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Published on: October 27, 2019
A unique virus release mechanism in the Archaea
Ariane Bize1, Erik A Karlsson, Karin Ekefjärd
1Biologie Moléculaire du Gène chez les Extrêmophiles, Institut Pasteur, 25 rue du Docteur Roux, 75724 Paris cedex 15, France.
Summary
Sulfolobus islandicus rod-shaped virus 2 (SIRV2) releases virions via unique pyramidal cell protrusions. This archaeal virus orchestrates host cell lysis and chromosome degradation for its lytic cycle.
Area of Science:
- Microbiology
- Virology
- Archaea Biology
Background:
- The infection cycles of viruses targeting Archaea, a distinct domain of life, remain largely uncharacterized.
- Understanding archaeal virus-host interactions is crucial for deciphering microbial ecosystem dynamics.
Purpose of the Study:
- To elucidate the infection and release mechanisms of Sulfolobus islandicus rod-shaped virus 2 (SIRV2) in its archaeal host.
- To investigate the impact of SIRV2 infection on host cell integrity and genetic material.
Main Methods:
- Observation of virus-induced cellular structures during virion release.
- Analysis of host chromosome degradation post-infection.
- Visualization of intracellular viral DNA using flow cytometry.
Main Results:
- SIRV2 virions are released through large, pyramidal protrusions that rupture the host cell envelope.
- Massive degradation of host chromosomes occurs during SIRV2 infection.
- Virion assembly takes place in the cytoplasm, and intracellular viral DNA is detectable.
Conclusions:
- SIRV2 functions as a lytic virus, employing sophisticated mechanisms to induce host cell death.
- The formation of virus-induced cellular structures for virion release is a novel finding in archaeal virus systems, previously only observed in eukaryotes.
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