51
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Cenci U, Moog D, Curtis BA, Tanifuji G, Eme L, Lukeš J, Archibald JM. Heme pathway evolution in kinetoplastid protists. BMC Evol Biol 2016; 16:109. [PMID: 27193376 PMCID: PMC4870792 DOI: 10.1186/s12862-016-0664-6] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2016] [Accepted: 04/21/2016] [Indexed: 01/09/2023] Open
Abstract
Background Kinetoplastea is a diverse protist lineage composed of several of the most successful parasites on Earth, organisms whose metabolisms have coevolved with those of the organisms they infect. Parasitic kinetoplastids have emerged from free-living, non-pathogenic ancestors on multiple occasions during the evolutionary history of the group. Interestingly, in both parasitic and free-living kinetoplastids, the heme pathway—a core metabolic pathway in a wide range of organisms—is incomplete or entirely absent. Indeed, Kinetoplastea investigated thus far seem to bypass the need for heme biosynthesis by acquiring heme or intermediate metabolites directly from their environment. Results Here we report the existence of a near-complete heme biosynthetic pathway in Perkinsela spp., kinetoplastids that live as obligate endosymbionts inside amoebozoans belonging to the genus Paramoeba/Neoparamoeba. We also use phylogenetic analysis to infer the evolution of the heme pathway in Kinetoplastea. Conclusion We show that Perkinsela spp. is a deep-branching kinetoplastid lineage, and that lateral gene transfer has played a role in the evolution of heme biosynthesis in Perkinsela spp. and other Kinetoplastea. We also discuss the significance of the presence of seven of eight heme pathway genes in the Perkinsela genome as it relates to its endosymbiotic relationship with Paramoeba. Electronic supplementary material The online version of this article (doi:10.1186/s12862-016-0664-6) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Ugo Cenci
- Department of Biochemistry and Molecular Biology, Dalhousie University, Halifax, Canada.,Centre for Comparative Genomics and Evolutionary Bioinformatics, Halifax, Nova Scotia, Canada
| | - Daniel Moog
- Department of Biochemistry and Molecular Biology, Dalhousie University, Halifax, Canada.,Centre for Comparative Genomics and Evolutionary Bioinformatics, Halifax, Nova Scotia, Canada
| | - Bruce A Curtis
- Department of Biochemistry and Molecular Biology, Dalhousie University, Halifax, Canada.,Centre for Comparative Genomics and Evolutionary Bioinformatics, Halifax, Nova Scotia, Canada
| | - Goro Tanifuji
- Faculty of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Japan
| | - Laura Eme
- Department of Biochemistry and Molecular Biology, Dalhousie University, Halifax, Canada.,Centre for Comparative Genomics and Evolutionary Bioinformatics, Halifax, Nova Scotia, Canada
| | - Julius Lukeš
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, and Faculty of Sciences, University of South Bohemia, České Budӗjovice, Czech Republic.,Canadian Institute for Advanced Research, Toronto, Canada
| | - John M Archibald
- Department of Biochemistry and Molecular Biology, Dalhousie University, Halifax, Canada. .,Centre for Comparative Genomics and Evolutionary Bioinformatics, Halifax, Nova Scotia, Canada. .,Canadian Institute for Advanced Research, Toronto, Canada.
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Abstract
The tree of life is one of the most important organizing principles in biology(1). Gene surveys suggest the existence of an enormous number of branches(2), but even an approximation of the full scale of the tree has remained elusive. Recent depictions of the tree of life have focused either on the nature of deep evolutionary relationships(3-5) or on the known, well-classified diversity of life with an emphasis on eukaryotes(6). These approaches overlook the dramatic change in our understanding of life's diversity resulting from genomic sampling of previously unexamined environments. New methods to generate genome sequences illuminate the identity of organisms and their metabolic capacities, placing them in community and ecosystem contexts(7,8). Here, we use new genomic data from over 1,000 uncultivated and little known organisms, together with published sequences, to infer a dramatically expanded version of the tree of life, with Bacteria, Archaea and Eukarya included. The depiction is both a global overview and a snapshot of the diversity within each major lineage. The results reveal the dominance of bacterial diversification and underline the importance of organisms lacking isolated representatives, with substantial evolution concentrated in a major radiation of such organisms. This tree highlights major lineages currently underrepresented in biogeochemical models and identifies radiations that are probably important for future evolutionary analyses.
