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Yutin N, Mutz P, Krupovic M, Koonin EV. Mriyaviruses: small relatives of giant viruses. mBio 2024:e0103524. [PMID: 38832788 DOI: 10.1128/mbio.01035-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2024] [Accepted: 05/01/2024] [Indexed: 06/05/2024] Open
Abstract
The phylum Nucleocytoviricota consists of large and giant viruses that range in genome size from about 100 kilobases (kb) to more than 2.5 megabases. Here, using metagenome mining followed by extensive phylogenomic analysis and protein structure comparison, we delineate a distinct group of viruses with double-stranded (ds) DNA genomes in the range of 35-45 kb that appear to be related to the Nucleocytoviricota. In phylogenetic trees of the conserved double jelly-roll major capsid proteins (MCPs) and DNA packaging ATPases, these viruses do not show affinity to any particular branch of the Nucleocytoviricota and accordingly would comprise a class which we propose to name "Mriyaviricetes" (after Ukrainian "mriya," dream). Structural comparison of the MCP suggests that, among the extant virus lineages, mriyaviruses are the closest one to the ancestor of the Nucleocytoviricota. In the phylogenetic trees, mriyaviruses split into two well-separated branches, the family Yaraviridae and proposed new family "Gamadviridae." The previously characterized members of these families, yaravirus and Pleurochrysis sp. endemic viruses, infect amoeba and haptophytes, respectively. The genomes of the rest of the mriyaviruses were assembled from metagenomes from diverse environments, suggesting that mriyaviruses infect various unicellular eukaryotes. Mriyaviruses lack DNA polymerase, which is encoded by all other members of the Nucleocytoviricota, and RNA polymerase subunits encoded by all cytoplasmic viruses among the Nucleocytoviricota, suggesting that they replicate in the host cell nuclei. All mriyaviruses encode a HUH superfamily endonuclease that is likely to be essential for the initiation of virus DNA replication via the rolling circle mechanism. IMPORTANCE The origin of giant viruses of eukaryotes that belong to the phylum Nucleocytoviricota is not thoroughly understood and remains a matter of major interest and debate. Here, we combine metagenome database searches with extensive protein sequence and structure analysis to describe a distinct group of viruses with comparatively small genomes of 35-45 kilobases that appear to comprise a distinct class within the phylum Nucleocytoviricota that we provisionally named "Mriyaviricetes." Mriyaviruses appear to be the closest identified relatives of the ancestors of the Nucleocytoviricota. Analysis of proteins encoded in mriyavirus genomes suggests that they replicate their genome via the rolling circle mechanism that is unusual among viruses with double-stranded DNA genomes and so far not described for members of Nucleocytoviricota.
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Affiliation(s)
- Natalya Yutin
- National Center for Biotechnology Information, National Library of Medicine, Bethesda, Maryland, USA
| | - Pascal Mutz
- National Center for Biotechnology Information, National Library of Medicine, Bethesda, Maryland, USA
| | - Mart Krupovic
- Institut Pasteur, Université Paris Cité, Archaeal Virology Unit, Paris, France
| | - Eugene V Koonin
- National Center for Biotechnology Information, National Library of Medicine, Bethesda, Maryland, USA
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2
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Krupovic M, Kuhn JH, Fischer MG, Koonin EV. Natural history of eukaryotic DNA viruses with double jelly-roll major capsid proteins. Proc Natl Acad Sci U S A 2024; 121:e2405771121. [PMID: 38805295 PMCID: PMC11161782 DOI: 10.1073/pnas.2405771121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2024] [Accepted: 04/29/2024] [Indexed: 05/30/2024] Open
Abstract
The phylum Preplasmiviricota (kingdom Bamfordvirae, realm Varidnaviria) is a broad assemblage of diverse viruses with comparatively short double-stranded DNA genomes (<50 kbp) that produce icosahedral capsids built from double jelly-roll major capsid proteins. Preplasmiviricots infect hosts from all cellular domains, testifying to their ancient origin, and, in particular, are associated with six of the seven supergroups of eukaryotes. Preplasmiviricots comprise four major groups of viruses, namely, polintons, polinton-like viruses (PLVs), virophages, and adenovirids. We used protein structure modeling and analysis to show that protein-primed DNA polymerases (pPolBs) of polintons, virophages, and cytoplasmic linear plasmids encompass an N-terminal domain homologous to the terminal proteins (TPs) of prokaryotic PRD1-like tectivirids and eukaryotic adenovirids that are involved in protein-primed replication initiation, followed by a viral ovarian tumor-like cysteine deubiquitinylase (vOTU) domain. The vOTU domain is likely responsible for the cleavage of the TP from the large pPolB polypeptide and is inactivated in adenovirids, in which TP is a separate protein. Many PLVs and transpovirons encode a distinct derivative of polinton-like pPolB that retains the TP, vOTU, and pPolB polymerization palm domains but lacks the exonuclease domain and instead contains a superfamily 1 helicase domain. Analysis of the presence/absence and inactivation of the vOTU domains and replacement of pPolB with other DNA polymerases in eukaryotic preplasmiviricots enabled us to outline a complete scenario for their origin and evolution.
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Affiliation(s)
- Mart Krupovic
- Archaeal Virology Unit, Institut Pasteur, Université Paris Cité, Paris75015, France
| | - Jens H. Kuhn
- Integrated Research Facility at Fort Detrick, National Institute of Allergy and Infectious Diseases, NIH, Fort Detrick, Frederick, MD21702
| | - Matthias G. Fischer
- Department of Biomolecular Mechanisms, Max Planck Institute for Medical Research, Heidelberg69120, Germany
| | - Eugene V. Koonin
- National Center for Biotechnology Information, National Library of Medicine, NIH, Bethesda, MD20894
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3
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Blanco-Melo D, Campbell MA, Zhu H, Dennis TPW, Modha S, Lytras S, Hughes J, Gatseva A, Gifford RJ. A novel approach to exploring the dark genome and its application to mapping of the vertebrate virus fossil record. Genome Biol 2024; 25:120. [PMID: 38741126 PMCID: PMC11089739 DOI: 10.1186/s13059-024-03258-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2023] [Accepted: 04/22/2024] [Indexed: 05/16/2024] Open
Abstract
BACKGROUND Genomic regions that remain poorly understood, often referred to as the dark genome, contain a variety of functionally relevant and biologically informative features. These include endogenous viral elements (EVEs)-virus-derived sequences that can dramatically impact host biology and serve as a virus fossil record. In this study, we introduce a database-integrated genome screening (DIGS) approach to investigate the dark genome in silico, focusing on EVEs found within vertebrate genomes. RESULTS Using DIGS on 874 vertebrate genomes, we uncover approximately 1.1 million EVE sequences, with over 99% originating from endogenous retroviruses or transposable elements that contain EVE DNA. We show that the remaining 6038 sequences represent over a thousand distinct horizontal gene transfer events across 10 virus families, including some that have not previously been reported as EVEs. We explore the genomic and phylogenetic characteristics of non-retroviral EVEs and determine their rates of acquisition during vertebrate evolution. Our study uncovers novel virus diversity, broadens knowledge of virus distribution among vertebrate hosts, and provides new insights into the ecology and evolution of vertebrate viruses. CONCLUSIONS We comprehensively catalog and analyze EVEs within 874 vertebrate genomes, shedding light on the distribution, diversity, and long-term evolution of viruses and reveal their extensive impact on vertebrate genome evolution. Our results demonstrate the power of linking a relational database management system to a similarity search-based screening pipeline for in silico exploration of the dark genome.
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Affiliation(s)
- Daniel Blanco-Melo
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Center, 1100 Fairview Ave N, Seattle, WA, 98109, USA
- Herbold Computational Biology Program, Public Health Sciences Division, Fred Hutchinson Cancer Center, 1100 Fairview Ave N, Seattle, WA, 98109, USA
| | | | - Henan Zhu
- MRC-University of Glasgow Centre for Virus Research, 464 Bearsden Rd, Bearsden, Glasgow, G61 1QH, UK
| | - Tristan P W Dennis
- MRC-University of Glasgow Centre for Virus Research, 464 Bearsden Rd, Bearsden, Glasgow, G61 1QH, UK
| | - Sejal Modha
- MRC-University of Glasgow Centre for Virus Research, 464 Bearsden Rd, Bearsden, Glasgow, G61 1QH, UK
| | - Spyros Lytras
- MRC-University of Glasgow Centre for Virus Research, 464 Bearsden Rd, Bearsden, Glasgow, G61 1QH, UK
| | - Joseph Hughes
- MRC-University of Glasgow Centre for Virus Research, 464 Bearsden Rd, Bearsden, Glasgow, G61 1QH, UK
| | - Anna Gatseva
- MRC-University of Glasgow Centre for Virus Research, 464 Bearsden Rd, Bearsden, Glasgow, G61 1QH, UK
| | - Robert J Gifford
- MRC-University of Glasgow Centre for Virus Research, 464 Bearsden Rd, Bearsden, Glasgow, G61 1QH, UK.
- Centre for Epidemic Response and Innovation (CERI), School of Data Science and Computational Thinking, Stellenbosch University, Stellenbosch, South Africa.
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Marinov GK, Chen X, Swaffer MP, Xiang T, Grossman AR, Greenleaf WJ. Genome-wide distribution of 5-hydroxymethyluracil and chromatin accessibility in the Breviolum minutum genome. Genome Biol 2024; 25:115. [PMID: 38711126 PMCID: PMC11071213 DOI: 10.1186/s13059-024-03261-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2023] [Accepted: 04/28/2024] [Indexed: 05/08/2024] Open
Abstract
BACKGROUND In dinoflagellates, a unique and extremely divergent genomic and nuclear organization has evolved. The highly unusual features of dinoflagellate nuclei and genomes include permanently condensed liquid crystalline chromosomes, primarily packaged by proteins other than histones, genes organized in very long unidirectional gene arrays, a general absence of transcriptional regulation, high abundance of the otherwise very rare DNA modification 5-hydroxymethyluracil (5-hmU), and many others. While most of these fascinating properties are originally identified in the 1970s and 1980s, they have not yet been investigated using modern genomic tools. RESULTS In this work, we address some of the outstanding questions regarding dinoflagellate genome organization by mapping the genome-wide distribution of 5-hmU (using both immunoprecipitation-based and basepair-resolution chemical mapping approaches) and of chromatin accessibility in the genome of the Symbiodiniaceae dinoflagellate Breviolum minutum. We find that the 5-hmU modification is preferentially enriched over certain classes of repetitive elements, often coincides with the boundaries between gene arrays, and is generally correlated with decreased chromatin accessibility, the latter otherwise being largely uniform along the genome. We discuss the potential roles of 5-hmU in the functional organization of dinoflagellate genomes and its relationship to the transcriptional landscape of gene arrays. CONCLUSIONS Our results provide the first window into the 5-hmU and chromatin accessibility landscapes in dinoflagellates.
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Affiliation(s)
- Georgi K Marinov
- Department of Genetics, Stanford University, Stanford, CA, 94305, USA.
| | - Xinyi Chen
- Department of Bioengineering, Stanford University, Stanford, CA, 94305, USA
| | - Matthew P Swaffer
- Department of Biology, Stanford University, Stanford, CA, 94305, USA
| | - Tingting Xiang
- Department of Plant Biology, Carnegie Institution for Science, Stanford, CA, 94305, USA
| | - Arthur R Grossman
- Department of Plant Biology, Carnegie Institution for Science, Stanford, CA, 94305, USA
| | - William J Greenleaf
- Department of Genetics, Stanford University, Stanford, CA, 94305, USA.
- Center for Personal Dynamic Regulomes, Stanford University, Stanford, CA, 94305, USA.
- Department of Applied Physics, Stanford University, Stanford, CA, 94305, USA.
- Chan Zuckerberg Biohub, San Francisco, CA, USA.
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Yutin N, Tolstoy I, Mutz P, Wolf YI, Krupovic M, Koonin EV. Jumping DNA polymerases in bacteriophages. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.04.26.591309. [PMID: 38903090 PMCID: PMC11188092 DOI: 10.1101/2024.04.26.591309] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/22/2024]
Abstract
Viruses with double-stranded (ds) DNA genomes in the realm Duplodnaviria share a conserved structural gene module but show a broad range of variation in their repertoires of DNA replication proteins. Some of the duplodnaviruses encode (nearly) complete replication systems whereas others lack (almost) all genes required for replication, relying on the host replication machinery. DNA polymerases (DNAPs) comprise the centerpiece of the DNA replication apparatus. The replicative DNAPs are classified into 4 unrelated or distantly related families (A-D), with the protein structures and sequences within each family being, generally, highly conserved. More than half of the duplodnaviruses encode a DNAP of family A, B or C. We showed previously that multiple pairs of closely related viruses in the order Crassvirales encode DNAPs of different families. Here we identify four additional groups of tailed phages in the class Caudoviricetes in which the DNAPs apparently were swapped on multiple occasions, with replacements occurring both between families A and B, or A and C, or between distinct subfamilies within the same family. The DNAP swapping always occurs "in situ", without changes in the organization of the surrounding genes. In several cases, the DNAP gene is the only region of substantial divergence between closely related phage genomes, whereas in others, the swap apparently involved neighboring genes encoding other proteins involved in phage replication. We hypothesize that DNAP swapping is driven by selection for avoidance of host antiphage mechanisms targeting the phage DNAP that remain to be identified, and/or by selection against replicon incompatibility. In addition, we identified two previously undetected, highly divergent groups of family A DNAPs that are encoded in some phage genomes along with the main DNAP implicated in genome replication.
