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Fandiño S, Gomez-Lucia E, Benítez L, Doménech A. Comparison of Endogenous Alpharetroviruses (ALV-like) across Galliform Species: New Distant Proviruses. Microorganisms 2023; 12:86. [PMID: 38257913 PMCID: PMC10820513 DOI: 10.3390/microorganisms12010086] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2023] [Revised: 12/22/2023] [Accepted: 12/25/2023] [Indexed: 01/24/2024] Open
Abstract
The Genus Alpharetrovirus contains viruses pathogenic mainly for chickens, forming the Avian Sarcoma and Leukosis Virus group (ASLV). Cells of most Galliform species, besides chickens, contain genetic elements (endogenous retroviruses, ERVs) that could recombine with other alpharetroviruses or express proteins, complementing defective ASLV, which may successfully replicate and cause disease. However, they are quite unknown, and only ALV-F, from ring-necked pheasants, has been partially published. Upon scrutiny of 53 genomes of different avian species, we found Alpharetrovirus-like sequences only in 12 different Galliformes, including six full-length (7.4-7.6 Kbp) and 27 partial sequences. Phylogenetic studies of the regions studied (LTR, gag, pol, and env) consistently resulted in five almost identical clades containing the same ERVs: Clade I (presently known ASLVs); Clade II (Callipepla spp. ERVs); Clade IIIa (Phasianus colchicus ERVs); Clade IIIb (Alectoris spp. ERVs); and Clade IV (Centrocercus spp. ERVs). The low pol identity scores suggested that each of these Clades may be considered a different species. ORF analysis revealed that putatively encoded proteins would be very similar in length and domains to those of other alpharetroviruses and thus potentially functional. This will undoubtedly contribute to better understanding the biology of defective viruses, especially in wild Galliformes, their evolution, and the danger they may represent for other wild species and the poultry industry.
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Affiliation(s)
- Sergio Fandiño
- Department of Animal Health, Veterinary Faculty, Complutense University of Madrid, Av. Puerta de Hierro s/n, 28040 Madrid, Spain; (S.F.); (A.D.)
- Department of Genetics, Physiology and Microbiology, Faculty of Biological Sciences, Complutense University of Madrid (UCM), C. de José Antonio Novais 12, 28040 Madrid, Spain;
- Research Group, “Animal Viruses” of Complutense University of Madrid, 28040 Madrid, Spain
| | - Esperanza Gomez-Lucia
- Department of Animal Health, Veterinary Faculty, Complutense University of Madrid, Av. Puerta de Hierro s/n, 28040 Madrid, Spain; (S.F.); (A.D.)
- Research Group, “Animal Viruses” of Complutense University of Madrid, 28040 Madrid, Spain
| | - Laura Benítez
- Department of Genetics, Physiology and Microbiology, Faculty of Biological Sciences, Complutense University of Madrid (UCM), C. de José Antonio Novais 12, 28040 Madrid, Spain;
- Research Group, “Animal Viruses” of Complutense University of Madrid, 28040 Madrid, Spain
| | - Ana Doménech
- Department of Animal Health, Veterinary Faculty, Complutense University of Madrid, Av. Puerta de Hierro s/n, 28040 Madrid, Spain; (S.F.); (A.D.)