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Del Campo J, Guillou L, Hehenberger E, Logares R, López-García P, Massana R. Ecological and evolutionary significance of novel protist lineages. Eur J Protistol 2016; 55:4-11. [PMID: 26996654 DOI: 10.1016/j.ejop.2016.02.002] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2015] [Revised: 01/23/2016] [Accepted: 02/12/2016] [Indexed: 01/12/2023]
Abstract
Environmental molecular surveys targeting protist diversity have unveiled novel and uncultured lineages in a variety of ecosystems, ranging from completely new high-rank lineages, to new taxa moderately related to previously described organisms. The ecological roles of some of these novel taxa have been studied, showing that in certain habitats they may be responsible for critical environmental processes. Moreover, from an evolutionary perspective they still need to be included in a more accurate and wider understanding of the eukaryotic tree of life. These seminal discoveries promoted the development and use of a wide range of more in-depth culture-independent approaches to access this diversity, from metabarcoding and metagenomics to single cell genomics and FISH. Nonetheless, culturing using classical or innovative approaches is also essential to better characterize this new diversity. Ecologists and evolutionary biologists now face the challenge of apprehending the significance of this new diversity within the eukaryotic tree of life.
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Affiliation(s)
- Javier Del Campo
- Department of Botany, University of British Columbia, Vancouver, Canada; Department of Marine Biology and Oceanography, Institut de Ciències del Mar (CSIC), Barcelona, Catalonia, Spain.
| | - Laure Guillou
- Sorbonne Universités, UPMC Univ. Paris 6, CNRS, Adaptation et Diversité en Milieu Marin (UMR 7144), équipe DIPO, Station Biologique de Roscoff, 29688 Roscoff, France
| | | | - Ramiro Logares
- Department of Marine Biology and Oceanography, Institut de Ciències del Mar (CSIC), Barcelona, Catalonia, Spain
| | - Purificación López-García
- Ecologie Systématique Evolution, CNRS, Université Paris-Sud, AgroParisTech, Université Paris-Saclay, 91400 Orsay, France
| | - Ramon Massana
- Department of Marine Biology and Oceanography, Institut de Ciències del Mar (CSIC), Barcelona, Catalonia, Spain
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54
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Kamikawa R, Shiratori T, Ishida KI, Miyashita H, Roger AJ. Group II Intron-Mediated Trans-Splicing in the Gene-Rich Mitochondrial Genome of an Enigmatic Eukaryote, Diphylleia rotans. Genome Biol Evol 2016; 8:458-66. [PMID: 26833505 PMCID: PMC4779616 DOI: 10.1093/gbe/evw011] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Although mitochondria have evolved from a single endosymbiotic event, present day mitochondria of diverse eukaryotes display a great range of genome structures, content and features. Group I and group II introns are two features that are distributed broadly but patchily in mitochondrial genomes across branches of the tree of eukaryotes. While group I intron-mediated trans-splicing has been reported from some lineages distantly related to each other, findings of group II intron-mediated trans-splicing has been restricted to members of the Chloroplastida. In this study, we found the mitochondrial genome of the unicellular eukaryote Diphylleia rotans possesses currently the second largest gene repertoire. On the basis of a probable phylogenetic position of Diphylleia, which is located within Amorphea, current mosaic gene distribution in Amorphea must invoke parallel gene losses from mitochondrial genomes during evolution. Most notably, although the cytochrome c oxidase subunit (cox) 1 gene was split into four pieces which located at a distance to each other, we confirmed that a single mature mRNA that covered the entire coding region could be generated by group II intron-mediated trans-splicing. This is the first example of group II intron-mediated trans-splicing outside Chloroplastida. Similar trans-splicing mechanisms likely work for bipartitely split cox2 and nad3 genes to generate single mature mRNAs. We finally discuss origin and evolution of this type of trans-splicing in D. rotans as well as in eukaryotes.