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Affiliation(s)
- Natalya Yutin
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, Maryland, USA
| | - Igor Tolstoy
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, Maryland, USA
| | - Pascal Mutz
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, Maryland, USA
| | - Yuri I Wolf
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, Maryland, USA
| | - Mart Krupovic
- Institut Pasteur, Université Paris Cité, Archaeal Virology Unit, Paris, France
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Zhang T, Peng W, Xiao H, Cao S, Chen Z, Su X, Luo Y, Liu Z, Peng Y, Yang X, Jiang GF, Xu X, Ma Z, Zhou Y. Population genomics highlights structural variations in local adaptation to saline coastal environments in woolly grape. JOURNAL OF INTEGRATIVE PLANT BIOLOGY 2024. [PMID: 38578160 DOI: 10.1111/jipb.13653] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/27/2023] [Accepted: 03/04/2024] [Indexed: 04/06/2024]
Abstract
Structural variations (SVs) are a feature of plant genomes that has been largely unexplored despite their significant impact on plant phenotypic traits and local adaptation to abiotic and biotic stress. In this study, we employed woolly grape (Vitis retordii), a species native to the tropical and subtropical regions of East Asia with both coastal and inland habitats, as a valuable model for examining the impact of SVs on local adaptation. We assembled a haplotype-resolved chromosomal reference genome for woolly grape, and conducted population genetic analyses based on whole-genome sequencing (WGS) data from coastal and inland populations. The demographic analyses revealed recent bottlenecks in all populations and asymmetric gene flow from the inland to the coastal population. In total, 1,035 genes associated with plant adaptive regulation for salt stress, radiation, and environmental adaptation were detected underlying local selection by SVs and SNPs in the coastal population, of which 37.29% and 65.26% were detected by SVs and SNPs, respectively. Candidate genes such as FSD2, RGA1, and AAP8 associated with salt tolerance were found to be highly differentiated and selected during the process of local adaptation to coastal habitats in SV regions. Our study highlights the importance of SVs in local adaptation; candidate genes related to salt stress and climatic adaptation to tropical and subtropical environments are important genomic resources for future breeding programs of grapevine and its rootstocks.
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Affiliation(s)
- Tianhao Zhang
- National Key Laboratory of Tropical Crop Breeding, Shenzhen Branch, Guangdong Laboratory of Lingnan Modern Agriculture, Key Laboratory of Synthetic Biology, Ministry of Agriculture and Rural Affairs, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, 518000, China
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, Guangxi University, Nanning, 530004, China
- Guangxi Key Laboratory of Forest Ecology and Conservation, Guangxi Colleges and Universities Key Laboratory for Cultivation and Utilization of Subtropical Forest Plantation, College of Forestry, Guangxi University, Nanning, 530004, China
- College of Informatics, Huazhong Agricultural University, Wuhan, 430070, China
| | - Wenjing Peng
- National Key Laboratory of Tropical Crop Breeding, Shenzhen Branch, Guangdong Laboratory of Lingnan Modern Agriculture, Key Laboratory of Synthetic Biology, Ministry of Agriculture and Rural Affairs, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, 518000, China
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, Guangxi University, Nanning, 530004, China
- Guangxi Key Laboratory of Sugarcane Biology, College of Agriculture, Guangxi University, Nanning, 530004, China
| | - Hua Xiao
- National Key Laboratory of Tropical Crop Breeding, Shenzhen Branch, Guangdong Laboratory of Lingnan Modern Agriculture, Key Laboratory of Synthetic Biology, Ministry of Agriculture and Rural Affairs, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, 518000, China
| | - Shuo Cao
- National Key Laboratory of Tropical Crop Breeding, Shenzhen Branch, Guangdong Laboratory of Lingnan Modern Agriculture, Key Laboratory of Synthetic Biology, Ministry of Agriculture and Rural Affairs, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, 518000, China
- Key Laboratory of Horticultural Plant Biology Ministry of Education, Huazhong Agricultural University, Wuhan, 430070, China
| | - Zhuyifu Chen
- National Key Laboratory of Tropical Crop Breeding, Shenzhen Branch, Guangdong Laboratory of Lingnan Modern Agriculture, Key Laboratory of Synthetic Biology, Ministry of Agriculture and Rural Affairs, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, 518000, China
| | - Xiangnian Su
- National Key Laboratory of Tropical Crop Breeding, Shenzhen Branch, Guangdong Laboratory of Lingnan Modern Agriculture, Key Laboratory of Synthetic Biology, Ministry of Agriculture and Rural Affairs, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, 518000, China
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, Guangxi University, Nanning, 530004, China
- Guangxi Key Laboratory of Forest Ecology and Conservation, Guangxi Colleges and Universities Key Laboratory for Cultivation and Utilization of Subtropical Forest Plantation, College of Forestry, Guangxi University, Nanning, 530004, China
| | - Yuanyuan Luo
- Zhengzhou Fruit Research Institute, Chinese Academy of Agricultural Sciences, Zhengzhou, 450009, China
| | - Zhongjie Liu
- National Key Laboratory of Tropical Crop Breeding, Shenzhen Branch, Guangdong Laboratory of Lingnan Modern Agriculture, Key Laboratory of Synthetic Biology, Ministry of Agriculture and Rural Affairs, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, 518000, China
| | - Yanling Peng
- National Key Laboratory of Tropical Crop Breeding, Shenzhen Branch, Guangdong Laboratory of Lingnan Modern Agriculture, Key Laboratory of Synthetic Biology, Ministry of Agriculture and Rural Affairs, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, 518000, China
| | - Xiping Yang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, Guangxi University, Nanning, 530004, China
- Guangxi Key Laboratory of Sugarcane Biology, College of Agriculture, Guangxi University, Nanning, 530004, China
| | - Guo-Feng Jiang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, Guangxi University, Nanning, 530004, China
- Guangxi Key Laboratory of Forest Ecology and Conservation, Guangxi Colleges and Universities Key Laboratory for Cultivation and Utilization of Subtropical Forest Plantation, College of Forestry, Guangxi University, Nanning, 530004, China
| | - Xiaodong Xu
- National Key Laboratory of Tropical Crop Breeding, Shenzhen Branch, Guangdong Laboratory of Lingnan Modern Agriculture, Key Laboratory of Synthetic Biology, Ministry of Agriculture and Rural Affairs, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, 518000, China
| | - Zhiyao Ma
- National Key Laboratory of Tropical Crop Breeding, Shenzhen Branch, Guangdong Laboratory of Lingnan Modern Agriculture, Key Laboratory of Synthetic Biology, Ministry of Agriculture and Rural Affairs, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, 518000, China
| | - Yongfeng Zhou
- National Key Laboratory of Tropical Crop Breeding, Shenzhen Branch, Guangdong Laboratory of Lingnan Modern Agriculture, Key Laboratory of Synthetic Biology, Ministry of Agriculture and Rural Affairs, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, 518000, China
- National Key Laboratory of Tropical Crop Breeding, Tropical Crops Genetic Resources Institute, Chinese Academy of Tropical Agricultural Sciences, Haikou, 571101, China
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Krupovic M, Kuhn JH, Fischer MG, Koonin EV. Natural history of eukaryotic DNA viruses with double jelly-roll major capsid proteins. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.03.18.585575. [PMID: 38712159 PMCID: PMC11071308 DOI: 10.1101/2024.03.18.585575] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2024]
Abstract
The phylum Preplasmiviricota (kingdom Bamfordvirae, realm Varidnaviria) is a broad assemblage of diverse viruses with comparatively short double-stranded DNA genomes (<50 kbp) that produce icosahedral capsids built from double jelly-roll major capsid proteins. Preplasmiviricots infect hosts from all cellular domains, testifying to their ancient origin and, in particular, are associated with six of the seven supergroups of eukaryotes. Preplasmiviricots comprise four major groups of viruses, namely, polintons, polinton-like viruses (PLVs), virophages, and adenovirids. We employed protein structure modeling and analysis to show that protein-primed DNA polymerases (pPolBs) of polintons, virophages, and cytoplasmic linear plasmids encompass an N-terminal domain homologous to the terminal proteins (TPs) of prokaryotic PRD1-like tectivirids and eukaryotic adenovirids that are involved in protein-primed replication initiation, followed by a viral ovarian tumor-like cysteine deubiquitinylase (vOTU) domain. The vOTU domain is likely responsible for the cleavage of the TP from the large pPolB polypeptide and is inactivated in adenovirids, in which TP is a separate protein. Many PLVs and transpovirons encode a distinct derivative of polinton-like pPolB that retains the TP, vOTU and pPolB polymerization palm domains but lacks the exonuclease domain and instead contains a supefamily 1 helicase domain. Analysis of the presence/absence and inactivation of the vOTU domains, and replacement of pPolB with other DNA polymerases in eukaryotic preplasmiviricots enabled us to outline a complete scenario for their origin and evolution.
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Affiliation(s)
- Mart Krupovic
- Institut Pasteur, Université Paris Cité, Archaeal Virology Unit, Paris, France
| | - Jens H. Kuhn
- Integrated Research Facility at Fort Detrick, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Fort Detrick, Frederick, Maryland, USA
| | - Matthias G. Fischer
- Department of Biomolecular Mechanisms, Max Planck Institute for Medical Research, Heidelberg, Germany
| | - Eugene V. Koonin
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, Maryland, USA
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8
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Yutin N, Mutz P, Krupovic M, Koonin EV. Mriyaviruses: Small Relatives of Giant Viruses. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.02.29.582850. [PMID: 38529486 PMCID: PMC10962738 DOI: 10.1101/2024.02.29.582850] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/27/2024]
Abstract
The phylum Nucleocytoviricota consists of large and giant viruses that range in genome size from about 100 kilobases (kb) to more than 2.5 megabases. Here, using metagenome mining followed by extensive phylogenomic analysis and protein structure comparison, we delineate a distinct group of viruses with double-stranded (ds) DNA genomes in the range of 35-45 kb that appear to be related to the Nucleocytoviricota. In phylogenetic trees of the conserved double jelly-roll major capsid proteins (MCP) and DNA packaging ATPases, these viruses do not show affinity to any particular branch of the Nucleocytoviricota and accordingly would comprise a class which we propose to name "Mriyaviricetes" (after Ukrainian Mriya, dream). Structural comparison of the MCP suggests that, among the extant virus lineages, mriyaviruses are the closest one to the ancestor of the Nucleocytoviricota. In the phylogenetic trees, mriyaviruses split into two well-separated branches, the family Yaraviridae and proposed new family "Gamadviridae". The previously characterized members of these families, Yaravirus and Pleurochrysis sp. endemic viruses, infect amoeba and haptophytes, respectively. The genomes of the rest of the mriyaviruses were assembled from metagenomes from diverse environments, suggesting that mriyaviruses infect various unicellular eukaryotes. Mriyaviruses lack DNA polymerase, which is encoded by all other members of the Nucleocytoviricota, and RNA polymerase subunits encoded by all cytoplasmic viruses among the Nucleocytoviricota, suggesting that they replicate in the host cell nuclei. All mriyaviruses encode a HUH superfamily endonuclease that is likely to be essential for the initiation of virus DNA replication via the rolling circle mechanism.
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Affiliation(s)
- Natalya Yutin
- National Center for Biotechnology Information, National Library of Medicine, Bethesda, MD 20894, USA
| | - Pascal Mutz
- National Center for Biotechnology Information, National Library of Medicine, Bethesda, MD 20894, USA
| | - Mart Krupovic
- Institut Pasteur, Université Paris Cité, Archaeal Virology Unit, Paris 75015, France
| | - Eugene V. Koonin
- National Center for Biotechnology Information, National Library of Medicine, Bethesda, MD 20894, USA
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9
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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.
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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
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10
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Hawkins DEDP, Godwin OC, Antson AA. Viral Genomic DNA Packaging Machinery. Subcell Biochem 2024; 104:181-205. [PMID: 38963488 DOI: 10.1007/978-3-031-58843-3_9] [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] [Indexed: 07/05/2024]
Abstract
Tailed double-stranded DNA bacteriophage employs a protein terminase motor to package their genome into a preformed protein shell-a system shared with eukaryotic dsDNA viruses such as herpesviruses. DNA packaging motor proteins represent excellent targets for antiviral therapy, with Letermovir, which binds Cytomegalovirus terminase, already licensed as an effective prophylaxis. In the realm of bacterial viruses, these DNA packaging motors comprise three protein constituents: the portal protein, small terminase and large terminase. The portal protein guards the passage of DNA into the preformed protein shell and acts as a protein interaction hub throughout viral assembly. Small terminase recognises the viral DNA and recruits large terminase, which in turn pumps DNA in an ATP-dependent manner. Large terminase also cleaves DNA at the termination of packaging. Multiple high-resolution structures of each component have been resolved for different phages, but it is only more recently that the field has moved towards cryo-EM reconstructions of protein complexes. In conjunction with highly informative single-particle studies of packaging kinetics, these structures have begun to inspire models for the packaging process and its place among other DNA machines.
