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Sadowska-Bartosz I, Bartosz G. Antioxidant Defense in the Toughest Animals on the Earth: Its Contribution to the Extreme Resistance of Tardigrades. Int J Mol Sci 2024; 25:8393. [PMID: 39125965 PMCID: PMC11313143 DOI: 10.3390/ijms25158393] [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: 06/22/2024] [Revised: 07/23/2024] [Accepted: 07/29/2024] [Indexed: 08/12/2024] Open
Abstract
Tardigrades are unique among animals in their resistance to dehydration, mainly due to anhydrobiosis and tun formation. They are also very resistant to high-energy radiation, low and high temperatures, low and high pressure, and various chemical agents, Interestingly, they are resistant to ionizing radiation both in the hydrated and dehydrated states to a similar extent. They are able to survive in the cosmic space. Apparently, many mechanisms contribute to the resistance of tardigrades to harmful factors, including the presence of trehalose (though not common to all tardigrades), heat shock proteins, late embryogenesis-abundant proteins, tardigrade-unique proteins, DNA repair proteins, proteins directly protecting DNA (Dsup and TDR1), and efficient antioxidant system. Antioxidant enzymes and small-molecular-weight antioxidants are an important element in the tardigrade resistance. The levels and activities of many antioxidant proteins is elevated by anhydrobiosis and UV radiation; one explanation for their induction during dehydration is provided by the theory of "preparation for oxidative stress", which occurs during rehydration. Genes coding for some antioxidant proteins are expanded in tardigrades; some genes (especially those coding for catalases) were hypothesized to be of bacterial origin, acquired by horizontal gene transfer. An interesting antioxidant protein found in tardigrades is the new Mn-dependent peroxidase.
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Affiliation(s)
- Izabela Sadowska-Bartosz
- Laboratory of Analytical Biochemistry, Institute of Food Technology and Nutrition, College of Natural Sciences, University of Rzeszów, 4 Zelwerowicza Street, 35-601 Rzeszow, Poland;
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2
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Robison ZL, Ren Q, Zhang Z. How to Survive without Water: A Short Lesson on the Desiccation Tolerance of Budding Yeast. Int J Mol Sci 2024; 25:7514. [PMID: 39062766 PMCID: PMC11277543 DOI: 10.3390/ijms25147514] [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: 06/21/2024] [Revised: 07/03/2024] [Accepted: 07/08/2024] [Indexed: 07/28/2024] Open
Abstract
Water is essential to all life on earth. It is a major component that makes up living organisms and plays a vital role in multiple biological processes. It provides a medium for chemical and enzymatic reactions in the cell and is a major player in osmoregulation and the maintenance of cell turgidity. Despite this, many organisms, called anhydrobiotes, are capable of surviving under extremely dehydrated conditions. Less is known about how anhydrobiotes adapt and survive under desiccation stress. Studies have shown that morphological and physiological changes occur in anhydrobiotes in response to desiccation stress. Certain disaccharides and proteins, including heat shock proteins, intrinsically disordered proteins, and hydrophilins, play important roles in the desiccation tolerance of anhydrobiotes. In this review, we summarize the recent findings of desiccation tolerance in the budding yeast Saccharomyces cerevisiae. We also propose that the yeast under desiccation could be used as a model to study neurodegenerative disorders.
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Affiliation(s)
| | | | - Zhaojie Zhang
- Department of Zoology and Physiology, University of Wyoming, Laramie, WY 82071, USA; (Z.L.R.); (Q.R.)
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3
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Vuruputoor VS, Starovoitov A, Cai Y, Liu Y, Rahmatpour N, Hedderson TA, Wilding N, Wegrzyn JL, Goffinet B. Crossroads of assembling a moss genome: navigating contaminants and horizontal gene transfer in the moss Physcomitrellopsis africana. G3 (BETHESDA, MD.) 2024; 14:jkae104. [PMID: 38781445 PMCID: PMC11228847 DOI: 10.1093/g3journal/jkae104] [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: 03/18/2024] [Revised: 05/03/2024] [Accepted: 05/09/2024] [Indexed: 05/25/2024]
Abstract
The first chromosome-scale reference genome of the rare narrow-endemic African moss Physcomitrellopsis africana (P. africana) is presented here. Assembled from 73 × Oxford Nanopore Technologies (ONT) long reads and 163 × Beijing Genomics Institute (BGI)-seq short reads, the 414 Mb reference comprises 26 chromosomes and 22,925 protein-coding genes [Benchmarking Universal Single-Copy Ortholog (BUSCO) scores: C:94.8% (D:13.9%)]. This genome holds 2 genes that withstood rigorous filtration of microbial contaminants, have no homolog in other land plants, and are thus interpreted as resulting from 2 unique horizontal gene transfers (HGTs) from microbes. Further, P. africana shares 176 of the 273 published HGT candidates identified in Physcomitrium patens (P. patens), but lacks 98 of these, highlighting that perhaps as many as 91 genes were acquired in P. patens in the last 40 million years following its divergence from its common ancestor with P. africana. These observations suggest rather continuous gene gains via HGT followed by potential losses during the diversification of the Funariaceae. Our findings showcase both dynamic flux in plant HGTs over evolutionarily "short" timescales, alongside enduring impacts of successful integrations, like those still functionally maintained in extant P. africana. Furthermore, this study describes the informatic processes employed to distinguish contaminants from candidate HGT events.
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Affiliation(s)
- Vidya S Vuruputoor
- Department of Ecology and Evolutionary Biology, University of Connecticut, Storrs, CT 06269, USA
| | - Andrew Starovoitov
- Department of Ecology and Evolutionary Biology, University of Connecticut, Storrs, CT 06269, USA
| | - Yuqing Cai
- State Key Laboratory of Agricultural Genomics, BGI-Shenzhen, Shenzhen 518083, China
- Key Laboratory of Southern Subtropical Plant Diversity, Fairy Lake 518004, China
| | - Yang Liu
- State Key Laboratory of Agricultural Genomics, BGI-Shenzhen, Shenzhen 518083, China
- Key Laboratory of Southern Subtropical Plant Diversity, Fairy Lake 518004, China
| | - Nasim Rahmatpour
- Department of Ecology and Evolutionary Biology, University of Connecticut, Storrs, CT 06269, USA
| | - Terry A Hedderson
- Department of Biological Sciences, Bolus Herbarium, University of Cape Town, Private Bag, 7701 Rondebosch, South Africa
| | - Nicholas Wilding
- UMR PVBMT, BP 7151, Université de La Réunion, chemin de l’IRAT, 97410 Saint-Pierre, La Réunion, France
- Missouri Botanical Garden, P.O. Box 299, St. Louis, MO 63166-0299, USA
| | - Jill L Wegrzyn
- Department of Ecology and Evolutionary Biology, University of Connecticut, Storrs, CT 06269, USA
- Institute for Systems Genomics, University of Connecticut, Storrs, CT 06269, USA
| | - Bernard Goffinet
- Department of Ecology and Evolutionary Biology, University of Connecticut, Storrs, CT 06269, USA
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4
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Caetano-Anollés G. Are Viruses Taxonomic Units? A Protein Domain and Loop-Centric Phylogenomic Assessment. Viruses 2024; 16:1061. [PMID: 39066224 PMCID: PMC11281659 DOI: 10.3390/v16071061] [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: 06/05/2024] [Revised: 06/26/2024] [Accepted: 06/27/2024] [Indexed: 07/28/2024] Open
Abstract
Virus taxonomy uses a Linnaean-like subsumption hierarchy to classify viruses into taxonomic units at species and higher rank levels. Virus species are considered monophyletic groups of mobile genetic elements (MGEs) often delimited by the phylogenetic analysis of aligned genomic or metagenomic sequences. Taxonomic units are assumed to be independent organizational, functional and evolutionary units that follow a 'natural history' rationale. Here, I use phylogenomic and other arguments to show that viruses are not self-standing genetically-driven systems acting as evolutionary units. Instead, they are crucial components of holobionts, which are units of biological organization that dynamically integrate the genetics, epigenetic, physiological and functional properties of their co-evolving members. Remarkably, phylogenomic analyses show that viruses share protein domains and loops with cells throughout history via massive processes of reticulate evolution, helping spread evolutionary innovations across a wider taxonomic spectrum. Thus, viruses are not merely MGEs or microbes. Instead, their genomes and proteomes conduct cellularly integrated processes akin to those cataloged by the GO Consortium. This prompts the generation of compositional hierarchies that replace the 'is-a-kind-of' by a 'is-a-part-of' logic to better describe the mereology of integrated cellular and viral makeup. My analysis demands a new paradigm that integrates virus taxonomy into a modern evolutionarily centered taxonomy of organisms.
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Affiliation(s)
- Gustavo Caetano-Anollés
- Evolutionary Bioinformatics Laboratory, Department of Crop Sciences, C. R. Woese Institute for Genomic Biology, University of Illinois, Urbana, IL 61801, USA
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5
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Surmacz B, Stec D, Prus-Frankowska M, Buczek M, Michalczyk Ł, Łukasik P. Pinpointing the microbiota of tardigrades: What is really there? Environ Microbiol 2024; 26:e16659. [PMID: 38899728 DOI: 10.1111/1462-2920.16659] [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: 01/24/2024] [Accepted: 05/09/2024] [Indexed: 06/21/2024]
Abstract
Microbiota are considered significant in the biology of tardigrades, yet their diversity and distribution remain largely unexplored. This is partly due to the methodological challenges associated with studying the microbiota of small organisms that inhabit microbe-rich environments. In our study, we characterized the microbiota of 31 species of cultured tardigrades using 16S rRNA amplicon sequencing. We employed various sample preparation strategies and multiple types of controls and estimated the number of microbes in samples using synthetic DNA spike-ins. We also reanalysed data from previous tardigrade microbiome studies. Our findings suggest that the microbial communities of cultured tardigrades are predominantly composed of bacterial genotypes originating from food, medium, or reagents. Despite numerous experiments, we found it challenging to identify strains that were enriched in certain tardigrades, which would have indicated likely symbiotic associations. Putative tardigrade-associated microbes rarely constituted more than 20% of the datasets, although some matched symbionts identified in other studies. We also uncovered serious contamination issues in previous tardigrade microbiome studies, casting doubt on some of their conclusions. We concluded that tardigrades are not universally dependent on specialized microbes. Our work underscores the need for rigorous safeguards in studies of the microbiota of microscopic organisms and serves as a cautionary tale for studies involving samples with low microbiome abundance.
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Affiliation(s)
- Bartłomiej Surmacz
- Institute of Botany, Faculty of Biology, Jagiellonian University, Kraków, Poland
- Department of Invertebrate Evolution, Institute of Zoology and Biomedical Research, Faculty of Biology, Jagiellonian University, Kraków, Poland
- Doctoral School of Exact and Natural Sciences, Jagiellonian University, Kraków, Poland
| | - Daniel Stec
- Department of Invertebrate Evolution, Institute of Zoology and Biomedical Research, Faculty of Biology, Jagiellonian University, Kraków, Poland
- Institute of Systematics and Evolution of Animals, Polish Academy of Sciences, Kraków, Poland
| | - Monika Prus-Frankowska
- Institute of Environmental Sciences, Faculty of Biology, Jagiellonian University, Kraków, Poland
| | - Mateusz Buczek
- Institute of Environmental Sciences, Faculty of Biology, Jagiellonian University, Kraków, Poland
| | - Łukasz Michalczyk
- Department of Invertebrate Evolution, Institute of Zoology and Biomedical Research, Faculty of Biology, Jagiellonian University, Kraków, Poland
| | - Piotr Łukasik
- Institute of Environmental Sciences, Faculty of Biology, Jagiellonian University, Kraków, Poland
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6
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Keeling PJ. Horizontal gene transfer in eukaryotes: aligning theory with data. Nat Rev Genet 2024; 25:416-430. [PMID: 38263430 DOI: 10.1038/s41576-023-00688-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/06/2023] [Indexed: 01/25/2024]
Abstract
Horizontal gene transfer (HGT), or lateral gene transfer, is the non-sexual movement of genetic information between genomes. It has played a pronounced part in bacterial and archaeal evolution, but its role in eukaryotes is less clear. Behaviours unique to eukaryotic cells - phagocytosis and endosymbiosis - have been proposed to increase the frequency of HGT, but nuclear genomes encode fewer HGTs than bacteria and archaea. Here, I review the existing theory in the context of the growing body of data on HGT in eukaryotes, which suggests that any increased chance of acquiring new genes through phagocytosis and endosymbiosis is offset by a reduced need for these genes in eukaryotes, because selection in most eukaryotes operates on variation not readily generated by HGT.
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Affiliation(s)
- Patrick J Keeling
- Department of Botany, University of British Columbia, Vancouver, BC, Canada.