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Affiliation(s)
- Ryoma Kamikawa
- Graduate School of Human and Environmental Studies, Kyoto University, Japan Graduate School of Global Environmental Studies, Kyoto University, Japan
| | - Takashi Shiratori
- Graduate School of Life and Environmental Sciences, University of Tsukuba, Ibaraki, Japan
| | - Ken-Ichiro Ishida
- Faculty of Life and Environmental Sciences, University of Tsukuba, Ibaraki, Japan
| | - Hideaki Miyashita
- Graduate School of Human and Environmental Studies, Kyoto University, Japan Graduate School of Global Environmental Studies, Kyoto University, Japan
| | - Andrew J Roger
- Centre for Comparative Genomics and Evolutionary Bioinformatics, Department of Biochemistry and Molecular Biology, Dalhousie University, Halifax, Nova Scotia, Canada Program in Integrated Microbial Biodiversity, Canadian Institute for Advanced Research, Halifax, Nova Scotia, Canada
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55
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Burki F, Kaplan M, Tikhonenkov DV, Zlatogursky V, Minh BQ, Radaykina LV, Smirnov A, Mylnikov AP, Keeling PJ. Untangling the early diversification of eukaryotes: a phylogenomic study of the evolutionary origins of Centrohelida, Haptophyta and Cryptista. Proc Biol Sci 2016; 283:rspb.2015.2802. [PMID: 26817772 DOI: 10.1098/rspb.2015.2802] [Citation(s) in RCA: 194] [Impact Index Per Article: 24.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2015] [Accepted: 12/22/2015] [Indexed: 12/16/2022] Open
Abstract
Assembling the global eukaryotic tree of life has long been a major effort of Biology. In recent years, pushed by the new availability of genome-scale data for microbial eukaryotes, it has become possible to revisit many evolutionary enigmas. However, some of the most ancient nodes, which are essential for inferring a stable tree, have remained highly controversial. Among other reasons, the lack of adequate genomic datasets for key taxa has prevented the robust reconstruction of early diversification events. In this context, the centrohelid heliozoans are particularly relevant for reconstructing the tree of eukaryotes because they represent one of the last substantial groups that was missing large and diverse genomic data. Here, we filled this gap by sequencing high-quality transcriptomes for four centrohelid lineages, each corresponding to a different family. Combining these new data with a broad eukaryotic sampling, we produced a gene-rich taxon-rich phylogenomic dataset that enabled us to refine the structure of the tree. Specifically, we show that (i) centrohelids relate to haptophytes, confirming Haptista; (ii) Haptista relates to SAR; (iii) Cryptista share strong affinity with Archaeplastida; and (iv) Haptista + SAR is sister to Cryptista + Archaeplastida. The implications of this topology are discussed in the broader context of plastid evolution.
