously entered the S phase of the cell cycle when cultured in serum-free medium without added growth factors. Bromodeoxyuridine labeling confirmed that cellular DNA synthesis took place in more than 50% of parenchymal cells. Cytofluorometry analysis revealed the presence of asynchronous populations and polyploidization processes. The addition of a cell cycle blocker, n-butyrate, completely inhibited [3H]thymidine incorporation and blocked duckling hepatocytes in the G1 phase of the cell cycle. Simultaneously, butyrate inhibited cccDNA amplification and allowed the establishment of DHBV infection, as demonstrated by the detection of a basal level of cccDNA in treated hepatocytes. Both effects were reversible since active cell DNA synthesis was restored and cccDNA accumulated after drug withdrawal.

Full Text

Duke Authors

Cited Authors

  • Turin, F; Borel, C; Benchaib, M; Kay, A; Jamard, C; Guguen-Guillouzo, C; Trépo, C; Hantz, O

Published Date

  • May 1996

Published In

Volume / Issue

  • 70 / 5

Start / End Page

  • 2691 - 2696

PubMed ID

  • 8627742

Pubmed Central ID

  • 8627742

International Standard Serial Number (ISSN)

  • 0022-538X

Language

  • eng

Conference Location

  • United States