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Pratt CJ, Meili CH, Jones AL, Jackson DK, England EE, Wang Y, Hartson S, Rogers J, Elshahed MS, Youssef NH. Anaerobic fungi in the tortoise alimentary tract illuminate early stages of host-fungal symbiosis and Neocallimastigomycota evolution. Nat Commun 2024; 15:2714. [PMID: 38548766 PMCID: PMC10978972 DOI: 10.1038/s41467-024-47047-4] [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: 09/07/2023] [Accepted: 03/18/2024] [Indexed: 04/01/2024] Open
Abstract
Anaerobic gut fungi (AGF, Neocallimastigomycota) reside in the alimentary tract of herbivores. While their presence in mammals is well documented, evidence for their occurrence in non-mammalian hosts is currently sparse. Culture-independent surveys of AGF in tortoises identified a unique community, with three novel deep-branching genera representing >90% of sequences in most samples. Representatives of all genera were successfully isolated under strict anaerobic conditions. Transcriptomics-enabled phylogenomic and molecular dating analyses indicated an ancient, deep-branching position in the AGF tree for these genera, with an evolutionary divergence time estimate of 104-112 million years ago (Mya). Such estimates push the establishment of animal-Neocallimastigomycota symbiosis from the late to the early Cretaceous. Further, tortoise-associated isolates (T-AGF) exhibited limited capacity for plant polysaccharides metabolism and lacked genes encoding several carbohydrate-active enzyme (CAZyme) families. Finally, we demonstrate that the observed curtailed degradation capacities and reduced CAZyme repertoire is driven by the paucity of horizontal gene transfer (HGT) in T-AGF genomes, compared to their mammalian counterparts. This reduced capacity was reflected in an altered cellulosomal production capacity in T-AGF. Our findings provide insights into the phylogenetic diversity, ecological distribution, evolutionary history, evolution of fungal-host nutritional symbiosis, and dynamics of genes acquisition in Neocallimastigomycota.
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Affiliation(s)
- Carrie J Pratt
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, OK, USA
| | - Casey H Meili
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, OK, USA
| | - Adrienne L Jones
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, OK, USA
| | - Darian K Jackson
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, OK, USA
| | - Emma E England
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, OK, USA
| | - Yan Wang
- Department of Biological Sciences, University of Toronto Scarborough, Toronto, ON, Canada
| | - Steve Hartson
- Department of Biochemistry and Molecular Biology, Oklahoma State University, Stillwater, OK, USA
| | - Janet Rogers
- Department of Biochemistry and Molecular Biology, Oklahoma State University, Stillwater, OK, USA
| | - Mostafa S Elshahed
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, OK, USA
| | - Noha H Youssef
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, OK, USA.
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8
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Sylvester T, Adams R, Hunter WB, Li X, Rivera-Marchand B, Shen R, Shin NR, McKenna DD. The genome of the invasive and broadly polyphagous Diaprepes root weevil, Diaprepes abbreviatus (Coleoptera), reveals an arsenal of putative polysaccharide-degrading enzymes. J Hered 2024; 115:94-102. [PMID: 37878740 DOI: 10.1093/jhered/esad064] [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: 06/05/2023] [Revised: 09/14/2023] [Accepted: 10/23/2023] [Indexed: 10/27/2023] Open
Abstract
The Diaprepes root weevil (DRW), Diaprepes abbreviatus, is a broadly polyphagous invasive pest of agriculture in the southern United States and the Caribbean. Its genome was sequenced, assembled, and annotated to study genomic correlates of specialized plant-feeding and invasiveness and to facilitate the development of new methods for DRW control. The 1.69 Gb D. abbreviatus genome assembly was distributed across 653 contigs, with an N50 of 7.8 Mb and the largest contig of 62 Mb. Most of the genome was comprised of repetitive sequences, with 66.17% in transposable elements, 5.75% in macrosatellites, and 2.06% in microsatellites. Most expected orthologous genes were present and fully assembled, with 99.5% of BUSCO genes present and 1.5% duplicated. One hundred and nine contigs (27.19 Mb) were identified as putative fragments of the X and Y sex chromosomes, and homology assessment with other beetle X chromosomes indicated a possible sex chromosome turnover event. Genome annotation identified 18,412 genes, including 43 putative horizontally transferred (HT) loci. Notably, 258 genes were identified from gene families known to encode plant cell wall degrading enzymes and invertases, including carbohydrate esterases, polysaccharide lyases, and glycoside hydrolases (GH). GH genes were unusually numerous, with 239 putative genes representing 19 GH families. Interestingly, several other beetle species with large numbers of GH genes are (like D. abbreviatus) successful invasive pests of agriculture or forestry.
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Affiliation(s)
- Terrence Sylvester
- Department of Biological Sciences, University of Memphis, Memphis, TN 38152, United States
- Center for Biodiversity Research, University of Memphis, Memphis, TN 38152, United States
| | - Richard Adams
- Department of Entomology and Plant Pathology, University of Arkansas, Fayetteville, AR, United States
- Agricultural Statistics Laboratory, University of Arkansas, Fayetteville, AR, United States
| | - Wayne B Hunter
- USDA, ARS, U. S. Horticultural Research Laboratory, Fort Pierce, FL 34945, United States
| | - Xuankun Li
- Department of Biological Sciences, University of Memphis, Memphis, TN 38152, United States
- Center for Biodiversity Research, University of Memphis, Memphis, TN 38152, United States
- Department of Entomology, College of Plant Protection, China Agricultural University, Beijing 100193, China
| | - Bert Rivera-Marchand
- Office of Academic Affairs, Polk State College, Lakeland Campus, Lakeland, FL, 33803, United States
| | - Rongrong Shen
- Department of Biological Sciences, University of Memphis, Memphis, TN 38152, United States
- Center for Biodiversity Research, University of Memphis, Memphis, TN 38152, United States
| | - Na Ra Shin
- Department of Biological Sciences, University of Memphis, Memphis, TN 38152, United States
- Center for Biodiversity Research, University of Memphis, Memphis, TN 38152, United States
| | - Duane D McKenna
- Department of Biological Sciences, University of Memphis, Memphis, TN 38152, United States
- Center for Biodiversity Research, University of Memphis, Memphis, TN 38152, United States
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9
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Bálint B, Merényi Z, Hegedüs B, Grigoriev IV, Hou Z, Földi C, Nagy LG. ContScout: sensitive detection and removal of contamination from annotated genomes. Nat Commun 2024; 15:936. [PMID: 38296951 PMCID: PMC10831095 DOI: 10.1038/s41467-024-45024-5] [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: 01/06/2023] [Accepted: 01/08/2024] [Indexed: 02/02/2024] Open
Abstract
Contamination of genomes is an increasingly recognized problem affecting several downstream applications, from comparative evolutionary genomics to metagenomics. Here we introduce ContScout, a precise tool for eliminating foreign sequences from annotated genomes. It achieves high specificity and sensitivity on synthetic benchmark data even when the contaminant is a closely related species, outperforms competing tools, and can distinguish horizontal gene transfer from contamination. A screen of 844 eukaryotic genomes for contamination identified bacteria as the most common source, followed by fungi and plants. Furthermore, we show that contaminants in ancestral genome reconstructions lead to erroneous early origins of genes and inflate gene loss rates, leading to a false notion of complex ancestral genomes. Taken together, we offer here a tool for sensitive removal of foreign proteins, identify and remove contaminants from diverse eukaryotic genomes and evaluate their impact on phylogenomic analyses.
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Affiliation(s)
- Balázs Bálint
- Synthetic and Systems Biology Unit, HUN-REN Biological Research Centre, Szeged, Szeged, 6726, Hungary
| | - Zsolt Merényi
- Synthetic and Systems Biology Unit, HUN-REN Biological Research Centre, Szeged, Szeged, 6726, Hungary
| | - Botond Hegedüs
- Synthetic and Systems Biology Unit, HUN-REN Biological Research Centre, Szeged, Szeged, 6726, Hungary
| | - Igor V Grigoriev
- U.S. Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
- Department of Plant and Microbial Biology, University of California Berkeley, Berkeley, CA, 94720, USA
| | - Zhihao Hou
- Synthetic and Systems Biology Unit, HUN-REN Biological Research Centre, Szeged, Szeged, 6726, Hungary
- Doctoral School of Biology, Faculty of Science and Informatics, University of Szeged, Szeged, 6720, Hungary
| | - Csenge Földi
- Synthetic and Systems Biology Unit, HUN-REN Biological Research Centre, Szeged, Szeged, 6726, Hungary
- Doctoral School of Biology, Faculty of Science and Informatics, University of Szeged, Szeged, 6720, Hungary
| | - László G Nagy
- Synthetic and Systems Biology Unit, HUN-REN Biological Research Centre, Szeged, Szeged, 6726, Hungary.
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10
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Alvarez RV, Landsman D. GTax: improving de novo transcriptome assembly by removing foreign RNA contamination. Genome Biol 2024; 25:12. [PMID: 38191464 PMCID: PMC10773103 DOI: 10.1186/s13059-023-03141-2] [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: 06/08/2022] [Accepted: 12/08/2023] [Indexed: 01/10/2024] Open
Abstract
The cost and complexity of generating a complete reference genome means that many organisms lack an annotated reference. An alternative is to use a de novo reference transcriptome. This technology is cost-effective but is susceptible to off-target RNA contamination. In this manuscript, we present GTax, a taxonomy-structured database of genomic sequences that can be used with BLAST to detect and remove foreign contamination in RNA sequencing samples before assembly. In addition, we use a de novo transcriptome assembly of Solanum lycopersicum (tomato) to demonstrate that removing foreign contamination in sequencing samples reduces the number of assembled chimeric transcripts.
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Affiliation(s)
- Roberto Vera Alvarez
- Computational Biology Branch, National Center for Biotechnology Information, Intramural Research Program, National Library of Medicine, NIH, Bethesda, MD, USA
| | - David Landsman
- Computational Biology Branch, National Center for Biotechnology Information, Intramural Research Program, National Library of Medicine, NIH, Bethesda, MD, USA.
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11
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Matthews AE, Boves TJ, Percy KL, Schelsky WM, Wijeratne AJ. Population Genomics of Pooled Samples: Unveiling Symbiont Infrapopulation Diversity and Host-Symbiont Coevolution. Life (Basel) 2023; 13:2054. [PMID: 37895435 PMCID: PMC10608719 DOI: 10.3390/life13102054] [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: 06/29/2023] [Revised: 09/30/2023] [Accepted: 10/10/2023] [Indexed: 10/29/2023] Open
Abstract
Microscopic symbionts represent crucial links in biological communities. However, they present technical challenges in high-throughput sequencing (HTS) studies due to their small size and minimal high-quality DNA yields, hindering our understanding of host-symbiont coevolution at microevolutionary and macroevolutionary scales. One approach to overcome those barriers is to pool multiple individuals from the same infrapopulation (i.e., individual host) and sequence them together (Pool-Seq), but individual-level information is then compromised. To simultaneously address both issues (i.e., minimal DNA yields and loss of individual-level information), we implemented a strategic Pool-Seq approach to assess variation in sequencing performance and categorize genetic diversity (single nucleotide polymorphisms (SNPs)) at both the individual-level and infrapopulation-level for microscopic feather mites. To do so, we collected feathers harboring mites (Proctophyllodidae: Amerodectes protonotaria) from four individual Prothonotary Warblers (Parulidae: Protonotaria citrea). From each of the four hosts (i.e., four mite infrapopulations), we conducted whole-genome sequencing on three extraction pools consisting of different numbers of mites (1 mite, 5 mites, and 20 mites). We found that samples containing pools of multiple mites had more sequencing reads map to the feather mite reference genome than did the samples containing only a single mite. Mite infrapopulations were primarily genetically structured by their associated individual hosts (not pool size) and the majority of SNPs were shared by all pools within an infrapopulation. Together, these results suggest that the patterns observed are driven by evolutionary processes occurring at the infrapopulation level and are not technical signals due to pool size. In total, despite the challenges presented by microscopic symbionts in HTS studies, this work highlights the value of both individual-level and infrapopulation-level sequencing toward our understanding of host-symbiont coevolution at multiple evolutionary scales.
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Affiliation(s)
- Alix E. Matthews
- College of Sciences and Mathematics and Molecular Biosciences Program, Arkansas State University, Jonesboro, AR 72401, USA
- Department of Biological Sciences, Arkansas State University, Jonesboro, AR 72401, USA; (T.J.B.); (A.J.W.)
| | - Than J. Boves
- Department of Biological Sciences, Arkansas State University, Jonesboro, AR 72401, USA; (T.J.B.); (A.J.W.)
| | - Katie L. Percy
- Audubon Delta, National Audubon Society, Baton Rouge, LA 70808, USA;
- United States Department of Agriculture, Natural Resources Conservation Service, Addis, LA 70710, USA
| | - Wendy M. Schelsky
- Department of Evolution, Ecology, and Behavior, School of Integrative Biology, University of Illinois, Urbana-Champaign, Champaign, IL 61801, USA;
- Prairie Research Institute, Illinois Natural History Survey, University of Illinois, Urbana-Champaign, Champaign, IL 61820, USA
| | - Asela J. Wijeratne
- Department of Biological Sciences, Arkansas State University, Jonesboro, AR 72401, USA; (T.J.B.); (A.J.W.)