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Affiliation(s)
- Fabien Burki
- Department of Botany, University of British Columbia, Vancouver, British Columbia, Canada
| | - Maia Kaplan
- Department of Botany, University of British Columbia, Vancouver, British Columbia, Canada
| | - Denis V Tikhonenkov
- Department of Botany, University of British Columbia, Vancouver, British Columbia, Canada Institute for Biology of Inland Waters, Russian Academy of Sciences, Borok, Russia
| | - Vasily Zlatogursky
- Department of Invertebrate Zoology, St Petersburg State University, St Petersburg, Russia
| | - Bui Quang Minh
- Center for Integrative Bioinformatics, Max F. Perutz Laboratories, University of Vienna, Medical University of Vienna, Vienna, Austria
| | - Liudmila V Radaykina
- Institute for Biology of Inland Waters, Russian Academy of Sciences, Borok, Russia
| | - Alexey Smirnov
- Department of Invertebrate Zoology, St Petersburg State University, St Petersburg, Russia
| | - Alexander P Mylnikov
- Institute for Biology of Inland Waters, Russian Academy of Sciences, Borok, Russia
| | - Patrick J Keeling
- Department of Botany, University of British Columbia, Vancouver, British Columbia, Canada Canadian Institute for Advanced Research, Integrated Microbial Biodiversity Program, Toronto, Ontario, Canada
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56
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Cavalier-Smith T, Chao EE, Lewis R. Multiple origins of Heliozoa from flagellate ancestors: New cryptist subphylum Corbihelia, superclass Corbistoma, and monophyly of Haptista, Cryptista, Hacrobia and Chromista. Mol Phylogenet Evol 2015; 93:331-62. [DOI: 10.1016/j.ympev.2015.07.004] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2015] [Revised: 06/25/2015] [Accepted: 07/10/2015] [Indexed: 11/30/2022]
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57
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Gawryluk RM, Eme L, Roger AJ. Gene fusion, fission, lateral transfer, and loss: Not-so-rare events in the evolution of eukaryotic ATP citrate lyase. Mol Phylogenet Evol 2015; 91:12-6. [DOI: 10.1016/j.ympev.2015.05.010] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2014] [Revised: 05/07/2015] [Accepted: 05/11/2015] [Indexed: 10/23/2022]
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58
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Stairs CW, Leger MM, Roger AJ. Diversity and origins of anaerobic metabolism in mitochondria and related organelles. Philos Trans R Soc Lond B Biol Sci 2015; 370:20140326. [PMID: 26323757 PMCID: PMC4571565 DOI: 10.1098/rstb.2014.0326] [Citation(s) in RCA: 97] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/15/2015] [Indexed: 12/27/2022] Open
Abstract
Across the diversity of life, organisms have evolved different strategies to thrive in hypoxic environments, and microbial eukaryotes (protists) are no exception. Protists that experience hypoxia often possess metabolically distinct mitochondria called mitochondrion-related organelles (MROs). While there are some common metabolic features shared between the MROs of distantly related protists, these organelles have evolved independently multiple times across the breadth of eukaryotic diversity. Until recently, much of our knowledge regarding the metabolic potential of different MROs was limited to studies in parasitic lineages. Over the past decade, deep-sequencing studies of free-living anaerobic protists have revealed novel configurations of metabolic pathways that have been co-opted for life in low oxygen environments. Here, we provide recent examples of anaerobic metabolism in the MROs of free-living protists and their parasitic relatives. Additionally, we outline evolutionary scenarios to explain the origins of these anaerobic pathways in eukaryotes.
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Affiliation(s)
- Courtney W Stairs
- Centre for Comparative Genomics and Evolutionary Bioinformatics, Department of Biochemistry and Molecular Biology, Dalhousie University, Sir Charles Tupper Medical Building, 5850 College Street, PO Box 15000, Halifax, Nova Scotia, Canada B3H 4R2
| | - Michelle M Leger
- Centre for Comparative Genomics and Evolutionary Bioinformatics, Department of Biochemistry and Molecular Biology, Dalhousie University, Sir Charles Tupper Medical Building, 5850 College Street, PO Box 15000, Halifax, Nova Scotia, Canada B3H 4R2
| | - Andrew J Roger
- Centre for Comparative Genomics and Evolutionary Bioinformatics, Department of Biochemistry and Molecular Biology, Dalhousie University, Sir Charles Tupper Medical Building, 5850 College Street, PO Box 15000, Halifax, Nova Scotia, Canada B3H 4R2
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59
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Lartillot N. Probabilistic models of eukaryotic evolution: time for integration. Philos Trans R Soc Lond B Biol Sci 2015; 370:20140338. [PMID: 26323768 PMCID: PMC4571576 DOI: 10.1098/rstb.2014.0338] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/03/2015] [Indexed: 11/12/2022] Open
Abstract
In spite of substantial work and recent progress, a global and fully resolved picture of the macroevolutionary history of eukaryotes is still under construction. This concerns not only the phylogenetic relations among major groups, but also the general characteristics of the underlying macroevolutionary processes, including the patterns of gene family evolution associated with endosymbioses, as well as their impact on the sequence evolutionary process. All these questions raise formidable methodological challenges, calling for a more powerful statistical paradigm. In this direction, model-based probabilistic approaches have played an increasingly important role. In particular, improved models of sequence evolution accounting for heterogeneities across sites and across lineages have led to significant, although insufficient, improvement in phylogenetic accuracy. More recently, one main trend has been to move away from simple parametric models and stepwise approaches, towards integrative models explicitly considering the intricate interplay between multiple levels of macroevolutionary processes. Such integrative models are in their infancy, and their application to the phylogeny of eukaryotes still requires substantial improvement of the underlying models, as well as additional computational developments.
