1
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Baum B, Spang A. On the origin of the nucleus: a hypothesis. Microbiol Mol Biol Rev 2023; 87:e0018621. [PMID: 38018971 PMCID: PMC10732040 DOI: 10.1128/mmbr.00186-21] [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] [Indexed: 11/30/2023] Open
Abstract
SUMMARYIn this hypothesis article, we explore the origin of the eukaryotic nucleus. In doing so, we first look afresh at the nature of this defining feature of the eukaryotic cell and its core functions-emphasizing the utility of seeing the eukaryotic nucleoplasm and cytoplasm as distinct regions of a common compartment. We then discuss recent progress in understanding the evolution of the eukaryotic cell from archaeal and bacterial ancestors, focusing on phylogenetic and experimental data which have revealed that many eukaryotic machines with nuclear activities have archaeal counterparts. In addition, we review the literature describing the cell biology of representatives of the TACK and Asgardarchaeaota - the closest known living archaeal relatives of eukaryotes. Finally, bringing these strands together, we propose a model for the archaeal origin of the nucleus that explains much of the current data, including predictions that can be used to put the model to the test.
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Affiliation(s)
- Buzz Baum
- MRC Laboratory of Molecular Biology, Cambridge Biomedical Campus, Cambridge, United Kingdom
| | - Anja Spang
- Department of Marine Microbiology and Biogeochemistry, NIOZ, Royal Netherlands Institute for Sea Research, Den Burg, the Netherlands
- Department of Evolutionary & Population Biology, Institute for Biodiversity and Ecosystem Dynamics (IBED), University of Amsterdam, Amsterdam, the Netherlands
- Department of Marine Microbiology and Biogeochemistry, NIOZ, Royal Netherlands Institute for Sea Research, Den Burg, the Netherlands
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2
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Kapli P, Kotari I, Telford MJ, Goldman N, Yang Z. DNA Sequences Are as Useful as Protein Sequences for Inferring Deep Phylogenies. Syst Biol 2023; 72:1119-1135. [PMID: 37366056 PMCID: PMC10627555 DOI: 10.1093/sysbio/syad036] [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: 02/08/2022] [Indexed: 06/28/2023] Open
Abstract
Inference of deep phylogenies has almost exclusively used protein rather than DNA sequences based on the perception that protein sequences are less prone to homoplasy and saturation or to issues of compositional heterogeneity than DNA sequences. Here, we analyze a model of codon evolution under an idealized genetic code and demonstrate that those perceptions may be misconceptions. We conduct a simulation study to assess the utility of protein versus DNA sequences for inferring deep phylogenies, with protein-coding data generated under models of heterogeneous substitution processes across sites in the sequence and among lineages on the tree, and then analyzed using nucleotide, amino acid, and codon models. Analysis of DNA sequences under nucleotide-substitution models (possibly with the third codon positions excluded) recovered the correct tree at least as often as analysis of the corresponding protein sequences under modern amino acid models. We also applied the different data-analysis strategies to an empirical dataset to infer the metazoan phylogeny. Our results from both simulated and real data suggest that DNA sequences may be as useful as proteins for inferring deep phylogenies and should not be excluded from such analyses. Analysis of DNA data under nucleotide models has a major computational advantage over protein-data analysis, potentially making it feasible to use advanced models that account for among-site and among-lineage heterogeneity in the nucleotide-substitution process in inference of deep phylogenies.
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Affiliation(s)
- Paschalia Kapli
- Department of Genetics, University College London, Gower Street, London WC1E 6BT, UK
| | - Ioanna Kotari
- Department of Genetics, University College London, Gower Street, London WC1E 6BT, UK
- Institut für Populationsgenetik, Vetmeduni Vienna, Vienna, 1210, Austria
| | - Maximilian J Telford
- Department of Genetics, University College London, Gower Street, London WC1E 6BT, UK
| | - Nick Goldman
- European Molecular Biology Laboratory - European Bioinformatics Institute, Wellcome Genome Campus, Hinxton, Cambridge CB10 1SD, UK
| | - Ziheng Yang
- Department of Genetics, University College London, Gower Street, London WC1E 6BT, UK
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3
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Fleming JF, Valero‐Gracia A, Struck TH. Identifying and addressing methodological incongruence in phylogenomics: A review. Evol Appl 2023; 16:1087-1104. [PMID: 37360032 PMCID: PMC10286231 DOI: 10.1111/eva.13565] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2022] [Revised: 04/07/2023] [Accepted: 05/17/2023] [Indexed: 06/28/2023] Open
Abstract
The availability of phylogenetic data has greatly expanded in recent years. As a result, a new era in phylogenetic analysis is dawning-one in which the methods we use to analyse and assess our data are the bottleneck to producing valuable phylogenetic hypotheses, rather than the need to acquire more data. This makes the ability to accurately appraise and evaluate new methods of phylogenetic analysis and phylogenetic artefact identification more important than ever. Incongruence in phylogenetic reconstructions based on different datasets may be due to two major sources: biological and methodological. Biological sources comprise processes like horizontal gene transfer, hybridization and incomplete lineage sorting, while methodological ones contain falsely assigned data or violations of the assumptions of the underlying model. While the former provides interesting insights into the evolutionary history of the investigated groups, the latter should be avoided or minimized as best as possible. However, errors introduced by methodology must first be excluded or minimized to be able to conclude that biological sources are the cause. Fortunately, a variety of useful tools exist to help detect such misassignments and model violations and to apply ameliorating measurements. Still, the number of methods and their theoretical underpinning can be overwhelming and opaque. Here, we present a practical and comprehensive review of recent developments in techniques to detect artefacts arising from model violations and poorly assigned data. The advantages and disadvantages of the different methods to detect such misleading signals in phylogenetic reconstructions are also discussed. As there is no one-size-fits-all solution, this review can serve as a guide in choosing the most appropriate detection methods depending on both the actual dataset and the computational power available to the researcher. Ultimately, this informed selection will have a positive impact on the broader field, allowing us to better understand the evolutionary history of the group of interest.
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4
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Spang A. Is an archaeon the ancestor of eukaryotes? Environ Microbiol 2022; 25:775-779. [PMID: 36562617 DOI: 10.1111/1462-2920.16323] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Accepted: 12/21/2022] [Indexed: 12/24/2022]
Abstract
The origin of complex cellular life is a key puzzle in evolutionary research, which has broad implications for various neighbouring scientific disciplines. Naturally, views on this topic vary widely depending on the world view and context from which this topic is approached. In the following, I will share my perspective about our current scientific knowledge on the origin of eukaryotic cells, that is, eukaryogenesis, from a biological point of view focusing on the question as to whether an archaeon was the ancestor of eukaryotes.
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Affiliation(s)
- Anja Spang
- NIOZ, Royal Netherlands Institute for Sea Research, Department of Marine Microbiology and Biogeochemistry, Utrecht University, AB Den Burg, The Netherlands.,Department of Evolutionary & Population Biology, Institute for Biodiversity and Ecosystem Dynamics (IBED), University of Amsterdam, Amsterdam, The Netherlands
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5
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Lozano-Fernandez J. A Practical Guide to Design and Assess a Phylogenomic Study. Genome Biol Evol 2022; 14:evac129. [PMID: 35946263 PMCID: PMC9452790 DOI: 10.1093/gbe/evac129] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/03/2022] [Indexed: 11/13/2022] Open
Abstract
Over the last decade, molecular systematics has undergone a change of paradigm as high-throughput sequencing now makes it possible to reconstruct evolutionary relationships using genome-scale datasets. The advent of "big data" molecular phylogenetics provided a battery of new tools for biologists but simultaneously brought new methodological challenges. The increase in analytical complexity comes at the price of highly specific training in computational biology and molecular phylogenetics, resulting very often in a polarized accumulation of knowledge (technical on one side and biological on the other). Interpreting the robustness of genome-scale phylogenetic studies is not straightforward, particularly as new methodological developments have consistently shown that the general belief of "more genes, more robustness" often does not apply, and because there is a range of systematic errors that plague phylogenomic investigations. This is particularly problematic because phylogenomic studies are highly heterogeneous in their methodology, and best practices are often not clearly defined. The main aim of this article is to present what I consider as the ten most important points to take into consideration when planning a well-thought-out phylogenomic study and while evaluating the quality of published papers. The goal is to provide a practical step-by-step guide that can be easily followed by nonexperts and phylogenomic novices in order to assess the technical robustness of phylogenomic studies or improve the experimental design of a project.
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Affiliation(s)
- Jesus Lozano-Fernandez
- Department of Genetics, Microbiology and Statistics, Biodiversity Research Institute (IRBio), University of Barcelona, Avd. Diagonal 643, 08028 Barcelona, Spain
- Institute of Evolutionary Biology (CSIC – Universitat Pompeu Fabra), Passeig marítim de la Barcelona 37-49, 08003 Barcelona, Spain
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6
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Aouad M, Flandrois JP, Jauffrit F, Gouy M, Gribaldo S, Brochier-Armanet C. A divide-and-conquer phylogenomic approach based on character supermatrices resolves early steps in the evolution of the Archaea. BMC Ecol Evol 2022; 22:1. [PMID: 34986784 PMCID: PMC8734073 DOI: 10.1186/s12862-021-01952-0] [Citation(s) in RCA: 22] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2021] [Accepted: 11/22/2021] [Indexed: 11/28/2022] Open
Abstract
Background The recent rise in cultivation-independent genome sequencing has provided key material to explore uncharted branches of the Tree of Life. This has been particularly spectacular concerning the Archaea, projecting them at the center stage as prominently relevant to understand early stages in evolution and the emergence of fundamental metabolisms as well as the origin of eukaryotes. Yet, resolving deep divergences remains a challenging task due to well-known tree-reconstruction artefacts and biases in extracting robust ancient phylogenetic signal, notably when analyzing data sets including the three Domains of Life. Among the various strategies aimed at mitigating these problems, divide-and-conquer approaches remain poorly explored, and have been primarily based on reconciliation among single gene trees which however notoriously lack ancient phylogenetic signal. Results We analyzed sub-sets of full supermatrices covering the whole Tree of Life with specific taxonomic sampling to robustly resolve different parts of the archaeal phylogeny in light of their current diversity. Our results strongly support the existence and early emergence of two main clades, Cluster I and Cluster II, which we name Ouranosarchaea and Gaiarchaea, and we clarify the placement of important novel archaeal lineages within these two clades. However, the monophyly and branching of the fast evolving nanosized DPANN members remains unclear and worth of further study. Conclusions We inferred a well resolved rooted phylogeny of the Archaea that includes all recently described phyla of high taxonomic rank. This phylogeny represents a valuable reference to study the evolutionary events associated to the early steps of the diversification of the archaeal domain. Beyond the specifics of archaeal phylogeny, our results demonstrate the power of divide-and-conquer approaches to resolve deep phylogenetic relationships, which should be applied to progressively resolve the entire Tree of Life. Supplementary Information The online version contains supplementary material available at 10.1186/s12862-021-01952-0.