- Research Group, “Animal Viruses” of Complutense University of Madrid, 28040 Madrid, Spain
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Collier JL, Rest JS, Gallot-Lavallée L, Lavington E, Kuo A, Jenkins J, Plott C, Pangilinan J, Daum C, Grigoriev IV, Filloramo GV, Novák Vanclová AMG, Archibald JM. The protist Aurantiochytrium has universal subtelomeric rDNAs and is a host for mirusviruses. Curr Biol 2023; 33:5199-5207.e4. [PMID: 37913769 DOI: 10.1016/j.cub.2023.10.009] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2023] [Revised: 09/08/2023] [Accepted: 10/06/2023] [Indexed: 11/03/2023]
Abstract
Viruses are the most abundant biological entities in the world's oceans, where they play important ecological and biogeochemical roles. Metagenomics is revealing new groups of eukaryotic viruses, although disconnected from known hosts. Among these are the recently described mirusviruses, which share some similarities with herpesviruses.1 50 years ago, "herpes-type" viral particles2 were found in a thraustochytrid member of the labyrinthulomycetes, a diverse group of abundant and ecologically important marine eukaryotes,3,4 but could not be further characterized by methods then available. Long-read sequencing has allowed us to connect the biology of mirusviruses and thraustochytrids. We sequenced the genome of the genetically tractable model thraustochytrid Aurantiochytrium limacinum ATCC MYA-1381 and found that its 26 linear chromosomes have an extraordinary configuration. Subtelomeric ribosomal DNAs (rDNAs) found at all chromosome ends are interspersed with long repeated sequence elements denoted as long repeated-telomere and rDNA spacers (LORE-TEARS). We identified two genomic elements that are related to mirusvirus genomes. The first is a ∼300-kbp episome (circular element 1 [CE1]) present at a high copy number. Strikingly, the second, distinct, mirusvirus-like element is integrated between two sets of rDNAs and LORE-TEARS at the left end of chromosome 15 (LE-Chr15). Similar to metagenomically derived mirusviruses, these putative A. limacinum mirusviruses have a virion module related to that of herpesviruses along with an informational module related to nucleocytoplasmic large DNA viruses (NCLDVs). CE1 and LE-Chr15 bear striking similarities to episomal and endogenous latent forms of herpesviruses, respectively, and open new avenues of research into marine virus-host interactions.
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Affiliation(s)
- Jackie L Collier
- School of Marine and Atmospheric Sciences, Stony Brook University, Nicolls Road, Stony Brook, NY 11794, USA.
| | - Joshua S Rest
- Department of Ecology and Evolution, Stony Brook University, Nicolls Road, Stony Brook, NY 11794, USA.
| | - Lucie Gallot-Lavallée
- Department of Biochemistry & Molecular Biology, Dalhousie University, College Street, Halifax, NS B3H 4R2, Canada
| | - Erik Lavington
- Department of Ecology and Evolution, Stony Brook University, Nicolls Road, Stony Brook, NY 11794, USA
| | - Alan Kuo
- U.S. Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Cyclotron Road, Berkeley, CA 94720, USA
| | - Jerry Jenkins
- U.S. Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Cyclotron Road, Berkeley, CA 94720, USA; HudsonAlpha Institute for Biotechnology, Genome Way Northwest, Huntsville, AL 35806, USA
| | - Chris Plott
- U.S. Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Cyclotron Road, Berkeley, CA 94720, USA; HudsonAlpha Institute for Biotechnology, Genome Way Northwest, Huntsville, AL 35806, USA
| | - Jasmyn Pangilinan
- U.S. Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Cyclotron Road, Berkeley, CA 94720, USA
| | - Chris Daum
- U.S. Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Cyclotron Road, Berkeley, CA 94720, USA
| | - Igor V Grigoriev
- U.S. Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Cyclotron Road, Berkeley, CA 94720, USA; Department of Plant and Microbial Biology, University of California Berkeley, University Avenue, Berkeley, CA 94720, USA
| | - Gina V Filloramo
- Department of Biochemistry & Molecular Biology, Dalhousie University, College Street, Halifax, NS B3H 4R2, Canada
| | | | - John M Archibald
- Department of Biochemistry & Molecular Biology, Dalhousie University, College Street, Halifax, NS B3H 4R2, Canada
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Ahmed W, Smith WJM, Sirikanchana K, Kitajima M, Bivins A, Simpson SL. Influence of membrane pore-size on the recovery of endogenous viruses from wastewater using an Adsorption-Extraction method. J Virol Methods 2023; 317:114732. [PMID: 37080396 PMCID: PMC10111872 DOI: 10.1016/j.jviromet.2023.114732] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2023] [Revised: 03/22/2023] [Accepted: 04/14/2023] [Indexed: 04/22/2023]