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12
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Maleki E, Akbari Rokn Abadi S, Koohi S. HELIOS: High-speed sequence alignment in optics. PLoS Comput Biol 2022; 18:e1010665. [PMID: 36409684 PMCID: PMC9678324 DOI: 10.1371/journal.pcbi.1010665] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2022] [Accepted: 10/18/2022] [Indexed: 11/22/2022] Open
Abstract
In response to the imperfections of current sequence alignment methods, originated from the inherent serialism within their corresponding electrical systems, a few optical approaches for biological data comparison have been proposed recently. However, due to their low performance, raised from their inefficient coding scheme, this paper presents a novel all-optical high-throughput method for aligning DNA, RNA, and protein sequences, named HELIOS. The HELIOS method employs highly sophisticated operations to locate character matches, single or multiple mutations, and single or multiple indels within various biological sequences. On the other hand, the HELIOS optical architecture exploits high-speed processing and operational parallelism in optics, by adopting wavelength and polarization of optical beams. For evaluation, the functionality and accuracy of the HELIOS method are approved through behavioral and optical simulation studies, while its complexity and performance are estimated through analytical computation. The accuracy evaluations indicate that the HELIOS method achieves a precise pairwise alignment of two sequences, highly similar to those of Smith-Waterman, Needleman-Wunsch, BLAST, MUSCLE, ClustalW, ClustalΩ, T-Coffee, Kalign, and MAFFT. According to our performance evaluations, the HELIOS optical architecture outperforms all alternative electrical and optical algorithms in terms of processing time and memory requirement, relying on its highly sophisticated method and optical architecture. Moreover, the employed compact coding scheme highly escalates the number of input characters, and hence, it offers reduced time and space complexities, compared to the electrical and optical alternatives. It makes the HELIOS method and optical architecture highly applicable for biomedical applications.
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Affiliation(s)
- Ehsan Maleki
- Department of Computer Engineering, Sharif University of Technology, Tehran, Iran
| | | | - Somayyeh Koohi
- Department of Computer Engineering, Sharif University of Technology, Tehran, Iran
- * E-mail:
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13
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Goudey B, Geard N, Verspoor K, Zobel J. Propagation, detection and correction of errors using the sequence database network. Brief Bioinform 2022; 23:6764545. [PMID: 36266246 PMCID: PMC9677457 DOI: 10.1093/bib/bbac416] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2022] [Revised: 07/31/2022] [Accepted: 08/28/2022] [Indexed: 12/14/2022] Open
Abstract
Nucleotide and protein sequences stored in public databases are the cornerstone of many bioinformatics analyses. The records containing these sequences are prone to a wide range of errors, including incorrect functional annotation, sequence contamination and taxonomic misclassification. One source of information that can help to detect errors are the strong interdependency between records. Novel sequences in one database draw their annotations from existing records, may generate new records in multiple other locations and will have varying degrees of similarity with existing records across a range of attributes. A network perspective of these relationships between sequence records, within and across databases, offers new opportunities to detect-or even correct-erroneous entries and more broadly to make inferences about record quality. Here, we describe this novel perspective of sequence database records as a rich network, which we call the sequence database network, and illustrate the opportunities this perspective offers for quantification of database quality and detection of spurious entries. We provide an overview of the relevant databases and describe how the interdependencies between sequence records across these databases can be exploited by network analyses. We review the process of sequence annotation and provide a classification of sources of error, highlighting propagation as a major source. We illustrate the value of a network perspective through three case studies that use network analysis to detect errors, and explore the quality and quantity of critical relationships that would inform such network analyses. This systematic description of a network perspective of sequence database records provides a novel direction to combat the proliferation of errors within these critical bioinformatics resources.
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Affiliation(s)
- Benjamin Goudey
- Corresponding author. Benjamin Goudey, School of Computing and Information Systems, University of Melbourne Parkville, Victoria, 3010,
| | - Nicholas Geard
- School of Computing and Information Systems, University of Melbourne Parkville, Victoria, 3010
| | - Karin Verspoor
- School of Computing Technologies, RMIT University Melbourne, Victoria, 3000
| | - Justin Zobel
- School of Computing and Information Systems, University of Melbourne Parkville, Victoria, 3010
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14
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Nguyen K, Kc S, Gonzalez T, Tapia H, Boothby TC. Trehalose and tardigrade CAHS proteins work synergistically to promote desiccation tolerance. Commun Biol 2022; 5:1046. [PMID: 36182981 PMCID: PMC9526748 DOI: 10.1038/s42003-022-04015-2] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2022] [Accepted: 09/20/2022] [Indexed: 11/28/2022] Open
Abstract
Tardigrades are microscopic animals renowned for their ability to survive extreme desiccation. Unlike many desiccation-tolerant organisms that accumulate high levels of the disaccharide trehalose to protect themselves during drying, tardigrades accumulate little or undetectable levels. Using comparative metabolomics, we find that despite being enriched at low levels, trehalose is a key biomarker distinguishing hydration states of tardigrades. In vitro, naturally occurring stoichiometries of trehalose and CAHS proteins, intrinsically disordered proteins with known protective capabilities, were found to produce synergistic protective effects during desiccation. In vivo, this synergistic interaction is required for robust CAHS-mediated protection. This demonstrates that trehalose acts not only as a protectant, but also as a synergistic cosolute. Beyond desiccation tolerance, our study provides insights into how the solution environment tunes intrinsically disordered proteins’ functions, many of which are vital in biological contexts such as development and disease that are concomitant with large changes in intracellular chemistry. The disaccharide trehalose is a synergistic cosolute and key biomarker of desiccation tolerance in tardigrades.
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Affiliation(s)
- Kenny Nguyen
- University of Wyoming, Department of Molecular Biology, Laramie, WY, USA
| | - Shraddha Kc
- University of Wyoming, Department of Molecular Biology, Laramie, WY, USA
| | - Tyler Gonzalez
- University of Wyoming, Department of Molecular Biology, Laramie, WY, USA
| | - Hugo Tapia
- California State University-Channel Islands, Biology Program, Camarillo, CA, USA
| | - Thomas C Boothby
- University of Wyoming, Department of Molecular Biology, Laramie, WY, USA.
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15
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Yu M. Computational analysis on two putative mitochondrial protein-coding genes from the Emydura subglobosa genome: A functional annotation approach. PLoS One 2022; 17:e0268031. [PMID: 35981005 PMCID: PMC9387794 DOI: 10.1371/journal.pone.0268031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2021] [Accepted: 04/21/2022] [Indexed: 11/19/2022] Open
Abstract
Rapid advancements in automated genomic technologies have uncovered many unique findings about the turtle genome and its associated features including olfactory gene expansions and duplications of toll-like receptors. However, despite the advent of large-scale sequencing, assembly, and annotation, about 40-50% of genes in eukaryotic genomes are left without functional annotation, severely limiting our knowledge of the biological information of genes. Additionally, these automated processes are prone to errors since draft genomes consist of several disconnected scaffolds whose order is unknown; erroneous draft assemblies may also be contaminated with foreign sequences and propagate to cause errors in annotation. Many of these automated annotations are thus incomplete and inaccurate, highlighting the need for functional annotation to link gene sequences to biological identity. In this study, we have functionally annotated two genes of the red-bellied short-neck turtle (Emydura subglobosa), a member of the relatively understudied pleurodire lineage of turtles. We improved upon initial ab initio gene predictions through homology-based evidence and generated refined consensus gene models. Through functional, localization, and structural analyses of the predicted proteins, we discovered conserved putative genes encoding mitochondrial proteins that play a role in C21-steroid hormone biosynthetic processes and fatty acid catabolism-both of which are distantly related by the tricarboxylic acid (TCA) cycle and share similar metabolic pathways. Overall, these findings further our knowledge about the genetic features underlying turtle physiology, morphology, and longevity, which have important implications for the treatment of human diseases and evolutionary studies.
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Affiliation(s)
- Megan Yu
- Department of Molecular, Cell & Developmental Biology, University of California–Los Angeles, Los Angeles, California, United States of America
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16
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Yoshida Y, Tanaka S. Deciphering the Biological Enigma-Genomic Evolution Underlying Anhydrobiosis in the Phylum Tardigrada and the Chironomid Polypedilum vanderplanki. INSECTS 2022; 13:557. [PMID: 35735894 PMCID: PMC9224920 DOI: 10.3390/insects13060557] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Revised: 06/13/2022] [Accepted: 06/17/2022] [Indexed: 02/04/2023]
Abstract
Anhydrobiosis, an ametabolic dehydrated state triggered by water loss, is observed in several invertebrate lineages. Anhydrobiotes revive when rehydrated, and seem not to suffer the ultimately lethal cell damage that results from severe loss of water in other organisms. Here, we review the biochemical and genomic evidence that has revealed the protectant molecules, repair systems, and maintenance pathways associated with anhydrobiosis. We then introduce two lineages in which anhydrobiosis has evolved independently: Tardigrada, where anhydrobiosis characterizes many species within the phylum, and the genus Polypedilum, where anhydrobiosis occurs in only two species. Finally, we discuss the complexity of the evolution of anhydrobiosis within invertebrates based on current knowledge, and propose perspectives to enhance the understanding of anhydrobiosis.
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Affiliation(s)
- Yuki Yoshida
- Graduate School of Arts and Sciences, The University of Tokyo, 3-8-1 Komaba, Meguro-ku, Tokyo 153-8902, Japan
| | - Sae Tanaka
- Exploratory Research Center on Life and Living Systems (ExCELLS), National Institutes of Natural Sciences, 5-1 Higashiyama, Myodaiji, Okazaki 444-8787, Japan
- Institute for Advanced Biosciences, Keio University, 341-1 Mizukami, Tsuruoka 997-0052, Japan
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17
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Intragenomic variation in nuclear ribosomal markers and its implication in species delimitation, identification and barcoding in fungi. FUNGAL BIOL REV 2022. [DOI: 10.1016/j.fbr.2022.04.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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18
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Abstract
Experimentally tractable organisms like C. elegans, Drosophila, zebrafish, and mouse are popular models for addressing diverse questions in biology. In 1997, two of the most valuable invertebrate model organisms to date-C. elegans and Drosophila-were found to be much more closely related to each other than expected. C. elegans and Drosophila belong to the nematodes and arthropods, respectively, and these two phyla and six other phyla make up a clade of molting animals referred to as the Ecdysozoa. The other ecdysozoan phyla could be valuable models for comparative biology, taking advantage of the rich and continual sources of research findings as well as tools from both C. elegans and Drosophila. But when the Ecdysozoa was first recognized, few tools were available for laboratory studies in any of these six other ecdysozoan phyla. In 1999 I began an effort to develop tools for studying one such phylum, the tardigrades. Here, I describe how the tardigrade species Hypsibius exemplaris and tardigrades more generally have emerged over the past two decades as valuable new models for answering diverse questions. To date, these questions have included how animal body plans evolve and how biological materials can survive some remarkably extreme conditions.
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Affiliation(s)
- Bob Goldstein
- Department of Biology and Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States.
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19
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Cornet L, Baurain D. Contamination detection in genomic data: more is not enough. Genome Biol 2022; 23:60. [PMID: 35189924 PMCID: PMC8862208 DOI: 10.1186/s13059-022-02619-9] [Citation(s) in RCA: 31] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2021] [Accepted: 01/18/2022] [Indexed: 12/20/2022] Open
Abstract
The decreasing cost of sequencing and concomitant augmentation of publicly available genomes have created an acute need for automated software to assess genomic contamination. During the last 6 years, 18 programs have been published, each with its own strengths and weaknesses. Deciding which tools to use becomes more and more difficult without an understanding of the underlying algorithms. We review these programs, benchmarking six of them, and present their main operating principles. This article is intended to guide researchers in the selection of appropriate tools for specific applications. Finally, we present future challenges in the developing field of contamination detection.
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Affiliation(s)
- Luc Cornet
- BCCM/IHEM, Mycology and Aerobiology, Sciensano, Bruxelles, Belgium
| | - Denis Baurain
- InBioS-PhytoSYSTEMS, Eukaryotic Phylogenomics, University of Liège, Liège, Belgium.