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Affiliation(s)
- Monique Aouad
- Université de Lyon, Université Lyon 1, CNRS, UMR5558, Laboratoire de Biométrie et Biologie Évolutive, 43 bd du 11 novembre 1918, 69622, Villeurbanne, France.,École Supérieure de Biologie-Biochimie-Biotechnologies, Université Catholique de Lyon, 10 place des archives, 69002, Lyon, France
| | - Jean-Pierre Flandrois
- Université de Lyon, Université Lyon 1, CNRS, UMR5558, Laboratoire de Biométrie et Biologie Évolutive, 43 bd du 11 novembre 1918, 69622, Villeurbanne, France
| | - Frédéric Jauffrit
- Université de Lyon, Université Lyon 1, CNRS, UMR5558, Laboratoire de Biométrie et Biologie Évolutive, 43 bd du 11 novembre 1918, 69622, Villeurbanne, France.,Technology Research Department, Innovation Unit, bioMérieux SA, Marcy Étoile, France
| | - Manolo Gouy
- Université de Lyon, Université Lyon 1, CNRS, UMR5558, Laboratoire de Biométrie et Biologie Évolutive, 43 bd du 11 novembre 1918, 69622, Villeurbanne, France
| | - Simonetta Gribaldo
- Department of Microbiology, Unit "Evolutionary Biology of the Microbial Cell", UMR2001, Institut Pasteur, Paris, France.
| | - Céline Brochier-Armanet
- Université de Lyon, Université Lyon 1, CNRS, UMR5558, Laboratoire de Biométrie et Biologie Évolutive, 43 bd du 11 novembre 1918, 69622, Villeurbanne, France.
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7
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Foster PG. Phylogenetic Analysis That Models Compositional Heterogeneity over the Tree. Methods Mol Biol 2022; 2569:119-135. [PMID: 36083446 DOI: 10.1007/978-1-0716-2691-7_6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Molecular sequences in a phylogenetic analysis can differ in composition, and that shows that the process of evolution can change over time. However, models of evolution in common use are homogeneous over the tree, and if used in a phylogenetic analysis with compositionally tree-heterogeneous datasets these models can recover incorrect trees. The NDCH or Node-Discrete Compositional Heterogeneity model is able to model such data by accommodating differences in composition over the tree. Usage, problems, and limitations of this model are discussed, and a modification, the NDCH2 model, is described that can ameliorate some of these problems and limitations. Using these models can greatly increase the fit of the model to the data and can find better tree topologies. These models and various statistical tests are illustrated using a bacterial SSU rRNA dataset. These models are implemented in the software P4, and files for the analyses described here are made available.
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Affiliation(s)
- Peter G Foster
- Department of Life Sciences, Natural History Museum, London, UK
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8
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Vankan M, Ho SYW, Duchêne DA. Evolutionary Rate Variation Among Lineages in Gene Trees has a Negative Impact on Species-Tree Inference. Syst Biol 2021; 71:490-500. [PMID: 34255084 PMCID: PMC8830059 DOI: 10.1093/sysbio/syab051] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Revised: 06/18/2021] [Indexed: 11/12/2022] Open
Abstract
Phylogenetic analyses of genomic data provide a powerful means of reconstructing the evolutionary relationships among organisms, yet such analyses are often hindered by conflicting phylogenetic signals among loci. Identifying the signals that are most influential to species-tree estimation can help to inform the choice of data for phylogenomic analysis. We investigated this in an analysis of 30 phylogenomic data sets. For each data set, we examined the association between several branch-length characteristics of gene trees and the distance between these gene trees and the corresponding species trees. We found that the distance of each gene tree to the species tree inferred from the full data set was positively associated with variation in root-to-tip distances and negatively associated with mean branch support. However, no such associations were found for gene-tree length, a measure of the overall substitution rate at each locus. We further explored the usefulness of the best-performing branch-based characteristics for selecting loci for phylogenomic analyses. We found that loci that yield gene trees with high variation in root-to-tip distances have a disproportionately distant signal of tree topology compared with the complete data sets. These results suggest that rate variation across lineages should be taken into consideration when exploring and even selecting loci for phylogenomic analysis.[Branch support; data filtering; nucleotide substitution model; phylogenomics; substitution rate; summary coalescent methods.]
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Affiliation(s)
- Mezzalina Vankan
- School of Life and Environmental Sciences, University of Sydney, NSW 2006, Australia.,Research School of Biology, Australian National University, ACT 2601, Australia
| | - Simon Y W Ho
- School of Life and Environmental Sciences, University of Sydney, NSW 2006, Australia
| | - David A Duchêne
- Research School of Biology, Australian National University, ACT 2601, Australia.,Centre for Evolutionary Hologenomics, University of Copenhagen, Copenhagen 1352, Denmark
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9
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Hernandez AM, Ryan JF. Six-state Amino Acid Recoding is not an Effective Strategy to Offset Compositional Heterogeneity and Saturation in Phylogenetic Analyses. Syst Biol 2021; 70:1200-1212. [PMID: 33837789 PMCID: PMC8513762 DOI: 10.1093/sysbio/syab027] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2019] [Revised: 04/02/2021] [Accepted: 04/05/2021] [Indexed: 01/25/2023] Open
Abstract
Six-state amino acid recoding strategies are commonly applied to combat the effects of compositional heterogeneity and substitution saturation in phylogenetic analyses. While these methods have been endorsed from a theoretical perspective, their performance has never been extensively tested. Here, we test the effectiveness of six-state recoding approaches by comparing the performance of analyses on recoded and non-recoded data sets that have been simulated under gradients of compositional heterogeneity or saturation. In our simulation analyses, non-recoding approaches consistently outperform six-state recoding approaches. Our results suggest that six-state recoding strategies are not effective in the face of high saturation. Furthermore, while recoding strategies do buffer the effects of compositional heterogeneity, the loss of information that accompanies six-state recoding outweighs its benefits. In addition, we evaluate recoding schemes with 9, 12, 15, and 18 states and show that these consistently outperform six-state recoding. Our analyses of other recoding schemes suggest that under conditions of very high compositional heterogeneity, it may be advantageous to apply recoding using more than six states, but we caution that applying any recoding should include sufficient justification. Our results have important implications for the more than 90 published papers that have incorporated six-state recoding, many of which have significant bearing on relationships across the tree of life. [Compositional heterogeneity; Dayhoff 6-state recoding; S&R 6-state recoding; six-state amino acid recoding; substitution saturation.]
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Affiliation(s)
- Alexandra M Hernandez
- Whitney Laboratory for Marine Bioscience, 9505 Ocean Shore Boulevard, St. Augustine, FL, 32080, USA.,Department of Biology, University of Florida, 220 Bartram Hall, P.O. Box 118525, Gainesville, FL, 32611, USA
| | - Joseph F Ryan
- Whitney Laboratory for Marine Bioscience, 9505 Ocean Shore Boulevard, St. Augustine, FL, 32080, USA.,Department of Biology, University of Florida, 220 Bartram Hall, P.O. Box 118525, Gainesville, FL, 32611, USA
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10
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Williams TA, Schrempf D, Szöllősi GJ, Cox CJ, Foster PG, Embley TM. Inferring the deep past from molecular data. Genome Biol Evol 2021; 13:6192802. [PMID: 33772552 PMCID: PMC8175050 DOI: 10.1093/gbe/evab067] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/22/2021] [Indexed: 12/17/2022] Open
Abstract
There is an expectation that analyses of molecular sequences might be able to distinguish between alternative hypotheses for ancient relationships, but the phylogenetic methods used and types of data analyzed are of critical importance in any attempt to recover historical signal. Here, we discuss some common issues that can influence the topology of trees obtained when using overly simple models to analyze molecular data that often display complicated patterns of sequence heterogeneity. To illustrate our discussion, we have used three examples of inferred relationships which have changed radically as models and methods of analysis have improved. In two of these examples, the sister-group relationship between thermophilic Thermus and mesophilic Deinococcus, and the position of long-branch Microsporidia among eukaryotes, we show that recovering what is now generally considered to be the correct tree is critically dependent on the fit between model and data. In the third example, the position of eukaryotes in the tree of life, the hypothesis that is currently supported by the best available methods is fundamentally different from the classical view of relationships between major cellular domains. Since heterogeneity appears to be pervasive and varied among all molecular sequence data, and even the best available models can still struggle to deal with some problems, the issues we discuss are generally relevant to phylogenetic analyses. It remains essential to maintain a critical attitude to all trees as hypotheses of relationship that may change with more data and better methods.
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Affiliation(s)
- Tom A Williams
- School of Biological Sciences, University of Bristol, Bristol BS8 1TQ, United Kingdom
| | - Dominik Schrempf
- Dept. of Biological Physics, Eötvös Loránd University, 1117 Budapest, Hungary
| | - Gergely J Szöllősi
- Dept. of Biological Physics, Eötvös Loránd University, 1117 Budapest, Hungary.,MTA-ELTE "Lendület" Evolutionary Genomics Research Group, 1117 Budapest, Hungary.,Institute of Evolution, Centre for Ecological Research, 1121 Budapest, Hungary
| | - Cymon J Cox
- Centro de Ciências do Mar, Universidade do Algarve, Gambelas, 8005-319 Faro, Portugal
| | - Peter G Foster
- Department of Life Sciences, Natural History Museum, London SW7 5BD, United Kingdom
| | - T Martin Embley
- Biosciences Institute, Centre for Bacterial Cell Biology, Newcastle University, Newcastle upon Tyne NE2 4AX, United Kingdom
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11
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Abstract
Phagocytosis, or 'cell eating', is a eukaryote-specific process where particulate matter is engulfed via invaginations of the plasma membrane. The origin of phagocytosis has been central to discussions on eukaryogenesis for decades-, where it is argued as being either a prerequisite for, or consequence of, the acquisition of the ancestral mitochondrion. Recently, genomic and cytological evidence has increasingly supported the view that the pre-mitochondrial host cell-a bona fide archaeon branching within the 'Asgard' archaea-was incapable of phagocytosis and used alternative mechanisms to incorporate the alphaproteobacterial ancestor of mitochondria. Indeed, the diversity and variability of proteins associated with phagosomes across the eukaryotic tree suggest that phagocytosis, as seen in a variety of extant eukaryotes, may have evolved independently several times within the eukaryotic crown-group. Since phagocytosis is critical to the functioning of modern marine food webs (without it, there would be no microbial loop or animal life), multiple late origins of phagocytosis could help explain why many of the ecological and evolutionary innovations of the Neoproterozoic Era (e.g. the advent of eukaryotic biomineralization, the 'Rise of Algae' and the origin of animals) happened when they did.
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Affiliation(s)
- Daniel B. Mills
- Department of Geological Sciences, Stanford University, Stanford, CA 94305, USA
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12
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Abstract
That Bacteria, Archaea and Eukarya (eukaryotes) represent three separate domains of Life, no one having evolved from within any other, has been taken as fact for three decades. Recent work shows this to be untrue. Eukarya arose from well within Archaea and are specifically related to newly discovered archaeal species with eukaryote-like features.
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Affiliation(s)
- W Ford Doolittle
- Department of Biochemistry and Molecular Biology, Dalhousie University, Halifax, Nova Scotia B3H 4R2, Canada.
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13
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Sousa F, Civáň P, Foster PG, Cox CJ. The Chloroplast Land Plant Phylogeny: Analyses Employing Better-Fitting Tree- and Site-Heterogeneous Composition Models. FRONTIERS IN PLANT SCIENCE 2020; 11:1062. [PMID: 32760416 PMCID: PMC7373204 DOI: 10.3389/fpls.2020.01062] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Accepted: 06/26/2020] [Indexed: 05/02/2023]
Abstract
The colonization of land by descendants of charophyte green algae marked a turning point in Earth history that enabled the development of the diverse terrestrial ecosystems we see today. Early land plants diversified into three gametophyte-dominant lineages, namely the hornworts, liverworts, and mosses, collectively known as bryophytes, and a sporophyte-dominant lineage, the vascular plants, or tracheophytes. In recent decades, the prevailing view of evolutionary relationships among these four lineages has been that the tracheophytes were derived from a bryophyte ancestor. However, recent phylogenetic evidence has suggested that bryophytes are monophyletic, and thus that the first split among land plants gave rise to the lineages that today we recognize as the bryophytes and tracheophytes. We present a phylogenetic analysis of chloroplast protein-coding data that also supports the monophyly of bryophytes. This newly compiled data set consists of 83 chloroplast genes sampled across 30 taxa that include chlorophytes and charophytes, including four members of the Zygnematophyceae, and land plants, that were sampled following a balanced representation of the main bryophyte and tracheophyte lineages. Analyses of non-synonymous site nucleotide data and amino acid translation data result in congruent phylogenetic trees showing the monophyly of bryophytes, with the Zygnematophyceae as the charophyte group most closely related to land plants. Analyses showing that bryophytes and tracheophytes evolved separately from a common terrestrial ancestor have profound implications for the way we understand the evolution of plant life cycles on land and how we interpret the early land plant fossil record.