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Affiliation(s)
- Dorothy E D P Hawkins
- York Structural Biology Laboratory, Department of Chemistry, University of York, York, UK.
| | - Owen C Godwin
- York Structural Biology Laboratory, Department of Chemistry, University of York, York, UK
- Structural Biology, The Francis Crick Institute, London, UK
| | - Alfred A Antson
- York Structural Biology Laboratory, Department of Chemistry, University of York, York, UK.
- Structural Biology, The Francis Crick Institute, London, UK.
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11
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Potapov SA, Belykh OI. Virophages Found in Viromes from Lake Baikal. Biomolecules 2023; 13:1773. [PMID: 38136644 PMCID: PMC10741620 DOI: 10.3390/biom13121773] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2023] [Revised: 12/04/2023] [Accepted: 12/06/2023] [Indexed: 12/24/2023] Open
Abstract
In this study, a previously little-studied group of viruses-virophages-was searched for and identified in the viromes of the ancient oligotrophic Lake Baikal. Virophages are small dsDNA viruses that parasitize giant viruses (e.g., Mimiviridae), which in turn affect unicellular eukaryotes. We analyzed eight viromes obtained from the deep-water areas of three basins of Lake Baikal and the shallow-water strait Maloye More in different seasons. The sequences of virophages were revealed in all viromes and were dominant after bacteriophages and algal viruses. Sixteen putative complete genomes of virophages were assembled, all of which contained four conserved genes encoding major capsid protein (MCP), minor capsid protein (mCP), maturation cysteine protease (PRO), and FtsK-HerA family DNA-packaging ATPase (ATPase). The MCP-based cluster analysis showed a sequence separation according to seasons, and a dependence on the geographical localization was not detected.
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Affiliation(s)
- Sergey Anatoljevich Potapov
- Limnological Institute Siberian Branch of the Russian Academy of Sciences, Ulan-Batorskaya 3, Irkutsk 664033, Russia;
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12
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Jeong DE, Sundrani S, Hall RN, Krupovic M, Koonin EV, Fire AZ. DNA Polymerase Diversity Reveals Multiple Incursions of Polintons During Nematode Evolution. Mol Biol Evol 2023; 40:msad274. [PMID: 38069639 DOI: 10.1093/molbev/msad274] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2023] [Revised: 11/01/2023] [Accepted: 12/04/2023] [Indexed: 12/19/2023] Open
Abstract
Polintons are double-stranded DNA, virus-like self-synthesizing transposons widely found in eukaryotic genomes. Recent metagenomic discoveries of Polinton-like viruses are consistent with the hypothesis that Polintons invade eukaryotic host genomes through infectious viral particles. Nematode genomes contain multiple copies of Polintons and provide an opportunity to explore the natural distribution and evolution of Polintons during this process. We performed an extensive search of Polintons across nematode genomes, identifying multiple full-length Polinton copies in several species. We provide evidence of both ancient Polinton integrations and recent mobility in strains of the same nematode species. In addition to the major nematode Polinton family, we identified a group of Polintons that are overall closely related to the major family but encode a distinct protein-primed DNA polymerase B (pPolB) that is related to homologs from a different group of Polintons present outside of the Nematoda. Phylogenetic analyses on the pPolBs support the evolutionary scenarios in which these extrinsic pPolBs that seem to derive from Polinton families present in oomycetes and molluscs replaced the canonical pPolB in subsets of Polintons found in terrestrial and marine nematodes, respectively, suggesting interphylum horizontal gene transfers. The pPolBs of the terrestrial nematode and oomycete Polintons share a unique feature, an insertion of an HNH nuclease domain, whereas the pPolBs in the marine nematode Polintons share an insertion of a VSR nuclease domain with marine mollusc pPolBs. We hypothesize that horizontal gene transfer occurs among Polintons from widely different but cohabiting hosts.
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Affiliation(s)
- Dae-Eun Jeong
- Department of Pathology, Stanford University School of Medicine, Stanford, CA, USA
| | - Sameer Sundrani
- Department of Bioengineering, Stanford University, Stanford, CA, USA
- Present address: Department of Biomedical Informatics, Vanderbilt University School of Medicine, Nashville, TN, USA
| | | | - Mart Krupovic
- Institut Pasteur, Université Paris Cité, Archaeal Virology Unit, Paris, France
| | - Eugene V Koonin
- National National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, MD, USA
| | - Andrew Z Fire
- Department of Pathology, Stanford University School of Medicine, Stanford, CA, USA
- Department of Genetics, Stanford University School of Medicine, Stanford, CA, USA
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13
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Wei Y, Gong Z, Han GZ. Plants acquired mitochondrial linear plasmids horizontally from fungi likely during the conquest of land. Mob DNA 2023; 14:15. [PMID: 37849012 PMCID: PMC10583447 DOI: 10.1186/s13100-023-00304-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2023] [Accepted: 10/11/2023] [Indexed: 10/19/2023] Open
Abstract
Mitochondrial linear plasmids have been sporadically reported in fungi and plants. Yet, much remains obscure about the diversity, distribution, and evolution of mitochondrial linear plasmids. Here, through phylogenomic analyses across 7,163 cellular organisms (including 991 plants), we find that mitochondrial linear plasmids are widely present in land plants and fungi. Phylogenetic analyses indicate that plants are likely to have acquired mitochondrial linear plasmids horizontally from fungi before or during the conquest of terrestrial environments by plants. Gene content analyses show that mitochondrial linear plasmids harbor a highly dynamic and promiscuous repertoire of genes. Our study refines the understanding of the origin and evolution of mitochondrial linear plasmids.
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Affiliation(s)
- Yutong Wei
- College of Life Sciences, Nanjing Normal University, Nanjing, 210023, Jiangsu, China
| | - Zhen Gong
- College of Life Sciences, Nanjing Normal University, Nanjing, 210023, Jiangsu, China
| | - Guan-Zhu Han
- College of Life Sciences, Nanjing Normal University, Nanjing, 210023, Jiangsu, China.
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14
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Marinov GK, Chen X, Swaffer MP, Xiang T, Grossman AR, Greenleaf WJ. Genome-wide distribution of 5-hydroxymethyluracil and chromatin accessibility in the Breviolum minutum genome. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.09.18.558303. [PMID: 37781619 PMCID: PMC10541103 DOI: 10.1101/2023.09.18.558303] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/03/2023]
Abstract
In dinoflagellates, a unique and extremely divergent genomic and nuclear organization has evolved. The highly unusual features of dinoflagellate nuclei and genomes include permanently condensed liquid crystalline chromosomes, primarily packaged by proteins other than histones, genes organized in very long unidirectional gene arrays, a general absence of transcriptional regulation, high abundance of the otherwise very rare DNA modification 5-hydroxymethyluracil (5-hmU), and many others. While most of these fascinating properties were originally identified in the 1970s and 1980s, they have not yet been investigated using modern genomic tools. In this work, we address some of the outstanding questions regarding dinoflagellate genome organization by mapping the genome-wide distribution of 5-hmU (using both immunoprecipitation-based and basepair-resolution chemical mapping approaches) and of chromatin accessibility in the genome of the Symbiodiniaceae dinoflagellate Breviolum minutum. We find that the 5-hmU modification is preferentially enriched over certain classes of repetitive elements, often coincides with the boundaries between gene arrays, and is generally correlated with decreased chromatin accessibility, the latter otherwise being largely uniform along the genome. We discuss the potential roles of 5-hmU in the functional organization of dinoflagellate genomes and its relationship to the transcriptional landscape of gene arrays.
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Affiliation(s)
- Georgi K Marinov
- Department of Genetics, Stanford University, Stanford, California 94305, USA
| | - Xinyi Chen
- Department of Bioengineering, Stanford University, Stanford, California 94305, USA
| | | | - Tingting Xiang
- Department of Plant Biology, Carnegie Institution for Science, Stanford, California 94305, USA
| | - Arthur R Grossman
- Department of Plant Biology, Carnegie Institution for Science, Stanford, California 94305, USA
| | - William J Greenleaf
- Department of Genetics, Stanford University, Stanford, California 94305, USA
- Center for Personal Dynamic Regulomes, Stanford University, Stanford, California 94305, USA
- Department of Applied Physics, Stanford University, Stanford, California 94305, USA
- Chan Zuckerberg Biohub, San Francisco, California, USA
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15
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Liao X, Zhu W, Zhou J, Li H, Xu X, Zhang B, Gao X. Repetitive DNA sequence detection and its role in the human genome. Commun Biol 2023; 6:954. [PMID: 37726397 PMCID: PMC10509279 DOI: 10.1038/s42003-023-05322-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2023] [Accepted: 09/04/2023] [Indexed: 09/21/2023] Open
Abstract
Repetitive DNA sequences playing critical roles in driving evolution, inducing variation, and regulating gene expression. In this review, we summarized the definition, arrangement, and structural characteristics of repeats. Besides, we introduced diverse biological functions of repeats and reviewed existing methods for automatic repeat detection, classification, and masking. Finally, we analyzed the type, structure, and regulation of repeats in the human genome and their role in the induction of complex diseases. We believe that this review will facilitate a comprehensive understanding of repeats and provide guidance for repeat annotation and in-depth exploration of its association with human diseases.
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Affiliation(s)
- Xingyu Liao
- Computational Bioscience Research Center (CBRC), Computer, Electrical and Mathematical Sciences and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal, 23955, Saudi Arabia
| | - Wufei Zhu
- Department of Endocrinology, Yichang Central People's Hospital, The First College of Clinical Medical Science, China Three Gorges University, 443000, Yichang, P.R. China
| | - Juexiao Zhou
- Computational Bioscience Research Center (CBRC), Computer, Electrical and Mathematical Sciences and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal, 23955, Saudi Arabia
| | - Haoyang Li
- Computational Bioscience Research Center (CBRC), Computer, Electrical and Mathematical Sciences and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal, 23955, Saudi Arabia
| | - Xiaopeng Xu
- Computational Bioscience Research Center (CBRC), Computer, Electrical and Mathematical Sciences and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal, 23955, Saudi Arabia
| | - Bin Zhang
- Computational Bioscience Research Center (CBRC), Computer, Electrical and Mathematical Sciences and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal, 23955, Saudi Arabia
| | - Xin Gao
- Computational Bioscience Research Center (CBRC), Computer, Electrical and Mathematical Sciences and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal, 23955, Saudi Arabia.
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16
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Jeong DE, Sundrani S, Hall RN, Krupovic M, Koonin EV, Fire AZ. DNA polymerase diversity reveals multiple incursions of Polintons during nematode evolution. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.08.22.554363. [PMID: 37662302 PMCID: PMC10473752 DOI: 10.1101/2023.08.22.554363] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/05/2023]
Abstract
Polintons are dsDNA, virus-like self-synthesizing transposons widely found in eukaryotic genomes. Recent metagenomic discoveries of Polinton-like viruses are consistent with the hypothesis that Polintons invade eukaryotic host genomes through infectious viral particles. Nematode genomes contain multiple copies of Polintons and provide an opportunity to explore the natural distribution and evolution of Polintons during this process. We performed an extensive search of Polintons across nematode genomes, identifying multiple full-length Polinton copies in several species. We provide evidence of both ancient Polinton integrations and recent mobility in strains of the same nematode species. In addition to the major nematode Polinton family, we identified a group of Polintons that are overall closely related to the major family, but encode a distinct protein-primed B family DNA polymerase (pPolB) that is related to homologs from a different group of Polintons present outside of the Nematoda . Phylogenetic analyses on the pPolBs support the evolutionary scenarios in which these extrinsic pPolBs that seem to derive from Polinton families present in oomycetes and molluscs replaced the canonical pPolB in subsets of Polintons found in terrestrial and marine nematodes, respectively, suggesting inter-phylum horizontal gene transfers. The pPolBs of the terrestrial nematode and oomycete Polintons share a unique feature, an insertion of a HNH nuclease domain, whereas the pPolBs in the marine nematode Polintons share an insertion of a VSR nuclease domain with marine mollusc pPolBs. We hypothesize that horizontal gene transfer occurs among Polintons from widely different but cohabiting hosts.
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17
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Chakrabarty P, Sen R, Sengupta S. From parasites to partners: exploring the intricacies of host-transposon dynamics and coevolution. Funct Integr Genomics 2023; 23:278. [PMID: 37610667 DOI: 10.1007/s10142-023-01206-w] [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: 06/14/2023] [Revised: 08/01/2023] [Accepted: 08/07/2023] [Indexed: 08/24/2023]
Abstract
Transposable elements, often referred to as "jumping genes," have long been recognized as genomic parasites due to their ability to integrate and disrupt normal gene function and induce extensive genomic alterations, thereby compromising the host's fitness. To counteract this, the host has evolved a plethora of mechanisms to suppress the activity of the transposons. Recent research has unveiled the host-transposon relationships to be nuanced and complex phenomena, resulting in the coevolution of both entities. Transposition increases the mutational rate in the host genome, often triggering physiological pathways such as immune and stress responses. Current gene transfer technologies utilizing transposable elements have potential drawbacks, including off-target integration, induction of mutations, and modifications of cellular machinery, which makes an in-depth understanding of the host-transposon relationship imperative. This review highlights the dynamic interplay between the host and transposable elements, encompassing various factors and components of the cellular machinery. We provide a comprehensive discussion of the strategies employed by transposable elements for their propagation, as well as the mechanisms utilized by the host to mitigate their parasitic effects. Additionally, we present an overview of recent research identifying host proteins that act as facilitators or inhibitors of transposition. We further discuss the evolutionary outcomes resulting from the genetic interactions between the host and the transposable elements. Finally, we pose open questions in this field and suggest potential avenues for future research.