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20
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Abstract
Tardigrades are ubiquitous meiofauna that are especially renowned for their exceptional extremotolerance to various adverse environments, including pressure, temperature, and even ionizing radiation. This is achieved through a reversible halt of metabolism triggered by desiccation, a phenomenon called anhydrobiosis. Recent establishment of genome resources for two tardigrades, Hypsibius exemplaris and Ramazzottius varieornatus, accelerated research to uncover the molecular mechanisms behind anhydrobiosis, leading to the discovery of many tardigrade-unique proteins. This review focuses on the history, methods, discoveries, and current state and challenges regarding tardigrade genomics, with an emphasis on molecular anhydrobiology. Remaining questions and future perspectives regarding prospective approaches to fully elucidate the molecular machinery of this complex phenomenon are discussed.
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Affiliation(s)
- Kazuharu Arakawa
- Institute for Advanced Biosciences, Keio University, Daishouji, Tsuruoka, Yamagata, Japan; .,Faculty of Environment and Information Studies, Keio University, Fujisawa, Kanagawa, Japan.,Graduate School of Media and Governance, Systems Biology Program, Keio University, Fujisawa, Kanagawa, Japan.,Exploratory Research Center on Life and Living Systems (ExCELLS), National Institute of Natural Sciences, Myodaiji, Okazaki, Aichi, Japan
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21
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Cooley NP, Wright ES. Accurate annotation of protein coding sequences with IDTAXA. NAR Genom Bioinform 2021; 3:lqab080. [PMID: 34541527 PMCID: PMC8445202 DOI: 10.1093/nargab/lqab080] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Revised: 07/07/2021] [Accepted: 08/25/2021] [Indexed: 11/12/2022] Open
Abstract
The observed diversity of protein coding sequences continues to increase far more rapidly than knowledge of their functions, making classification algorithms essential for assigning a function to proteins using only their sequence. Most pipelines for annotating proteins rely on searches for homologous sequences in databases of previously annotated proteins using BLAST or HMMER. Here, we develop a new approach for classifying proteins into a taxonomy of functions and demonstrate its utility for genome annotation. Our algorithm, IDTAXA, was more accurate than BLAST or HMMER at assigning sequences to KEGG ortholog groups. Moreover, IDTAXA correctly avoided classifying sequences with novel functions to existing groups, which is a common error mode for classification approaches that rely on E-values as a proxy for confidence. We demonstrate IDTAXA's utility for annotating eukaryotic and prokaryotic genomes by assigning functions to proteins within a multi-level ontology and applied IDTAXA to detect genome contamination in eukaryotic genomes. Finally, we re-annotated 8604 microbial genomes with known antibiotic resistance phenotypes to discover two novel associations between proteins and antibiotic resistance. IDTAXA is available as a web tool (http://DECIPHER.codes/Classification.html) or as part of the open source DECIPHER R package from Bioconductor.
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Affiliation(s)
- Nicholas P Cooley
- Department of Biomedical Informatics, University of Pittsburgh, Pittsburgh, PA 15206, USA
| | - Erik S Wright
- Department of Biomedical Informatics, University of Pittsburgh, Pittsburgh, PA 15206, USA
- Center for Evolutionary Biology and Medicine, Pittsburgh, PA 15219, USA
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22
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Hazan R, Schoemann M, Klutstein M. Endurance of extremely prolonged nutrient prevention across kingdoms of life. iScience 2021; 24:102745. [PMID: 34258566 PMCID: PMC8258982 DOI: 10.1016/j.isci.2021.102745] [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] [Indexed: 12/17/2022] Open
Abstract
Numerous observations demonstrate that microorganisms can survive very long periods of nutrient deprivation and starvation. Moreover, it is evident that prolonged periods of starvation are a feature of many habitats, and many cells in all kingdoms of life are found in prolonged starvation conditions. Bacteria exhibit a range of responses to long-term starvation. These include genetic adaptations such as the long-term stationary phase and the growth advantage in stationary phase phenotypes characterized by mutations in stress-signaling genes and elevated mutation rates. Here, we suggest using the term "endurance of prolonged nutrient prevention" (EPNP phase), to describe this phase, which was also recently described in eukaryotes. Here, we review this literature and describe the current knowledge about the adaptations to very long-term starvation conditions in bacteria and eukaryotes, its conceptual and structural conservation across all kingdoms of life, and point out possible directions that merit further research.
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Affiliation(s)
- Ronen Hazan
- Institute of Biomedical and Oral Research, Faculty of Dental Medicine, The Hebrew University of Jerusalem, P.O.B. 12272, Ein Kerem, Jerusalem 9112001, Israel
| | - Miriam Schoemann
- Institute of Biomedical and Oral Research, Faculty of Dental Medicine, The Hebrew University of Jerusalem, P.O.B. 12272, Ein Kerem, Jerusalem 9112001, Israel
| | - Michael Klutstein
- Institute of Biomedical and Oral Research, Faculty of Dental Medicine, The Hebrew University of Jerusalem, P.O.B. 12272, Ein Kerem, Jerusalem 9112001, Israel
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23
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Kobayashi K, Kim J, Fukuda Y, Kozawa T, Inoue T. Fields, biochemistry fast autooxidation of a Bis-Histidyl-ligated globin from the anhydrobiotic tardigrade, ramazzottius varieornatus, by molecular oxygen. J Biochem 2021; 169:663-673. [PMID: 33479760 DOI: 10.1093/jb/mvab003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2020] [Accepted: 12/27/2020] [Indexed: 01/11/2023] Open
Abstract
Tardigrades, a phylum of meiofaunal organisms, exhibit extraordinary tolerance to various environmental conditions, including extreme temperatures (-272 to 151 °C) and exposure to ionizing radiation. Proteins from anhydrobiotic tardigrades with homology to known proteins from other organisms are new potential targets for structural genomics. Recently, we reported spectroscopic and structural characterization of a hexacoordinated hemoglobin (Kumaglobin [Kgb]) found in an anhydrobiotic tardigrade. In the absence of its exogenous ligand, Kgb displays hexacoordination with distal and proximal histidines. In this work, we analyzed binding of the molecular oxygen ligand following reduction of heme in Kgb using a pulse radiolysis technique. Radiolytically generated hydrated electrons (eaq-) reduced the heme iron of Kgb within 20 µs. Subsequently, ferrous heme reacted with O2 to form a ferrous-dioxygen intermediate with a second-order rate constant of 3.0 × 106 M-1 s-1. The intermediate was rapidly (within 0.1 s) autooxidized to the ferric form. Redox potential measurements revealed an E'0 of -400 mV (vs. SHE) in the ferric/ferrous couple. Our results suggest that Kgb may serve as a physiological generator of O2·- via redox signaling and/or electron transfer.
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Affiliation(s)
- Kazuo Kobayashi
- The Institute of Scientific and Industrial Research, Osaka University, Mihogaoka 8-1, Ibaraki, Osaka 567-0047, Japan
| | - JeeEun Kim
- Graduate School of Pharmaceutical Science, Osaka University, Suita, Japan
| | - Yohta Fukuda
- Graduate School of Pharmaceutical Science, Osaka University, Suita, Japan
| | - Takahiro Kozawa
- The Institute of Scientific and Industrial Research, Osaka University, Mihogaoka 8-1, Ibaraki, Osaka 567-0047, Japan
| | - Tsuyoshi Inoue
- Graduate School of Pharmaceutical Science, Osaka University, Suita, Japan
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24
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Reiter T, Brooks† PT, Irber† L, Joslin† SEK, Reid† CM, Scott† C, Brown CT, Pierce-Ward NT. Streamlining data-intensive biology with workflow systems. Gigascience 2021; 10:giaa140. [PMID: 33438730 PMCID: PMC8631065 DOI: 10.1093/gigascience/giaa140] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2020] [Revised: 11/06/2020] [Accepted: 11/13/2020] [Indexed: 11/14/2022] Open
Abstract
As the scale of biological data generation has increased, the bottleneck of research has shifted from data generation to analysis. Researchers commonly need to build computational workflows that include multiple analytic tools and require incremental development as experimental insights demand tool and parameter modifications. These workflows can produce hundreds to thousands of intermediate files and results that must be integrated for biological insight. Data-centric workflow systems that internally manage computational resources, software, and conditional execution of analysis steps are reshaping the landscape of biological data analysis and empowering researchers to conduct reproducible analyses at scale. Adoption of these tools can facilitate and expedite robust data analysis, but knowledge of these techniques is still lacking. Here, we provide a series of strategies for leveraging workflow systems with structured project, data, and resource management to streamline large-scale biological analysis. We present these practices in the context of high-throughput sequencing data analysis, but the principles are broadly applicable to biologists working beyond this field.
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Affiliation(s)
- Taylor Reiter
- Department of Population Health and Reproduction, University of California, Davis, 1 Shields Avenue, Davis, CA 95616, USA
| | - Phillip T Brooks†
- Department of Population Health and Reproduction, University of California, Davis, 1 Shields Avenue, Davis, CA 95616, USA
| | - Luiz Irber†
- Department of Population Health and Reproduction, University of California, Davis, 1 Shields Avenue, Davis, CA 95616, USA
| | - Shannon E K Joslin†
- Department of Animal Science, University of California, Davis, 1 Shields Avenue, Davis, CA 95616, USA
| | - Charles M Reid†
- Department of Population Health and Reproduction, University of California, Davis, 1 Shields Avenue, Davis, CA 95616, USA
| | - Camille Scott†
- Department of Population Health and Reproduction, University of California, Davis, 1 Shields Avenue, Davis, CA 95616, USA
| | - C Titus Brown
- Department of Population Health and Reproduction, University of California, Davis, 1 Shields Avenue, Davis, CA 95616, USA
| | - N Tessa Pierce-Ward
- Department of Population Health and Reproduction, University of California, Davis, 1 Shields Avenue, Davis, CA 95616, USA
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25
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Horizontal Gene Transfer in Eukaryotes: Not if, but How Much? Trends Genet 2020; 36:915-925. [DOI: 10.1016/j.tig.2020.08.006] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2020] [Revised: 07/31/2020] [Accepted: 08/10/2020] [Indexed: 12/17/2022]
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26
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Conservative route to genome compaction in a miniature annelid. Nat Ecol Evol 2020; 5:231-242. [PMID: 33199869 PMCID: PMC7854359 DOI: 10.1038/s41559-020-01327-6] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2020] [Accepted: 09/15/2020] [Indexed: 12/14/2022]
Abstract
The causes and consequences of genome reduction in animals are unclear because our understanding of this process mostly relies on lineages with often exceptionally high rates of evolution. Here, we decode the compact 73.8-megabase genome of Dimorphilus gyrociliatus, a meiobenthic segmented worm. The D. gyrociliatus genome retains traits classically associated with larger and slower-evolving genomes, such as an ordered, intact Hox cluster, a generally conserved developmental toolkit and traces of ancestral bilaterian linkage. Unlike some other animals with small genomes, the analysis of the D. gyrociliatus epigenome revealed canonical features of genome regulation, excluding the presence of operons and trans-splicing. Instead, the gene-dense D. gyrociliatus genome presents a divergent Myc pathway, a key physiological regulator of growth, proliferation and genome stability in animals. Altogether, our results uncover a conservative route to genome compaction in annelids, reminiscent of that observed in the vertebrate Takifugu rubripes. This study reports the genome of the miniature segmented annelid Dimorphilus gyrociliatus and reveals no drastic changes in genome architecture and regulation, unlike other cases of genome miniaturization.
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27
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Hesgrove C, Boothby TC. The biology of tardigrade disordered proteins in extreme stress tolerance. Cell Commun Signal 2020; 18:178. [PMID: 33148259 PMCID: PMC7640644 DOI: 10.1186/s12964-020-00670-2] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Accepted: 09/29/2020] [Indexed: 02/06/2023] Open
Abstract
Abstract Disordered proteins have long been known to help mediate tolerance to different abiotic stresses including freezing, osmotic stress, high temperatures, and desiccation in a diverse set of organisms. Recently, three novel families of intrinsically disordered proteins were identified in tardigrades, microscopic animals capable of surviving a battery of environmental extremes. These three families include the Cytoplasmic-, Secreted-, and Mitochondrial- Abundant Heat Soluble (CAHS, SAHS, and MAHS) proteins, which are collectively termed Tardigrade Disordered Proteins (TDPs). At the level of sequence conservation TDPs are unique to tardigrades, and beyond their high degree of disorder the CAHS, SAHS, and MAHS families do not resemble one another. All three families are either highly expressed constitutively, or significantly enriched in response to desiccation. In vivo, ex vivo, and in vitro experiments indicate functional roles for members of each TDP family in mitigating cellular perturbations induced by various abiotic stresses. What is currently lacking is a comprehensive and holistic understanding of the fundamental mechanisms by which TDPs function, and the properties of TDPs that allow them to function via those mechanisms. A quantitative and systematic approach is needed to identify precisely what cellular damage TDPs work to prevent, what sequence features are important for these functions, and how those sequence features contribute to the underlying mechanisms of protection. Such an approach will inform us not only about these fascinating proteins, but will also provide insights into how the sequence of a disordered protein can dictate its functional, structural, and dynamic properties. Video Abstract
Graphical abstract ![]()
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Affiliation(s)
- Cherie Hesgrove
- Department of Molecular Biology, University of Wyoming, Laramie, WY, 82071, USA
| | - Thomas C Boothby
- Department of Molecular Biology, University of Wyoming, Laramie, WY, 82071, USA.