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Affiliation(s)
- Filipe Sousa
- Centro de Ciências do Mar, Universidade do Algarve, Faro, Portugal
| | - Peter Civáň
- Centro de Ciências do Mar, Universidade do Algarve, Faro, Portugal
- INRA, Université Clermont-Auvergne, Clermont-Ferrand, France
| | - Peter G. Foster
- Department of Life Sciences, Natural History Museum, London, United Kingdom
| | - Cymon J. Cox
- Centro de Ciências do Mar, Universidade do Algarve, Faro, Portugal
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14
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Cai C, Tihelka E, Pisani D, Donoghue PCJ. Data curation and modeling of compositional heterogeneity in insect phylogenomics: A case study of the phylogeny of Dytiscoidea (Coleoptera: Adephaga). Mol Phylogenet Evol 2020; 147:106782. [PMID: 32147574 DOI: 10.1016/j.ympev.2020.106782] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2020] [Accepted: 02/26/2020] [Indexed: 10/24/2022]
Abstract
Diving beetles and their allies are an almost ubiquitous group of freshwater predators. Knowledge of the phylogeny of the adephagan superfamily Dytiscoidea has significantly improved since the advent of molecular phylogenetics. However, despite recent comprehensive phylogenomic studies, some phylogenetic relationships among the constituent families remain elusive. In particular, the position of the family Hygrobiidae remains uncertain. We address these issues by re-analyzing recently published phylogenomic datasets for Dytiscoidea, using approaches to reduce compositional heterogeneity and adopting a site-heterogeneous mixture model. We obtained a consistent, well-resolved, and strongly supported tree. Consistent with previous studies, our analyses support Aspidytidae as the monophyletic sister group of Amphizoidae, and more importantly, Hygrobiidae as the sister of the diverse Dytiscidae, in agreement with morphology-based phylogenies. Our analyses provide a backbone phylogeny of Dytiscoidea, which lays the foundation for better understanding the evolution of morphological characters, life habits, and feeding behaviors of dytiscoid beetles.
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Affiliation(s)
- Chenyang Cai
- State Key Laboratory of Palaeobiology and Stratigraphy, Nanjing Institute of Geology and Palaeontology, and Centre for Excellence in Life and Paleoenvironment, Chinese Academy of Sciences, Nanjing 210008, China; School of Earth Sciences, University of Bristol, Life Sciences Building, Tyndall Avenue, Bristol BS8 1TQ, UK.
| | - Erik Tihelka
- Department of Animal Science, Hartpury College, Hartpury GL19 3BE, UK
| | - Davide Pisani
- School of Earth Sciences, University of Bristol, Life Sciences Building, Tyndall Avenue, Bristol BS8 1TQ, UK; School of Biological Sciences, University of Bristol, Life Sciences Building, Tyndall Avenue, Bristol BS8 1TQ, UK
| | - Philip C J Donoghue
- School of Earth Sciences, University of Bristol, Life Sciences Building, Tyndall Avenue, Bristol BS8 1TQ, UK.
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15
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Cavalier-Smith T, Chao EEY. Multidomain ribosomal protein trees and the planctobacterial origin of neomura (eukaryotes, archaebacteria). PROTOPLASMA 2020. [PMID: 31900730 DOI: 10.1007/s00709-019-01442] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
Palaeontologically, eubacteria are > 3× older than neomura (eukaryotes, archaebacteria). Cell biology contrasts ancestral eubacterial murein peptidoglycan walls and derived neomuran N-linked glycoprotein coats/walls. Misinterpreting long stems connecting clade neomura to eubacteria on ribosomal sequence trees (plus misinterpreted protein paralogue trees) obscured this historical pattern. Universal multiprotein ribosomal protein (RP) trees, more accurate than rRNA trees, are taxonomically undersampled. To reduce contradictions with genically richer eukaryote trees and improve eubacterial phylogeny, we constructed site-heterogeneous and maximum-likelihood universal three-domain, two-domain, and single-domain trees for 143 eukaryotes (branching now congruent with 187-protein trees), 60 archaebacteria, and 151 taxonomically representative eubacteria, using 51 and 26 RPs. Site-heterogeneous trees greatly improve eubacterial phylogeny and higher classification, e.g. showing gracilicute monophyly, that many 'rDNA-phyla' belong in Proteobacteria, and reveal robust new phyla Synthermota and Aquithermota. Monoderm Posibacteria and Mollicutes (two separate wall losses) are both polyphyletic: multiple outer membrane losses in Endobacteria occurred separately from Actinobacteria; neither phylum is related to Chloroflexi, the most divergent prokaryotes, which originated photosynthesis (new model proposed). RP trees support an eozoan root for eukaryotes and are consistent with archaebacteria being their sisters and rooted between Filarchaeota (=Proteoarchaeota, including 'Asgardia') and Euryarchaeota sensu-lato (including ultrasimplified 'DPANN' whose long branches often distort trees). Two-domain trees group eukaryotes within Planctobacteria, and archaebacteria with Planctobacteria/Sphingobacteria. Integrated molecular/palaeontological evidence favours negibacterial ancestors for neomura and all life. Unique presence of key pre-neomuran characters favours Planctobacteria only as ancestral to neomura, which apparently arose by coevolutionary repercussions (explained here in detail, including RP replacement) of simultaneous outer membrane and murein loss. Planctobacterial C-1 methanotrophic enzymes are likely ancestral to archaebacterial methanogenesis and β-propeller-α-solenoid proteins to eukaryotic vesicle coats, nuclear-pore-complexes, and intraciliary transport. Planctobacterial chaperone-independent 4/5-protofilament microtubules and MamK actin-ancestors prepared for eukaryote intracellular motility, mitosis, cytokinesis, and phagocytosis. We refute numerous wrong ideas about the universal tree.
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Affiliation(s)
| | - Ema E-Yung Chao
- Department of Zoology, University of Oxford, South Parks Road, Oxford, OX1 3PS, UK
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16
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Cavalier-Smith T, Chao EEY. Multidomain ribosomal protein trees and the planctobacterial origin of neomura (eukaryotes, archaebacteria). PROTOPLASMA 2020; 257:621-753. [PMID: 31900730 PMCID: PMC7203096 DOI: 10.1007/s00709-019-01442-7] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/25/2019] [Accepted: 09/19/2019] [Indexed: 05/02/2023]
Abstract
Palaeontologically, eubacteria are > 3× older than neomura (eukaryotes, archaebacteria). Cell biology contrasts ancestral eubacterial murein peptidoglycan walls and derived neomuran N-linked glycoprotein coats/walls. Misinterpreting long stems connecting clade neomura to eubacteria on ribosomal sequence trees (plus misinterpreted protein paralogue trees) obscured this historical pattern. Universal multiprotein ribosomal protein (RP) trees, more accurate than rRNA trees, are taxonomically undersampled. To reduce contradictions with genically richer eukaryote trees and improve eubacterial phylogeny, we constructed site-heterogeneous and maximum-likelihood universal three-domain, two-domain, and single-domain trees for 143 eukaryotes (branching now congruent with 187-protein trees), 60 archaebacteria, and 151 taxonomically representative eubacteria, using 51 and 26 RPs. Site-heterogeneous trees greatly improve eubacterial phylogeny and higher classification, e.g. showing gracilicute monophyly, that many 'rDNA-phyla' belong in Proteobacteria, and reveal robust new phyla Synthermota and Aquithermota. Monoderm Posibacteria and Mollicutes (two separate wall losses) are both polyphyletic: multiple outer membrane losses in Endobacteria occurred separately from Actinobacteria; neither phylum is related to Chloroflexi, the most divergent prokaryotes, which originated photosynthesis (new model proposed). RP trees support an eozoan root for eukaryotes and are consistent with archaebacteria being their sisters and rooted between Filarchaeota (=Proteoarchaeota, including 'Asgardia') and Euryarchaeota sensu-lato (including ultrasimplified 'DPANN' whose long branches often distort trees). Two-domain trees group eukaryotes within Planctobacteria, and archaebacteria with Planctobacteria/Sphingobacteria. Integrated molecular/palaeontological evidence favours negibacterial ancestors for neomura and all life. Unique presence of key pre-neomuran characters favours Planctobacteria only as ancestral to neomura, which apparently arose by coevolutionary repercussions (explained here in detail, including RP replacement) of simultaneous outer membrane and murein loss. Planctobacterial C-1 methanotrophic enzymes are likely ancestral to archaebacterial methanogenesis and β-propeller-α-solenoid proteins to eukaryotic vesicle coats, nuclear-pore-complexes, and intraciliary transport. Planctobacterial chaperone-independent 4/5-protofilament microtubules and MamK actin-ancestors prepared for eukaryote intracellular motility, mitosis, cytokinesis, and phagocytosis. We refute numerous wrong ideas about the universal tree.
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Affiliation(s)
| | - Ema E-Yung Chao
- Department of Zoology, University of Oxford, South Parks Road, Oxford, OX1 3PS, UK
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17
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Williams TA, Cox CJ, Foster PG, Szöllősi GJ, Embley TM. Phylogenomics provides robust support for a two-domains tree of life. Nat Ecol Evol 2020; 4:138-147. [PMID: 31819234 PMCID: PMC6942926 DOI: 10.1038/s41559-019-1040-x] [Citation(s) in RCA: 119] [Impact Index Per Article: 29.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2019] [Accepted: 10/15/2019] [Indexed: 11/09/2022]
Abstract
Hypotheses about the origin of eukaryotic cells are classically framed within the context of a universal 'tree of life' based on conserved core genes. Vigorous ongoing debate about eukaryote origins is based on assertions that the topology of the tree of life depends on the taxa included and the choice and quality of genomic data analysed. Here we have reanalysed the evidence underpinning those claims and apply more data to the question by using supertree and coalescent methods to interrogate >3,000 gene families in archaea and eukaryotes. We find that eukaryotes consistently originate from within the archaea in a two-domains tree when due consideration is given to the fit between model and data. Our analyses support a close relationship between eukaryotes and Asgard archaea and identify the Heimdallarchaeota as the current best candidate for the closest archaeal relatives of the eukaryotic nuclear lineage.
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Affiliation(s)
- Tom A Williams
- School of Biological Sciences, University of Bristol, Bristol, UK.
| | - Cymon J Cox
- Centro de Ciências do Mar, Universidade do Algarve, Faro, Portugal
| | - Peter G Foster
- Department of Life Sciences, Natural History Museum, London, UK
| | - Gergely J Szöllősi
- MTA-ELTE "Lendület" Evolutionary Genomics Research Group, Budapest, Hungary
- Department of Biological Physics, Eötvös Loránd University, Budapest, Hungary
- Evolutionary Systems Research Group, Centre for Ecological Research, Hungarian Academy of Sciences, Tihany, Hungary
| | - T Martin Embley
- Institute for Cell and Molecular Biosciences, University of Newcastle, Newcastle upon Tyne, UK.
