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Virophages and retrotransposons colonize the genomes of a heterotrophic flagellate
Virophages can parasitize giant DNA viruses and may provide adaptive anti-giant virus defense in unicellular eukaryotes. Under laboratory conditions, the virophage mavirus integrates into the nuclear genome of the marine flagellate Cafeteria burkhardae and reactivates upon superinfection with the gi...
Autores principales: | , , , , |
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Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
eLife Sciences Publications, Ltd
2021
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Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8547959/ https://www.ncbi.nlm.nih.gov/pubmed/34698016 http://dx.doi.org/10.7554/eLife.72674 |
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author | Hackl, Thomas Duponchel, Sarah Barenhoff, Karina Weinmann, Alexa Fischer, Matthias G |
author_facet | Hackl, Thomas Duponchel, Sarah Barenhoff, Karina Weinmann, Alexa Fischer, Matthias G |
author_sort | Hackl, Thomas |
collection | PubMed |
description | Virophages can parasitize giant DNA viruses and may provide adaptive anti-giant virus defense in unicellular eukaryotes. Under laboratory conditions, the virophage mavirus integrates into the nuclear genome of the marine flagellate Cafeteria burkhardae and reactivates upon superinfection with the giant virus CroV. In natural systems, however, the prevalence and diversity of host-virophage associations has not been systematically explored. Here, we report dozens of integrated virophages in four globally sampled C. burkhardae strains that constitute up to 2% of their host genomes. These endogenous mavirus-like elements (EMALEs) separated into eight types based on GC-content, nucleotide similarity, and coding potential and carried diverse promoter motifs implicating interactions with different giant viruses. Between host strains, some EMALE insertion loci were conserved indicating ancient integration events, whereas the majority of insertion sites were unique to a given host strain suggesting that EMALEs are active and mobile. Furthermore, we uncovered a unique association between EMALEs and a group of tyrosine recombinase retrotransposons, revealing yet another layer of parasitism in this nested microbial system. Our findings show that virophages are widespread and dynamic in wild Cafeteria populations, supporting their potential role in antiviral defense in protists. |
format | Online Article Text |
id | pubmed-8547959 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2021 |
publisher | eLife Sciences Publications, Ltd |
record_format | MEDLINE/PubMed |
spelling | pubmed-85479592021-10-27 Virophages and retrotransposons colonize the genomes of a heterotrophic flagellate Hackl, Thomas Duponchel, Sarah Barenhoff, Karina Weinmann, Alexa Fischer, Matthias G eLife Genetics and Genomics Virophages can parasitize giant DNA viruses and may provide adaptive anti-giant virus defense in unicellular eukaryotes. Under laboratory conditions, the virophage mavirus integrates into the nuclear genome of the marine flagellate Cafeteria burkhardae and reactivates upon superinfection with the giant virus CroV. In natural systems, however, the prevalence and diversity of host-virophage associations has not been systematically explored. Here, we report dozens of integrated virophages in four globally sampled C. burkhardae strains that constitute up to 2% of their host genomes. These endogenous mavirus-like elements (EMALEs) separated into eight types based on GC-content, nucleotide similarity, and coding potential and carried diverse promoter motifs implicating interactions with different giant viruses. Between host strains, some EMALE insertion loci were conserved indicating ancient integration events, whereas the majority of insertion sites were unique to a given host strain suggesting that EMALEs are active and mobile. Furthermore, we uncovered a unique association between EMALEs and a group of tyrosine recombinase retrotransposons, revealing yet another layer of parasitism in this nested microbial system. Our findings show that virophages are widespread and dynamic in wild Cafeteria populations, supporting their potential role in antiviral defense in protists. eLife Sciences Publications, Ltd 2021-10-26 /pmc/articles/PMC8547959/ /pubmed/34698016 http://dx.doi.org/10.7554/eLife.72674 Text en © 2021, Hackl et al https://creativecommons.org/licenses/by/4.0/This article is distributed under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0/) , which permits unrestricted use and redistribution provided that the original author and source are credited. |
spellingShingle | Genetics and Genomics Hackl, Thomas Duponchel, Sarah Barenhoff, Karina Weinmann, Alexa Fischer, Matthias G Virophages and retrotransposons colonize the genomes of a heterotrophic flagellate |
title | Virophages and retrotransposons colonize the genomes of a heterotrophic flagellate |
title_full | Virophages and retrotransposons colonize the genomes of a heterotrophic flagellate |
title_fullStr | Virophages and retrotransposons colonize the genomes of a heterotrophic flagellate |
title_full_unstemmed | Virophages and retrotransposons colonize the genomes of a heterotrophic flagellate |
title_short | Virophages and retrotransposons colonize the genomes of a heterotrophic flagellate |
title_sort | virophages and retrotransposons colonize the genomes of a heterotrophic flagellate |
topic | Genetics and Genomics |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8547959/ https://www.ncbi.nlm.nih.gov/pubmed/34698016 http://dx.doi.org/10.7554/eLife.72674 |
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