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28
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Sun X, Zhu S, Li N, Cheng Y, Zhao J, Qiao X, Lu L, Liu S, Wang Y, Liu C, Li B, Guo W, Gao S, Yang Z, Li F, Zeng Z, Tang Q, Pan Y, Guan M, Zhao J, Lu X, Meng H, Han Z, Gao C, Jiang W, Zhao X, Tian S, Su J, Cheng Z, Liu T. A Chromosome-Level Genome Assembly of Garlic (Allium sativum) Provides Insights into Genome Evolution and Allicin Biosynthesis. MOLECULAR PLANT 2020; 13:1328-1339. [PMID: 32730994 DOI: 10.1016/j.molp.2020.07.019] [Citation(s) in RCA: 66] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/02/2020] [Revised: 06/26/2020] [Accepted: 07/27/2020] [Indexed: 05/21/2023]
Abstract
Garlic, an economically important vegetable, spice, and medicinal crop, produces highly enlarged bulbs and unique organosulfur compounds. Here, we report a chromosome-level genome assembly for garlic, with a total size of approximately 16.24 Gb, as well as the annotation of 57 561 predicted protein-coding genes, making garlic the first Allium species with a sequenced genome. Analysis of this garlic genome assembly reveals a recent burst of transposable elements, explaining the substantial expansion of the garlic genome. We examined the evolution of certain genes associated with the biosynthesis of allicin and inulin neoseries-type fructans, and provided new insights into the biosynthesis of these two compounds. Furthermore, a large-scale transcriptome was produced to characterize the expression patterns of garlic genes in different tissues and at various growth stages of enlarged bulbs. The reference genome and large-scale transcriptome data generated in this study provide valuable new resources for research on garlic biology and breeding.
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Affiliation(s)
- Xiudong Sun
- Shandong Agricultural University, Tai'an 271018, China
| | - Siyuan Zhu
- Institute of Bast Fiber Crops, Chinese Academy of Agricultural Sciences, Changsha 410205, China
| | - Ningyang Li
- Shandong Agricultural University, Tai'an 271018, China
| | - Yi Cheng
- Institute of Bast Fiber Crops, Chinese Academy of Agricultural Sciences, Changsha 410205, China
| | - Jing Zhao
- Novogene Bioinformatics Institute, Beijing 100083, China
| | - Xuguang Qiao
- Shandong Agricultural University, Tai'an 271018, China
| | - Li Lu
- School of Pharmaceutical Sciences, Wuhan University, Wuhan 430071, China
| | - Shiqi Liu
- Shandong Agricultural University, Tai'an 271018, China
| | - Yanzhou Wang
- Institute of Bast Fiber Crops, Chinese Academy of Agricultural Sciences, Changsha 410205, China
| | - Chan Liu
- Institute of Bast Fiber Crops, Chinese Academy of Agricultural Sciences, Changsha 410205, China
| | - Benping Li
- Novogene Bioinformatics Institute, Beijing 100083, China
| | - Wu Guo
- Novogene Bioinformatics Institute, Beijing 100083, China
| | - Shuang Gao
- Novogene Bioinformatics Institute, Beijing 100083, China
| | - Zemao Yang
- Institute of Bast Fiber Crops, Chinese Academy of Agricultural Sciences, Changsha 410205, China
| | - Fu Li
- Institute of Bast Fiber Crops, Chinese Academy of Agricultural Sciences, Changsha 410205, China
| | - Zheng Zeng
- Institute of Bast Fiber Crops, Chinese Academy of Agricultural Sciences, Changsha 410205, China
| | - Qing Tang
- Institute of Bast Fiber Crops, Chinese Academy of Agricultural Sciences, Changsha 410205, China
| | - Yupeng Pan
- Northwest A&F University, Yangling 712100, China
| | - Mengjiao Guan
- Shandong Agricultural University, Tai'an 271018, China
| | - Jian Zhao
- Novogene Bioinformatics Institute, Beijing 100083, China
| | - Xiaoming Lu
- Shandong Agricultural University, Tai'an 271018, China
| | - Huanwen Meng
- Northwest A&F University, Yangling 712100, China
| | - Zhenlin Han
- Shandong Agricultural University, Tai'an 271018, China
| | - Chunsheng Gao
- Institute of Bast Fiber Crops, Chinese Academy of Agricultural Sciences, Changsha 410205, China
| | - Wenkai Jiang
- Novogene Bioinformatics Institute, Beijing 100083, China
| | - Xing Zhao
- Novogene Bioinformatics Institute, Beijing 100083, China
| | - Shilin Tian
- Novogene Bioinformatics Institute, Beijing 100083, China
| | - Jianguang Su
- Institute of Bast Fiber Crops, Chinese Academy of Agricultural Sciences, Changsha 410205, China.
| | - Zhihui Cheng
- Northwest A&F University, Yangling 712100, China.
| | - Touming Liu
- Institute of Bast Fiber Crops, Chinese Academy of Agricultural Sciences, Changsha 410205, China.
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29
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Game M, Smith FW. Loss of intermediate regions of perpendicular body axes contributed to miniaturization of tardigrades. Proc Biol Sci 2020; 287:20201135. [PMID: 33043863 DOI: 10.1098/rspb.2020.1135] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Tardigrades have a miniaturized body plan. Miniaturization in tardigrades is associated with the loss of several organ systems and an intermediate region of their anteroposterior (AP) axis. However, how miniaturization has affected tardigrade legs is unclear. In arthropods and in onychophorans, the leg gap genes are expressed in regionalized proximodistal (PD) patterns in the legs. Functional studies indicate that these genes regulate growth in their respective expression domains and establish PD identities, partly through mutually antagonistic regulatory interactions. Here, we investigated the expression patterns of tardigrade orthologs of the leg gap genes. Rather than being restricted to a proximal leg region, as in arthropods and onychophorans, we detected coexpression of orthologues of homothorax and extradenticle broadly across the legs of the first three trunk segments in the tardigrade Hypsibius exemplaris. We could not identify a dachshund orthologue in tardigrade genomes, a gene that is expressed in an intermediate region of developing legs in arthropods and onychophorans, suggesting that this gene was lost in the tardigrade lineage. We detected Distal-less expression broadly across all developing leg buds in H. exemplaris embryos, unlike in arthropods and onychophorans, in which it exhibits a distally restricted expression domain. The broad expression patterns of the remaining leg gap genes in H. exemplaris legs may reflect the loss of dachshund and the accompanying loss of an intermediate region of the legs in the tardigrade lineage. We propose that the loss of intermediate regions of both the AP and PD body axes contributed to miniaturization of Tardigrada.
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Affiliation(s)
- Mandy Game
- Biology Department, University of North Florida, USA
| | - Frank W Smith
- Biology Department, University of North Florida, USA
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30
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Li X, Fang C, Zhao JP, Zhou XY, Ni Z, Niu DK. Desiccation does not drastically increase the accessibility of exogenous DNA to nuclear genomes: evidence from the frequency of endosymbiotic DNA transfer. BMC Genomics 2020; 21:452. [PMID: 32611311 PMCID: PMC7329468 DOI: 10.1186/s12864-020-06865-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2019] [Accepted: 06/23/2020] [Indexed: 12/04/2022] Open
Abstract
Background Although horizontal gene transfer (HGT) is a widely accepted force in the evolution of prokaryotic genomes, its role in the evolution of eukaryotic genomes remains hotly debated. Some bdelloid rotifers that are resistant to extreme desiccation and radiation undergo a very high level of HGT, whereas in another desiccation-resistant invertebrate, the tardigrade, the pattern does not exist. Overall, the DNA double-strand breaks (DSBs) induced by prolonged desiccation have been postulated to open a gateway to the nuclear genome for exogenous DNA integration and thus to facilitate the HGT process, thereby enhancing the rate of endosymbiotic DNA transfer (EDT). Results We first surveyed the abundance of nuclear mitochondrial DNAs (NUMTs) and nuclear plastid DNAs (NUPTs) in five eukaryotes that are highly resistant to desiccation: the bdelloid rotifers Adineta vaga and Adineta ricciae, the tardigrade Ramazzottius varieornatus, and the resurrection plants Dorcoceras hygrometricum and Selaginella tamariscina. Excessive NUMTs or NUPTs were not detected. Furthermore, we compared 24 groups of desiccation-tolerant organisms with their relatively less desiccation-tolerant relatives but did not find a significant difference in NUMT/NUPT contents. Conclusions Desiccation may induce DSBs, but it is unlikely to dramatically increase the frequency of exogenous sequence integration in most eukaryotes. The capture of exogenous DNA sequences is possible only when DSBs are repaired through a subtype of non-homologous end joining, named alternative end joining (alt-EJ). Due to the deleterious effects of the resulting insertion mutations, alt-EJ is less frequently initiated than other mechanisms.
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Affiliation(s)
- Xixi Li
- MOE Key Laboratory for Biodiversity Science and Ecological Engineering and Beijing Key Laboratory of Gene Resource and Molecular Development, College of Life Sciences, Beijing Normal University, Beijing, 100875, China
| | - Cheng Fang
- MOE Key Laboratory for Biodiversity Science and Ecological Engineering and Beijing Key Laboratory of Gene Resource and Molecular Development, College of Life Sciences, Beijing Normal University, Beijing, 100875, China
| | - Jun-Peng Zhao
- MOE Key Laboratory for Biodiversity Science and Ecological Engineering and Beijing Key Laboratory of Gene Resource and Molecular Development, College of Life Sciences, Beijing Normal University, Beijing, 100875, China
| | - Xiao-Yu Zhou
- MOE Key Laboratory for Biodiversity Science and Ecological Engineering and Beijing Key Laboratory of Gene Resource and Molecular Development, College of Life Sciences, Beijing Normal University, Beijing, 100875, China
| | - Zhihua Ni
- MOE Key Laboratory for Biodiversity Science and Ecological Engineering and Beijing Key Laboratory of Gene Resource and Molecular Development, College of Life Sciences, Beijing Normal University, Beijing, 100875, China.,College of Life Sciences, Hebei University, Baoding, 071002, China
| | - Deng-Ke Niu
- MOE Key Laboratory for Biodiversity Science and Ecological Engineering and Beijing Key Laboratory of Gene Resource and Molecular Development, College of Life Sciences, Beijing Normal University, Beijing, 100875, China.
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31
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Emamalipour M, Seidi K, Zununi Vahed S, Jahanban-Esfahlan A, Jaymand M, Majdi H, Amoozgar Z, Chitkushev LT, Javaheri T, Jahanban-Esfahlan R, Zare P. Horizontal Gene Transfer: From Evolutionary Flexibility to Disease Progression. Front Cell Dev Biol 2020; 8:229. [PMID: 32509768 PMCID: PMC7248198 DOI: 10.3389/fcell.2020.00229] [Citation(s) in RCA: 63] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Accepted: 03/17/2020] [Indexed: 12/11/2022] Open
Abstract
Flexibility in the exchange of genetic material takes place between different organisms of the same or different species. This phenomenon is known to play a key role in the genetic, physiological, and ecological performance of the host. Exchange of genetic materials can cause both beneficial and/or adverse biological consequences. Horizontal gene transfer (HGT) or lateral gene transfer (LGT) as a general mechanism leads to biodiversity and biological innovations in nature. HGT mediators are one of the genetic engineering tools used for selective introduction of desired changes in the genome for gene/cell therapy purposes. HGT, however, is crucial in development, emergence, and recurrence of various human-related diseases, such as cancer, genetic-, metabolic-, and neurodegenerative disorders and can negatively affect the therapeutic outcome by promoting resistant forms or disrupting the performance of genome editing toolkits. Because of the importance of HGT and its vital physio- and pathological roles, here the variety of HGT mechanisms are reviewed, ranging from extracellular vesicles (EVs) and nanotubes in prokaryotes to cell-free DNA and apoptotic bodies in eukaryotes. Next, we argue that HGT plays a role both in the development of useful features and in pathological states associated with emerging and recurrent forms of the disease. A better understanding of the different HGT mediators and their genome-altering effects/potentials may pave the way for the development of more effective therapeutic and diagnostic regimes.