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18
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Gribaldo S, Brochier-Armanet C. Evolutionary relationships between Archaea and eukaryotes. Nat Ecol Evol 2019; 4:20-21. [DOI: 10.1038/s41559-019-1073-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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19
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Carr SA, Jungbluth SP, Eloe-Fadrosh EA, Stepanauskas R, Woyke T, Rappé MS, Orcutt BN. Carboxydotrophy potential of uncultivated Hydrothermarchaeota from the subseafloor crustal biosphere. THE ISME JOURNAL 2019; 13:1457-1468. [PMID: 30728468 PMCID: PMC6775978 DOI: 10.1038/s41396-019-0352-9] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/02/2018] [Revised: 12/07/2018] [Accepted: 12/23/2018] [Indexed: 11/08/2022]
Abstract
The exploration of Earth's terrestrial subsurface biosphere has led to the discovery of several new archaeal lineages of evolutionary significance. Similarly, the deep subseafloor crustal biosphere also harbors many unique, uncultured archaeal taxa, including those belonging to Candidatus Hydrothermarchaeota, formerly known as Marine Benthic Group-E. Recently, Hydrothermarchaeota was identified as an abundant lineage of Juan de Fuca Ridge flank crustal fluids, suggesting its adaptation to this extreme environment. Through the investigation of single-cell and metagenome-assembled genomes, we provide insight into the lineage's evolutionary history and metabolic potential. Phylogenomic analysis reveals the Hydrothermarchaeota to be an early-branching archaeal phylum, branching between the superphylum DPANN, Euryarchaeota, and Asgard lineages. Hydrothermarchaeota genomes suggest a potential for dissimilative and assimilative carbon monoxide oxidation (carboxydotrophy), as well as sulfate and nitrate reduction. There is also a prevalence of chemotaxis and motility genes, indicating adaptive strategies for this nutrient-limited fluid-rock environment. These findings provide the first genomic interpretations of the Hydrothermarchaeota phylum and highlight the anoxic, hot, deep marine crustal biosphere as an important habitat for understanding the evolution of early life.
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Affiliation(s)
- Stephanie A Carr
- Bigelow Laboratory for Ocean Sciences, 60 Bigelow Drive, East Boothbay, ME, 04544, USA
- Hartwick College, Oneonta, NY, USA
| | - Sean P Jungbluth
- Center for Dark Energy Biosphere Investigations, University of Southern California, Los Angeles, CA, USA
- Department of Energy, Joint Genome Institute, Walnut Creek, CA, USA
- Hawaii Institute of Marine Biology, University of Hawaii at Manoa, PO BOX 1346, Kaneohe, HI, 96744, USA
| | | | - Ramunas Stepanauskas
- Bigelow Laboratory for Ocean Sciences, 60 Bigelow Drive, East Boothbay, ME, 04544, USA
| | - Tanja Woyke
- Department of Energy, Joint Genome Institute, Walnut Creek, CA, USA
| | - Michael S Rappé
- Hawaii Institute of Marine Biology, University of Hawaii at Manoa, PO BOX 1346, Kaneohe, HI, 96744, USA.
| | - Beth N Orcutt
- Bigelow Laboratory for Ocean Sciences, 60 Bigelow Drive, East Boothbay, ME, 04544, USA.
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20
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de Sousa F, Foster PG, Donoghue PCJ, Schneider H, Cox CJ. Nuclear protein phylogenies support the monophyly of the three bryophyte groups (Bryophyta Schimp.). THE NEW PHYTOLOGIST 2019; 222:565-575. [PMID: 30411803 DOI: 10.1111/nph.15587] [Citation(s) in RCA: 56] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/21/2018] [Accepted: 10/31/2018] [Indexed: 05/05/2023]
Abstract
Unraveling the phylogenetic relationships between the four major lineages of terrestrial plants (mosses, liverworts, hornworts, and vascular plants) is essential for an understanding of the evolution of traits specific to land plants, such as their complex life cycles, and the evolutionary development of stomata and vascular tissue. Well supported phylogenetic hypotheses resulting from different data and methods are often incongruent due to processes of nucleotide evolution that are difficult to model, for example substitutional saturation and composition heterogeneity. We reanalysed a large published dataset of nuclear data and modelled these processes using degenerate-codon recoding and tree-heterogeneous composition substitution models. Our analyses resolved bryophytes as a monophyletic group and showed that the nonnonmonophyly of the clade that is supported by the analysis of nuclear nucleotide data is due solely to fast-evolving synonymous substitutions. The current congruence among phylogenies of both nuclear and chloroplast analyses lent considerable support to the conclusion that the bryophytes are a monophyletic group. An initial split between bryophytes and vascular plants implies that the bryophyte life cycle (with a dominant gametophyte nurturing an unbranched sporophyte) may not be ancestral to all land plants and that stomata are likely to be a symplesiomorphy among embryophytes.
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Affiliation(s)
- Filipe de Sousa
- Centro de Ciências do Mar, Universidade do Algarve, Gambelas, Faro, 8005-319, Portugal
| | - Peter G Foster
- Department of Life Sciences, Natural History Museum, London, SW7 5BD, UK
| | | | - Harald Schneider
- Department of Life Sciences, Natural History Museum, London, SW7 5BD, UK
- School of Earth Sciences, University of Bristol, Bristol, BS8 1TQ, UK
- Center of Integrative Conservation, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Yunnan, 666303, China
| | - Cymon J Cox
- Centro de Ciências do Mar, Universidade do Algarve, Gambelas, Faro, 8005-319, Portugal
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21
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An evolving view of methane metabolism in the Archaea. Nat Rev Microbiol 2019; 17:219-232. [DOI: 10.1038/s41579-018-0136-7] [Citation(s) in RCA: 231] [Impact Index Per Article: 46.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2017] [Accepted: 11/26/2018] [Indexed: 11/08/2022]
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22
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Harish A. What is an archaeon and are the Archaea really unique? PeerJ 2018; 6:e5770. [PMID: 30357005 PMCID: PMC6196074 DOI: 10.7717/peerj.5770] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2018] [Accepted: 09/05/2018] [Indexed: 12/05/2022] Open
Abstract
The recognition of the group Archaea as a major branch of the tree of life (ToL) prompted a new view of the evolution of biodiversity. The genomic representation of archaeal biodiversity has since significantly increased. In addition, advances in phylogenetic modeling of multi-locus datasets have resolved many recalcitrant branches of the ToL. Despite the technical advances and an expanded taxonomic representation, two important aspects of the origins and evolution of the Archaea remain controversial, even as we celebrate the 40th anniversary of the monumental discovery. These issues concern (i) the uniqueness (monophyly) of the Archaea, and (ii) the evolutionary relationships of the Archaea to the Bacteria and the Eukarya; both of these are relevant to the deep structure of the ToL. To explore the causes for this persistent ambiguity, I examine multiple datasets and different phylogenetic approaches that support contradicting conclusions. I find that the uncertainty is primarily due to a scarcity of information in standard datasets-universal core-genes datasets-to reliably resolve the conflicts. These conflicts can be resolved efficiently by comparing patterns of variation in the distribution of functional genomic signatures, which are less diffused unlike patterns of primary sequence variation. Relatively lower heterogeneity in distribution patterns minimizes uncertainties and supports statistically robust phylogenetic inferences, especially of the earliest divergences of life. This case study further highlights the limitations of primary sequence data in resolving difficult phylogenetic problems, and raises questions about evolutionary inferences drawn from the analyses of sequence alignments of a small set of core genes. In particular, the findings of this study corroborate the growing consensus that reversible substitution mutations may not be optimal phylogenetic markers for resolving early divergences in the ToL, nor for determining the polarity of evolutionary transitions across the ToL.
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Affiliation(s)
- Ajith Harish
- Department of Cell and Molecular Biology, Program in Molecular Biology, Uppsala University, Uppsala, Sweden
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23
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A Shepherd D, Klaere S. How Well Does Your Phylogenetic Model Fit Your Data? Syst Biol 2018; 68:157-167. [DOI: 10.1093/sysbio/syy066] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2016] [Accepted: 10/11/2018] [Indexed: 12/27/2022] Open
Affiliation(s)
- Daisy A Shepherd
- Department of Statistics, The University of Auckland, Auckland, New Zealand
| | - Steffen Klaere
- Department of Statistics, The University of Auckland, Auckland, New Zealand
- School of Biological Sciences, The University of Auckland, Auckland, New Zealand
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24
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Cherlin S, Heaps SE, Nye TMW, Boys RJ, Williams TA, Embley TM. The Effect of Nonreversibility on Inferring Rooted Phylogenies. Mol Biol Evol 2018; 35:984-1002. [PMID: 29149300 PMCID: PMC5889004 DOI: 10.1093/molbev/msx294] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Most phylogenetic models assume that the evolutionary process is stationary and reversible. In addition to being biologically improbable, these assumptions also impair inference by generating models under which the likelihood does not depend on the position of the root. Consequently, the root of the tree cannot be inferred as part of the analysis. Yet identifying the root position is a key component of phylogenetic inference because it provides a point of reference for polarizing ancestor-descendant relationships and therefore interpreting the tree. In this paper, we investigate the effect of relaxing the unrealistic reversibility assumption and allowing the position of the root to be another unknown. We propose two hierarchical models that are centered on a reversible model but perturbed to allow nonreversibility. The models differ in the degree of structure imposed on the perturbations. The analysis is performed in the Bayesian framework using Markov chain Monte Carlo methods for which software is provided. We illustrate the performance of the two nonreversible models in analyses of simulated data using two types of topological priors. We then apply the models to a real biological data set, the radiation of polyploid yeasts, for which there is robust biological opinion about the root position. Finally, we apply the models to a second biological alignment for which the rooted tree is controversial: the ribosomal tree of life. We compare the two nonreversible models and conclude that both are useful in inferring the position of the root from real biological data.