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Affiliation(s)
- Prayas Chakrabarty
- Department of Life Sciences, Presidency University Kolkata, 86/1 College Street, Kolkata, 700073, India
| | - Raneet Sen
- Department of Life Sciences, Presidency University Kolkata, 86/1 College Street, Kolkata, 700073, India
- Institute of Bioorganic Chemistry, Department of RNA Metabolism, Polish Academy of Sciences, Poznan, Poland
| | - Sugopa Sengupta
- Department of Life Sciences, Presidency University Kolkata, 86/1 College Street, Kolkata, 700073, India.
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18
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Widen SA, Bes IC, Koreshova A, Pliota P, Krogull D, Burga A. Virus-like transposons cross the species barrier and drive the evolution of genetic incompatibilities. Science 2023; 380:eade0705. [PMID: 37384706 DOI: 10.1126/science.ade0705] [Citation(s) in RCA: 15] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2022] [Accepted: 05/17/2023] [Indexed: 07/01/2023]
Abstract
Horizontal gene transfer, the movement of genetic material between species, has been reported across all major eukaryotic lineages. However, the underlying mechanisms of transfer and their impact on genome evolution are still poorly understood. While studying the evolutionary origin of a selfish element in the nematode Caenorhabditis briggsae, we discovered that Mavericks, ancient virus-like transposons related to giant viruses and virophages, are one of the long-sought vectors of horizontal gene transfer. We found that Mavericks gained a novel herpesvirus-like fusogen in nematodes, leading to the widespread exchange of cargo genes between extremely divergent species, bypassing sexual and genetic barriers spanning hundreds of millions of years. Our results show how the union between viruses and transposons causes horizontal gene transfer and ultimately genetic incompatibilities in natural populations.
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Affiliation(s)
- Sonya A Widen
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna BioCenter (VBC), 1030 Vienna, Austria
| | - Israel Campo Bes
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna BioCenter (VBC), 1030 Vienna, Austria
| | - Alevtina Koreshova
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna BioCenter (VBC), 1030 Vienna, Austria
- Vienna BioCenter PhD Program, Doctoral School of the University of Vienna and Medical University of Vienna, A-1030 Vienna, Austria
| | - Pinelopi Pliota
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna BioCenter (VBC), 1030 Vienna, Austria
| | - Daniel Krogull
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna BioCenter (VBC), 1030 Vienna, Austria
- Vienna BioCenter PhD Program, Doctoral School of the University of Vienna and Medical University of Vienna, A-1030 Vienna, Austria
| | - Alejandro Burga
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna BioCenter (VBC), 1030 Vienna, Austria
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19
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Barreat JGN, Katzourakis A. A billion years arms-race between viruses, virophages, and eukaryotes. eLife 2023; 12:RP86617. [PMID: 37358563 DOI: 10.7554/elife.86617] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/27/2023] Open
Abstract
Bamfordviruses are arguably the most diverse group of viruses infecting eukaryotes. They include the Nucleocytoplasmic Large DNA viruses (NCLDVs), virophages, adenoviruses, Mavericks and Polinton-like viruses. Two main hypotheses for their origins have been proposed: the 'nuclear-escape' and 'virophage-first' hypotheses. The nuclear-escape hypothesis proposes an endogenous, Maverick-like ancestor which escaped from the nucleus and gave rise to adenoviruses and NCLDVs. In contrast, the virophage-first hypothesis proposes that NCLDVs coevolved with protovirophages; Mavericks then evolved from virophages that became endogenous, with adenoviruses escaping from the nucleus at a later stage. Here, we test the predictions made by both models and consider alternative evolutionary scenarios. We use a data set of the four core virion proteins sampled across the diversity of the lineage, together with Bayesian and maximum-likelihood hypothesis-testing methods, and estimate rooted phylogenies. We find strong evidence that adenoviruses and NCLDVs are not sister groups, and that Mavericks and Mavirus acquired the rve-integrase independently. We also found strong support for a monophyletic group of virophages (family Lavidaviridae) and a most likely root placed between virophages and the other lineages. Our observations support alternatives to the nuclear-escape scenario and a billion years evolutionary arms-race between virophages and NCLDVs.
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Affiliation(s)
| | - Aris Katzourakis
- Department of Biology, University of Oxford, Oxford, United Kingdom
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20
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Krupovic M, Dolja VV, Koonin EV. The virome of the last eukaryotic common ancestor and eukaryogenesis. Nat Microbiol 2023; 8:1008-1017. [PMID: 37127702 PMCID: PMC11130978 DOI: 10.1038/s41564-023-01378-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2022] [Accepted: 03/29/2023] [Indexed: 05/03/2023]
Abstract
All extant eukaryotes descend from the last eukaryotic common ancestor (LECA), which is thought to have featured complex cellular organization. To gain insight into LECA biology and eukaryogenesis-the origin of the eukaryotic cell, which remains poorly understood-we reconstructed the LECA virus repertoire. We compiled an inventory of eukaryotic hosts of all major virus taxa and reconstructed the LECA virome by inferring the origins of these groups of viruses. The origin of the LECA virome can be traced back to a small set of bacterial-not archaeal-viruses. This provenance of the LECA virome is probably due to the bacterial origin of eukaryotic membranes, which is most compatible with two endosymbiosis events in a syntrophic model of eukaryogenesis. In the first endosymbiosis, a bacterial host engulfed an Asgard archaeon, preventing archaeal viruses from entry owing to a lack of archaeal virus receptors on the external membranes.
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Affiliation(s)
- Mart Krupovic
- Institut Pasteur, Université Paris Cité, CNRS UMR6047, Archaeal Virology Unit, Paris, France.
| | - Valerian V Dolja
- Department of Botany and Plant Pathology, Oregon State University, Corvallis, OR, USA
| | - Eugene V Koonin
- National Center for Biotechnology Information, National Library of Medicine, Bethesda, MD, USA.
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21
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Moniruzzaman M, Aylward FO. Endogenous DNA viruses take center stage in eukaryotic genome evolution. Proc Natl Acad Sci U S A 2023; 120:e2305212120. [PMID: 37186839 PMCID: PMC10214139 DOI: 10.1073/pnas.2305212120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/17/2023] Open
Affiliation(s)
- Mohammad Moniruzzaman
- Department of Marine Biology and Ecology, Rosenstiel School of Marine, Atmospheric, and Earth Science, University of Miami, Coral Gables, FL33149
| | - Frank O. Aylward
- Department of Biological Sciences, Virginia Tech, Blacksburg, VA24061
- Center for Emerging, Zoonotic, and Arthropod-Borne Infectious Disease, Virginia Tech, Blacksburg, VA24061
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22
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Inoue Y, Takeda H. Teratorn and its relatives - a cross-point of distinct mobile elements, transposons and viruses. Front Vet Sci 2023; 10:1158023. [PMID: 37187934 PMCID: PMC10175614 DOI: 10.3389/fvets.2023.1158023] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2023] [Accepted: 04/10/2023] [Indexed: 05/17/2023] Open
Abstract
Mobile genetic elements (e.g., transposable elements and plasmids) and viruses display significant diversity with various life cycles, but how this diversity emerges remains obscure. We previously reported a novel and giant (180 kb long) mobile element, Teratorn, originally identified in the genome of medaka, Oryzias latipes. Teratorn is a composite DNA transposon created by a fusion of a piggyBac-like DNA transposon (piggyBac) and a novel herpesvirus of the Alloherpesviridae family. Genomic survey revealed that Teratorn-like herpesviruses are widely distributed among teleost genomes, the majority of which are also fused with piggyBac, suggesting that fusion with piggyBac is a trigger for the life-cycle shift of authentic herpesviruses to an intragenomic parasite. Thus, Teratorn-like herpesvirus provides a clear example of how novel mobile elements emerge, that is to say, the creation of diversity. In this review, we discuss the unique sequence and life-cycle characteristics of Teratorn, followed by the evolutionary process of piggyBac-herpesvirus fusion based on the distribution of Teratorn-like herpesviruses (relatives) among teleosts. Finally, we provide other examples of evolutionary associations between different classes of elements and propose that recombination could be a driving force generating novel mobile elements.
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Affiliation(s)
- Yusuke Inoue
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Tokyo, Japan
| | - Hiroyuki Takeda
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Tokyo, Japan
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23
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Zhao Z, Huang Y, Liu C, Zhu D, Gao S, Liu S, Peng R, Zhang Y, Huang X, Qi J, Wong CCL, Zhang X, Wang P, Qin Q, Gao GF. Near-atomic architecture of Singapore grouper iridovirus and implications for giant virus assembly. Nat Commun 2023; 14:2050. [PMID: 37041173 PMCID: PMC10090177 DOI: 10.1038/s41467-023-37681-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2022] [Accepted: 03/28/2023] [Indexed: 04/13/2023] Open
Abstract
Singapore grouper iridovirus (SGIV), one of the nucleocytoviricota viruses (NCVs), is a highly pathogenic iridovirid. SGIV infection results in massive economic losses to the aquaculture industry and significantly threatens global biodiversity. In recent years, high morbidity and mortality in aquatic animals have been caused by iridovirid infections worldwide. Effective control and prevention strategies are urgently needed. Here, we present a near-atomic architecture of the SGIV capsid and identify eight types of capsid proteins. The viral inner membrane-integrated anchor protein colocalizes with the endoplasmic reticulum (ER), supporting the hypothesis that the biogenesis of the inner membrane is associated with the ER. Additionally, immunofluorescence assays indicate minor capsid proteins (mCPs) could form various building blocks with major capsid proteins (MCPs) before the formation of a viral factory (VF). These results expand our understanding of the capsid assembly of NCVs and provide more targets for vaccine and drug design to fight iridovirid infections.
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Affiliation(s)
- Zhennan Zhao
- CAS Key Laboratory of Pathogen Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China
| | - Youhua Huang
- College of Marine Sciences, South China Agricultural University, Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou, 510642, China
| | - Congcong Liu
- Cryo-EM Center, Department of Biology, Southern University of Science and Technology, Shenzhen, 518055, China
- Institute for Hepatology, National Clinical Research Center for Infectious Disease, Shenzhen Third People's Hospital, Shenzhen, 518112, China
| | - Dongjie Zhu
- School of Life Science, University of Science and Technology of China, Hefei, 230026, China
- National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, 100101, China
| | - Shuaixin Gao
- Clinical Research Institute, State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Science & Peking Union Medical College, Beijing, 100730, China
- Department of Human Sciences & James Comprehensive Cancer Center, The Ohio State University, Columbus, 43210, USA
| | - Sheng Liu
- Cryo-EM Center, Department of Biology, Southern University of Science and Technology, Shenzhen, 518055, China
| | - Ruchao Peng
- CAS Key Laboratory of Pathogen Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China
- Perelman School of Medicine, University of Pennsylvania, Philadelphia, 19104, USA
| | - Ya Zhang
- College of Marine Sciences, South China Agricultural University, Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou, 510642, China
| | - Xiaohong Huang
- College of Marine Sciences, South China Agricultural University, Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou, 510642, China
| | - Jianxun Qi
- CAS Key Laboratory of Pathogen Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China.
- University of Chinese Academy of Sciences, Beijing, 100049, China.
- Beijing Life Science Academy, Beijing, 102209, China.
| | - Catherine C L Wong
- Clinical Research Institute, State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Science & Peking Union Medical College, Beijing, 100730, China.
| | - Xinzheng Zhang
- National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, 100101, China.
- University of Chinese Academy of Sciences, Beijing, 100049, China.
| | - Peiyi Wang
- Cryo-EM Center, Department of Biology, Southern University of Science and Technology, Shenzhen, 518055, China.
| | - Qiwei Qin
- College of Marine Sciences, South China Agricultural University, Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou, 510642, China.
| | - George F Gao
- CAS Key Laboratory of Pathogen Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China.
- University of Chinese Academy of Sciences, Beijing, 100049, China.
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24
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Gaïa M, Meng L, Pelletier E, Forterre P, Vanni C, Fernandez-Guerra A, Jaillon O, Wincker P, Ogata H, Krupovic M, Delmont TO. Mirusviruses link herpesviruses to giant viruses. Nature 2023; 616:783-789. [PMID: 37076623 PMCID: PMC10132985 DOI: 10.1038/s41586-023-05962-4] [Citation(s) in RCA: 22] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2022] [Accepted: 03/16/2023] [Indexed: 04/21/2023]
Abstract
DNA viruses have a major influence on the ecology and evolution of cellular organisms1-4, but their overall diversity and evolutionary trajectories remain elusive5. Here we carried out a phylogeny-guided genome-resolved metagenomic survey of the sunlit oceans and discovered plankton-infecting relatives of herpesviruses that form a putative new phylum dubbed Mirusviricota. The virion morphogenesis module of this large monophyletic clade is typical of viruses from the realm Duplodnaviria6, with multiple components strongly indicating a common ancestry with animal-infecting Herpesvirales. Yet, a substantial fraction of mirusvirus genes, including hallmark transcription machinery genes missing in herpesviruses, are closely related homologues of giant eukaryotic DNA viruses from another viral realm, Varidnaviria. These remarkable chimaeric attributes connecting Mirusviricota to herpesviruses and giant eukaryotic viruses are supported by more than 100 environmental mirusvirus genomes, including a near-complete contiguous genome of 432 kilobases. Moreover, mirusviruses are among the most abundant and active eukaryotic viruses characterized in the sunlit oceans, encoding a diverse array of functions used during the infection of microbial eukaryotes from pole to pole. The prevalence, functional activity, diversification and atypical chimaeric attributes of mirusviruses point to a lasting role of Mirusviricota in the ecology of marine ecosystems and in the evolution of eukaryotic DNA viruses.
