Composition and three-dimensional architecture of the dengue virus replication and assembly sites.
Positive-strand RNA viruses are known to rearrange cellular membranes to facilitate viral genome replication. The biogenesis and three-dimensional organization of these membranes and the link between replication and virus assembly sites is not fully clear. Using electron microscopy, we find Dengue virus (DENV)-induced vesicles, convoluted membranes, and virus particles to be endoplasmic reticulum (ER)-derived, and we detect double-stranded RNA, a presumed marker of RNA replication, inside virus-induced vesicles. Electron tomography (ET) shows DENV-induced membrane structures to be part of one ER-derived network. Furthermore, ET reveals vesicle pores that could enable release of newly synthesized viral RNA and reveals budding of DENV particles on ER membranes directly apposed to vesicle pores. Thus, DENV modifies ER membrane structure to promote replication and efficient encapsidation of the genome into progeny virus. This architecture of DENV replication and assembly sites could explain the coordination of distinct steps of the flavivirus replication cycle.
Welsch
Sonja
S
Department of Molecular Virology, University of Heidelberg, Im Neuenheimer Feld 345, Heidelberg D-69120, Germany.
Miller
Sven
S
Romero-Brey
Ines
I
Merz
Andreas
A
Bleck
Christopher K E
CK
Walther
Paul
P
Fuller
Stephen D
SD
Antony
Claude
C
Krijnse-Locker
Jacomine
J
Bartenschlager
Ralf
R
D045744:Cell Line, Tumor; D002462:Cell Membrane / Q000648:ultrastructure / Q000821:virology; D022162:Cytoplasmic Vesicles / Q000648:ultrastructure / Q000821:virology; D003716:Dengue Virus / Q000502:physiology* / Q000648:ultrastructure*; D004721:Endoplasmic Reticulum / Q000648:ultrastructure / Q000821:virology; D022781:Hepatocytes / Q000648:ultrastructure* / Q000821:virology*; D006801:Humans; D008854:Microscopy, Electron; D019065:Virus Assembly; D014779:Virus Replication