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Affiliation(s)
- Svetlana Cherlin
- Institute of Genetic Medicine, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Sarah E Heaps
- School of Mathematics, Statistics and Physics, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Tom M W Nye
- School of Mathematics, Statistics and Physics, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Richard J Boys
- School of Mathematics, Statistics and Physics, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Tom A Williams
- School of Biological Sciences, University of Bristol, Bristol, United Kingdom
| | - T Martin Embley
- Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle upon Tyne, United Kingdom
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25
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Spang A, Eme L, Saw JH, Caceres EF, Zaremba-Niedzwiedzka K, Lombard J, Guy L, Ettema TJG. Asgard archaea are the closest prokaryotic relatives of eukaryotes. PLoS Genet 2018; 14:e1007080. [PMID: 29596421 PMCID: PMC5875740 DOI: 10.1371/journal.pgen.1007080] [Citation(s) in RCA: 85] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2017] [Accepted: 10/17/2017] [Indexed: 11/18/2022] Open
Affiliation(s)
- Anja Spang
- Department of Cell and Molecular Biology, Science for Life Laboratory, Uppsala University, Uppsala, Sweden
| | - Laura Eme
- Department of Cell and Molecular Biology, Science for Life Laboratory, Uppsala University, Uppsala, Sweden
| | - Jimmy H Saw
- Department of Microbiology, Oregon State University, Corvallis, Oregon, United States of America
| | - Eva F Caceres
- Department of Cell and Molecular Biology, Science for Life Laboratory, Uppsala University, Uppsala, Sweden
| | | | - Jonathan Lombard
- Department of Cell and Molecular Biology, Science for Life Laboratory, Uppsala University, Uppsala, Sweden
| | - Lionel Guy
- Department of Medical Biochemistry and Microbiology, Uppsala University, Uppsala, Sweden
| | - Thijs J G Ettema
- Department of Cell and Molecular Biology, Science for Life Laboratory, Uppsala University, Uppsala, Sweden
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26
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Leger MM, Eme L, Stairs CW, Roger AJ. Demystifying Eukaryote Lateral Gene Transfer (Response to Martin 2017 DOI: 10.1002/bies.201700115). Bioessays 2018; 40:e1700242. [DOI: 10.1002/bies.201700242] [Citation(s) in RCA: 54] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2017] [Revised: 02/06/2018] [Indexed: 12/28/2022]
Affiliation(s)
- Michelle M. Leger
- Institute of Evolutionary Biology (CSIC-UPF); Pg. Marítim de la Barceloneta, Barcelona ES 08003 Spain
| | - Laura Eme
- Department of Cell and Molecular Biology; Science for Life Laboratory; Uppsala University; Box 596, Uppsala SE 751 25 Sweden
| | - Courtney W. Stairs
- Department of Cell and Molecular Biology; Science for Life Laboratory; Uppsala University; Box 596, Uppsala SE 751 25 Sweden
| | - Andrew J. Roger
- Centre for Comparative Genomics and Evolutionary Bioinformatics; Department of Biochemistry and Molecular Biology; Dalhousie University; P.O. Box 15000, Halifax CAN B3H 4R2 Nova Scotia Canada
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27
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Eiserhardt WL, Antonelli A, Bennett DJ, Botigué LR, Burleigh JG, Dodsworth S, Enquist BJ, Forest F, Kim JT, Kozlov AM, Leitch IJ, Maitner BS, Mirarab S, Piel WH, Pérez-Escobar OA, Pokorny L, Rahbek C, Sandel B, Smith SA, Stamatakis A, Vos RA, Warnow T, Baker WJ. A roadmap for global synthesis of the plant tree of life. AMERICAN JOURNAL OF BOTANY 2018; 105:614-622. [PMID: 29603138 DOI: 10.1002/ajb2.1041] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2017] [Accepted: 11/08/2017] [Indexed: 06/08/2023]
Abstract
Providing science and society with an integrated, up-to-date, high quality, open, reproducible and sustainable plant tree of life would be a huge service that is now coming within reach. However, synthesizing the growing body of DNA sequence data in the public domain and disseminating the trees to a diverse audience are often not straightforward due to numerous informatics barriers. While big synthetic plant phylogenies are being built, they remain static and become quickly outdated as new data are published and tree-building methods improve. Moreover, the body of existing phylogenetic evidence is hard to navigate and access for non-experts. We propose that our community of botanists, tree builders, and informaticians should converge on a modular framework for data integration and phylogenetic analysis, allowing easy collaboration, updating, data sourcing and flexible analyses. With support from major institutions, this pipeline should be re-run at regular intervals, storing trees and their metadata long-term. Providing the trees to a diverse global audience through user-friendly front ends and application development interfaces should also be a priority. Interactive interfaces could be used to solicit user feedback and thus improve data quality and to coordinate the generation of new data. We conclude by outlining a number of steps that we suggest the scientific community should take to achieve global phylogenetic synthesis.
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Affiliation(s)
- Wolf L Eiserhardt
- Royal Botanic Gardens, Kew, TW9 3AE, Richmond, Surrey, UK
- Department of Bioscience, Aarhus University, Ny Munkegade 116, 8000, Aarhus C, Denmark
| | - Alexandre Antonelli
- Gothenburg Global Biodiversity Centre, Box 461, 405 30, Gothenburg, Sweden
- Department of Biological and Environmental Sciences, University of Gothenburg, Box 461, 405 30, Gothenburg, Sweden
- Gothenburg Botanical Garden, Carl Skottsbergs Gata 22B, SE-413 19, Gothenburg, Sweden
| | - Dominic J Bennett
- Gothenburg Global Biodiversity Centre, Box 461, 405 30, Gothenburg, Sweden
- Department of Biological and Environmental Sciences, University of Gothenburg, Box 461, 405 30, Gothenburg, Sweden
- Gothenburg Botanical Garden, Carl Skottsbergs Gata 22B, SE-413 19, Gothenburg, Sweden
| | | | | | | | - Brian J Enquist
- Department of Ecology and Evolutionary Biology, University of Arizona, Tucson, AZ, 85721, USA
- The Santa Fe Institute, Santa Fe, NM, 87501, USA
| | - Félix Forest
- Royal Botanic Gardens, Kew, TW9 3AE, Richmond, Surrey, UK
| | - Jan T Kim
- Royal Botanic Gardens, Kew, TW9 3AE, Richmond, Surrey, UK
| | - Alexey M Kozlov
- Scientific Computing Group, Heidelberg Institute for Theoretical Studies, 69118, Heidelberg, Germany
| | - Ilia J Leitch
- Royal Botanic Gardens, Kew, TW9 3AE, Richmond, Surrey, UK
| | - Brian S Maitner
- Department of Ecology and Evolutionary Biology, University of Arizona, Tucson, AZ, 85721, USA
| | - Siavash Mirarab
- Department of Electrical and Computer Engineering, University of California, San Diego, San Diego, CA, 92093, USA
| | - William H Piel
- Yale-NUS College, 16 College Avenue West, Singapore, 138527, Republic of Singapore
| | | | - Lisa Pokorny
- Royal Botanic Gardens, Kew, TW9 3AE, Richmond, Surrey, UK
| | - Carsten Rahbek
- Center for Macroecology, Evolution and Climate, University of Copenhagen, Universitetsparken 15, DK-2100, Copenhagen O, Denmark
- Imperial College London, Silwood Park, Buckhurst Road, Ascot, Berkshire, SL5 7PY, UK
| | - Brody Sandel
- Department of Biology, Santa Clara University, Santa Clara, CA, 95053, USA
| | - Stephen A Smith
- Department of Ecology and Evolutionary Biology, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Alexandros Stamatakis
- Scientific Computing Group, Heidelberg Institute for Theoretical Studies, 69118, Heidelberg, Germany
- Institute for Theoretical Informatics, Karlsruhe Institute of Technology, 76128, Karlsruhe, Germany
| | - Rutger A Vos
- Naturalis Biodiversity Center, P.O. Box 9517, 2300RA, Leiden, The Netherlands
- Institute of Biology Leiden, P.O. Box 9505, 2300RA, Leiden, The Netherlands
| | - Tandy Warnow
- Department of Computer Science, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
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28
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Zhou Z, Liu Y, Li M, Gu JD. Two or three domains: a new view of tree of life in the genomics era. Appl Microbiol Biotechnol 2018; 102:3049-3058. [PMID: 29484479 DOI: 10.1007/s00253-018-8831-x] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2017] [Revised: 01/30/2018] [Accepted: 02/01/2018] [Indexed: 12/26/2022]
Abstract
The deep phylogenetic topology of tree of life is in the center of a long-time dispute. The Woeseian three-domain tree theory, with the Eukarya evolving as a sister clade to Archaea, competes with the two-domain tree theory (the eocyte tree), with the Eukarya branched within Archaea. Revealed by the ongoing debate over the last three decades, sophisticated and proper phylogenetic methods should necessarily be paid with more emphasis, especially these are focusing on the compositional heterogeneity of sites and lineages, and the heterotachy issue. The newly emerging archaeal lineages with numerous eukaryotic-like features, such as membrane trafficking and cellular compartmentalization, are phylogenetically the closest to eukaryotes currently. These findings highlight the evolutionary history from an ancient archaeon to a more complex archaeon with protoeukaryotic-like features and complex cellular structures, thus providing clues to understand eukaryogenesis process. The increasing repertoire of precise genomic contents provides great advantages on understanding the deep phylogeny of tree of life and ancient evolutionary events on Eukarya branching process.
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Affiliation(s)
- Zhichao Zhou
- Institute for Advanced Study, Shenzhen University, Shenzhen, 518060, People's Republic of China.,Laboratory of Environmental Microbiology and Toxicology, School of Biological Sciences, The University of Hong Kong, Pokfulam Road, Hong Kong SAR, Hong Kong, People's Republic of China
| | - Yang Liu
- Institute for Advanced Study, Shenzhen University, Shenzhen, 518060, People's Republic of China.,Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, College of Optoelectronic Engineering, Shenzhen University, Shenzhen, 518060, People's Republic of China
| | - Meng Li
- Institute for Advanced Study, Shenzhen University, Shenzhen, 518060, People's Republic of China.
| | - Ji-Dong Gu
- Laboratory of Environmental Microbiology and Toxicology, School of Biological Sciences, The University of Hong Kong, Pokfulam Road, Hong Kong SAR, Hong Kong, People's Republic of China
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Eme L, Spang A, Lombard J, Stairs CW, Ettema TJG. Archaea and the origin of eukaryotes. Nat Rev Microbiol 2017; 15:711-723. [DOI: 10.1038/nrmicro.2017.133] [Citation(s) in RCA: 279] [Impact Index Per Article: 39.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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31
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Duchêne DA, Duchêne S, Ho SYW. New Statistical Criteria Detect Phylogenetic Bias Caused by Compositional Heterogeneity. Mol Biol Evol 2017; 34:1529-1534. [PMID: 28333201 DOI: 10.1093/molbev/msx092] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
In statistical phylogenetic analyses of DNA sequences, models of evolutionary change commonly assume that base composition is stationary through time and across lineages. This assumption is violated by many data sets, but it is unclear whether the magnitude of these violations is sufficient to mislead phylogenetic inference. We investigated the impacts of compositional heterogeneity on phylogenetic estimates using a method for assessing model adequacy. Based on a detailed simulation study, we found that common frequentist criteria are highly conservative, such that the model is often rejected when the phylogenetic estimates do not show clear signs of bias. We propose new criteria and provide guidelines for their usage. We apply these criteria to genome-scale data from 40 birds and find that loci with severely non-homogeneous base composition are uncommon. Our results show the importance of using well-informed diagnostic statistics when testing model adequacy for phylogenomic analyses.
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Affiliation(s)
- David A Duchêne
- School of Life and Environmental Sciences, University of Sydney, Sydney, NSW, Australia
| | - Sebastian Duchêne
- Centre for Systems Genomics, University of Melbourne, Melbourne, VIC, Australia
| | - Simon Y W Ho
- School of Life and Environmental Sciences, University of Sydney, Sydney, NSW, Australia
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32
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Kück P, Wilkinson M, Groß C, Foster PG, Wägele JW. Can quartet analyses combining maximum likelihood estimation and Hennigian logic overcome long branch attraction in phylogenomic sequence data? PLoS One 2017; 12:e0183393. [PMID: 28841676 PMCID: PMC5571918 DOI: 10.1371/journal.pone.0183393] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2017] [Accepted: 08/03/2017] [Indexed: 12/28/2022] Open
Abstract
Systematic biases such as long branch attraction can mislead commonly relied upon model-based (i.e. maximum likelihood and Bayesian) phylogenetic methods when, as is usually the case with empirical data, there is model misspecification. We present PhyQuart, a new method for evaluating the three possible binary trees for any quartet of taxa. PhyQuart was developed through a process of reciprocal illumination between a priori considerations and the results of extensive simulations. It is based on identification of site-patterns that can be considered to support a particular quartet tree taking into account the Hennigian distinction between apomorphic and plesiomorphic similarity, and employing corrections to the raw observed frequencies of site-patterns that exploit expectations from maximum likelihood estimation. We demonstrate through extensive simulation experiments that, whereas maximum likeilihood estimation performs well in many cases, it can be outperformed by PhyQuart in cases where it fails due to extreme branch length asymmetries producing long-branch attraction artefacts where there is only very minor model misspecification.