Abstract
The ongoing COVID-19 pandemic has emphasized the significance of wastewater-based epidemiology (WBE) in monitoring and tracking the spread of infectious diseases, including SARS-CoV-2. The WBE approach relies on detecting genetic material from viruses in wastewater, which could provide an early warning of outbreaks in communities. In this study, we evaluated the recovery of four types of endogenous viruses, including non-enveloped DNA (crAssphage and human adenovirus 40/41), non-enveloped RNA (enterovirus), and enveloped RNA (SARS-CoV-2) viruses, from wastewater samples using the adsorption-extraction (AE) method with electronegative membranes of different pore sizes (0.22, 0.45, and 0.8 μm). Our findings showed that the membrane with a pore size of 0.80 μm performed similarly to the membrane with a pore size of 0.45 μm for virus capture (repeated measurement one-way ANOVA; p >0.05), indicating that larger pore size membranes could process larger sample volumes while maintaining similar virus capture efficiency. We determined the recovery efficiencies of indigenous crAssphage and pepper mild mottle virus, which showed recovery efficiencies ranging from 50% to 94% and from 20% to 62%, respectively. Our results suggest that the AE method is a cost-effective and efficient approach for virus recovery in wastewater, and the use of larger pore size membranes may be beneficial for processing larger sample volumes, particularly for environmental waters containing low concentrations of viruses. This study provides valuable information for optimizing the AE method for virus recovery from wastewater, which is essential for monitoring and tracking infectious diseases in communities.
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Affiliation(s)
- Warish Ahmed
- CSIRO Environment, Ecosciences Precinct, 41 Boggo Road, Dutton Park, QLD 4102, Australia.
| | - Wendy J M Smith
- CSIRO Environment, Ecosciences Precinct, 41 Boggo Road, Dutton Park, QLD 4102, Australia
| | - Kwanrawee Sirikanchana
- Research Laboratory of Biotechnology, Chulabhorn Research Institute, 54 Kampangpetch 6 Road, Laksi, Bangkok 10210, Thailand
| | - Masaaki Kitajima
- Division of Environmental Engineering, Faculty of Engineering, Hokkaido University, North 13 West 8, Kita-ku, Sapporo, Hokkaido 060 -8628, Japan
| | - Aaron Bivins
- Department of Civil and Environmental Engineering, Louisiana State University, 3255 Patrick F. Taylor Hall, Baton Rouge, LA 70803, USA
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Kovarik A, Hemleben V. A commentary on: 'Broken, silent and in hiding: tamed endogenous pararetroviruses escape elimination from the genome of sugar beet (Beta vulgaris)'. Ann Bot 2021; 128:iii-iv. [PMID: 34350938 PMCID: PMC8389174 DOI: 10.1093/aob/mcab068] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
This article comments on: Nicola Schmidt, Kathrin M. Seibt, Beatrice Weber, Trude Schwarzacher, Thomas Schmidt, and Tony Heitkam, Broken, silent, and in hiding: tamed endogenous pararetroviruses escape elimination from the genome of sugar beet (Beta vulgaris), Annals of Botany Volume 128, Issue 3, 26 August 2021, Pages 281–291, https://doi.org/10.1093/aob/mcab042
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Affiliation(s)
- Ales Kovarik
- Laboratory of Molecular Epigenetics, Intitute of Biophysics, Academy of Sciences of the Czech Republic, v.v.i., Královopolská 135, Brno, Czech Republic
| | - Vera Hemleben
- Center of Plant Molecular Biology (ZMBP), University of Tübingen, Auf der Morgenstelle, Tübingen, Germany
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Shmookler Reis RJ, Atluri R, Balasubramaniam M, Johnson J, Ganne A, Ayyadevara S. "Protein aggregates" contain RNA and DNA, entrapped by misfolded proteins but largely rescued by slowing translational elongation. Aging Cell 2021; 20:e13326. [PMID: 33788386 PMCID: PMC8135009 DOI: 10.1111/acel.13326] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2020] [Revised: 01/12/2021] [Accepted: 02/01/2021] [Indexed: 01/03/2023] Open
Abstract
