1
|
Erazo-Garcia MP, Sheyn U, Barth ZK, Craig RJ, Wessman P, Jivaji AM, Ray WK, Svensson-Coelho M, Cornwallis CK, Rengefors K, Brussaard CPD, Moniruzzaman M, Aylward FO. Latent infection of an active giant endogenous virus in a unicellular green alga. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.09.03.611062. [PMID: 39282281 PMCID: PMC11398304 DOI: 10.1101/2024.09.03.611062] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 09/21/2024]
Abstract
Latency is a common strategy in a wide range of viral lineages, but its prevalence in giant viruses remains unknown. Here we describe the activity and viral production from a 617 kbp integrated giant viral element in the model green alga Chlamydomonas reinhardtii. We resolve the integrated viral region using long-read sequencing and show that viral particles are produced and released in otherwise healthy cultures. A diverse array of viral-encoded selfish genetic elements are expressed during GEVE reactivation and produce proteins that are packaged in virions. In addition, we show that field isolates of Chlamydomonas sp. harbor latent giant viruses related to the C. reinhardtii GEVE that exhibit similar infection dynamics, demonstrating that giant virus latency is prevalent in natural host communities. Our work reports the largest temperate virus documented to date and the first active GEVE identified in a unicellular eukaryote, substantially expanding the known limits of viral latency.
Collapse
Affiliation(s)
| | - Uri Sheyn
- Department of Biological Sciences, Virginia Tech; Blacksburg, 24061, USA
| | - Zachary K. Barth
- Department of Biological Sciences, Virginia Tech; Blacksburg, 24061, USA
| | - Rory J. Craig
- Department of Algal Development and Evolution, Max Planck Institute for Biology Tübingen; Tübingen, 72076, Germany
| | | | - Abdeali M. Jivaji
- Department of Biological Sciences, Virginia Tech; Blacksburg, 24061, USA
| | - W. Keith Ray
- Mass Spectrometry Incubator, Fralin Life Sciences Institute, Virginia Tech; Blacksburg, 24061, USA
| | - Maria Svensson-Coelho
- Department of Biology, Lund University; Lund, 223 62, Sweden
- Division of Molecular Biology, Department of Laboratory Medicine, Ryhov County Hospital; Jönköping, 55185, Sweden
| | | | - Karin Rengefors
- Department of Biology, Lund University; Lund, 223 62, Sweden
| | - Corina P. D. Brussaard
- Department of Biology, Lund University; Lund, 223 62, Sweden
- Department of Marine Microbiology and Biogeochemistry, Royal Netherlands Institute for Sea Research (NIOZ); Texel, 1790 AB, The Netherlands
- Institute for Biodiversity and Ecosystem Dynamics (IBED), University of Amsterdam; Amsterdam, 1090 GE, The Netherlands
| | - Mohammad Moniruzzaman
- Department of Marine Biology and Ecology, University of Miami; Coral Gables, 33149, USA
| | - Frank O. Aylward
- Department of Biological Sciences, Virginia Tech; Blacksburg, 24061, USA
- Center for Emerging, Zoonotic, and Arthropod-Borne Infectious Disease, Virginia Tech; Blacksburg, 24061, USA
| |
Collapse
|
2
|
Barth ZK, Hicklin I, Thézé J, Takatsuka J, Nakai M, Herniou EA, Brown AM, Aylward FO. Genomic analysis of hyperparasitic viruses associated with entomopoxviruses. Virus Evol 2024; 10:veae051. [PMID: 39100687 PMCID: PMC11296320 DOI: 10.1093/ve/veae051] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2023] [Revised: 05/17/2024] [Accepted: 07/11/2024] [Indexed: 08/06/2024] Open
Abstract
Polinton-like viruses (PLVs) are a diverse group of small integrative dsDNA viruses that infect diverse eukaryotic hosts. Many PLVs are hypothesized to parasitize viruses in the phylum Nucleocytoviricota for their own propagation and spread. Here, we analyze the genomes of novel PLVs associated with the occlusion bodies of entomopoxvirus (EPV) infections of two separate lepidopteran hosts. The presence of these elements within EPV occlusion bodies suggests that they are the first known hyperparasites of poxviruses. We find that these PLVs belong to two distinct lineages that are highly diverged from known PLVs. These PLVs possess mosaic genomes, and some essential genes share homology with mobile genes within EPVs. Based on this homology and observed PLV mosaicism, we propose a mechanism to explain the turnover of PLV replication and integration genes.