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Affiliation(s)
- Patrick Kück
- Zoologisches Forschungsmuseum Alexander Koenig, Bonn, 53113, Germany
- The Natural History Museum, London, SW7 5BD, United Kingdom
| | - Mark Wilkinson
- The Natural History Museum, London, SW7 5BD, United Kingdom
| | - Christian Groß
- The Natural History Museum, London, SW7 5BD, United Kingdom
- Delft University of Technology, Delft, 2628 CD, The Netherlands
| | | | - Johann W. Wägele
- Zoologisches Forschungsmuseum Alexander Koenig, Bonn, 53113, Germany
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Heimerl T, Flechsler J, Pickl C, Heinz V, Salecker B, Zweck J, Wanner G, Geimer S, Samson RY, Bell SD, Huber H, Wirth R, Wurch L, Podar M, Rachel R. A Complex Endomembrane System in the Archaeon Ignicoccus hospitalis Tapped by Nanoarchaeum equitans. Front Microbiol 2017; 8:1072. [PMID: 28659892 PMCID: PMC5468417 DOI: 10.3389/fmicb.2017.01072] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2017] [Accepted: 05/29/2017] [Indexed: 11/25/2022] Open
Abstract
Based on serial sectioning, focused ion beam scanning electron microscopy (FIB/SEM), and electron tomography, we depict in detail the highly unusual anatomy of the marine hyperthermophilic crenarchaeon, Ignicoccus hospitalis. Our data support a complex and dynamic endomembrane system consisting of cytoplasmic protrusions, and with secretory function. Moreover, we reveal that the cytoplasm of the putative archaeal ectoparasite Nanoarchaeum equitans can get in direct contact with this endomembrane system, complementing and explaining recent proteomic, transcriptomic and metabolomic data on this inter-archaeal relationship. In addition, we identified a matrix of filamentous structures and/or tethers in the voluminous inter-membrane compartment (IMC) of I. hospitalis, which might be responsible for membrane dynamics. Overall, this unusual cellular compartmentalization, ultrastructure and dynamics in an archaeon that belongs to the recently proposed TACK superphylum prompts speculation that the eukaryotic endomembrane system might originate from Archaea.
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Affiliation(s)
- Thomas Heimerl
- LOEWE Research Center for Synthetic Microbiology (SYNMIKRO), Philipps University of MarburgMarburg, Germany
| | | | - Carolin Pickl
- Plant Development and Electron Microscopy, Biocenter LMUMunich, Germany
| | - Veronika Heinz
- Center for Electron Microscopy, University of RegensburgRegensburg, Germany
| | - Benjamin Salecker
- Center for Electron Microscopy, University of RegensburgRegensburg, Germany
| | - Josef Zweck
- Institute of Experimental and Applied Physics, University of RegensburgRegensburg, Germany
| | - Gerhard Wanner
- Plant Development and Electron Microscopy, Biocenter LMUMunich, Germany
| | - Stefan Geimer
- Cell Biology and Electron Microscopy, University of BayreuthBayreuth, Germany
| | - Rachel Y. Samson
- Molecular and Cellular Biochemistry Department, Indiana UniversityBloomington, IN, United States
| | - Stephen D. Bell
- Molecular and Cellular Biochemistry Department, Indiana UniversityBloomington, IN, United States
| | - Harald Huber
- Microbiology Department, University of RegensburgRegensburg, Germany
| | - Reinhard Wirth
- Microbiology Department, University of RegensburgRegensburg, Germany
| | - Louie Wurch
- Biosciences Division, Oak Ridge National LaboratoryOak Ridge, TN, United States
- Microbiology Department, University of TennesseeKnoxville, TN, United States
| | - Mircea Podar
- Biosciences Division, Oak Ridge National LaboratoryOak Ridge, TN, United States
- Microbiology Department, University of TennesseeKnoxville, TN, United States
| | - Reinhard Rachel
- Center for Electron Microscopy, University of RegensburgRegensburg, Germany
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Williams TA, Szöllősi GJ, Spang A, Foster PG, Heaps SE, Boussau B, Ettema TJG, Embley TM. Integrative modeling of gene and genome evolution roots the archaeal tree of life. Proc Natl Acad Sci U S A 2017; 114:E4602-E4611. [PMID: 28533395 PMCID: PMC5468678 DOI: 10.1073/pnas.1618463114] [Citation(s) in RCA: 146] [Impact Index Per Article: 20.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
A root for the archaeal tree is essential for reconstructing the metabolism and ecology of early cells and for testing hypotheses that propose that the eukaryotic nuclear lineage originated from within the Archaea; however, published studies based on outgroup rooting disagree regarding the position of the archaeal root. Here we constructed a consensus unrooted archaeal topology using protein concatenation and a multigene supertree method based on 3,242 single gene trees, and then rooted this tree using a recently developed model of genome evolution. This model uses evidence from gene duplications, horizontal transfers, and gene losses contained in 31,236 archaeal gene families to identify the most likely root for the tree. Our analyses support the monophyly of DPANN (Diapherotrites, Parvarchaeota, Aenigmarchaeota, Nanoarchaeota, Nanohaloarchaea), a recently discovered cosmopolitan and genetically diverse lineage, and, in contrast to previous work, place the tree root between DPANN and all other Archaea. The sister group to DPANN comprises the Euryarchaeota and the TACK Archaea, including Lokiarchaeum, which our analyses suggest are monophyletic sister lineages. Metabolic reconstructions on the rooted tree suggest that early Archaea were anaerobes that may have had the ability to reduce CO2 to acetate via the Wood-Ljungdahl pathway. In contrast to proposals suggesting that genome reduction has been the predominant mode of archaeal evolution, our analyses infer a relatively small-genomed archaeal ancestor that subsequently increased in complexity via gene duplication and horizontal gene transfer.
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Affiliation(s)
- Tom A Williams
- School of Earth Sciences, University of Bristol, Bristol BS8 1TQ, United Kingdom;
- Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle upon Tyne NE2 4HH, United Kingdom
| | - Gergely J Szöllősi
- MTA-ELTE Lendület Evolutionary Genomics Research Group, 1117 Budapest, Hungary
| | - Anja Spang
- Department of Cell and Molecular Biology, Science for Life Laboratory, Uppsala University, SE-75123 Uppsala, Sweden
| | - Peter G Foster
- Department of Life Sciences, Natural History Museum, London SW7 5BD, United Kingdom
| | - Sarah E Heaps
- Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle upon Tyne NE2 4HH, United Kingdom
- School of Mathematics & Statistics, Newcastle University, Newcastle upon Tyne NE1 7RU, United Kingdom
| | - Bastien Boussau
- Univ Lyon, Université Lyon 1, CNRS, Laboratoire de Biométrie et Biologie Evolutive UMR5558, F-69622 Villeurbanne, France
| | - Thijs J G Ettema
- Department of Cell and Molecular Biology, Science for Life Laboratory, Uppsala University, SE-75123 Uppsala, Sweden
| | - T Martin Embley
- Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle upon Tyne NE2 4HH, United Kingdom
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35
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Shapiro JA. Nothing in Evolution Makes Sense Except in the Light of Genomics: Read-Write Genome Evolution as an Active Biological Process. BIOLOGY 2016; 5:E27. [PMID: 27338490 PMCID: PMC4929541 DOI: 10.3390/biology5020027] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 02/12/2016] [Revised: 05/20/2016] [Accepted: 06/02/2016] [Indexed: 01/15/2023]
Abstract
The 21st century genomics-based analysis of evolutionary variation reveals a number of novel features impossible to predict when Dobzhansky and other evolutionary biologists formulated the neo-Darwinian Modern Synthesis in the middle of the last century. These include three distinct realms of cell evolution; symbiogenetic fusions forming eukaryotic cells with multiple genome compartments; horizontal organelle, virus and DNA transfers; functional organization of proteins as systems of interacting domains subject to rapid evolution by exon shuffling and exonization; distributed genome networks integrated by mobile repetitive regulatory signals; and regulation of multicellular development by non-coding lncRNAs containing repetitive sequence components. Rather than single gene traits, all phenotypes involve coordinated activity by multiple interacting cell molecules. Genomes contain abundant and functional repetitive components in addition to the unique coding sequences envisaged in the early days of molecular biology. Combinatorial coding, plus the biochemical abilities cells possess to rearrange DNA molecules, constitute a powerful toolbox for adaptive genome rewriting. That is, cells possess "Read-Write Genomes" they alter by numerous biochemical processes capable of rapidly restructuring cellular DNA molecules. Rather than viewing genome evolution as a series of accidental modifications, we can now study it as a complex biological process of active self-modification.
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Affiliation(s)
- James A Shapiro
- Department of Biochemistry and Molecular Biology, University of Chicago, GCIS W123B, 979 E. 57th Street, Chicago, IL 60637, USA.
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36
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Abstract
The origin of the eukaryotes is a fundamental scientific question that for over 30 years has generated a spirited debate between the competing Archaea (or three domains) tree and the eocyte tree. As eukaryotes ourselves, humans have a personal interest in our origins. Eukaryotes contain their defining organelle, the nucleus, after which they are named. They have a complex evolutionary history, over time acquiring multiple organelles, including mitochondria, chloroplasts, smooth and rough endoplasmic reticula, and other organelles all of which may hint at their origins. It is the evolutionary history of the nucleus and their other organelles that have intrigued molecular evolutionists, myself included, for the past 30 years and which continues to hold our interest as increasingly compelling evidence favours the eocyte tree. As with any orthodoxy, it takes time to embrace new concepts and techniques.
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Affiliation(s)
- James A Lake
- MCDB Biology and Human Genetics, University of California, 232 Boyer Hall, Los Angeles, CA 90095, USA
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37
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Klinger CM, Spang A, Dacks JB, Ettema TJG. Tracing the Archaeal Origins of Eukaryotic Membrane-Trafficking System Building Blocks. Mol Biol Evol 2016; 33:1528-41. [PMID: 26893300 DOI: 10.1093/molbev/msw034] [Citation(s) in RCA: 60] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
In contrast to prokaryotes, eukaryotic cells are characterized by a complex set of internal membrane-bound compartments. A subset of these, and the protein machineries that move material between them, define the membrane-trafficking system (MTS), the emergence of which represents a landmark in eukaryotic evolution. Unlike mitochondria and plastids, MTS organelles have autogenous origins. Much of the MTS machinery is composed of building blocks, including small GTPase, coiled-coil, beta-propeller + alpha-solenoid, and longin domains. Despite the identification of prokaryotic proteins containing these domains, only few represent direct orthologues, leaving the origins and early evolution of the MTS poorly understood. Here, we present an in-depth analysis of MTS building block homologues in the composite genome of Lokiarchaeum, the recently discovered archaeal sister clade of eukaryotes, yielding several key insights. We identify two previously unreported Eukaryotic Signature Proteins; orthologues of the Gtr/Rag family GTPases, involved in target of rapamycin complex signaling, and of the RLC7 dynein component. We could not identify golgin or SNARE (coiled-coil) or beta-propeller + alpha-solenoid orthologues, nor typical MTS domain fusions, suggesting that these either were lost from Lokiarchaeum or emerged later in eukaryotic evolution. Furthermore, our phylogenetic analyses of lokiarchaeal GTPases support a split into Ras-like and Arf-like superfamilies, with different prokaryotic antecedents, before the advent of eukaryotes. While no GTPase activating proteins or exchange factors were identified, we show that Lokiarchaeum encodes numerous roadblock domain proteins and putative longin domain proteins, confirming the latter's origin from Archaea. Altogether, our study provides new insights into the emergence and early evolution of the eukaryotic membrane-trafficking system.