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Affiliation(s)
- Morgan Gaïa
- Génomique Métabolique, Genoscope, Institut François Jacob, CEA, CNRS, Univ. Evry, Université Paris-Saclay, Evry, France
- Research Federation for the Study of Global Ocean Systems Ecology and Evolution, FR2022/Tara GOSEE, Paris, France
| | - Lingjie Meng
- Bioinformatics Center, Institute for Chemical Research, Kyoto University, Uji, Japan
| | - Eric Pelletier
- Génomique Métabolique, Genoscope, Institut François Jacob, CEA, CNRS, Univ. Evry, Université Paris-Saclay, Evry, France
- Research Federation for the Study of Global Ocean Systems Ecology and Evolution, FR2022/Tara GOSEE, Paris, France
| | - Patrick Forterre
- Institut de Biologie Intégrative de la Cellule (I2BC), CNRS, Université Paris-Saclay, Gif sur Yvette, France
- Département de Microbiologie, Institut Pasteur, Paris, France
| | - Chiara Vanni
- MARUM Center for Marine Environmental Sciences, University of Bremen, Bremen, Germany
| | - Antonio Fernandez-Guerra
- Lundbeck Foundation GeoGenetics Centre, GLOBE Institute, University of Copenhagen, Copenhagen, Denmark
| | - Olivier Jaillon
- Génomique Métabolique, Genoscope, Institut François Jacob, CEA, CNRS, Univ. Evry, Université Paris-Saclay, Evry, France
- Research Federation for the Study of Global Ocean Systems Ecology and Evolution, FR2022/Tara GOSEE, Paris, France
| | - Patrick Wincker
- Génomique Métabolique, Genoscope, Institut François Jacob, CEA, CNRS, Univ. Evry, Université Paris-Saclay, Evry, France
- Research Federation for the Study of Global Ocean Systems Ecology and Evolution, FR2022/Tara GOSEE, Paris, France
| | - Hiroyuki Ogata
- Bioinformatics Center, Institute for Chemical Research, Kyoto University, Uji, Japan
| | - Mart Krupovic
- Institut Pasteur, Université Paris Cité, CNRS UMR6047, Archaeal Virology Unit, Paris, France
| | - Tom O Delmont
- Génomique Métabolique, Genoscope, Institut François Jacob, CEA, CNRS, Univ. Evry, Université Paris-Saclay, Evry, France.
- Research Federation for the Study of Global Ocean Systems Ecology and Evolution, FR2022/Tara GOSEE, Paris, France.
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25
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Inoue Y, Takeda H. Teratorn and Its Related Elements – a Novel Group of Herpesviruses Widespread in Teleost Genomes. Zoolog Sci 2023; 40:83-90. [PMID: 37042688 DOI: 10.2108/zs220069] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2022] [Accepted: 12/12/2022] [Indexed: 03/08/2023]
Abstract
Herpesviruses are a large family of DNA viruses infecting vertebrates and invertebrates, and are important pathogens in the field of aquaculture. In general, herpesviruses do not have the ability to integrate into the host genomes since they do not have a chromosomal integration step in their life cycles. Recently, we identified a novel group of herpesviruses, "Teratorn" and its related elements, in the genomes of various teleost fish species. At least some of the Teratorn-like herpesviruses are fused with a piggyBac-like DNA transposon, suggesting that they have acquired the transposon-like intragenomic lifestyle by hijacking the transposon system. In this review, we describe the sequence characteristics of Teratorn-like herpesviruses and phylogenetic relationships with other herpesviruses. Then we discuss the process of transposon-herpesvirus fusion, their life cycle, and the generality of transposon-virus fusion. Teratorn-like herpesviruses provide a piece of concrete evidence that even non-retroviral elements can become intragenomic parasites retaining replication capacity, by acquiring transposition machinery from other sources.
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Affiliation(s)
- Yusuke Inoue
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Hiroyuki Takeda
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
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26
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Roitman S, Rozenberg A, Lavy T, Brussaard CPD, Kleifeld O, Béjà O. Isolation and infection cycle of a polinton-like virus virophage in an abundant marine alga. Nat Microbiol 2023; 8:332-346. [PMID: 36702941 DOI: 10.1038/s41564-022-01305-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2022] [Accepted: 12/13/2022] [Indexed: 01/27/2023]
Abstract
Virophages are small double stranded DNA (dsDNA) viruses that can only replicate in a host by co-infecting with another virus. Marine algae are commonly associated with virophage-like elements such as Polinton-like viruses (PLVs) that remain largely uncharacterized. Here we isolated a PLV that co-infects the alga Phaeocystis globosa with the Phaeocystis globosa virus-14T (PgV-14T), a close relative of the "Phaeocystis globosa virus-virophage" genomic sequence. We name this PLV 'Gezel-14T. Gezel is phylogenetically distinct from the Lavidaviridae family where all known virophages belong. Gezel-14T co-infection decreases the fitness of its viral host by reducing burst sizes of PgV-14T, yet insufficiently to spare the cellular host population. Genomic screens show Gezel-14T-like PLVs integrated into Phaeocystis genomes, suggesting that these widespread viruses are capable of integration into cellular host genomes. This system presents an opportunity to better understand the evolution of eukaryotic dsDNA viruses as well as the complex dynamics and implications of viral parasitism.
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Affiliation(s)
- Sheila Roitman
- Faculty of Biology, Technion - Israel Institute of Technology, Haifa, Israel.
| | - Andrey Rozenberg
- Faculty of Biology, Technion - Israel Institute of Technology, Haifa, Israel
| | - Tali Lavy
- Faculty of Biology, Technion - Israel Institute of Technology, Haifa, Israel
| | - Corina P D Brussaard
- Department of Marine Microbiology and Biogeochemistry, NIOZ Royal Netherlands Institute for Sea Research, Texel, The Netherlands
- Institute for Biodiversity and Ecosystem Dynamics (IBED), University of Amsterdam, Amsterdam, The Netherlands
| | - Oded Kleifeld
- Faculty of Biology, Technion - Israel Institute of Technology, Haifa, Israel
| | - Oded Béjà
- Faculty of Biology, Technion - Israel Institute of Technology, Haifa, Israel.
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27
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Roux S, Fischer MG, Hackl T, Katz LA, Schulz F, Yutin N. Updated Virophage Taxonomy and Distinction from Polinton-like Viruses. Biomolecules 2023; 13:204. [PMID: 36830574 PMCID: PMC9952930 DOI: 10.3390/biom13020204] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2022] [Revised: 01/02/2023] [Accepted: 01/04/2023] [Indexed: 01/20/2023] Open
Abstract
Virophages are small dsDNA viruses that hijack the machinery of giant viruses during the co-infection of a protist (i.e., microeukaryotic) host and represent an exceptional case of "hyperparasitism" in the viral world. While only a handful of virophages have been isolated, a vast diversity of virophage-like sequences have been uncovered from diverse metagenomes. Their wide ecological distribution, idiosyncratic infection and replication strategy, ability to integrate into protist and giant virus genomes and potential role in antiviral defense have made virophages a topic of broad interest. However, one limitation for further studies is the lack of clarity regarding the nomenclature and taxonomy of this group of viruses. Specifically, virophages have been linked in the literature to other "virophage-like" mobile genetic elements and viruses, including polinton-like viruses (PLVs), but there are no formal demarcation criteria and proper nomenclature for either group, i.e., virophage or PLVs. Here, as part of the ICTV Virophage Study Group, we leverage a large set of genomes gathered from published datasets as well as newly generated protist genomes to propose delineation criteria and classification methods at multiple taxonomic ranks for virophages 'sensu stricto', i.e., genomes related to the prototype isolates Sputnik and mavirus. Based on a combination of comparative genomics and phylogenetic analyses, we show that this group of virophages forms a cohesive taxon that we propose to establish at the class level and suggest a subdivision into four orders and seven families with distinctive ecogenomic features. Finally, to illustrate how the proposed delineation criteria and classification method would be used, we apply these to two recently published datasets, which we show include both virophages and other virophage-related elements. Overall, we see this proposed classification as a necessary first step to provide a robust taxonomic framework in this area of the virosphere, which will need to be expanded in the future to cover other virophage-related viruses such as PLVs.
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Affiliation(s)
- Simon Roux
- DOE Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Matthias G. Fischer
- Max Planck Institute for Medical Research, Department of Biomolecular Mechanisms, 69120 Heidelberg, Germany
| | - Thomas Hackl
- Groningen Institute of Evolutionary Life Sciences, University of Groningen, 9700 AB Groningen, The Netherlands
| | - Laura A. Katz
- Department of Biological Sciences, Smith College, Northampton, MA 01063, USA
| | - Frederik Schulz
- DOE Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Natalya Yutin
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, MD 20894, USA
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28
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Dai Z, Wang H, Wu H, Zhang Q, Ji L, Wang X, Shen Q, Yang S, Ma X, Shan T, Zhang W. Parvovirus dark matter in the cloaca of wild birds. Gigascience 2022; 12:giad001. [PMID: 36734170 PMCID: PMC9896142 DOI: 10.1093/gigascience/giad001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2022] [Revised: 11/28/2022] [Accepted: 01/03/2023] [Indexed: 02/04/2023] Open
Abstract
With the development of viral metagenomics and next-generation sequencing technology, more and more novel parvoviruses have been identified in recent years, including even entirely new lineages. The Parvoviridae family includes a different group of viruses that can infect a wide variety of animals. In this study, systematic analysis was performed to identify the "dark matter" (datasets that cannot be easily attributed to known viruses) of parvoviruses and to explore their genetic diversity from wild birds' cloacal swab samples. We have tentatively defined this parvovirus "dark matter" as a highly divergent lineage in the Parvoviridae family. All parvoviruses showed several characteristics, including 2 major protein-coding genes and similar genome lengths. Moreover, we observed that the novel parvo-like viruses share similar genome organizations to most viruses in Parvoviridae but could not clustered with the established subfamilies in phylogenetic analysis. We also found some new members associated with the Bidnaviridae family, which may be derived from parvovirus. This suggests that systematic analysis of domestic and wild animal samples is necessary to explore the genetic diversity of parvoviruses and to mine for more of this potential dark matter.
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Affiliation(s)
- Ziyuan Dai
- Department of Laboratory Medicine, School of Medicine, Jiangsu University, Zhenjiang, Jiangsu 212013, China
- Department of Clinical Laboratory, The Sixth Affiliated Hospital of Nantong University, Yancheng Third People's Hospital, Yancheng, Jiangsu 224001, China
| | - Haoning Wang
- School of Geography and Tourism, Harbin University, Harbin, Heilongjiang 150076, China
| | - Haisheng Wu
- Department of Laboratory Medicine, School of Medicine, Jiangsu University, Zhenjiang, Jiangsu 212013, China
- Qinghai Institute of Endemic Disease Prevention and Control, Xining, Qinghai 810099, China
| | - Qing Zhang
- Qinghai Institute of Endemic Disease Prevention and Control, Xining, Qinghai 810099, China
| | - Likai Ji
- Department of Laboratory Medicine, School of Medicine, Jiangsu University, Zhenjiang, Jiangsu 212013, China
| | - Xiaochun Wang
- Department of Laboratory Medicine, School of Medicine, Jiangsu University, Zhenjiang, Jiangsu 212013, China
| | - Quan Shen
- Department of Laboratory Medicine, School of Medicine, Jiangsu University, Zhenjiang, Jiangsu 212013, China
| | - Shixing Yang
- Department of Laboratory Medicine, School of Medicine, Jiangsu University, Zhenjiang, Jiangsu 212013, China
| | - Xiao Ma
- Qinghai Institute of Endemic Disease Prevention and Control, Xining, Qinghai 810099, China
| | - Tongling Shan
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 810099, China
| | - Wen Zhang
- Department of Laboratory Medicine, School of Medicine, Jiangsu University, Zhenjiang, Jiangsu 212013, China
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29
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Evolutionary Analysis of Placental Orthologues Reveals Two Ancient DNA Virus Integrations. J Virol 2022; 96:e0093322. [DOI: 10.1128/jvi.00933-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The genomes of vertebrates preserve a large diversity of endogenous viral elements (remnants of ancient viruses that accumulate in host genomes over evolutionary time). Although retroviruses account for the vast majority of these elements, diverse DNA viruses have also been found and novel lineages are being described.
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30
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Past and present giant viruses diversity explored through permafrost metagenomics. Nat Commun 2022; 13:5853. [PMID: 36207343 PMCID: PMC9546926 DOI: 10.1038/s41467-022-33633-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2022] [Accepted: 09/27/2022] [Indexed: 11/17/2022] Open
Abstract
Giant viruses are abundant in aquatic environments and ecologically important through the metabolic reprogramming of their hosts. Less is known about giant viruses from soil even though two of them, belonging to two different viral families, were reactivated from 30,000-y-old permafrost samples. This suggests an untapped diversity of Nucleocytoviricota in this environment. Through permafrost metagenomics we reveal a unique diversity pattern and a high heterogeneity in the abundance of giant viruses, representing up to 12% of the sum of sequence coverage in one sample. Pithoviridae and Orpheoviridae-like viruses were the most important contributors. A complete 1.6 Mb Pithoviridae-like circular genome was also assembled from a 42,000-y-old sample. The annotation of the permafrost viral sequences revealed a patchwork of predicted functions amidst a larger reservoir of genes of unknown functions. Finally, the phylogenetic reconstructions not only revealed gene transfers between cells and viruses, but also between viruses from different families. Although giant viruses are abundant in aquatic environments, less is known about giant viruses in soil. Here, the authors use permafrost metagenomics to reveal giant virus diversity and heterogeneity, as well as gene transfers between viruses from different families.