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Affiliation(s)
- Melissa Emamalipour
- Drug Applied Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Khaled Seidi
- Biotechnology Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | | | | | - Mehdi Jaymand
- Nano Drug Delivery Research Center, Health Technology Institute, Kermanshah University of Medical Sciences, Kermanshah, Iran
| | - Hasan Majdi
- Department of Medical Nanotechnology, Faculty of Advanced Medical Sciences, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Zohreh Amoozgar
- Edwin L. Steele Laboratories, Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, United States
| | - L T Chitkushev
- Department of Computer Science, Metropolitan College, Boston University, Boston, MA, United States.,Health Informatics Lab, Metropolitan College, Boston University, Boston, MA, United States
| | - Tahereh Javaheri
- Health Informatics Lab, Metropolitan College, Boston University, Boston, MA, United States
| | - Rana Jahanban-Esfahlan
- Department of Medical Biotechnology, School of Advanced Medical Sciences, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Peyman Zare
- Faculty of Medicine, Cardinal Stefan Wyszyński University in Warsaw, Warsaw, Poland.,Dioscuri Center of Chromatin Biology and Epigenomics, Nencki Institute of Experimental Biology, Polish Academy of Sciences, Warsaw, Poland
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32
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Chen LX, Anantharaman K, Shaiber A, Eren AM, Banfield JF. Accurate and complete genomes from metagenomes. Genome Res 2020; 30:315-333. [PMID: 32188701 PMCID: PMC7111523 DOI: 10.1101/gr.258640.119] [Citation(s) in RCA: 203] [Impact Index Per Article: 50.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Genomes are an integral component of the biological information about an organism; thus, the more complete the genome, the more informative it is. Historically, bacterial and archaeal genomes were reconstructed from pure (monoclonal) cultures, and the first reported sequences were manually curated to completion. However, the bottleneck imposed by the requirement for isolates precluded genomic insights for the vast majority of microbial life. Shotgun sequencing of microbial communities, referred to initially as community genomics and subsequently as genome-resolved metagenomics, can circumvent this limitation by obtaining metagenome-assembled genomes (MAGs); but gaps, local assembly errors, chimeras, and contamination by fragments from other genomes limit the value of these genomes. Here, we discuss genome curation to improve and, in some cases, achieve complete (circularized, no gaps) MAGs (CMAGs). To date, few CMAGs have been generated, although notably some are from very complex systems such as soil and sediment. Through analysis of about 7000 published complete bacterial isolate genomes, we verify the value of cumulative GC skew in combination with other metrics to establish bacterial genome sequence accuracy. The analysis of cumulative GC skew identified potential misassemblies in some reference genomes of isolated bacteria and the repeat sequences that likely gave rise to them. We discuss methods that could be implemented in bioinformatic approaches for curation to ensure that metabolic and evolutionary analyses can be based on very high-quality genomes.
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Affiliation(s)
- Lin-Xing Chen
- Department of Earth and Planetary Sciences, University of California, Berkeley, California 94720, USA
| | - Karthik Anantharaman
- Department of Earth and Planetary Sciences, University of California, Berkeley, California 94720, USA
| | - Alon Shaiber
- Graduate Program in Biophysical Sciences, University of Chicago, Chicago, Illinois 60637, USA.,Department of Medicine, University of Chicago, Chicago, Illinois 60637, USA
| | - A Murat Eren
- Department of Medicine, University of Chicago, Chicago, Illinois 60637, USA.,Bay Paul Center, Marine Biological Laboratory, Woods Hole, Massachusetts 02543, USA
| | - Jillian F Banfield
- Department of Earth and Planetary Sciences, University of California, Berkeley, California 94720, USA.,Department of Environmental Science, Policy, and Management, University of California, Berkeley, California 94720, USA.,Earth and Environmental Sciences, Lawrence Berkeley National Laboratory, University of California, Berkeley, California 94720, USA
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33
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Ultrastructural analysis of the dehydrated tardigrade Hypsibius exemplaris unveils an anhydrobiotic-specific architecture. Sci Rep 2020; 10:4324. [PMID: 32152342 PMCID: PMC7062702 DOI: 10.1038/s41598-020-61165-1] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2019] [Accepted: 02/18/2020] [Indexed: 01/06/2023] Open
Abstract
Tardigrades can cope with adverse environmental conditions by turning into anhydrobiotes with a characteristic tun shape. Tun formation is an essential morphological adaptation for tardigrade entry into the anhydrobiotic state. The tun cell structure and ultrastructure have rarely been explored in tardigrades in general and never in Hypsibius exemplaris. We used transmission electron microscopy to compare cellular organization and ultrastructures between hydrated and anhydrobiotic H. exemplaris. Despite a globally similar cell organelle structure and a number of cells not significantly different between hydrated and desiccated tardigrades, reductions in the sizes of both cells and mitochondria were detected in dehydrated animals. Moreover, in anhydrobiotes, secretory active cells with a dense endoplasmic reticulum network were observed. Interestingly, these anhydrobiote-specific cells are in a close relationship with a specific extracellular structure surrounding each cell. It is possible that this rampart-like extracellular structure resulted from the accumulation of anhydrobiotic-specific material to protect the cells. Interestingly, after five hours of rehydration, the number of secretory cells decreased, and the specific extracellular structure began to disappear. Twenty-four hours after the beginning of rehydration, the cellular structure and ultrastructure were comparable to those observed in hydrated tardigrades.
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34
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Chalmers TJ, Wu LE. Transposable Elements Cross Kingdom Boundaries and Contribute to Inflammation and Ageing: Somatic Acquisition of Foreign Transposable Elements as a Catalyst of Genome Instability, Epigenetic Dysregulation, Inflammation, Senescence, and Ageing. Bioessays 2020; 42:e1900197. [PMID: 31994769 DOI: 10.1002/bies.201900197] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2019] [Revised: 12/23/2019] [Indexed: 01/07/2023]
Abstract
The de-repression of transposable elements (TEs) in mammalian genomes is thought to contribute to genome instability, inflammation, and ageing, yet is viewed as a cell-autonomous event. In contrast to mammalian cells, prokaryotes constantly exchange genetic material through TEs, crossing both cell and species barriers, contributing to rapid microbial evolution and diversity in complex communities such as the mammalian gut. Here, it is proposed that TEs released from prokaryotes in the microbiome or from pathogenic infections regularly cross the kingdom barrier to the somatic cells of their eukaryotic hosts. It is proposed this horizontal transfer of TEs from microbe to host is a stochastic, ongoing catalyst of genome destabilization, resulting in structural and epigenetic variations, and activation of well-evolved host defense mechanisms contributing to inflammation, senescence, and biological ageing. It is proposed that innate immunity pathways defend against the horizontal acquisition of microbial TEs, and that activation of this pathway during horizontal transposon transfer promotes chronic inflammation during ageing. Finally, it is suggested that horizontal acquisition of prokaryotic TEs into mammalian genomes has been masked and subsequently under-reported due to flaws in current sequencing pipelines, and new strategies to uncover these events are proposed.
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Affiliation(s)
| | - Lindsay E Wu
- School of Medical Sciences, UNSW, Sydney, NSW, 2052, Australia
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35
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Kaczmarek Ł, Roszkowska M, Poprawa I, Janelt K, Kmita H, Gawlak M, Fiałkowska E, Mioduchowska M. Integrative description of bisexual Paramacrobiotus experimentalis sp. nov. (Macrobiotidae) from republic of Madagascar (Africa) with microbiome analysis. Mol Phylogenet Evol 2020; 145:106730. [PMID: 31904510 DOI: 10.1016/j.ympev.2019.106730] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2019] [Revised: 12/31/2019] [Accepted: 12/31/2019] [Indexed: 12/26/2022]
Abstract
In a moss samples collected on Madagascar two populations of Paramacrobiotus experimentalis sp. nov. were found. Paramacrobiotus experimentalis sp. nov. with the presence of a microplacoid and areolatus type of eggs is similar to Pam. danielae, Pam. garynahi, Pam. hapukuensis, Pam. peteri, Pam. rioplatensis and Pam. savai, but it differs from them by some morphological and morphometric characters of the eggs. The p-distance between two COI haplotypes of Pam. experimentalis sp. nov. was 0.17%. In turn, the ranges of uncorrected genetic p-distances of all Paramacrobiotus species available in GenBank was from 18.27% (for Pam. lachowskae) to 25.26% (for Pam. arduus) with an average distance of 20.67%. We also found that Pam. experimentalis sp. nov. is bisexual. This observation was congruent on three levels: (i) morphological - specimen size dimorphism; (ii) structural (primary sexual characteristics) - females have an unpaired ovary while males have an unpaired testis and (iii) molecular - heterozygous and homozygous strains of the ITS-2 marker. Although symbiotic associations of hosts with bacteria (including endosymbiotic bacteria) are common in nature and these interactions exert various effects on the evolution, biology and reproductive ecology of hosts, there is still very little information on the bacterial community associated with tardigrades. To fill this gap and characterise the bacterial community of Pam. experimentalis sp. nov. populations and microbiome of its microhabitat, high throughput sequencing of the V3-V4 hypervariable regions in the bacterial 16S rRNA gene fragment was performed. The obtained 16S rRNA gene sequences ranged from 92,665 to 131,163. In total, 135 operational taxonomic units (OTUs) were identified across the rarefied dataset. Overall, both Pam. experimentalis sp. nov. populations were dominated by OTUs ascribed to the phylum Proteobacteria (89-92%) and Firmicutes (6-7%). In the case of samples from tardigrades' laboratory habitat, the most abundant bacterial phylum was Proteobacteria (51-90%) and Bacteroides (9-48%). In all compared microbiome profiles, only 16 of 137 OTUs were shared. We found also significant differences in beta diversity between the partly species-specific microbiome of Pam. experimentalis sp. nov. and its culturing environment. Two OTUs belonging to a putative bacterial endosymbiont were identified - Rickettsiales and Polynucleobacter. We also demonstrated that each bacterial community was rich in genes involved in membrane transport, amino acid metabolism, and carbohydrate metabolism.
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Affiliation(s)
- Łukasz Kaczmarek
- Department of Animal Taxonomy and Ecology, Faculty of Biology, Adam Mickiewicz University, Poznan, Uniwersytetu Poznańskiego 6, 61-614 Poznań, Poland.
| | - Milena Roszkowska
- Department of Animal Taxonomy and Ecology, Faculty of Biology, Adam Mickiewicz University, Poznan, Uniwersytetu Poznańskiego 6, 61-614 Poznań, Poland; Department of Bioenergetics, Faculty of Biology, Adam Mickiewicz University, Poznan, Uniwersytetu Poznańskiego 6, 61-614 Poznań, Poland.
| | - Izabela Poprawa
- Institute of Biology, Biotechnology and Environmental Protection, Faculty of Natural Sciences, University of Silesia in Katowice, Bankowa 9, 40-007 Katowice, Poland.
| | - Kamil Janelt
- Institute of Biology, Biotechnology and Environmental Protection, Faculty of Natural Sciences, University of Silesia in Katowice, Bankowa 9, 40-007 Katowice, Poland
| | - Hanna Kmita
- Department of Bioenergetics, Faculty of Biology, Adam Mickiewicz University, Poznan, Uniwersytetu Poznańskiego 6, 61-614 Poznań, Poland.
| | - Magdalena Gawlak
- The Institute of Plant Protection-National Research Institute, Węgorka 20, 60-318 Poznań, Poland.
| | - Edyta Fiałkowska
- Institute of Environmental Sciences, Jagiellonian University, Gronostajowa 7, 30-387 Kraków, Poland.
| | - Monika Mioduchowska
- Department of Genetics and Biosystematics, Faculty of Biology, University of Gdańsk, Gdańsk, Wita Stwosza 59, 80-308 Gdańsk, Poland.
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36
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Finding relationships among biological entities. LOGIC AND CRITICAL THINKING IN THE BIOMEDICAL SCIENCES 2020. [PMCID: PMC7499094 DOI: 10.1016/b978-0-12-821364-3.00005-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Confusion over the concepts of “relationships” and “similarities” lies at the heart of many battles over the direction and intent of research projects. Here is a short story that demonstrates the difference between the two concepts: You look up at the clouds, and you begin to see the shape of a lion. The cloud has a tail, like a lion’s tale, and a fluffy head, like a lion’s mane. With a little imagination the mouth of the lion seems to roar down from the sky. You have succeeded in finding similarities between the cloud and a lion. If you look at a cloud and you imagine a tea kettle producing a head of steam and you recognize that the physical forces that create a cloud and the physical forces that produced steam from a heated kettle are the same, then you have found a relationship. Most popular classification algorithms operate by grouping together data objects that have similar properties or values. In so doing, they may miss finding the true relationships among objects. Traditionally, relationships among data objects are discovered by an intellectual process. In this chapter, we will discuss the scientific gains that come when we classify biological entities by relationships, not by their similarities.