Collapse
Affiliation(s)
- Zachary K Barth
- Department of Biological Sciences, Virginia Tech, 926 West Campus Drive, Blacksburg, VA 24061, USA
| | - Ian Hicklin
- Department of Biochemistry, Virginia Tech, Blacksburg, VA 24061, USA
| | - Julien Thézé
- Université Clermont Auvergne, INRAE, VetAgro Sup, UMR EPIA, Saint-Genès-Champanelle, France
| | - Jun Takatsuka
- Forestry and Forest Products Research Institute, Matsunosato, Tsukuba, Ibaraki 305-8687, Japan
| | - Madoka Nakai
- Institute of Agriculture, Tokyo University of Agriculture and Technology, Saiwai, Fuchu, Tokyo 183-8509, Japan
| | - Elisabeth A Herniou
- Institut de Recherche sur la Biologie de l’Insecte, UMR7261 CNRS-Université de Tours, 20 Avenue Monge, Parc de Grandmont, Tours 37200, France
| | - Anne M Brown
- Department of Biochemistry, Virginia Tech, Blacksburg, VA 24061, USA
- Center for Emerging, Zoonotic, and Arthropod-Borne Pathogens, Virginia Tech, 1981 Kraft Dr, Blacksburg, VA 24061, USA
- Research and Informatics, University Libraries, Virginia Tech, Blacksburg, VA 24061, USA
| | - Frank O Aylward
- Department of Biological Sciences, Virginia Tech, 926 West Campus Drive, Blacksburg, VA 24061, USA
- Center for Emerging, Zoonotic, and Arthropod-Borne Pathogens, Virginia Tech, 1981 Kraft Dr, Blacksburg, VA 24061, USA
| |
Collapse
|
3
|
Zhao H, Meng L, Hikida H, Ogata H. Eukaryotic genomic data uncover an extensive host range of mirusviruses. Curr Biol 2024; 34:2633-2643.e3. [PMID: 38806056 DOI: 10.1016/j.cub.2024.04.085] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2024] [Revised: 04/10/2024] [Accepted: 04/30/2024] [Indexed: 05/30/2024]
Abstract
A recent marine metagenomic study has revealed the existence of a novel group of viruses designated mirusviruses, which are proposed to form an evolutionary link between two realms of double-stranded DNA viruses, Varidnaviria and Duplodnaviria. Metagenomic data suggest that mirusviruses infect microeukaryotes in the photic layer of the ocean, but their host range remains largely unknown. In this study, we investigated the presence of mirusvirus marker genes in 1,901 publicly available eukaryotic genome assemblies, mainly derived from unicellular eukaryotes, to identify potential hosts of mirusviruses. Mirusvirus marker sequences were identified in 915 assemblies spanning 227 genera across eight supergroups of eukaryotes. The habitats of the putative mirusvirus hosts included not only marine but also other diverse environments. Among the major capsid protein (MCP) signals in the genome assemblies, we identified 85 sequences that showed high sequence and structural similarities to reference mirusvirus MCPs. A phylogenetic analysis of these sequences revealed their distant evolutionary relationships with the seven previously reported mirusvirus clades. Most of the scaffolds with these MCP sequences encoded multiple mirusvirus homologs, suggesting that mirusviral infection contributes to the alteration of the host genome. We also identified three circular mirusviral genomes within the genomic data of the oil-producing thraustochytrid Schizochytrium sp. and the endolithic green alga Ostreobium quekettii. Overall, mirusviruses probably infect a wide spectrum of eukaryotes and are more diverse than previously reported.
