Host genome integration and giant virus-induced reactivation of the virophage mavirus

@article{Fischer2016HostGI,
  title={Host genome integration and giant virus-induced reactivation of the virophage mavirus},
  author={Matthias G. Fischer and Thomas Hackl},
  journal={Nature},
  year={2016},
  volume={540},
  pages={288-291}
}
Endogenous viral elements are increasingly found in eukaryotic genomes, yet little is known about their origins, dynamics, or function. Here we provide a compelling example of a DNA virus that readily integrates into a eukaryotic genome where it acts as an inducible antiviral defence system. We found that the virophage mavirus, a parasite of the giant Cafeteria roenbergensis virus (CroV), integrates at multiple sites within the nuclear genome of the marine protozoan Cafeteria roenbergensis. The… Expand
Virology: A parasite's parasite saves host's neighbours
TLDR
Mavirus, a virophage sharing an evolutionary origin with a class of self-synthesizing DNA transposons called Maverick/Polinton elements, integrates into the genome of the marine protozoan Cafeteria roenbergensis. Expand
Endogenous virophages populate the genomes of a marine heterotrophic flagellate
TLDR
The findings show that virophages are common, diverse, and dynamic genome components of the marine protist C. burkhardae, which implies important eco-evolutionary roles for these enigmatic viruses. Expand
A virophage cross-species infection through mutant selection represses giant virus propagation, promoting host cell survival
TLDR
Insight is provided into multi-level parasitic interactions among virophages, giant viruses, and protists as well as the relevant biological impact of this host adaptation by demonstrating that coinfection with a mixture containing mutants abolishes giant virus production and rescues the host cell population from lysis. Expand
Virophages and retrotransposons colonize the genomes of a heterotrophic flagellate
TLDR
It is shown that virophages are widespread and dynamic in wild Cafeteria populations, supporting their potential role in antiviral defense in protists and uncovered a unique association between EMALEs and a group of tyrosine recombinase retrotransposons, revealing yet another layer of parasitism in this nested microbial system. Expand
Virophages and retrotransposons colonize the genomes of a heterotrophic flagellate
TLDR
It is shown that virophages are widespread and dynamic in wild Cafeteria populations, supporting their potential role in antiviral defense in protists and uncovered a unique association between EMALEs and a group of tyrosine recombinase retrotransposons, revealing yet another layer of parasitism in this nested microbial system. Expand
Polintons, virophages and transpovirons: a tangled web linking viruses, transposons and immunity.
TLDR
Findings show that Polintons, PLV, virophages and transpovirons form a dynamic network of integrating mobile genetic elements that contribute to the cellular antivirus defense and host-virus coevolution. Expand
Giant Viruses and their mobile genetic elements: the molecular symbiotic hypothesis
TLDR
Protective effects provided by some of these MGEs may have generated an arms race between competing GVs in order to encode the most diverse arsenal of anti-viral weapons, explaining the unusual abundance of M GEs in GV genomes by a kind of ratchet effect. Expand
Giant Viruses and their mobile genetic elements: the molecular symbiotic hypothesis
TLDR
Protective effects provided by some of these MGEs may have generated an arms race between competing GVs in order to encode the most diverse arsenal of anti-viral weapons, explaining the unusual abundance of M GEs in GV genomes by a kind of ratchet effect. Expand
Viruses of Microorganisms
Double-stranded (ds) DNA viruses of the family Lavidaviridae, commonly known as virophages, are a fascinating group of eukaryotic viruses that depend on a coinfecting giant dsDNA virus of theExpand
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TLDR
It is proposed that MCP processing renders mavirus particles infection competent by loosening interactions between genome and capsid shell and destabilizing pentons for genome release into host cells, which provides a regulation mechanism for timing capsid maturation. Expand
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