All neurodegenerative diseases feature aggregates, which usually contain disease-specific diagnostic proteins; non-protein constituents, however, have rarely been explored. Aggregates from SY5Y-APPSw neuroblastoma, a cell model of familial Alzheimer's disease, were crosslinked and sequences of linked peptides identified. We constructed a normalized "contactome" comprising 11 subnetworks, centered on 24 high-connectivity hubs. Remarkably, all 24 are nucleic acid-binding proteins. This led us to isolate and sequence RNA and DNA from Alzheimer's and control aggregates. RNA fragments were mapped to the human genome by RNA-seq and DNA by ChIP-seq. Nearly all aggregate RNA sequences mapped to specific genes, whereas DNA fragments were predominantly intergenic. These nucleic acid mappings are all significantly nonrandom, making an artifactual origin extremely unlikely. RNA (mostly cytoplasmic) exceeded DNA (chiefly nuclear) by twofold to fivefold. RNA fragments recovered from AD tissue were ~1.5-to 2.5-fold more abundant than those recovered from control tissue, similar to the increase in protein. Aggregate abundances of specific RNA sequences were strikingly differential between cultured SY5Y-APPSw glioblastoma cells expressing APOE3 vs. APOE4, consistent with APOE4 competition for E-box/CLEAR motifs. We identified many G-quadruplex and viral sequences within RNA and DNA of aggregates, suggesting that sequestration of viral genomes may have driven the evolution of disordered nucleic acid-binding proteins. After RNA-interference knockdown of the translational-procession factor EEF2 to suppress translation in SY5Y-APPSw cells, the RNA content of aggregates declined by >90%, while reducing protein content by only 30% and altering DNA content by ≤10%. This implies that cotranslational misfolding of nascent proteins may ensnare polysomes into aggregates, accounting for most of their RNA content.
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Affiliation(s)
- Robert J. Shmookler Reis
- Central Arkansas Veterans Healthcare System Little Rock AR USA
- Department of Geriatrics University of Arkansas for Medical Sciences Little Rock AR USA
- BioInformatics Program University of Arkansas for Medical Sciences and University of Arkansas at Little Rock Little Rock AR USA
| | - Ramani Atluri
- Department of Geriatrics University of Arkansas for Medical Sciences Little Rock AR USA
| | | | - Jay Johnson
- BioInformatics Program University of Arkansas for Medical Sciences and University of Arkansas at Little Rock Little Rock AR USA
| | - Akshatha Ganne
- BioInformatics Program University of Arkansas for Medical Sciences and University of Arkansas at Little Rock Little Rock AR USA
| | - Srinivas Ayyadevara
- Central Arkansas Veterans Healthcare System Little Rock AR USA
- Department of Geriatrics University of Arkansas for Medical Sciences Little Rock AR USA
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Volkoff AN, Cusson M. The Unconventional Viruses of Ichneumonid Parasitoid Wasps. Viruses 2020; 12:E1170. [PMID: 33076395 DOI: 10.3390/v12101170] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2020] [Revised: 10/07/2020] [Accepted: 10/08/2020] [Indexed: 12/18/2022] Open
Abstract
To ensure their own immature development as parasites, ichneumonid parasitoid wasps use endogenous viruses that they acquired through ancient events of viral genome integration. Thousands of species from the campoplegine and banchine wasp subfamilies rely, for their survival, on their association with these viruses, hijacked from a yet undetermined viral taxon. Here, we give an update of recent findings on the nature of the viral genes retained from the progenitor viruses and how they are organized in the wasp genome.
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Drezen JM, Josse T, Bézier A, Gauthier J, Huguet E, Herniou EA. Impact of Lateral Transfers on the Genomes of Lepidoptera. Genes (Basel) 2017; 8:E315. [PMID: 29120392 PMCID: PMC5704228 DOI: 10.3390/genes8110315] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2017] [Revised: 10/31/2017] [Accepted: 11/01/2017] [Indexed: 11/25/2022] Open
Abstract
Transfer of DNA sequences between species regardless of their evolutionary distance is very common in bacteria, but evidence that horizontal gene transfer (HGT) also occurs in multicellular organisms has been accumulating in the past few years. The actual extent of this phenomenon is underestimated due to frequent sequence filtering of "alien" DNA before genome assembly. However, recent studies based on genome sequencing have revealed, and experimentally verified, the presence of foreign DNA sequences in the genetic material of several species of Lepidoptera. Large DNA viruses, such as baculoviruses and the symbiotic viruses of parasitic wasps (bracoviruses), have the potential to mediate these transfers in Lepidoptera. In particular, using ultra-deep sequencing, newly integrated transposons have been identified within baculovirus genomes. Bacterial genes have also been acquired by genomes of Lepidoptera, as in other insects and nematodes. In addition, insertions of bracovirus sequences were present in the genomes of certain moth and butterfly lineages, that were likely corresponding to rearrangements of ancient integrations. The viral genes present in these sequences, sometimes of hymenopteran origin, have been co-opted by lepidopteran species to confer some protection against pathogens.