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31
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Ilyina TS. Adaptive Immunity Systems of Bacteria: Association with Self-Synthesizing Transposons, Polyfunctionality. MOLECULAR GENETICS, MICROBIOLOGY AND VIROLOGY 2022. [DOI: 10.3103/s0891416822030065] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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32
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Xu Y, Wang H, Sahu SK, Li L, Liang H, Günther G, Wong GKS, Melkonian B, Melkonian M, Liu H, Wang S. Chromosome-level genome of Pedinomonas minor (Chlorophyta) unveils adaptations to abiotic stress in a rapidly fluctuating environment. THE NEW PHYTOLOGIST 2022; 235:1409-1425. [PMID: 35560066 DOI: 10.1111/nph.18220] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2022] [Accepted: 05/04/2022] [Indexed: 06/15/2023]
Abstract
The Pedinophyceae (Viridiplantae) comprise a class of small uniflagellate algae with a pivotal position in the phylogeny of the Chlorophyta as the sister group of the 'core chlorophytes'. We present a chromosome-level genome assembly of the freshwater type species of the class, Pedinomonas minor. We sequenced the genome using Pacbio, Illumina and Hi-C technologies, performed comparative analyses of genome and gene family evolution, and analyzed the transcriptome under various abiotic stresses. Although the genome is relatively small (55 Mb), it shares many traits with core chlorophytes including number of introns and protein-coding genes, messenger RNA (mRNA) lengths, and abundance of transposable elements. Pedinomonas minor is only bounded by the plasma membrane, thriving in temporary habitats that frequently dry out. Gene family innovations and expansions and transcriptomic responses to abiotic stresses have shed light on adaptations of P. minor to its fluctuating environment. Horizontal gene transfers from bacteria and fungi have possibly contributed to the evolution of some of these traits. We identified a putative endogenization site of a nucleocytoplasmic large DNA virus and hypothesized that endogenous viral elements donated foreign genes to the host genome, their spread enhanced by transposable elements, located at gene boundaries in several of the expanded gene families.
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Affiliation(s)
- Yan Xu
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, 10049, China
- State Key Laboratory of Agricultural Genomics, BGI-Shenzhen, Shenzhen, 518083, China
| | - Hongli Wang
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, 10049, China
- State Key Laboratory of Agricultural Genomics, BGI-Shenzhen, Shenzhen, 518083, China
| | - Sunil Kumar Sahu
- State Key Laboratory of Agricultural Genomics, BGI-Shenzhen, Shenzhen, 518083, China
| | - Linzhou Li
- State Key Laboratory of Agricultural Genomics, BGI-Shenzhen, Shenzhen, 518083, China
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Kgs. Lyngby, 2800, Denmark
| | - Hongping Liang
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, 10049, China
- State Key Laboratory of Agricultural Genomics, BGI-Shenzhen, Shenzhen, 518083, China
| | - Gerd Günther
- Private Laboratory, Knittkuhler Str. 61, Düsseldorf, 40629, Germany
| | - Gane Ka-Shu Wong
- Department of Biological Sciences, University of Alberta, Edmonton, AB, T6G 2E9, Canada
- Department of Medicine, University of Alberta, Edmonton, AB, T6G 2E9, Canada
| | - Barbara Melkonian
- Department of Plant Microbe Interactions, Max Planck Institute for Plant Breeding Research, Cologne, 50829, Germany
| | - Michael Melkonian
- Department of Plant Microbe Interactions, Max Planck Institute for Plant Breeding Research, Cologne, 50829, Germany
| | - Huan Liu
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, 10049, China
- State Key Laboratory of Agricultural Genomics, BGI-Shenzhen, Shenzhen, 518083, China
| | - Sibo Wang
- State Key Laboratory of Agricultural Genomics, BGI-Shenzhen, Shenzhen, 518083, China
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33
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Chase EE, Desnues C, Blanc G. Integrated Viral Elements Suggest the Dual Lifestyle of Tetraselmis Spp. Polinton-Like Viruses. Virus Evol 2022; 8:veac068. [PMID: 35949392 PMCID: PMC9356565 DOI: 10.1093/ve/veac068] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2022] [Revised: 06/30/2022] [Accepted: 07/21/2022] [Indexed: 12/03/2022] Open
Abstract
In this study, we aimed at exploring horizontal gene transfer between viruses and Chlorodendraceae green algae (Chlorophyta) using available genomic and transcriptomic sequences for twenty algal strains. We identified a significant number of genes sharing a higher sequence similarity with viral homologues, thus signalling their possible involvement in horizontal gene transfers with viruses. Further characterization showed that many of these genes were clustered in DNA regions of several tens to hundreds of kilobases in size, originally belonging to viruses related to known Tetraselmis spp. viruses (TetV and TsV). In contrast, the remaining candidate HGT genes were randomly dispersed in the algal genomes, were more frequently transcribed, and belonged to large multigene families. The presence of homologues in Viridiplantae suggested that the latter were more likely of algal rather than viral origin. We found a remarkable diversity in polinton-like virus (PLV) elements inserted in Tetraselmis genomes, all of which were most similar to the Tetraselmis striata virus (TsV). The genes of PLV elements are transcriptionally inactive with the notable exception of the homologue of the TVSG_00024 gene of TsV whose function is unknown. We suggest that this gene may be involved in a sentinel process to trigger virus reactivation and excision in response to an environmental stimulus. Altogether, these results provide evidence that TsV-related viruses have a dual lifestyle, alternating between a free viral phase (i.e. virion) and a phase integrated into host genomes.
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Affiliation(s)
- Emily E Chase
- Microbiologie Environnementale Biotechnologie, Institut Méditerranéen d’Océanologie, Campus de Luminy , 163 Avenue de Luminy, 13009 Marseille, France
- Institut hospitalo-universitaire (IHU) Méditerranée infection , 19-21 Boulevard Jean Moulin, 13005 Marseille, France
| | - Christelle Desnues
- Microbiologie Environnementale Biotechnologie, Institut Méditerranéen d’Océanologie, Campus de Luminy , 163 Avenue de Luminy, 13009 Marseille, France
- Institut hospitalo-universitaire (IHU) Méditerranée infection , 19-21 Boulevard Jean Moulin, 13005 Marseille, France
| | - Guillaume Blanc
- Microbiologie Environnementale Biotechnologie, Institut Méditerranéen d’Océanologie, Campus de Luminy , 163 Avenue de Luminy, 13009 Marseille, France
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34
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Nguyen A, Wang W, Chong E, Chatla K, Bachtrog D. Transposable element accumulation drives size differences among polymorphic Y Chromosomes in Drosophila. Genome Res 2022; 32:1074-1088. [PMID: 35501131 DOI: 10.1101/gr.275996.121] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2021] [Accepted: 04/15/2022] [Indexed: 11/24/2022]
Abstract
Y Chromosomes of many species are gene poor and show low levels of nucleotide variation, yet often display high amounts of structural diversity. Dobzhansky cataloged several morphologically distinct Y Chromosomes in Drosophila pseudoobscura that differ in size and shape, but the molecular causes of their dramatic size differences are unclear. Here we use cytogenetics and long-read sequencing to study the sequence content of polymorphic Y Chromosomes in D. pseudoobscura We show that Y Chromosomes differ almost 2-fold in size, ranging from 30 to 60 Mb. Most of this size difference is caused by a handful of active transposable elements (TEs) that have recently expanded on the largest Y Chromosome, with different elements being responsible for Y expansion on differently sized D. pseudoobscura Y's. We show that Y Chromosomes differ in their heterochromatin enrichment, expression of Y-enriched TEs, and also influence expression of dozens of autosomal and X-linked genes. The same helitron element that showed the most drastic amplification on the largest Y in D. pseudoobscura independently amplified on a polymorphic large Y Chromosome in D. affinis, suggesting that some TEs are inherently more prone to become deregulated on Y Chromosomes.
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35
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Kejnovsky E, Jedlicka P. Nucleic acids movement and its relation to genome dynamics of repetitive DNA: Is cellular and intercellular movement of DNA and RNA molecules related to the evolutionary dynamic genome components?: Is cellular and intercellular movement of DNA and RNA molecules related to the evolutionary dynamic genome components? Bioessays 2022; 44:e2100242. [PMID: 35112737 DOI: 10.1002/bies.202100242] [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: 10/14/2021] [Revised: 01/13/2022] [Accepted: 01/17/2022] [Indexed: 11/07/2022]
Abstract
There is growing evidence of evolutionary genome plasticity. The evolution of repetitive DNA elements, the major components of most eukaryotic genomes, involves the amplification of various classes of mobile genetic elements, the expansion of satellite DNA, the transfer of fragments or entire organellar genomes and may have connections with viruses. In addition to various repetitive DNA elements, a plethora of large and small RNAs migrate within and between cells during individual development as well as during evolution and contribute to changes of genome structure and function. Such migration of DNA and RNA molecules often results in horizontal gene transfer, thus shaping the whole genomic network of interconnected species. Here, we propose that a high evolutionary dynamism of repetitive genome components is often related to the migration/movement of DNA or RNA molecules. We speculate that the cytoplasm is probably an ideal compartment for such evolutionary experiments.
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Affiliation(s)
- Eduard Kejnovsky
- Department of Plant Developmental Genetics, Institute of Biophysics, Academy of Sciences of the Czech Republic, Brno, Czech Republic
| | - Pavel Jedlicka
- Department of Plant Developmental Genetics, Institute of Biophysics, Academy of Sciences of the Czech Republic, Brno, Czech Republic
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36
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Timmons CM, Shazib SUA, Katz LA. Epigenetic influences of mobile genetic elements on ciliate genome architecture and evolution. J Eukaryot Microbiol 2022; 69:e12891. [PMID: 35100457 DOI: 10.1111/jeu.12891] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2021] [Revised: 01/20/2022] [Accepted: 01/22/2022] [Indexed: 11/27/2022]
Abstract
Mobile genetic elements (MGEs) are transient genetic material that can move either within a single organism's genome or between individuals or species. While historically considered 'junk' DNA (i.e. deleterious or at best neutral), more recent studies reveal the adaptive advantages MGEs provide in lineages across the tree of life. Ciliates, a group of single-celled microbial eukaryotes characterized by nuclear dimorphism, exemplify how epigenetic influences from MGEs shape genome architecture and patterns of molecular evolution. Ciliate nuclear dimorphism may have evolved as a response to transposon invasion and ciliates have since co-opted transposons to carry out programmed DNA deletion. Another example of the effect of MGEs is in providing mechanisms for lateral gene transfer from bacteria, which introduces genetic diversity and, in several cases, drives ecological specialization in ciliates. As a third example, the integration of viral DNA, likely through transduction, provides new genetic material and can change the way host cells defend themselves against other viral pathogens. We argue that the acquisition of MGEs through non-Mendelian patterns of inheritance, coupled with their effects on ciliate genome architecture and expression and persistence throughout evolutionary history, exemplify how the transmission of mobile elements should be considered a mechanism of transgenerational epigenetic inheritance.
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Affiliation(s)
- Caitlin M Timmons
- Department of Biological Sciences, Smith College, Northampton, Massachusetts, 01063, USA
| | - Shahed U A Shazib
- Department of Biological Sciences, Smith College, Northampton, Massachusetts, 01063, USA
| | - Laura A Katz
- Department of Biological Sciences, Smith College, Northampton, Massachusetts, 01063, USA
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Viral dUTPases: Modulators of Innate Immunity. Biomolecules 2022; 12:biom12020227. [PMID: 35204728 PMCID: PMC8961515 DOI: 10.3390/biom12020227] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2021] [Revised: 01/24/2022] [Accepted: 01/26/2022] [Indexed: 11/17/2022] Open
Abstract
Most free-living organisms encode for a deoxyuridine triphosphate nucleotidohydrolase (dUTPase; EC 3.6.1.23). dUTPases represent a family of metalloenzymes that catalyze the hydrolysis of dUTP to dUMP and pyrophosphate, preventing dUTP from being incorporated into DNA by DNA polymerases, maintaining a low dUTP/dTTP pool ratio and providing a necessary precursor for dTTP biosynthesis. Thus, dUTPases are involved in maintaining genomic integrity by preventing the uracilation of DNA. Many DNA-containing viruses, which infect mammals also encode for a dUTPase. This review will summarize studies demonstrating that, in addition to their classical enzymatic activity, some dUTPases possess novel functions that modulate the host innate immune response.
