title: Assembly and budding of a hepatitis B virus is mediated by a novel type of intracellular vesicles.
abstract: Formation of enveloped viruses involves assembly and budding at cellular membranes. In this study, we elucidated the morphogenesis of hepadnaviruses on the ultrastructural and biochemical level using duck hepatitis B virus (DHBV) as a model system. Formation of virus progeny initiates at the endoplasmic reticulum (ER) and is conserved both in vitro and in vivo. The morphogenesis proceeds via membrane-surrounded vesicles containing both virions and subviral particles, indicating a common morphogenetic pathway. The virus particle-containing vesicles (VCVs) are generated and maintained by reorganization of endomembranes accompanied by a striking disorganization of the rough ER (rER). VCVs are novel organelles with unique identity and properties of ER, intermediate compartment, endosomes, and multivesicular bodies. VCVs are dynamic structures whose size and shape are regulated by both membrane fusion and fission.
  
  
  CONCLUSIONS
  Our data indicate a strong reorganization of endomembranes during DHBV infection, resulting in the biogenesis of novel organelles serving as multifunctional platforms for assembly and budding of virus progeny.
authors.affiliation: Heinrich-Pette-Institut für experimentelle Virologie und Immunologie an der Universität Hamburg, Hamburg, Germany.
authors.forename: Mouna
authors.initials: M
authors.lastname: Mhamdi
authors.forename: Anneke
authors.initials: A
authors.lastname: Funk
authors.forename: Heinz
authors.initials: H
authors.lastname: Hohenberg
authors.forename: Hans
authors.initials: H
authors.lastname: Will
authors.forename: Hüseyin
authors.initials: H
authors.lastname: Sirma
mesh_terms: D000818:Animals; D002458:Cell Fractionation; D002462:Cell Membrane / Q000821:virology; D004372:Ducks; D004721:Endoplasmic Reticulum / Q000821:virology; D015611:Hepatitis B Virus, Duck / Q000235:genetics* / Q000254:growth & development / Q000302:isolation & purification; D006515:Hepatitis B virus / Q000254:growth & development / Q000302:isolation & purification / Q000502:physiology*; D022781:Hepatocytes / Q000648:ultrastructure / Q000821:virology*; D015388:Organelles / Q000821:virology; D010957:Plasmids; D014779:Virus Replication