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37
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Wickell DA, Li FW. On the evolutionary significance of horizontal gene transfers in plants. THE NEW PHYTOLOGIST 2020; 225:113-117. [PMID: 31347197 DOI: 10.1111/nph.16022] [Citation(s) in RCA: 48] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/02/2019] [Accepted: 06/04/2019] [Indexed: 05/05/2023]
Abstract
Horizontal gene transfer (HGT) has long been seen as a crucial process in the evolution of prokaryotic species, but until recently it was thought to have little, if any, effect on the evolution of eukaryotic life forms. Detecting and describing HGT events in eukaryotes is difficult, making this phenomenon at times controversial. However, modern advances in genomics and bioinformatics have radically altered our view of HGT in eukaryotes, especially in plants. It now appears that HGT to and from plant lineages is more common than previously suspected. Importantly, the transfer of functional nuclear genes with adaptive significance has been reported in numerous taxa. Here we review several recent studies that have found evidence of the horizontal transfer of nuclear genes, and argue that HGT has undoubtedly had profound impacts on plant evolution as a whole.
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Affiliation(s)
- David A Wickell
- Boyce Thompson Institute, Ithaca, NY, 14853, USA
- Plant Biology Section, Cornell University, New York, NY, 14853, USA
| | - Fay-Wei Li
- Boyce Thompson Institute, Ithaca, NY, 14853, USA
- Plant Biology Section, Cornell University, New York, NY, 14853, USA
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38
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Guidetti R, Vecchi M, Ferrari A, Newton ILG, Cesari M, Rebecchi L. Further insights in the Tardigrada microbiome: phylogenetic position and prevalence of infection of four new Alphaproteobacteria putative endosymbionts. Zool J Linn Soc 2019. [DOI: 10.1093/zoolinnean/zlz128] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Abstract
Data from a previous study showed that microbiomes of six tardigrade species are species-specific and distinct from associated environmental microbes. We here performed a more in-depth analyses of those data, to identify and characterize new potential symbionts. The most abundant bacterial operational taxonomic units (OTUs) found in tardigrades are classified, and their prevalence in other environments is assessed using public databases. A subset of OTUs was selected for molecular phylogenetic analyses based on their affiliation with host-associated bacterial families in tardigrades. Almost 22.6% of the most abundant OTUs found do not match any sequence at 99% identity in the IMNGS database. These novel OTUs include four putative tardigrade endosymbionts from Alphaproteobacteria (Anaplasmataceae and Candidatus Tenuibacteraceae), which are characterized by 16S rRNA gene analysis and investigated for their infection rates in: Echiniscus trisetosus, Richtersisus coronifer and Macrobiotus macrocalix. These putative endosymbionts have an infection prevalence between 9.1% and 40.0%, and are, therefore, likely secondary symbionts, not essential for tardigrade survival and reproduction. Using fluorescence in situ hybridization (FISH), we detected bacteria on the cuticle and within the ovary of E. trisetosus, suggesting possible vertical transmission. This study highlights the great contribution in biodiversity discovery that neglected phyla can provide in microbiome and symbiosis studies.
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Affiliation(s)
- Roberto Guidetti
- Department of Life Sciences, University of Modena and Reggio Emilia, Modena, Italy
| | - Matteo Vecchi
- Department of Life Sciences, University of Modena and Reggio Emilia, Modena, Italy
- Department of Biological and Environmental Science, University of Jyvaskyla, University of Jyvaskyla, Finland
| | - Agnese Ferrari
- Department of Life Sciences, University of Modena and Reggio Emilia, Modena, Italy
| | | | - Michele Cesari
- Department of Life Sciences, University of Modena and Reggio Emilia, Modena, Italy
| | - Lorena Rebecchi
- Department of Life Sciences, University of Modena and Reggio Emilia, Modena, Italy
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39
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Boothby TC. Mechanisms and evolution of resistance to environmental extremes in animals. EvoDevo 2019; 10:30. [PMID: 31827759 PMCID: PMC6862762 DOI: 10.1186/s13227-019-0143-4] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2019] [Accepted: 11/02/2019] [Indexed: 11/25/2022] Open
Abstract
When animals are exposed to an extreme environmental stress, one of three possible outcomes takes place: the animal dies, the animal avoids the environmental stress and survives, or the animal tolerates the environmental stress and survives. This review is concerned with the third possibility, and will look at mechanisms that rare animals use to survive extreme environmental stresses including freezing, desiccation, intense heat, irradiation, and low-oxygen conditions (hypoxia). In addition, an increasing understanding of the molecular mechanisms involved in environmental stress tolerance allows us to speculate on how these tolerances arose. Uncovering the mechanisms of extreme environmental stress tolerance and how they evolve has broad implications for our understanding of the evolution of early life on this planet, colonization of new environments, and the search for novel forms of life both on Earth and elsewhere, as well as a number of agricultural and health-related applications.
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Affiliation(s)
- Thomas C Boothby
- Department of Molecular Biology, University of Wyoming, Laramie, WY USA
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40
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Afzal M, Park J, Destgeer G, Ahmed H, Iqrar SA, Kim S, Kang S, Alazzam A, Yoon TS, Sung HJ. Acoustomicrofluidic separation of tardigrades from raw cultures for sample preparation. Zool J Linn Soc 2019. [DOI: 10.1093/zoolinnean/zlz079] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Abstract
Tardigrades are microscopic animals widely known for their ability to survive in extreme conditions. They are the focus of current research in the fields of taxonomy, biogeography, genomics, proteomics, development, space biology, evolution and ecology. Tardigrades, such as Hypsibius exemplaris, are being advocated as a next-generation model organism for genomic and developmental studies. The raw culture of H. exemplaris usually contains tardigrades themselves, their eggs, faeces and algal food. Experimentation with tardigrades often requires the demanding and laborious separation of tardigrades from raw samples to prepare pure and contamination-free tardigrade samples. In this paper, we propose a two-step acoustomicrofluidic separation method to isolate tardigrades from raw samples. In the first step, a passive microfluidic filter composed of an array of traps is used to remove large algal clusters in the raw sample. In the second step, a surface acoustic wave-based active microfluidic separation device is used to deflect tardigrades continuously from their original streamlines inside the microchannel and thus isolate them selectively from algae and eggs. The experimental results demonstrated the efficient separation of tardigrades, with a recovery rate of 96% and an impurity of 4% algae on average in a continuous, contactless, automated, rapid and biocompatible manner.
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Affiliation(s)
- Muhammad Afzal
- Department of Mechanical Engineering, KAIST, Daejeon 34141, Korea
| | - Jinsoo Park
- Department of Mechanical Engineering, KAIST, Daejeon 34141, Korea
| | - Ghulam Destgeer
- Department of Mechanical Engineering, KAIST, Daejeon 34141, Korea
| | - Husnain Ahmed
- Department of Mechanical Engineering, KAIST, Daejeon 34141, Korea
| | - Syed Atif Iqrar
- Department of Mechanical Engineering, KAIST, Daejeon 34141, Korea
| | - Sanghee Kim
- Division of Polar Life Sciences, KOPRI, Incheon 21990, Korea
| | - Sunghyun Kang
- Department of Proteome Structural Biology, KRIBB, Daejeon 34141, Korea
| | - Anas Alazzam
- Department of Mechanical Engineering, Khalifa University, Abu Dhabi 127788, United Arab Emirates
| | - Tae-Sung Yoon
- Department of Proteome Structural Biology, KRIBB, Daejeon 34141, Korea
| | - Hyung Jin Sung
- Department of Mechanical Engineering, KAIST, Daejeon 34141, Korea
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Kamilari M, Jørgensen A, Schiøtt M, Møbjerg N. Comparative transcriptomics suggest unique molecular adaptations within tardigrade lineages. BMC Genomics 2019; 20:607. [PMID: 31340759 PMCID: PMC6652013 DOI: 10.1186/s12864-019-5912-x] [Citation(s) in RCA: 51] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2018] [Accepted: 06/17/2019] [Indexed: 12/19/2022] Open
Abstract
Background Tardigrades are renowned for their ability to enter cryptobiosis (latent life) and endure extreme stress, including desiccation and freezing. Increased focus is on revealing molecular mechanisms underlying this tolerance. Here, we provide the first transcriptomes from the heterotardigrade Echiniscoides cf. sigismundi and the eutardigrade Richtersius cf. coronifer, and compare these with data from other tardigrades and six eukaryote models. Investigating 107 genes/gene families, our study provides a thorough analysis of tardigrade gene content with focus on stress tolerance. Results E. cf. sigismundi, a strong cryptobiont, apparently lacks expression of a number of stress related genes. Most conspicuous is the lack of transcripts from genes involved in classical Non-Homologous End Joining. Our analyses suggest that post-cryptobiotic survival in tardigrades could rely on high fidelity transcription-coupled DNA repair. Tardigrades seem to lack many peroxins, but they all have a comprehensive number of genes encoding proteins involved in antioxidant defense. The “tardigrade unique proteins” (CAHS, SAHS, MAHS, RvLEAM), seem to be missing in the heterotardigrade lineage, revealing that cryptobiosis in general cannot be attributed solely to these proteins. Our investigation further reveals a unique and highly expressed cold shock domain. We hypothesize that the cold shock protein acts as a RNA-chaperone involved in regulation of translation following freezing. Conclusions Our results show common gene family contractions and expansions within stress related gene pathways in tardigrades, but also indicate that evolutionary lineages have a high degree of divergence. Different taxa and lineages may exhibit unique physiological adaptations towards stress conditions involving possible unknown functional homologues and/or novel physiological and biochemical mechanisms. To further substantiate the current results genome assemblies coupled with transcriptome data and experimental investigations are needed from tardigrades belonging to different evolutionary lineages. Electronic supplementary material The online version of this article (10.1186/s12864-019-5912-x) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Maria Kamilari
- Section for Cell Biology and Physiology, Department of Biology, August Krogh Building, University of Copenhagen, Universitetsparken 13, Copenhagen, Denmark
| | - Aslak Jørgensen
- Section for Cell Biology and Physiology, Department of Biology, August Krogh Building, University of Copenhagen, Universitetsparken 13, Copenhagen, Denmark
| | - Morten Schiøtt
- Section for Ecology and Evolution, Department of Biology, University of Copenhagen, Universitetsparken 15, Copenhagen, Denmark
| | - Nadja Møbjerg
- Section for Cell Biology and Physiology, Department of Biology, August Krogh Building, University of Copenhagen, Universitetsparken 13, Copenhagen, Denmark.
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42
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Horizontal Gene Transfer as an Indispensable Driver for Evolution of Neocallimastigomycota into a Distinct Gut-Dwelling Fungal Lineage. Appl Environ Microbiol 2019; 85:AEM.00988-19. [PMID: 31126947 DOI: 10.1128/aem.00988-19] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2019] [Accepted: 05/19/2019] [Indexed: 01/01/2023] Open
Abstract
Survival and growth of the anaerobic gut fungi (AGF; Neocallimastigomycota) in the herbivorous gut necessitate the possession of multiple abilities absent in other fungal lineages. We hypothesized that horizontal gene transfer (HGT) was instrumental in forging the evolution of AGF into a phylogenetically distinct gut-dwelling fungal lineage. The patterns of HGT were evaluated in the transcriptomes of 27 AGF strains, 22 of which were isolated and sequenced in this study, and 4 AGF genomes broadly covering the breadth of AGF diversity. We identified 277 distinct incidents of HGT in AGF transcriptomes, with subsequent gene duplication resulting in an HGT frequency of 2 to 3.5% in AGF genomes. The majority of HGT events were AGF specific (91.7%) and wide (70.8%), indicating their occurrence at early stages of AGF evolution. The acquired genes allowed AGF to expand their substrate utilization range, provided new venues for electron disposal, augmented their biosynthetic capabilities, and facilitated their adaptation to anaerobiosis. The majority of donors were anaerobic fermentative bacteria prevalent in the herbivorous gut. This study strongly indicates that HGT indispensably forged the evolution of AGF as a distinct fungal phylum and provides a unique example of the role of HGT in shaping the evolution of a high-rank taxonomic eukaryotic lineage.IMPORTANCE The anaerobic gut fungi (AGF) represent a distinct basal phylum lineage (Neocallimastigomycota) commonly encountered in the rumen and alimentary tracts of herbivores. Survival and growth of anaerobic gut fungi in these anaerobic, eutrophic, and prokaryote-dominated habitats necessitates the acquisition of several traits absent in other fungal lineages. We assess here the role of horizontal gene transfer as a relatively fast mechanism for trait acquisition by the Neocallimastigomycota postsequestration in the herbivorous gut. Analysis of 27 transcriptomes that represent the broad diversity of Neocallimastigomycota identified 277 distinct HGT events, with subsequent gene duplication resulting in an HGT frequency of 2 to 3.5% in AGF genomes. These HGT events have allowed AGF to survive in the herbivorous gut by expanding their substrate utilization range, augmenting their biosynthetic pathway, providing new routes for electron disposal by expanding fermentative capacities, and facilitating their adaptation to anaerobiosis. HGT in the AGF is also shown to be mainly a cross-kingdom affair, with the majority of donors belonging to the bacteria. This study represents a unique example of the role of HGT in shaping the evolution of a high-rank taxonomic eukaryotic lineage.
