A unique virus release mechanism in the Archaea.
Little is known about the infection cycles of viruses infecting cells from Archaea, the third domain of life. Here, we demonstrate that the virions of the archaeal Sulfolobus islandicus rod-shaped virus 2 (SIRV2) are released from the host cell through a mechanism, involving the formation of specific cellular structures. Large pyramidal virus-induced protrusions transect the cell envelope at several positions, rupturing the S-layer; they eventually open out, thus creating large apertures through which virions escape the cell. We also demonstrate that massive degradation of the host chromosomes occurs because of virus infection, and that virion assembly occurs in the cytoplasm. Furthermore, intracellular viral DNA is visualized by flow cytometry. The results show that SIRV2 is a lytic virus, and that the host cell dies as a consequence of elaborated mechanisms orchestrated by the virus. The generation of specific cellular structures for a distinct step of virus life cycle is known in eukaryal virus-host systems but is unprecedented in cells from other domains.
Bize
Ariane
A
Biologie Moléculaire du Gène chez les Extrêmophiles, Institut Pasteur, 25 rue du Docteur Roux, 75724 Paris cedex 15, France.
Karlsson
Erik A
EA
Ekefjärd
Karin
K
Quax
Tessa E F
TE
Pina
Mery
M
Prevost
Marie-Christine
MC
Forterre
Patrick
P
Tenaillon
Olivier
O
Bernander
Rolf
R
Prangishvili
David
D
D023641:Archaeal Viruses / Q000472:pathogenicity / Q000502:physiology*; D049109:Cell Proliferation; D002875:Chromosomes / Q000378:metabolism; D005434:Flow Cytometry; D007700:Kinetics; D016944:Sulfolobus / Q000166:cytology / Q000648:ultrastructure / Q000821:virology*; D013997:Time Factors