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38
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Cellular homologs of the double jelly-roll major capsid proteins clarify the origins of an ancient virus kingdom. Proc Natl Acad Sci U S A 2022; 119:2120620119. [PMID: 35078938 PMCID: PMC8812541 DOI: 10.1073/pnas.2120620119] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/18/2021] [Indexed: 12/26/2022] Open
Abstract
Viruses are the most abundant biological entities on Earth and ubiquitous parasites of cellular life forms. The general scenario for the origin of viruses involves evolution from nonviral replicators, such as plasmids and transposons, via recruitment of host proteins for virion formation. One of the most common virion core components, the double jelly-roll major capsid protein of a broad variety of viruses with double-stranded DNA genomes, so far has been thought to represent a virus innovation. However, we present evidence, obtained by protein structure comparison, that this type of virus capsid protein also evolved from a cellular ancestor, a distinct family of carbohydrate-active enzymes. These findings reinforce the chimeric scenario of virus origin. Viruses are a distinct type of replicators that encode structural proteins encasing virus genomes in virions. For some of the widespread virus capsid proteins and other major components of virions, likely ancestors encoded by cellular life forms are identifiable. In particular, one of the most common capsid proteins, with the single jelly-roll (SJR) fold, appears to have evolved from a particular family of cellular carbohydrate-binding proteins. However, the double jelly-roll major capsid protein (DJR-MCP), the hallmark of the enormously diverse viruses of the kingdom Bamfordvirae within the realm Varidnaviria, which includes bacterial and archaeal icosahedral viruses as well as eukaryotic giant viruses, has been perceived as a virus innovation that evolved by duplication and fusion of the SJR capsid proteins. Here we employ protein structure comparison to show that the DJR fold is represented in several widespread families of cellular proteins, including several groups of carbohydrate-active enzymes. We show that DJR-MCPs share a common ancestry with a distinct family of bacterial DJR proteins (DUF2961) involved in carbohydrate metabolism. Based on this finding, we propose a scenario in which bamfordviruses evolved from nonviral replicators, in particular plasmids, by recruiting a host protein for capsid formation. This sequence of events appears to be the general route of virus origin. The results of this work indicate that virus kingdoms Bamfordvirae, with the DJR-MCPs, and Helvetiavirae that possess two SJR-MCPs, have distinct origins, suggesting a reappraisal of the realm Varidnaviria.
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39
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Koonin EV, Dolja VV, Krupovic M, Kuhn JH. Viruses Defined by the Position of the Virosphere within the Replicator Space. Microbiol Mol Biol Rev 2021; 85:e0019320. [PMID: 34468181 PMCID: PMC8483706 DOI: 10.1128/mmbr.00193-20] [Citation(s) in RCA: 40] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Originally, viruses were defined as miniscule infectious agents that passed through filters that retain even the smallest cells. Subsequently, viruses were considered obligate intracellular parasites whose reproduction depends on their cellular hosts for energy supply and molecular building blocks. However, these features are insufficient to unambiguously define viruses as they are broadly understood today. We outline possible approaches to define viruses and explore the boundaries of the virosphere within the virtual space of replicators and the relationships between viruses and other types of replicators. Regardless of how, exactly, viruses are defined, viruses clearly have evolved on many occasions from nonviral replicators, such as plasmids, by recruiting host proteins to become virion components. Conversely, other types of replicators have repeatedly evolved from viruses. Thus, the virosphere is a dynamic entity with extensive evolutionary traffic across its boundaries. We argue that the virosphere proper, here termed orthovirosphere, consists of a distinct variety of replicators that encode structural proteins encasing the replicators' genomes, thereby providing protection and facilitating transmission among hosts. Numerous and diverse replicators, such as virus-derived but capsidless RNA and DNA elements, or defective viruses occupy the zone surrounding the orthovirosphere in the virtual replicator space. We define this zone as the perivirosphere. Although intense debates on the nature of certain replicators that adorn the internal and external boundaries of the virosphere will likely continue, we present an operational definition of virus that recently has been accepted by the International Committee on Taxonomy of Viruses.
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Affiliation(s)
- Eugene V. Koonin
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, Maryland, USA
| | - Valerian V. Dolja
- Department of Botany and Plant Pathology, Oregon State University, Corvallis, Oregon, USA
| | - Mart Krupovic
- Archaeal Virology Unit, Institut Pasteur, Paris, France
| | - Jens H. Kuhn
- Integrated Research Facility at Fort Detrick, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Frederick, Maryland, USA
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40
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Unraveling Protein Interactions between the Temperate Virus Bam35 and Its Bacillus Host Using an Integrative Yeast Two Hybrid-High Throughput Sequencing Approach. Int J Mol Sci 2021; 22:ijms222011105. [PMID: 34681765 PMCID: PMC8539640 DOI: 10.3390/ijms222011105] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2021] [Revised: 10/08/2021] [Accepted: 10/10/2021] [Indexed: 11/20/2022] Open
Abstract
Bacillus virus Bam35 is the model Betatectivirus and member of the family Tectiviridae, which is composed of tailless, icosahedral, and membrane-containing bacteriophages. Interest in these viruses has greatly increased in recent years as they are thought to be an evolutionary link between diverse groups of prokaryotic and eukaryotic viruses. Additionally, betatectiviruses infect bacteria of the Bacillus cereus group, which are known for their applications in industry and notorious since it contains many pathogens. Here, we present the first protein–protein interactions (PPIs) network for a tectivirus–host system by studying the Bam35–Bacillus thuringiensis model using a novel approach that integrates the traditional yeast two-hybrid system and high-throughput sequencing (Y2H-HTS). We generated and thoroughly analyzed a genomic library of Bam35′s host B. thuringiensis HER1410 and screened interactions with all the viral proteins using different combinations of bait–prey couples. Initial analysis of the raw data enabled the identification of over 4000 candidate interactions, which were sequentially filtered to produce 182 high-confidence interactions that were defined as part of the core virus–host interactome. Overall, host metabolism proteins and peptidases were particularly enriched within the detected interactions, distinguishing this host–phage system from the other reported host–phage PPIs. Our approach also suggested biological roles for several Bam35 proteins of unknown function, including the membrane structural protein P25, which may be a viral hub with a role in host membrane modification during viral particle morphogenesis. This work resulted in a better understanding of the Bam35–B. thuringiensis interaction at the molecular level and holds great potential for the generalization of the Y2H-HTS approach for other virus–host models.
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41
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Mönttinen HAM, Bicep C, Williams TA, Hirt RP. The genomes of nucleocytoplasmic large DNA viruses: viral evolution writ large. Microb Genom 2021; 7. [PMID: 34542398 PMCID: PMC8715426 DOI: 10.1099/mgen.0.000649] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
The nucleocytoplasmic large DNA viruses (NCLDVs) are a diverse group that currently contain the largest known virions and genomes, also called giant viruses. The first giant virus was isolated and described nearly 20 years ago. Their genome sizes were larger than for any other known virus at the time and it contained a number of genes that had not been previously described in any virus. The origin and evolution of these unusually complex viruses has been puzzling, and various mechanisms have been put forward to explain how some NCLDVs could have reached genome sizes and coding capacity overlapping with those of cellular microbes. Here we critically discuss the evidence and arguments on this topic. We have also updated and systematically reanalysed protein families of the NCLDVs to further study their origin and evolution. Our analyses further highlight the small number of widely shared genes and extreme genomic plasticity among NCLDVs that are shaped via combinations of gene duplications, deletions, lateral gene transfers and de novo creation of protein-coding genes. The dramatic expansions of the genome size and protein-coding gene capacity characteristic of some NCLDVs is now increasingly understood to be driven by environmental factors rather than reflecting relationships to an ancient common ancestor among a hypothetical cellular lineage. Thus, the evolution of NCLDVs is writ large viral, and their origin, like all other viral lineages, remains unknown.
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Affiliation(s)
- Heli A M Mönttinen
- Newcastle University Biosciences Institute, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne, NE2 4HH, UK.,Present address: Institute of Biotechnology, Helsinki Institute of Life Sciences (HiLIFE), University of Helsinki, Viikki Biocenter 2, Helsinki 00014, Finland
| | - Cedric Bicep
- Newcastle University Biosciences Institute, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne, NE2 4HH, UK.,Present address: Université Clermont Auvergne, CNRS, LMGE, F-63000 Clermont Ferrand, France
| | - Tom A Williams
- Newcastle University Biosciences Institute, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne, NE2 4HH, UK.,School of Biological Sciences, University of Bristol, 24 Tyndall Ave., Bristol, BS8 1TH, UK
| | - Robert P Hirt
- Newcastle University Biosciences Institute, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne, NE2 4HH, UK
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42
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Barreat JGN, Katzourakis A. Paleovirology of the DNA viruses of eukaryotes. Trends Microbiol 2021; 30:281-292. [PMID: 34483047 DOI: 10.1016/j.tim.2021.07.004] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2021] [Revised: 07/20/2021] [Accepted: 07/22/2021] [Indexed: 12/17/2022]
Abstract
Paleovirology is the study of ancient viruses and how they have coevolved with their hosts. An increasingly detailed understanding of the diversity, origins, and evolution of the DNA viruses of eukaryotes has been obtained through the lens of paleovirology in recent years. Members of multiple viral families have been found integrated in the genomes of eukaryotes, providing a rich fossil record to study. These elements have extended our knowledge of exogenous viral diversity, host ranges, and the timing of viral evolution, and are revealing the existence of entire new families of eukaryotic integrating dsDNA viruses and transposons. Future work in paleovirology will continue to provide insights into antiviral immunity, viral diversity, and potential applications, and reveal other secrets of the viral world.
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Affiliation(s)
| | - Aris Katzourakis
- Department of Zoology, University of Oxford, Oxford, OX1 3SY, UK.
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43
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Nelson DR, Hazzouri KM, Lauersen KJ, Jaiswal A, Chaiboonchoe A, Mystikou A, Fu W, Daakour S, Dohai B, Alzahmi A, Nobles D, Hurd M, Sexton J, Preston MJ, Blanchette J, Lomas MW, Amiri KMA, Salehi-Ashtiani K. Large-scale genome sequencing reveals the driving forces of viruses in microalgal evolution. Cell Host Microbe 2021; 29:250-266.e8. [PMID: 33434515 DOI: 10.1016/j.chom.2020.12.005] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2020] [Revised: 10/08/2020] [Accepted: 11/18/2020] [Indexed: 01/08/2023]
Abstract
Being integral primary producers in diverse ecosystems, microalgal genomes could be mined for ecological insights, but representative genome sequences are lacking for many phyla. We cultured and sequenced 107 microalgae species from 11 different phyla indigenous to varied geographies and climates. This collection was used to resolve genomic differences between saltwater and freshwater microalgae. Freshwater species showed domain-centric ontology enrichment for nuclear and nuclear membrane functions, while saltwater species were enriched in organellar and cellular membrane functions. Further, marine species contained significantly more viral families in their genomes (p = 8e-4). Sequences from Chlorovirus, Coccolithovirus, Pandoravirus, Marseillevirus, Tupanvirus, and other viruses were found integrated into the genomes of algal from marine environments. These viral-origin sequences were found to be expressed and code for a wide variety of functions. Together, this study comprehensively defines the expanse of protein-coding and viral elements in microalgal genomes and posits a unified adaptive strategy for algal halotolerance.
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Affiliation(s)
- David R Nelson
- Center for Genomics and Systems Biology, New York University Abu Dhabi, Abu Dhabi, UAE.
| | - Khaled M Hazzouri
- Khalifa Center for Genetic Engineering and Biotechnology (KCGEB), UAE University, Al Ain, Abu Dhabi, UAE; Biology Department, College of Science, UAE University, Al Ain, Abu Dhabi, UAE
| | - Kyle J Lauersen
- Biological and Environmental Sciences and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal, Kingdom of Saudi Arabia
| | - Ashish Jaiswal
- Division of Science and Math, New York University Abu Dhabi, Abu Dhabi, UAE
| | | | - Alexandra Mystikou
- Center for Genomics and Systems Biology, New York University Abu Dhabi, Abu Dhabi, UAE
| | - Weiqi Fu
- Division of Science and Math, New York University Abu Dhabi, Abu Dhabi, UAE
| | - Sarah Daakour
- Center for Genomics and Systems Biology, New York University Abu Dhabi, Abu Dhabi, UAE
| | - Bushra Dohai
- Division of Science and Math, New York University Abu Dhabi, Abu Dhabi, UAE
| | - Amnah Alzahmi
- Center for Genomics and Systems Biology, New York University Abu Dhabi, Abu Dhabi, UAE
| | - David Nobles
- UTEX Culture Collection of Algae at the University of Texas at Austin, Austin, TX, USA
| | - Mark Hurd
- National Center for Marine Algae and Microbiota, East Boothbay, ME, USA
| | - Julie Sexton
- National Center for Marine Algae and Microbiota, East Boothbay, ME, USA
| | - Michael J Preston
- National Center for Marine Algae and Microbiota, East Boothbay, ME, USA
| | - Joan Blanchette
- National Center for Marine Algae and Microbiota, East Boothbay, ME, USA
| | - Michael W Lomas
- National Center for Marine Algae and Microbiota, East Boothbay, ME, USA
| | - Khaled M A Amiri
- Khalifa Center for Genetic Engineering and Biotechnology (KCGEB), UAE University, Al Ain, Abu Dhabi, UAE; Biology Department, College of Science, UAE University, Al Ain, Abu Dhabi, UAE
| | - Kourosh Salehi-Ashtiani
- Center for Genomics and Systems Biology, New York University Abu Dhabi, Abu Dhabi, UAE; Division of Science and Math, New York University Abu Dhabi, Abu Dhabi, UAE.