Collapse
Affiliation(s)
- Hongda Zhao
- Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011, Japan
| | - Lingjie Meng
- Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011, Japan
| | - Hiroyuki Hikida
- Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011, Japan
| | - Hiroyuki Ogata
- Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011, Japan.
| |
Collapse
|
4
|
Zhao H, Meng L, Hikida H, Ogata H. Eukaryotic genomic data uncover an extensive host range of mirusviruses. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.01.18.576163. [PMID: 38293090 PMCID: PMC10827195 DOI: 10.1101/2024.01.18.576163] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2024]
Abstract
A recent marine metagenomic study has revealed the existence of a novel group of viruses designated mirusviruses, which are proposed to form an evolutionary link between two realms of double-stranded DNA viruses, Varidnaviria and Duplodnaviria. Metagenomic data suggest that mirusviruses infect microeukaryotes in the photic layer of the ocean, but their host range remains largely unknown. In this study, we investigated the presence of mirusvirus marker genes in publicly available 1,901 eukaryotic genome assemblies, mainly derived from unicellular eukaryotes, to identify potential hosts of mirusviruses. Mirusvirus marker sequences were identified in 1,348 assemblies spanning 284 genera across eight supergroups of eukaryotes. The habitats of the putative mirusvirus hosts included not only marine but also other diverse environments. Among the major capsid protein (MCP) signals in the genome assemblies, we identified 85 sequences that showed high sequence and structural similarities to reference mirusvirus MCPs. A phylogenetic analysis of these sequences revealed their distant evolutionary relationships with the seven previously reported mirusvirus clades. Most of the scaffolds with these MCP sequences encoded multiple mirusvirus homologs, underscoring the impact of mirusviral infection on the evolution of the host genome. We also identified three circular mirusviral genomes within the genomic data of the oil producing thraustochytrid Schizochytrium sp. and the endolithic green alga Ostreobium quekettii. Overall, mirusviruses probably infect a wide spectrum of eukaryotes and are more diverse than previously reported.
Collapse
Affiliation(s)
- Hongda Zhao
- Institute for Chemical Research, Kyoto University, Uji, Kyoto, Japan
| | - Lingjie Meng
- Institute for Chemical Research, Kyoto University, Uji, Kyoto, Japan
| | - Hiroyuki Hikida
- Institute for Chemical Research, Kyoto University, Uji, Kyoto, Japan
| | - Hiroyuki Ogata
- Institute for Chemical Research, Kyoto University, Uji, Kyoto, Japan
| |
Collapse
|
5
|
Koonin EV, Kuhn JH, Dolja VV, Krupovic M. Megataxonomy and global ecology of the virosphere. THE ISME JOURNAL 2024; 18:wrad042. [PMID: 38365236 PMCID: PMC10848233 DOI: 10.1093/ismejo/wrad042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2023] [Revised: 12/22/2023] [Accepted: 12/28/2023] [Indexed: 02/18/2024]
Abstract
Nearly all organisms are hosts to multiple viruses that collectively appear to be the most abundant biological entities in the biosphere. With recent advances in metagenomics and metatranscriptomics, the known diversity of viruses substantially expanded. Comparative analysis of these viruses using advanced computational methods culminated in the reconstruction of the evolution of major groups of viruses and enabled the construction of a virus megataxonomy, which has been formally adopted by the International Committee on Taxonomy of Viruses. This comprehensive taxonomy consists of six virus realms, which are aspired to be monophyletic and assembled based on the conservation of hallmark proteins involved in capsid structure formation or genome replication. The viruses in different major taxa substantially differ in host range and accordingly in ecological niches. In this review article, we outline the latest developments in virus megataxonomy and the recent discoveries that will likely lead to reassessment of some major taxa, in particular, split of three of the current six realms into two or more independent realms. We then discuss the correspondence between virus taxonomy and the distribution of viruses among hosts and ecological niches, as well as the abundance of viruses versus cells in different habitats. The distribution of viruses across environments appears to be primarily determined by the host ranges, i.e. the virome is shaped by the composition of the biome in a given habitat, which itself is affected by abiotic factors.