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Affiliation(s)
- Jean-Michel Drezen
- Institut de Recherche sur la Biologie de l'Insecte, UMR CNRS 7261, UFR des Sciences et Techniques, Université de Tours-François Rabelais, 37200 Tours, France.
| | - Thibaut Josse
- Institut de Recherche sur la Biologie de l'Insecte, UMR CNRS 7261, UFR des Sciences et Techniques, Université de Tours-François Rabelais, 37200 Tours, France.
| | - Annie Bézier
- Institut de Recherche sur la Biologie de l'Insecte, UMR CNRS 7261, UFR des Sciences et Techniques, Université de Tours-François Rabelais, 37200 Tours, France.
| | - Jérémy Gauthier
- Institut de Recherche sur la Biologie de l'Insecte, UMR CNRS 7261, UFR des Sciences et Techniques, Université de Tours-François Rabelais, 37200 Tours, France.
| | - Elisabeth Huguet
- Institut de Recherche sur la Biologie de l'Insecte, UMR CNRS 7261, UFR des Sciences et Techniques, Université de Tours-François Rabelais, 37200 Tours, France.
| | - Elisabeth Anne Herniou
- Institut de Recherche sur la Biologie de l'Insecte, UMR CNRS 7261, UFR des Sciences et Techniques, Université de Tours-François Rabelais, 37200 Tours, France.
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Abstract
Psychologists and psychiatrists tend to be little aware that (a) microbes in our brains and guts are capable of altering our behavior; (b) viral DNA that was incorporated into our DNA millions of years ago is implicated in mental disorders; (c) many of us carry the cells of another human in our brains; and (d) under the regulation of viruslike elements, the paternally inherited and maternally inherited copies of some genes compete for domination in the offspring, on whom they have opposite physical and behavioral effects. This article provides a broad overview, aimed at a wide readership, of the consequences of our coexistence with these selfish entities. The overarching message is that we are not unitary individuals but superorganisms, built out of both human and nonhuman elements; it is their interaction that determines who we are.
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Affiliation(s)
- Peter Kramer
- Department of General Psychology, University of Padua, Italy
| | - Paola Bressan
- Department of General Psychology, University of Padua, Italy
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Abstract
Endogenous viruses are viral genomes that became integrated into the germline genome of their hosts and vertically inherited, from generation to generation, in host populations. Recent advances in genome sequencing have triggered the discovery of many non-retroviral endogenous viruses, showing that all types of eukaryotic viruses can become endogenous. This article first explains some of the methods that are used to systematically detect endogenous viruses in eukaryotic genomes and provides a detailed account of the various ways through which these viruses can shape the evolution of their host's genomes. It then shows how the discovery of endogenous viruses can shed new light on our knowledge of the origin and evolution of current viruses, as well as on the ecology of virus-host interactions. Finally, several research directions are proposed, and it is argued that an approach coupling paleovirology and virology can reveal the full complexity of the interactions between endogenous viruses, current viruses and their hosts.