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44
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Woo AC, Gaia M, Guglielmini J, Da Cunha V, Forterre P. Phylogeny of the Varidnaviria Morphogenesis Module: Congruence and Incongruence With the Tree of Life and Viral Taxonomy. Front Microbiol 2021; 12:704052. [PMID: 34349745 PMCID: PMC8328091 DOI: 10.3389/fmicb.2021.704052] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2021] [Accepted: 06/02/2021] [Indexed: 11/13/2022] Open
Abstract
Double-stranded DNA viruses of the realm Varidnaviria (formerly PRD1-adenovirus lineage) are characterized by homologous major capsid proteins (MCPs) containing one (kingdom: Helvetiavirae) or two β-barrel domains (kingdom: Bamfordvirae) known as the jelly roll folds. Most of them also share homologous packaging ATPases (pATPases). Remarkably, Varidnaviria infect hosts from the three domains of life, suggesting that these viruses could be very ancient and share a common ancestor. Here, we analyzed the evolutionary history of Varidnaviria based on single and concatenated phylogenies of their MCPs and pATPases. We excluded Adenoviridae from our analysis as their MCPs and pATPases are too divergent. Sphaerolipoviridae, the only family in the kingdom Helvetiavirae, exhibit a complex history: their MCPs are very divergent from those of other Varidnaviria, as expected, but their pATPases groups them with Bamfordvirae. In single and concatenated trees, Bamfordvirae infecting archaea were grouped with those infecting bacteria, in contradiction with the cellular tree of life, whereas those infecting eukaryotes were organized into three monophyletic groups: the Nucleocytoviricota phylum, formerly known as the Nucleo-Cytoplasmic Large DNA Viruses (NCLDVs), Lavidaviridae (virophages) and Polintoviruses. Although our analysis mostly supports the recent classification proposed by the International Committee on Taxonomy of Viruses (ICTV), it also raises questions, such as the validity of the Adenoviridae and Helvetiavirae ranking. Based on our phylogeny, we discuss current hypotheses on the origin and evolution of Varidnaviria and suggest new ones to reconcile the viral and cellular trees.
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Affiliation(s)
- Anthony C Woo
- Pôle Analyse de Données UMS 2700 2AD, Muséum National d'Histoire Naturelle, Paris, France.,Département de Microbiologie, Institut Pasteur, Paris, France.,Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), Gif-sur-Yvette, France
| | - Morgan Gaia
- Génomique Métabolique, Génoscope, Institut François Jacob, CEA, CNRS, Univ. Évry, Université Paris-Saclay, Évry, France
| | - Julien Guglielmini
- Hub de Bioinformatique et Biostatistique - Département Biologie Computationnelle, Institut Pasteur, Paris, France
| | - Violette Da Cunha
- Département de Microbiologie, Institut Pasteur, Paris, France.,Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), Gif-sur-Yvette, France
| | - Patrick Forterre
- Département de Microbiologie, Institut Pasteur, Paris, France.,Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), Gif-sur-Yvette, France
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45
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Lechuga A, Kazlauskas D, Salas M, Redrejo-Rodríguez M. Unlimited Cooperativity of Betatectivirus SSB, a Novel DNA Binding Protein Related to an Atypical Group of SSBs From Protein-Primed Replicating Bacterial Viruses. Front Microbiol 2021; 12:699140. [PMID: 34267740 PMCID: PMC8276246 DOI: 10.3389/fmicb.2021.699140] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2021] [Accepted: 06/08/2021] [Indexed: 11/20/2022] Open
Abstract
Bam35 and related betatectiviruses are tail-less bacteriophages that prey on members of the Bacillus cereus group. These temperate viruses replicate their linear genome by a protein-primed mechanism. In this work, we have identified and characterized the product of the viral ORF2 as a single-stranded DNA binding protein (hereafter B35SSB). B35SSB binds ssDNA with great preference over dsDNA or RNA in a sequence-independent, highly cooperative manner that results in a non-specific stimulation of DNA replication. We have also identified several aromatic and basic residues, involved in base-stacking and electrostatic interactions, respectively, that are required for effective protein-ssDNA interaction. Although SSBs are essential for DNA replication in all domains of life as well as many viruses, they are very diverse proteins. However, most SSBs share a common structural domain, named OB-fold. Protein-primed viruses could constitute an exception, as no OB-fold DNA binding protein has been reported. Based on databases searches as well as phylogenetic and structural analyses, we showed that B35SSB belongs to a novel and independent group of SSBs. This group contains proteins encoded by protein-primed viral genomes from unrelated viruses, spanning betatectiviruses and Φ29 and close podoviruses, and they share a conserved pattern of secondary structure. Sensitive searches and structural predictions indicate that B35SSB contains a conserved domain resembling a divergent OB-fold, which would constitute the first occurrence of an OB-fold-like domain in a protein-primed genome.
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Affiliation(s)
- Ana Lechuga
- Centro de Biologiìa Molecular Severo Ochoa (CSIC-UAM), Madrid, Spain
| | - Darius Kazlauskas
- Institute of Biotechnology, Life Sciences Center, Vilnius University, Saulėtekio Av. 7, Vilnius, Lithuania
| | - Margarita Salas
- Centro de Biologiìa Molecular Severo Ochoa (CSIC-UAM), Madrid, Spain
| | - Modesto Redrejo-Rodríguez
- Centro de Biologiìa Molecular Severo Ochoa (CSIC-UAM), Madrid, Spain
- Departamento de Bioquímica, Universidad Autónoma de Madrid (UAM), Madrid, Spain
- Instituto de Investigaciones Biomédicas Alberto Sols (CSIC-UAM), Madrid, Spain
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46
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Abstract
Mavericks are virus-like mobile genetic elements found in the genomes of eukaryotes. Although Mavericks encode capsid morphogenesis homologs, their viral particles have not been observed. Here, we provide new evidence supporting the viral nature of Mavericks and the potential existence of virions. To this end, we conducted a phylogenomic analysis of Mavericks in hundreds of vertebrate genomes, discovering 134 elements with an intact coding capacity in 17 host species. We reveal an extensive genomic fossil record in 143 species and date three groups of elements to the Late Cretaceous. Bayesian phylogenetic analysis using genomic fossil orthologs suggests that Mavericks have infected osteichthyans for ∼419 My. They have undergone frequent cross-species transmissions in cyprinid fish and all core genes are subject to strong purifying selection. We conclude that vertebrate Mavericks form an ancient lineage of aquatic dsDNA viruses which are probably still functional in some vertebrate lineages.
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Affiliation(s)
| | - Aris Katzourakis
- Department of Zoology, University of Oxford, Oxford, United Kingdom
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47
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Cagliani R, Mozzi A, Pontremoli C, Sironi M. Evolution and Origin of Human Viruses. Virology 2021. [DOI: 10.1002/9781119818526.ch8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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48
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Collens AB, Katz LA. Opinion: Genetic Conflict With Mobile Elements Drives Eukaryotic Genome Evolution, and Perhaps Also Eukaryogenesis. J Hered 2021; 112:140-144. [PMID: 33538295 PMCID: PMC7953837 DOI: 10.1093/jhered/esaa060] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2020] [Accepted: 12/17/2020] [Indexed: 12/13/2022] Open
Abstract
Through analyses of diverse microeukaryotes, we have previously argued that eukaryotic genomes are dynamic systems that rely on epigenetic mechanisms to distinguish germline (i.e., DNA to be inherited) from soma (i.e., DNA that undergoes polyploidization, genome rearrangement, etc.), even in the context of a single nucleus. Here, we extend these arguments by including two well-documented observations: (1) eukaryotic genomes interact frequently with mobile genetic elements (MGEs) like viruses and transposable elements (TEs), creating genetic conflict, and (2) epigenetic mechanisms regulate MGEs. Synthesis of these ideas leads to the hypothesis that genetic conflict with MGEs contributed to the evolution of a dynamic eukaryotic genome in the last eukaryotic common ancestor (LECA), and may have contributed to eukaryogenesis (i.e., may have been a driver in the evolution of FECA, the first eukaryotic common ancestor). Sex (i.e., meiosis) may have evolved within the context of the development of germline-soma distinctions in LECA, as this process resets the germline genome by regulating/eliminating somatic (i.e., polyploid, rearranged) genetic material. Our synthesis of these ideas expands on hypotheses of the origin of eukaryotes by integrating the roles of MGEs and epigenetics.
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Affiliation(s)
- Adena B Collens
- Department of Biological Sciences, Smith College, Northampton, MA
| | - Laura A Katz
- Department of Biological Sciences, Smith College, Northampton, MA
- Program in Organismic and Evolutionary Biology, University of Massachusetts, Amherst, MA
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49
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Bellas CM, Sommaruga R. Polinton-like viruses are abundant in aquatic ecosystems. MICROBIOME 2021; 9:13. [PMID: 33436089 PMCID: PMC7805220 DOI: 10.1186/s40168-020-00956-0] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2020] [Accepted: 12/06/2020] [Indexed: 05/28/2023]
Abstract
BACKGROUND Polintons are large mobile genetic elements found in the genomes of eukaryotic organisms that are considered the ancient ancestors of most eukaryotic dsDNA viruses. Originally considered as transposons, they have been found to encode virus capsid genes, suggesting they may actually be integrated viruses; however, an extracellular form has yet to be detected. Recently, circa 25 Polinton-like viruses have been discovered in environmental metagenomes and algal genomes, which shared distantly related genes to both Polintons and virophages (Lavidaviridae). These entities could be the first members of a major class of ancient eukaryotic viruses; however, owing to the lack of available genomes for analysis, information on their global diversity, evolutionary relationships, eukaryotic hosts, and status as free virus particles is limited. RESULTS Here, we analysed the metaviromes of an alpine lake to show that Polinton-like virus genome sequences are abundant in the water column. We identify major capsid protein genes belonging to 82 new Polinton-like viruses and use these to interrogate publicly available metagenomic datasets, identifying 543 genomes and a further 16 integrated into eukaryotic genomes. Using an analysis of shared gene content and major capsid protein phylogeny, we define large groups of Polinton-like viruses and link them to diverse eukaryotic hosts, including a new group of viruses, which possess all the core genes of virophages and infect oomycetes and Chrysophyceae. CONCLUSIONS Our study increased the number of known Polinton-like viruses by 25-fold, identifying five major new groups of eukaryotic viruses, which until now have been hidden in metagenomic datasets. The large enrichment (> 100-fold) of Polinton-like virus sequences in the virus-sized fraction of this alpine lake and the fact that their viral major capsid proteins are found in eukaryotic host transcriptomes support the hypothesis that Polintons in unicellular eukaryotes are viruses. In summary, our data reveals a diverse assemblage of globally distributed viruses, associated with a wide range of unicellular eukaryotic hosts. We anticipate that the methods we have developed for Polinton-like virus detection and the database of over 20,000 genes we present will allow for continued discovery and analysis of these new viral groups. Video abstract.
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Affiliation(s)
- Christopher M. Bellas
- Department of Ecology, University of Innsbruck, Technikerstrasse 25, A-6020 Innsbruck, Austria
| | - Ruben Sommaruga
- Department of Ecology, University of Innsbruck, Technikerstrasse 25, A-6020 Innsbruck, Austria
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Etchegaray E, Naville M, Volff JN, Haftek-Terreau Z. Transposable element-derived sequences in vertebrate development. Mob DNA 2021; 12:1. [PMID: 33407840 PMCID: PMC7786948 DOI: 10.1186/s13100-020-00229-5] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Accepted: 12/15/2020] [Indexed: 12/14/2022] Open
Abstract
Transposable elements (TEs) are major components of all vertebrate genomes that can cause deleterious insertions and genomic instability. However, depending on the specific genomic context of their insertion site, TE sequences can sometimes get positively selected, leading to what are called "exaptation" events. TE sequence exaptation constitutes an important source of novelties for gene, genome and organism evolution, giving rise to new regulatory sequences, protein-coding exons/genes and non-coding RNAs, which can play various roles beneficial to the host. In this review, we focus on the development of vertebrates, which present many derived traits such as bones, adaptive immunity and a complex brain. We illustrate how TE-derived sequences have given rise to developmental innovations in vertebrates and how they thereby contributed to the evolutionary success of this lineage.
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Affiliation(s)
- Ema Etchegaray
- Institut de Genomique Fonctionnelle de Lyon, Univ Lyon, CNRS UMR 5242, Ecole Normale Superieure de Lyon, Universite Claude Bernard Lyon 1, 46 allee d'Italie, F-69364, Lyon, France.
| | - Magali Naville
- Institut de Genomique Fonctionnelle de Lyon, Univ Lyon, CNRS UMR 5242, Ecole Normale Superieure de Lyon, Universite Claude Bernard Lyon 1, 46 allee d'Italie, F-69364, Lyon, France
| | - Jean-Nicolas Volff
- Institut de Genomique Fonctionnelle de Lyon, Univ Lyon, CNRS UMR 5242, Ecole Normale Superieure de Lyon, Universite Claude Bernard Lyon 1, 46 allee d'Italie, F-69364, Lyon, France
| | - Zofia Haftek-Terreau
- Institut de Genomique Fonctionnelle de Lyon, Univ Lyon, CNRS UMR 5242, Ecole Normale Superieure de Lyon, Universite Claude Bernard Lyon 1, 46 allee d'Italie, F-69364, Lyon, France
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