Collapse
Affiliation(s)
- Eugene V Koonin
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, MD 20894, United States
| | - Jens H Kuhn
- Integrated Research Facility at Fort Detrick, Division of Clinical Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Fort Detrick, Frederick, MD 21702, United States
| | - Valerian V Dolja
- Department of Botany and Plant Pathology, Oregon State University, Corvallis, OR 97331, United States
| | - Mart Krupovic
- Institut Pasteur, Université Paris Cité, Archaeal Virology Unit, 75015 Paris, France
| |
Collapse
|
6
|
Zhang L, Meng L, Fang Y, Ogata H, Okazaki Y. Spatiotemporal dynamics of giant viruses within a deep freshwater lake reveal a distinct dark-water community. THE ISME JOURNAL 2024; 18:wrae182. [PMID: 39312489 PMCID: PMC11465185 DOI: 10.1093/ismejo/wrae182] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2024] [Revised: 09/02/2024] [Accepted: 09/21/2024] [Indexed: 09/25/2024]
Abstract
Giant viruses (GVs) significantly regulate the ecological dynamics of diverse ecosystems. Although metagenomics has expanded our understanding of their diversity and ecological roles played in marine environments, little is known about GVs of freshwater ecosystems. Most previous studies have employed short-read sequencing and therefore resulted in fragmented genomes, hampering accurate assessment of genetic diversity. We sought to bridge this knowledge gap and overcome previous technical limitations. We subjected spatiotemporal (2 depths × 12 months) samples from Lake Biwa to metagenome-assembled genome reconstruction enhanced by long-read metagenomics. This yielded 293 GV metagenome-assembled genomes. Of these, 285 included previously unknown species in five orders of nucleocytoviruses and the first representatives of freshwater mirusviruses, which exhibited marked divergence from marine-derived lineages. The good performance of our long-read metagenomic assembly was demonstrated by the detection of 42 (14.3%) genomes composed of single contigs with completeness values >90%. GVs were partitioned across water depths, with most species specific to either the sunlit epilimnion or the dark hypolimnion. Epilimnion-specific members tended to be transient and exhibit short and intense abundance peaks, in line with the fact that they regulate the surface algal blooms. During the spring bloom, mirusviruses and members of three nucleocytovirus families were among the most abundant viruses. In contrast, hypolimnion-specific ones, including a mirusvirus genome, were typically more persistent in the hypolimnion throughout the water-stratified period, suggesting that they infect hosts specific to the hypolimnion and play previously unexplored ecological roles in dark water microbial ecosystems.
Collapse
Affiliation(s)
- Liwen Zhang
- Bioinformatics Center, Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011, Japan
| | - Lingjie Meng
- Bioinformatics Center, Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011, Japan
| | - Yue Fang
- Bioinformatics Center, Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011, Japan
| | - Hiroyuki Ogata
- Bioinformatics Center, Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011, Japan
| | - Yusuke Okazaki
- Bioinformatics Center, Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011, Japan
| |
Collapse
|
7
|
Abstract
Long-read sequencing of a marine stramenopile genome yields a trove of insights into protist genomics and solves a 50-year-old viral mystery.
Collapse
Affiliation(s)
- Frank O Aylward
- Department of Biological Sciences, Virginia Tech, Blacksburg, VA 24061, USA; Center for Emerging, Zoonotic, and Arthropod-Borne Pathogens, Blacksburg, VA 24061, USA.
| |
Collapse
|