The Role of the HBV Envelope Proteins in the HDV Replication Cycle
The hepatitis delta virus (HDV) is a subviral agent that utilizes the envelope proteins of the hepatitis B virus (HBV) for propagation. When introduced into permissive cells, the HDV RNA genome replicates and associates with multiple copies of the HDV-encoded proteins to assemble a ribonucleoprotein (RNP) complex. The mechanism necessary to export the RNP fromthe cell is provided by the HBV envelope proteins, which have the capacity to assemble lipoprotein vesicles that bud into the lumen of a pre-Golgi compartment before being secreted. In addition to allowing the release of the HDV RNP, the HBV envelope proteins also provide a means for its targeting to an uninfected cell, thereby ensuring the spread of HDV. This chapter covers the molecular aspects of the HBV envelope protein functions in the HDV replication cycle, in particular the activity of the small envelope protein in RNP export and the function of the large envelope protein at viral entry.
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- Casey JL, Niro GA, Engle RE, Vega A, Gomez H, McCarthy M, Watts DM, Hyams KC, and Gerin JL (1996). Hepatitis B virus (HBV)/hepatitis D virus (HDV) coinfection in outbreaks of acute hepatitis in the Peruvian Amazon basin: the roles of HDV genotype III and HBV genotype F. J Infect Dis 174:920–926PubMedGoogle Scholar
- Ganem D, and Schneider R (2001). Hepadnaviridae: the viruses and their replication. In Fields Virology DM. Knipe, and P.M. Howley, eds. (Philadelphia, PA, Lippincott Williams & Wilkins), pp. 2923–2969Google Scholar
- Heermann K, and Gerlich W (1992). Surface proteins of hepatitis B viruses. In Molecular Biology of HBV, A. Maclachlan, ed. (Boca Raton, Florida, USA, CRC Press).Google Scholar
- Komla-Soukha I and Sureau C (2006). A tryptophan-rich motif in the carboxyl-terminus of the small envelope protein of hepatitis B virus is central to the assembly of hepatitis delta virus particles. J Virol 80 (in press)Google Scholar
- Radjef N, Gordien E, Ivaniushina V, Gault E, Anais P, Drugan T, Trinchet JC, Roulot D, Tamby M, Milinkovitch MC, and Deny P (2004). Molecular phylogenetic analyses indicate a wide and ancient radiation of African hepatitis delta virus, suggesting a deltavirus genus of at least seven major clades. J Virol 78:2537–2544PubMedCrossRefGoogle Scholar
- Rizzetto M, Canese MG, Gerin JL, London WT, Sly DL, and Purcell RH (1980a).Google Scholar
- Transmission of the hepatitis B virus-associated delta antigen to chimpanzees. J Infect Dis 141:590–602Google Scholar
- Torresi J, Earnest-Silveira L, Deliyannis G, Edgtton K, Zhuang H, Locarnini SA, Fyfe J, Sozzi T, and Jackson DC (2002). Reduced antigenicity of the hepatitis B virus HBsAg protein arising as a consequence of sequence changes in the overlapping polymerase gene that are selected by lamivudine therapy. Virology 293:305–313PubMedCrossRefGoogle Scholar