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Affiliation(s)
| | - Anja Spang
- Department of Cell and Molecular Biology, Science for Life Laboratory, Uppsala University, Uppsala, Sweden
| | - Joel B Dacks
- Department of Cell Biology, University of Alberta, Edmonton, AB, Canada
| | - Thijs J G Ettema
- Department of Cell and Molecular Biology, Science for Life Laboratory, Uppsala University, Uppsala, Sweden
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38
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Timmermans MJTN, Barton C, Haran J, Ahrens D, Culverwell CL, Ollikainen A, Dodsworth S, Foster PG, Bocak L, Vogler AP. Family-Level Sampling of Mitochondrial Genomes in Coleoptera: Compositional Heterogeneity and Phylogenetics. Genome Biol Evol 2015; 8:161-75. [PMID: 26645679 PMCID: PMC4758238 DOI: 10.1093/gbe/evv241] [Citation(s) in RCA: 123] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/28/2015] [Indexed: 12/29/2022] Open
Abstract
Mitochondrial genomes are readily sequenced with recent technology and thus evolutionary lineages can be densely sampled. This permits better phylogenetic estimates and assessment of potential biases resulting from heterogeneity in nucleotide composition and rate of change. We gathered 245 mitochondrial sequences for the Coleoptera representing all 4 suborders, 15 superfamilies of Polyphaga, and altogether 97 families, including 159 newly sequenced full or partial mitogenomes. Compositional heterogeneity greatly affected 3rd codon positions, and to a lesser extent the 1st and 2nd positions, even after RY coding. Heterogeneity also affected the encoded protein sequence, in particular in the nad2, nad4, nad5, and nad6 genes. Credible tree topologies were obtained with the nhPhyML ("nonhomogeneous") algorithm implementing a model for branch-specific equilibrium frequencies. Likelihood searches using RAxML were improved by data partitioning by gene and codon position. Finally, the PhyloBayes software, which allows different substitution processes for amino acid replacement at various sites, produced a tree that best matched known higher level taxa and defined basal relationships in Coleoptera. After rooting with Neuropterida outgroups, suborder relationships were resolved as (Polyphaga (Myxophaga (Archostemata + Adephaga))). The infraorder relationships in Polyphaga were (Scirtiformia (Elateriformia ((Staphyliniformia + Scarabaeiformia) (Bostrichiformia (Cucujiformia))))). Polyphagan superfamilies were recovered as monophyla except Staphylinoidea (paraphyletic for Scarabaeiformia) and Cucujoidea, which can no longer be considered a valid taxon. The study shows that, although compositional heterogeneity is not universal, it cannot be eliminated for some mitochondrial genes, but dense taxon sampling and the use of appropriate Bayesian analyses can still produce robust phylogenetic trees.
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Affiliation(s)
- Martijn J T N Timmermans
- Department of Life Sciences, Natural History Museum, London, United Kingdom Department of Life Sciences, Imperial College London - Silwood Park Campus, Ascot, United Kingdom Department of Natural Sciences, Middlesex University, Hendon Campus, London, United Kingdom
| | - Christopher Barton
- Department of Life Sciences, Natural History Museum, London, United Kingdom
| | - Julien Haran
- Department of Life Sciences, Natural History Museum, London, United Kingdom Present address: INRA, UR633 Zoologie Forestière, Orléans, France
| | - Dirk Ahrens
- Department of Life Sciences, Natural History Museum, London, United Kingdom Zoologisches Forschungsmuseum Alexander Koenig Bonn, Bonn, Germany
| | - C Lorna Culverwell
- Department of Life Sciences, Natural History Museum, London, United Kingdom Present address: Haartman Institute, Haartmaninkatu 3, University of Helsinki, Helsinki, Finland
| | - Alison Ollikainen
- Department of Life Sciences, Natural History Museum, London, United Kingdom Present address: Department of Medical Genetics, Genome-Scale Biology Research Program, University of Helsinki, Helsinki, Finland
| | - Steven Dodsworth
- Department of Life Sciences, Natural History Museum, London, United Kingdom Present address: Department of Comparative Plant and Fungal Biology, Royal Botanic Gardens, Kew, Richmond, Surrey, United Kingdom
| | - Peter G Foster
- Department of Life Sciences, Natural History Museum, London, United Kingdom
| | - Ladislav Bocak
- Department of Life Sciences, Natural History Museum, London, United Kingdom Department of Zoology, Faculty of Science UP, Olomouc, Czech Republic
| | - Alfried P Vogler
- Department of Life Sciences, Natural History Museum, London, United Kingdom Department of Life Sciences, Imperial College London - Silwood Park Campus, Ascot, United Kingdom
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39
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Williams TA, Heaps SE, Cherlin S, Nye TMW, Boys RJ, Embley TM. New substitution models for rooting phylogenetic trees. Philos Trans R Soc Lond B Biol Sci 2015; 370:20140336. [PMID: 26323766 PMCID: PMC4571574 DOI: 10.1098/rstb.2014.0336] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/04/2015] [Indexed: 12/23/2022] Open
Abstract
The root of a phylogenetic tree is fundamental to its biological interpretation, but standard substitution models do not provide any information on its position. Here, we describe two recently developed models that relax the usual assumptions of stationarity and reversibility, thereby facilitating root inference without the need for an outgroup. We compare the performance of these models on a classic test case for phylogenetic methods, before considering two highly topical questions in evolutionary biology: the deep structure of the tree of life and the root of the archaeal radiation. We show that all three alignments contain meaningful rooting information that can be harnessed by these new models, thus complementing and extending previous work based on outgroup rooting. In particular, our analyses exclude the root of the tree of life from the eukaryotes or Archaea, placing it on the bacterial stem or within the Bacteria. They also exclude the root of the archaeal radiation from several major clades, consistent with analyses using other rooting methods. Overall, our results demonstrate the utility of non-reversible and non-stationary models for rooting phylogenetic trees, and identify areas where further progress can be made.
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Affiliation(s)
- Tom A Williams
- Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle upon Tyne NE2 4HH, UK
| | - Sarah E Heaps
- Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle upon Tyne NE2 4HH, UK School of Mathematics and Statistics, Newcastle University, Newcastle upon Tyne NE1 7RU, UK
| | - Svetlana Cherlin
- Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle upon Tyne NE2 4HH, UK School of Mathematics and Statistics, Newcastle University, Newcastle upon Tyne NE1 7RU, UK
| | - Tom M W Nye
- School of Mathematics and Statistics, Newcastle University, Newcastle upon Tyne NE1 7RU, UK
| | - Richard J Boys
- School of Mathematics and Statistics, Newcastle University, Newcastle upon Tyne NE1 7RU, UK
| | - T Martin Embley
- Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle upon Tyne NE2 4HH, UK
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40
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Abstract
SUMMARY Members of the Roseobacter clade are equipped with a tremendous diversity of metabolic capabilities, which in part explains their success in so many different marine habitats. Ideas on how this diversity evolved and is maintained are reviewed, focusing on recent evolutionary studies exploring the timing and mechanisms of Roseobacter ecological diversification.
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41
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Abstract
One of the most fundamental questions in evolutionary biology is the origin of the lineage leading to eukaryotes. Recent phylogenomic analyses have indicated an emergence of eukaryotes from within the radiation of modern Archaea and specifically from a group comprising Thaumarchaeota/"Aigarchaeota" (candidate phylum)/Crenarchaeota/Korarchaeota (TACK). Despite their major implications, these studies were all based on the reconstruction of universal trees and left the exact placement of eukaryotes with respect to the TACK lineage unclear. Here we have applied an original two-step approach that involves the separate analysis of markers shared between Archaea and eukaryotes and between Archaea and Bacteria. This strategy allowed us to use a larger number of markers and greater taxonomic coverage, obtain high-quality alignments, and alleviate tree reconstruction artifacts potentially introduced when analyzing the three domains simultaneously. Our results robustly indicate a sister relationship of eukaryotes with the TACK superphylum that is strongly associated with a distinct root of the Archaea that lies within the Euryarchaeota, challenging the traditional topology of the archaeal tree. Therefore, if we are to embrace an archaeal origin for eukaryotes, our view of the evolution of the third domain of life will have to be profoundly reconsidered, as will many areas of investigation aimed at inferring ancestral characteristics of early life and Earth.
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42
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Spang A, Saw JH, Jørgensen SL, Zaremba-Niedzwiedzka K, Martijn J, Lind AE, van Eijk R, Schleper C, Guy L, Ettema TJG. Complex archaea that bridge the gap between prokaryotes and eukaryotes. Nature 2015; 521:173-179. [PMID: 25945739 PMCID: PMC4444528 DOI: 10.1038/nature14447] [Citation(s) in RCA: 694] [Impact Index Per Article: 77.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2014] [Accepted: 04/01/2015] [Indexed: 12/22/2022]
Abstract
The origin of the eukaryotic cell remains one of the most contentious puzzles in modern biology. Recent studies have provided support for the emergence of the eukaryotic host cell from within the archaeal domain of life, but the identity and nature of the putative archaeal ancestor remain a subject of debate. Here we describe the discovery of 'Lokiarchaeota', a novel candidate archaeal phylum, which forms a monophyletic group with eukaryotes in phylogenomic analyses, and whose genomes encode an expanded repertoire of eukaryotic signature proteins that are suggestive of sophisticated membrane remodelling capabilities. Our results provide strong support for hypotheses in which the eukaryotic host evolved from a bona fide archaeon, and demonstrate that many components that underpin eukaryote-specific features were already present in that ancestor. This provided the host with a rich genomic 'starter-kit' to support the increase in the cellular and genomic complexity that is characteristic of eukaryotes.
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Affiliation(s)
- Anja Spang
- Department of Cell and Molecular Biology, Science for Life Laboratory, Uppsala University, SE-75123 Uppsala, Sweden
| | - Jimmy H Saw
- Department of Cell and Molecular Biology, Science for Life Laboratory, Uppsala University, SE-75123 Uppsala, Sweden
| | - Steffen L Jørgensen
- Department of Biology, Centre for Geobiology, University of Bergen, N-5020 Bergen, Norway
| | | | - Joran Martijn
- Department of Cell and Molecular Biology, Science for Life Laboratory, Uppsala University, SE-75123 Uppsala, Sweden
| | - Anders E Lind
- Department of Cell and Molecular Biology, Science for Life Laboratory, Uppsala University, SE-75123 Uppsala, Sweden
| | - Roel van Eijk
- Department of Cell and Molecular Biology, Science for Life Laboratory, Uppsala University, SE-75123 Uppsala, Sweden
| | - Christa Schleper
- Department of Biology, Centre for Geobiology, University of Bergen, N-5020 Bergen, Norway.,Division of Archaea Biology and Ecogenomics, Department of Ecogenomics and Systems Biology, University of Vienna, A-1090 Vienna, Austria
| | - Lionel Guy
- Department of Cell and Molecular Biology, Science for Life Laboratory, Uppsala University, SE-75123 Uppsala, Sweden.,Department of Medical Biochemistry and Microbiology, Uppsala University, SE-75123 Uppsala, Sweden
| | - Thijs J G Ettema
- Department of Cell and Molecular Biology, Science for Life Laboratory, Uppsala University, SE-75123 Uppsala, Sweden
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43
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Mosaic nature of the mitochondrial proteome: Implications for the origin and evolution of mitochondria. Proc Natl Acad Sci U S A 2015; 112:10133-8. [PMID: 25848019 DOI: 10.1073/pnas.1421379112] [Citation(s) in RCA: 112] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Comparative studies of the mitochondrial proteome have identified a conserved core of proteins descended from the α-proteobacterial endosymbiont that gave rise to the mitochondrion and was the source of the mitochondrial genome in contemporary eukaryotes. A surprising result of phylogenetic analyses is the relatively small proportion (10-20%) of the mitochondrial proteome displaying a clear α-proteobacterial ancestry. A large fraction of mitochondrial proteins typically has detectable homologs only in other eukaryotes and is presumed to represent proteins that emerged specifically within eukaryotes. A further significant fraction of the mitochondrial proteome consists of proteins with homologs in prokaryotes, but without a robust phylogenetic signal affiliating them with specific prokaryotic lineages. The presumptive evolutionary source of these proteins is quite different in contending models of mitochondrial origin.