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43
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Abstract
The amount and evolutionary impact of horizontal gene transfer in eukaryotes remain contentious issues. A new phylogenomic study suggests that gene transfer from prokaryotes has contributed significantly to the adaptation and metabolic evolution of Blastocystis, the most widespread human gut eukaryotic parasite.
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44
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Rossoni AW, Price DC, Seger M, Lyska D, Lammers P, Bhattacharya D, Weber APM. The genomes of polyextremophilic cyanidiales contain 1% horizontally transferred genes with diverse adaptive functions. eLife 2019; 8:e45017. [PMID: 31149898 PMCID: PMC6629376 DOI: 10.7554/elife.45017] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2019] [Accepted: 05/30/2019] [Indexed: 01/08/2023] Open
Abstract
The role and extent of horizontal gene transfer (HGT) in eukaryotes are hotly disputed topics that impact our understanding of the origin of metabolic processes and the role of organelles in cellular evolution. We addressed this issue by analyzing 10 novel Cyanidiales genomes and determined that 1% of their gene inventory is HGT-derived. Numerous HGT candidates share a close phylogenetic relationship with prokaryotes that live in similar habitats as the Cyanidiales and encode functions related to polyextremophily. HGT candidates differ from native genes in GC-content, number of splice sites, and gene expression. HGT candidates are more prone to loss, which may explain the absence of a eukaryotic pan-genome. Therefore, the lack of a pan-genome and cumulative effects fail to provide substantive arguments against our hypothesis of recurring HGT followed by differential loss in eukaryotes. The maintenance of 1% HGTs, even under selection for genome reduction, underlines the importance of non-endosymbiosis related foreign gene acquisition.
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Affiliation(s)
- Alessandro W Rossoni
- Institute of Plant Biochemistry, Cluster of Excellence on Plant Sciences (CEPLAS)Heinrich Heine UniversityDüsseldorfGermany
| | - Dana C Price
- Department of Plant BiologyRutgers UniversityNew BrunswickUnited States
| | - Mark Seger
- Arizona Center for Algae Technology and InnovationArizona State UniversityMesaUnited States
| | - Dagmar Lyska
- Institute of Plant Biochemistry, Cluster of Excellence on Plant Sciences (CEPLAS)Heinrich Heine UniversityDüsseldorfGermany
| | - Peter Lammers
- Arizona Center for Algae Technology and InnovationArizona State UniversityMesaUnited States
| | | | - Andreas PM Weber
- Institute of Plant Biochemistry, Cluster of Excellence on Plant Sciences (CEPLAS)Heinrich Heine UniversityDüsseldorfGermany
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45
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Breitwieser FP, Pertea M, Zimin AV, Salzberg SL. Human contamination in bacterial genomes has created thousands of spurious proteins. Genome Res 2019; 29:954-960. [PMID: 31064768 PMCID: PMC6581058 DOI: 10.1101/gr.245373.118] [Citation(s) in RCA: 81] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2018] [Accepted: 05/03/2019] [Indexed: 01/22/2023]
Abstract
Contaminant sequences that appear in published genomes can cause numerous problems for downstream analyses, particularly for evolutionary studies and metagenomics projects. Our large-scale scan of complete and draft bacterial and archaeal genomes in the NCBI RefSeq database reveals that 2250 genomes are contaminated by human sequence. The contaminant sequences derive primarily from high-copy human repeat regions, which themselves are not adequately represented in the current human reference genome, GRCh38. The absence of the sequences from the human assembly offers a likely explanation for their presence in bacterial assemblies. In some cases, the contaminating contigs have been erroneously annotated as containing protein-coding sequences, which over time have propagated to create spurious protein “families” across multiple prokaryotic and eukaryotic genomes. As a result, 3437 spurious protein entries are currently present in the widely used nr and TrEMBL protein databases. We report here an extensive list of contaminant sequences in bacterial genome assemblies and the proteins associated with them. We found that nearly all contaminants occurred in small contigs in draft genomes, which suggests that filtering out small contigs from draft genome assemblies may mitigate the issue of contamination while still keeping nearly all of the genuine genomic sequences.
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Affiliation(s)
- Florian P Breitwieser
- Center for Computational Biology, McKusick-Nathans Institute of Genetic Medicine, Johns Hopkins School of Medicine, Baltimore, Maryland 21205, USA
| | - Mihaela Pertea
- Center for Computational Biology, McKusick-Nathans Institute of Genetic Medicine, Johns Hopkins School of Medicine, Baltimore, Maryland 21205, USA.,Department of Computer Science, Whiting School of Engineering, Johns Hopkins University, Baltimore, Maryland 21218, USA
| | - Aleksey V Zimin
- Center for Computational Biology, McKusick-Nathans Institute of Genetic Medicine, Johns Hopkins School of Medicine, Baltimore, Maryland 21205, USA.,Department of Biomedical Engineering, Johns Hopkins University, Baltimore, Maryland 21218, USA
| | - Steven L Salzberg
- Center for Computational Biology, McKusick-Nathans Institute of Genetic Medicine, Johns Hopkins School of Medicine, Baltimore, Maryland 21205, USA.,Department of Computer Science, Whiting School of Engineering, Johns Hopkins University, Baltimore, Maryland 21218, USA.,Department of Biomedical Engineering, Johns Hopkins University, Baltimore, Maryland 21218, USA.,Department of Biostatistics, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, Maryland 21205, USA
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46
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Kaczmarek Ł, Roszkowska M, Fontaneto D, Jezierska M, Pietrzak B, Wieczorek R, Poprawa I, Kosicki JZ, Karachitos A, Kmita H. Staying young and fit? Ontogenetic and phylogenetic consequences of animal anhydrobiosis. J Zool (1987) 2019. [DOI: 10.1111/jzo.12677] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
- Ł. Kaczmarek
- Department of Animal Taxonomy and Ecology Faculty of Biology Adam Mickiewicz University in Poznan Poznań Poland
| | - M. Roszkowska
- Department of Animal Taxonomy and Ecology Faculty of Biology Adam Mickiewicz University in Poznan Poznań Poland
- Department of Bioenergetics Institute of Molecular Biology and Biotechnology Faculty of Biology Adam Mickiewicz University in Poznan Poznań Poland
| | - D. Fontaneto
- National Research Council Water Research Institute (CNR‐IRSA) Verbania Italy
| | - M. Jezierska
- Department of Animal Histology and Embryology University of Silesia in Katowice Katowice Poland
| | - B. Pietrzak
- Department of Hydrobiology Faculty of Biology Biological and Chemical Research Centre University of Warsaw Warszawa Poland
| | - R. Wieczorek
- Faculty of Chemistry University of Warsaw Warsaw Poland
| | - I. Poprawa
- Department of Animal Histology and Embryology University of Silesia in Katowice Katowice Poland
| | - J. Z. Kosicki
- Department of Avian Biology and Ecology Faculty of Biology Adam Mickiewicz University Poznan Poznań Poland
| | - A. Karachitos
- Department of Bioenergetics Institute of Molecular Biology and Biotechnology Faculty of Biology Adam Mickiewicz University in Poznan Poznań Poland
| | - H. Kmita
- Department of Bioenergetics Institute of Molecular Biology and Biotechnology Faculty of Biology Adam Mickiewicz University in Poznan Poznań Poland
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47
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Laumer CE. Inferring Ancient Relationships with Genomic Data: A Commentary on Current Practices. Integr Comp Biol 2019; 58:623-639. [PMID: 29982611 DOI: 10.1093/icb/icy075] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Contemporary phylogeneticists enjoy an embarrassment of riches, not only in the volumes of data now available, but also in the diversity of bioinformatic tools for handling these data. Here, I discuss a subset of these tools I consider well-suited to the task of inferring ancient relationships with coding sequence data in particular, encompassing data generation, orthology assignment, alignment and gene tree inference, supermatrix construction, and analysis under the best-fitting models applicable to large-scale datasets. Throughout, I compare and critique methods, considering both their theoretical principles and the details of their implementation, and offering practical tips on usage where appropriate. I also entertain different motivations for analyzing what are almost always originally DNA sequence data as codons, amino acids, and higher-order recodings. Although presented in a linear order, I see value in using the diversity of tools available to us to assess the sensitivity of clades of biological interest to different gene and taxon sets and analytical modes, which can be an indication of the presence of systematic error, of which a few forms remain poorly controlled by even the best available inference methods.
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Affiliation(s)
- Christopher E Laumer
- EMBL-European Bioinformatics Institute, Wellcome Trust Genome Campus, EBML-EBI South Building, Hinxton CB10 1SD, UK
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48
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Piszkiewicz S, Gunn KH, Warmuth O, Propst A, Mehta A, Nguyen KH, Kuhlman E, Guseman AJ, Stadmiller SS, Boothby TC, Neher SB, Pielak GJ. Protecting activity of desiccated enzymes. Protein Sci 2019; 28:941-951. [PMID: 30868674 DOI: 10.1002/pro.3604] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2019] [Revised: 03/11/2019] [Accepted: 03/12/2019] [Indexed: 01/04/2023]
Abstract
Protein-based biological drugs and many industrial enzymes are unstable, making them prohibitively expensive. Some can be stabilized by formulation with excipients, but most still require low temperature storage. In search of new, more robust excipients, we turned to the tardigrade, a microscopic animal that synthesizes cytosolic abundant heat soluble (CAHS) proteins to protect its cellular components during desiccation. We find that CAHS proteins protect the test enzymes lactate dehydrogenase and lipoprotein lipase against desiccation-, freezing-, and lyophilization-induced deactivation. Our data also show that a variety of globular and disordered protein controls, with no known link to desiccation tolerance, protect our test enzymes. Protection of lactate dehydrogenase correlates, albeit imperfectly, with the charge density of the protein additive, suggesting an approach to tune protection by modifying charge. Our results support the potential use of CAHS proteins as stabilizing excipients in formulations and suggest that other proteins may have similar potential.
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Affiliation(s)
- Samantha Piszkiewicz
- Department of Chemistry, University of North Carolina, Chapel Hill, North Carolina, 27599
| | - Kathryn H Gunn
- Department of Biochemistry and Biophysics, University of North Carolina, Chapel Hill, North Carolina, 27599
| | - Owen Warmuth
- Department of Chemistry, University of North Carolina, Chapel Hill, North Carolina, 27599
| | - Ashlee Propst
- Department of Chemistry, University of North Carolina, Chapel Hill, North Carolina, 27599
| | - Aakash Mehta
- Department of Chemistry, University of North Carolina, Chapel Hill, North Carolina, 27599
| | - Kenny H Nguyen
- Department of Chemistry, University of North Carolina, Chapel Hill, North Carolina, 27599
| | - Elizabeth Kuhlman
- Department of Biochemistry and Biophysics, University of North Carolina, Chapel Hill, North Carolina, 27599
| | - Alex J Guseman
- Department of Chemistry, University of North Carolina, Chapel Hill, North Carolina, 27599
| | - Samantha S Stadmiller
- Department of Chemistry, University of North Carolina, Chapel Hill, North Carolina, 27599
| | - Thomas C Boothby
- Department of Chemistry, University of North Carolina, Chapel Hill, North Carolina, 27599
| | - Saskia B Neher
- Department of Biochemistry and Biophysics, University of North Carolina, Chapel Hill, North Carolina, 27599
| | - Gary J Pielak
- Department of Chemistry, University of North Carolina, Chapel Hill, North Carolina, 27599.,Department of Biochemistry and Biophysics, University of North Carolina, Chapel Hill, North Carolina, 27599.,Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, North Carolina, 27599.,Integrative Program for Biological and Genome Sciences, University of North Carolina, Chapel Hill, North Carolina, 27599
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49
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Abstract
A fundamental tenet of multicellular eukaryotic evolution is that vertical inheritance is paramount, with natural selection acting on genetic variants transferred from parents to offspring. This lineal process means that an organism's adaptive potential can be restricted by its evolutionary history, the amount of standing genetic variation, and its mutation rate. Lateral gene transfer (LGT) theoretically provides a mechanism to bypass many of these limitations, but the evolutionary importance and frequency of this process in multicellular eukaryotes, such as plants, remains debated. We address this issue by assembling a chromosome-level genome for the grass Alloteropsis semialata, a species surmised to exhibit two LGTs, and screen it for other grass-to-grass LGTs using genomic data from 146 other grass species. Through stringent phylogenomic analyses, we discovered 57 additional LGTs in the A. semialata nuclear genome, involving at least nine different donor species. The LGTs are clustered in 23 laterally acquired genomic fragments that are up to 170 kb long and have accumulated during the diversification of Alloteropsis. The majority of the 59 LGTs in A. semialata are expressed, and we show that they have added functions to the recipient genome. Functional LGTs were further detected in the genomes of five other grass species, demonstrating that this process is likely widespread in this globally important group of plants. LGT therefore appears to represent a potent evolutionary force capable of spreading functional genes among distantly related grass species.
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50
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