This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrowReprints and Permissions
Right arrow Copyright Information
Right arrow Books from ASM Press
Right arrow MicrobeWorld
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Mabit, H.
Right arrow Articles by Schaller, H.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Mabit, H.
Right arrow Articles by Schaller, H.

 Previous Article  |  Next Article 

Journal of Virology, December 2000, p. 11472-11478, Vol. 74, No. 24
0022-538X/00/$04.00+0
Copyright © 2000, American Society for Microbiology. All rights reserved.

Intracellular Hepadnavirus Nucleocapsids Are Selected for Secretion by Envelope Protein-Independent Membrane Binding

Hélène Mabitdagger and Heinz Schaller*

Zentrum für Molekulare Biologie Heidelberg, 69120 Heidelberg, Germany

Received 15 May 2000/Accepted 19 September 2000

Hepadnaviruses are DNA viruses but, as pararetroviruses, their morphogenesis initiates with the encapsidation of an RNA pregenome, and these viruses have therefore evolved mechanisms to exclude nucleocapsids that contain incompletely matured genomes from participating in budding and secretion. We provide here evidence that binding of hepadnavirus core particles from the cytosol to their target membranes is a distinct step in morphogenesis, discriminating among different populations of intracellular capsids. Using the duck hepatitis B virus (DHBV) and a flotation assay, we found about half of the intracellular capsids to be membrane associated due to an intrinsic membrane-binding affinity. In contrast to free cytosolic capsids, this subpopulation contained largely mature, double-stranded DNA genomes and lacked core protein hyperphosphorylation, both features characteristic for secreted virions. Against expectation, however, the selective membrane attachment observed did not require the presence of the large DHBV envelope protein, which has been considered to be crucial for nucleocapsid-membrane interaction. Furthermore, removal of surface-exposed phosphate residues from nonfloating capsids by itself did not suffice to confer membrane affinity and, finally, hyperphosphorylation was absent from nonenveloped nucleocapsids that were released from DHBV-transfected cells. Collectively, these observations argue for a model in which nucleocapsid maturation, involving the viral genome, capsid structure, and capsid dephosphorylation, leads to the exposure of a membrane-binding signal as a step crucial for selecting the matured nucleocapsid to be incorporated into the capsid-independent budding of virus particles.


* Corresponding author. Mailing address: Zentrum für Molekulare Biologie Heidelberg, Im Neuenheimer Feld 282, D-69120 Heidelberg, Germany. Phone: 49-6221-54-68-85. Fax: 49-6221-54-58-93. E-mail: hshd{at}zmbh.uni-heidelberg.de

dagger Present address: Zoologisches Institut, 8057 Zürich, Switzerland.


Journal of Virology, December 2000, p. 11472-11478, Vol. 74, No. 24
0022-538X/00/$04.00+0
Copyright © 2000, American Society for Microbiology. All rights reserved.



This article has been cited by other articles:

  • Lambert, C., Doring, T., Prange, R. (2007). Hepatitis B Virus Maturation Is Sensitive to Functional Inhibition of ESCRT-III, Vps4, and {gamma}2-Adaptin. J. Virol. 81: 9050-9060 [Abstract] [Full Text]  
  • Schormann, W., Kraft, A., Ponsel, D., Bruss, V. (2006). Hepatitis B virus particle formation in the absence of pregenomic RNA and reverse transcriptase.. J. Virol. 80: 4187-4190 [Abstract] [Full Text]  
  • Khan, N., Guarnieri, M., Ahn, S. H., Li, J., Zhou, Y., Bang, G., Kim, K.-H., Wands, J. R., Tong, S. (2004). Modulation of Hepatitis B Virus Secretion by Naturally Occurring Mutations in the S Gene. J. Virol. 78: 3262-3270 [Abstract] [Full Text]  
  • Ostrow, K. M., Loeb, D. D. (2004). Underrepresentation of the 3' Region of the Capsid Pregenomic RNA of Duck Hepatitis B Virus. J. Virol. 78: 2179-2186 [Abstract] [Full Text]  
  • Kock, J., Kann, M., Putz, G., Blum, H. E., von Weizsacker, F. (2003). Central Role of a Serine Phosphorylation Site within Duck Hepatitis B Virus Core Protein for Capsid Trafficking and Genome Release. J. Biol. Chem. 278: 28123-28129 [Abstract] [Full Text]  
  • Mabit, H., Knaust, A., Breiner, K. M., Schaller, H. (2003). Nuclear Localization of the Duck Hepatitis B Virus Capsid Protein: Detection and Functional Implications of Distinct Subnuclear Bodies in a Compartment Associated with RNA Synthesis and Maturation. J. Virol. 77: 2157-2164 [Abstract] [Full Text]  
  • Ponsel, D., Bruss, V. (2002). Mapping of Amino Acid Side Chains on the Surface of Hepatitis B Virus Capsids Required for Envelopment and Virion Formation. J. Virol. 77: 416-422 [Abstract] [Full Text]  
  • Chapdelaine, Y., Kirk, D., Karsies, A., Hohn, T., Leclerc, D. (2002). Mutation of Capsid Protein Phosphorylation Sites Abolishes Cauliflower Mosaic Virus Infectivity. J. Virol. 76: 11748-11752 [Abstract] [Full Text]  
  • Maillard, P., Krawczynski, K., Nitkiewicz, J., Bronnert, C., Sidorkiewicz, M., Gounon, P., Dubuisson, J., Faure, G., Crainic, R., Budkowska, A. (2001). Nonenveloped Nucleocapsids of Hepatitis C Virus in the Serum of Infected Patients. J. Virol. 75: 8240-8250 [Abstract] [Full Text]  
  • Sprinzl, M. F., Oberwinkler, H., Schaller, H., Protzer, U. (2001). Transfer of Hepatitis B Virus Genome by Adenovirus Vectors into Cultured Cells and Mice: Crossing the Species Barrier. J. Virol. 75: 5108-5118 [Abstract] [Full Text]  
  • Mabit, H., Breiner, K. M., Knaust, A., Zachmann-Brand, B., Schaller, H. (2001). Signals for Bidirectional Nucleocytoplasmic Transport in the Duck Hepatitis B Virus Capsid Protein. J. Virol. 75: 1968-1977 [Abstract] [Full Text]