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Abstract
Ubiquitous, reverse transcriptase may have contributed to the transition from the RNA to the DNA world, a transition that also involved RNase H-like activities. Both enzymes shaped various genomes and antiviral defense systems as endogenous retroviruses (ERVs) and transposable elements (TEs). A close relationship between a dozen components of retroviruses and the small interfering RNA (siRNA) antiviral-defense machinery has been characterized. Most antiviral-defense systems involve RNase H-like enzymes destroying invading nucleic acids, RNA, or DNA. Such enzymes include RNases H, Argonaute, Dicer, Cas9, transposases, integrases, and enzymes for immunoglobulin rearrangement and splicing. Even in mammalian cells, where protein-based defense dominates, the siRNA machinery remains active, demonstrated by increased virus production and apoptosis after Dicer knockdown. We have noticed a surprising homology between the siRNA silencing system and the interferon response, as well as to siDNA and the CRISPR system. Further, ERVs serve in defense, in addition to having roles in gene regulation and cancer.
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Affiliation(s)
- Karin Moelling
- Max Planck Institute for Molecular Genetics, Berlin, Germany; Institute of Medical Microbiology, University of Zurich, Zurich, Switzerland; Heinrich Pette Institute, Hamburg, Germany
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Jalasvuori M, Lehtonen J. Virus epidemics can lead to a population-wide spread of intragenomic parasites in a previously parasite-free asexual population. Mol Ecol 2014; 23:987-91. [PMID: 24400851 DOI: 10.1111/mec.12662] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2012] [Revised: 11/15/2013] [Accepted: 12/27/2013] [Indexed: 12/29/2022]
Abstract
Sexual reproduction is problematic to explain due to its costs, most notably the twofold cost of sex. Yet, sex has been suggested to be favourable in the presence of proliferating intragenomic parasites given that sexual recombination provides a mechanism to confine the accumulation of deleterious mutations. Kraaijeveld et al. compared recently the accumulation of transposons in sexually and asexually reproducing lines of the same species, the parasitoid wasp Leptopilina clavipes. They discovered that within asexually reproducing wasps, the number of gypsy-like retrotransposons was increased fourfold, whereas other retrotransposons were not. Interestingly, gypsy-like retrotransposons are closely related to retroviruses. Endogenous retroviruses are retroviruses that have integrated to the germ line cells and are inherited thereafter vertically. They can also replicate within the genome similarly to retrotransposons as well as form virus particles and infect previously uninfected cells. This highlights the possibility that endogenous retroviruses could play a role in the evolution of sexual reproduction. Here, we show with an individual-based computational model that a virus epidemic within a previously parasite-free asexual population may establish a new intragenomic parasite to the population. Moreover and in contrast to other transposons, the possibility of endogenous viruses to maintain a virus epidemic and simultaneously provide resistance to individuals carrying active endogenous viruses selects for the presence of active intragenomic parasites in the population despite their deleterious effects. Our results suggest that the viral nature of certain intragenomic parasites should be taken into account when sex and its benefits are being considered.
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Affiliation(s)
- Matti Jalasvuori
- Division of Evolution Ecology and Genetics, Centre of Excellence in Biological Interactions, Research School of Biology, The Australian National University, Canberra, ACT, 0200, Australia; Department of Biological and Environmental Science, Centre of Excellence in Biological Interactions, University of Jyväskylä, PO Box 35, Jyväskylä, 40014, Finland
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Abstract
Two strains of feline leukemia virus, two endogenous feline type-C viruses (RD/CCC group), several endogenous and laboratory strains of murine "leukemia" virus, two rat viruses, two primate viruses (woolly monkey and gibbon ape), as well as hamster, pig, and avian type-C viruses were examined for their relatedness to one another by molecular hybridization. The extent of nucleic-acid homology was determined by hybridization of the various viral RNAs to a [(3)H]DNA product synthesized from each virus. Among the murine type-C viruses (Rauscher, Kirsten, AT-124, and endogenous BALB/c virus) a high degree of homology is observed, although the viruses are not identical. The two primate viruses are also closely related to one another. The feline, rat, hamster, and pig endogenous viruses can be readily distinguished from one another and from the murine and primate viruses since their DNA products share very little or no nucleic-acid homology. However, the murine and primate type-C virus groups possess a surprising degree of relatedness. Feline type-C viruses fall into two distinct groups, the feline leukemia virus group and the RD-114/CCC group, with little detectable nucleic-acid homology between them. Infection of feline or rat cells with type-C virus results in production of the endogenous type-C virus of the species along with the infecting virus.
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