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44
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Domman D, Horn M, Embley TM, Williams TA. Plastid establishment did not require a chlamydial partner. Nat Commun 2015; 6:6421. [PMID: 25758953 PMCID: PMC4374161 DOI: 10.1038/ncomms7421] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2014] [Accepted: 01/27/2015] [Indexed: 12/28/2022] Open
Abstract
Primary plastids descend from the cyanobacterial endosymbiont of an ancient eukaryotic host, but the initial selective drivers that stabilized the association between these two cells are still unclear. One hypothesis that has achieved recent prominence suggests that the first role of the cyanobiont was in energy provision for a host cell whose reserves were being depleted by an intracellular chlamydial pathogen. A pivotal claim is that it was chlamydial proteins themselves that converted otherwise unusable cyanobacterial metabolites into host energy stores. We test this hypothesis by investigating the origins of the key enzymes using sophisticated phylogenetics. Here we show a mosaic origin for the relevant pathway combining genes with host, cyanobacterial or bacterial ancestry, but we detect no strong case for Chlamydiae to host transfer under the best-fitting models. Our conclusion is that there is no compelling evidence from gene trees that Chlamydiae played any role in establishing the primary plastid endosymbiosis. Primary plastids descend from an endosymbiosis involving cyanobacteria, an ancient eukaryotic host and, possibly, a chlamydial pathogen. Here, Domman and colleagues use sophisticated phylogenetic methods to show that Chlamydiae did not play a role in establishing the primary plastid endosymbiosis.
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Affiliation(s)
- Daryl Domman
- Department of Microbiology and Ecosystem Science, University of Vienna, A-1090 Vienna, Austria
| | - Matthias Horn
- Department of Microbiology and Ecosystem Science, University of Vienna, A-1090 Vienna, Austria
| | - T Martin Embley
- Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle upon Tyne NE2 4HH, UK
| | - Tom A Williams
- Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle upon Tyne NE2 4HH, UK
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45
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Luo H. The use of evolutionary approaches to understand single cell genomes. Front Microbiol 2015; 6:174. [PMID: 25806025 PMCID: PMC4354383 DOI: 10.3389/fmicb.2015.00191] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2014] [Accepted: 02/20/2015] [Indexed: 11/13/2022] Open
Abstract
The vast majority of environmental bacteria and archaea remain uncultivated, yet their genome sequences are rapidly becoming available through single cell sequencing technologies. Reconstructing metabolism is one common way to make use of genome sequences of ecologically important bacteria, but molecular evolutionary analysis is another approach that, while currently underused, can reveal important insights into the function of these uncultivated microbes in nature. Because genome sequences from single cells are often incomplete, metabolic reconstruction based on genome content can be compromised. However, this problem does not necessarily impede the use of phylogenomic and population genomic approaches that are based on patterns of polymorphisms and substitutions at nucleotide and amino acid sites. These approaches explore how various evolutionary forces act to assemble genetic diversity within and between lineages. In this mini-review, I present examples illustrating the benefits of analyzing single cell genomes using evolutionary approaches.
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Affiliation(s)
- Haiwei Luo
- Simon F. S. Li Marine Science Laboratory, School of Life Sciences, The Chinese University of Hong Kong Hong Kong, China
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46
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Abstract
The large phylogenetic distance separating eukaryotic genes and their archaeal orthologs has prevented identification of the position of the eukaryotic root in phylogenomic studies. Recently, an innovative approach has been proposed to circumvent this issue: the use as phylogenetic markers of proteins that have been transferred from bacterial donor sources to eukaryotes, after their emergence from Archaea. Using this approach, two recent independent studies have built phylogenomic datasets based on bacterial sequences, leading to different predictions of the eukaryotic root. Taking advantage of additional genome sequences from the jakobid Andalucia godoyi and the two known malawimonad species (Malawimonas jakobiformis and Malawimonas californiana), we reanalyzed these two phylogenomic datasets. We show that both datasets pinpoint the same phylogenetic position of the eukaryotic root that is between "Unikonta" and "Bikonta," with malawimonad and collodictyonid lineages on the Unikonta side of the root. Our results firmly indicate that (i) the supergroup Excavata is not monophyletic and (ii) the last common ancestor of eukaryotes was a biflagellate organism. Based on our results, we propose to rename the two major eukaryotic groups Unikonta and Bikonta as Opimoda and Diphoda, respectively.
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47
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Luo H. Evolutionary origin of a streamlined marine bacterioplankton lineage. ISME JOURNAL 2014; 9:1423-33. [PMID: 25431989 DOI: 10.1038/ismej.2014.227] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/11/2014] [Revised: 10/23/2014] [Accepted: 10/30/2014] [Indexed: 12/31/2022]
Abstract
Planktonic bacterial lineages with streamlined genomes are prevalent in the ocean. The base composition of their DNA is often highly biased towards low G+C content, a possible source of systematic error in phylogenetic reconstruction. A total of 228 orthologous protein families were sampled that are shared among major lineages of Alphaproteobacteria, including the marine free-living SAR11 clade and the obligate endosymbiotic Rickettsiales. These two ecologically distinct lineages share genome sizes of <1.5 Mbp and genomic G+C content of <30%. Statistical analyses showed that only 28 protein families are composition-homogeneous, whereas the other 200 families significantly violate the composition-homogeneous assumption included in most phylogenetic methods. RAxML analysis based on the concatenation of 24 ribosomal proteins that fall into the heterogeneous protein category clustered the SAR11 and Rickettsiales lineages at the base of the Alphaproteobacteria tree, whereas that based on the concatenation of 28 homogeneous proteins (including 19 ribosomal proteins) disassociated the lineages and placed SAR11 at the base of the non-endosymbiotic lineages. When the two data sets were concatenated, only a model that accounted for compositional bias yielded a tree identical to the tree built with composition-homogeneous proteins. Ancestral genome analysis suggests that the first evolved SAR11 cell had a small genome streamlined from its ancestor by a factor of two and coinciding with an ecological transition, followed by further gradual streamlining towards the extant SAR11 populations.
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Affiliation(s)
- Haiwei Luo
- Simon F. S. Li Marine Science Laboratory, School of Life Sciences, The Chinese University of Hong Kong, Shatin, Hong Kong, China
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48
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Abstract
Current hypotheses about the history of cellular life are mainly based on analyses of cultivated organisms, but these represent only a small fraction of extant biodiversity. The sequencing of new environmental lineages therefore provides an opportunity to test, revise, or reject existing ideas about the tree of life and the origin of eukaryotes. According to the textbook three domains hypothesis, the eukaryotes emerge as the sister group to a monophyletic Archaea. However, recent analyses incorporating better phylogenetic models and an improved sampling of the archaeal domain have generally supported the competing eocyte hypothesis, in which core genes of eukaryotic cells originated from within the Archaea, with important implications for eukaryogenesis. Given this trend, it was surprising that a recent analysis incorporating new genomes from uncultivated Archaea recovered a strongly supported three domains tree. Here, we show that this result was due in part to the use of a poorly fitting phylogenetic model and also to the inclusion by an automated pipeline of genes of putative bacterial origin rather than nucleocytosolic versions for some of the eukaryotes analyzed. When these issues were resolved, analyses including the new archaeal lineages placed core eukaryotic genes within the Archaea. These results are consistent with a number of recent studies in which improved archaeal sampling and better phylogenetic models agree in supporting the eocyte tree over the three domains hypothesis.
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Affiliation(s)
- Tom A Williams
- Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle upon Tyne, United Kingdom
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49
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Raymann K, Forterre P, Brochier-Armanet C, Gribaldo S. Global phylogenomic analysis disentangles the complex evolutionary history of DNA replication in archaea. Genome Biol Evol 2014; 6:192-212. [PMID: 24398374 PMCID: PMC3914693 DOI: 10.1093/gbe/evu004] [Citation(s) in RCA: 65] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
The archaeal machinery responsible for DNA replication is largely homologous to that of eukaryotes and is clearly distinct from its bacterial counterpart. Moreover, it shows high diversity in the various archaeal lineages, including different sets of components, heterogeneous taxonomic distribution, and a large number of additional copies that are sometimes highly divergent. This has made the evolutionary history of this cellular system particularly challenging to dissect. Here, we have carried out an exhaustive identification of homologs of all major replication components in over 140 complete archaeal genomes. Phylogenomic analysis allowed assigning them to either a conserved and probably essential core of replication components that were mainly vertically inherited, or to a variable and highly divergent shell of extra copies that have likely arisen from integrative elements. This suggests that replication proteins are frequently exchanged between extrachromosomal elements and cellular genomes. Our study allowed clarifying the history that shaped this key cellular process (ancestral components, horizontal gene transfers, and gene losses), providing important evolutionary and functional information. Finally, our precise identification of core components permitted to show that the phylogenetic signal carried by DNA replication is highly consistent with that harbored by two other key informational machineries (translation and transcription), strengthening the existence of a robust organismal tree for the Archaea.
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Affiliation(s)
- Kasie Raymann
- Département de Microbiologie, Institut Pasteur, Unité Biologie Moléculaire du Gene chez les Extrêmophiles, Paris, France
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50
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Guy L, Saw JH, Ettema TJG. The archaeal legacy of eukaryotes: a phylogenomic perspective. Cold Spring Harb Perspect Biol 2014; 6:a016022. [PMID: 24993577 DOI: 10.1101/cshperspect.a016022] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
The origin of the eukaryotic cell can be regarded as one of the hallmarks in the history of life on our planet. The apparent genomic chimerism in eukaryotic genomes is currently best explained by invoking a cellular fusion at the root of the eukaryotes that involves one archaeal and one or more bacterial components. Here, we use a phylogenomics approach to reevaluate the evolutionary affiliation between Archaea and eukaryotes, and provide further support for scenarios in which the nuclear lineage in eukaryotes emerged from within the archaeal radiation, displaying a strong phylogenetic affiliation with, or even within, the archaeal TACK superphylum. Further taxonomic sampling of archaeal genomes in this superphylum will certainly provide a better resolution in the events that have been instrumental for the emergence of the eukaryotic lineage.
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Affiliation(s)
- Lionel Guy
- Department of Cell and Molecular Biology, Science for Life Laboratory, Uppsala University, SE-75123, Uppsala, Sweden
| | - Jimmy H Saw
- Department of Cell and Molecular Biology, Science for Life Laboratory, Uppsala University, SE-75123, Uppsala, Sweden
| | - Thijs J G Ettema
- Department of Cell and Molecular Biology, Science for Life Laboratory, Uppsala University, SE-75123, Uppsala, Sweden
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