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Affiliation(s)
- Nicolas Lartillot
- Laboratoire de Biométrie et Biologie Evolutive, UMR CNRS 5558, Université Claude Bernard Lyon 1, F-69622 Villeurbanne Cedex, France
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60
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Torruella G, de Mendoza A, Grau-Bové X, Antó M, Chaplin MA, del Campo J, Eme L, Pérez-Cordón G, Whipps CM, Nichols KM, Paley R, Roger AJ, Sitjà-Bobadilla A, Donachie S, Ruiz-Trillo I. Phylogenomics Reveals Convergent Evolution of Lifestyles in Close Relatives of Animals and Fungi. Curr Biol 2015; 25:2404-10. [PMID: 26365255 DOI: 10.1016/j.cub.2015.07.053] [Citation(s) in RCA: 121] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2014] [Revised: 06/30/2015] [Accepted: 07/22/2015] [Indexed: 11/28/2022]
Abstract
The Opisthokonta are a eukaryotic supergroup divided in two main lineages: animals and related protistan taxa, and fungi and their allies [1, 2]. There is a great diversity of lifestyles and morphologies among unicellular opisthokonts, from free-living phagotrophic flagellated bacterivores and filopodiated amoebas to cell-walled osmotrophic parasites and saprotrophs. However, these characteristics do not group into monophyletic assemblages, suggesting rampant convergent evolution within Opisthokonta. To test this hypothesis, we assembled a new phylogenomic dataset via sequencing 12 new strains of protists. Phylogenetic relationships among opisthokonts revealed independent origins of filopodiated amoebas in two lineages, one related to fungi and the other to animals. Moreover, we observed that specialized osmotrophic lifestyles evolved independently in fungi and protistan relatives of animals, indicating convergent evolution. We therefore analyzed the evolution of two key fungal characters in Opisthokonta, the flagellum and chitin synthases. Comparative analyses of the flagellar toolkit showed a previously unnoticed flagellar apparatus in two close relatives of animals, the filasterean Ministeria vibrans and Corallochytrium limacisporum. This implies that at least four different opisthokont lineages secondarily underwent flagellar simplification. Analysis of the evolutionary history of chitin synthases revealed significant expansions in both animals and fungi, and also in the Ichthyosporea and C. limacisporum, a group of cell-walled animal relatives. This indicates that the last opisthokont common ancestor had a complex toolkit of chitin synthases that was differentially retained in extant lineages. Thus, our data provide evidence for convergent evolution of specialized lifestyles in close relatives of animals and fungi from a generalist ancestor.
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Affiliation(s)
- Guifré Torruella
- Institut de Biologia Evolutiva (CSIC-Universitat Pompeu Fabra), Passeig Marítim de la Barceloneta 37-49, Barcelona 08003, Catalonia, Spain; Departament de Genètica, Universitat de Barcelona, Avinguda Diagonal 645, Barcelona 08028, Catalonia, Spain
| | - Alex de Mendoza
- Institut de Biologia Evolutiva (CSIC-Universitat Pompeu Fabra), Passeig Marítim de la Barceloneta 37-49, Barcelona 08003, Catalonia, Spain; Departament de Genètica, Universitat de Barcelona, Avinguda Diagonal 645, Barcelona 08028, Catalonia, Spain
| | - Xavier Grau-Bové
- Institut de Biologia Evolutiva (CSIC-Universitat Pompeu Fabra), Passeig Marítim de la Barceloneta 37-49, Barcelona 08003, Catalonia, Spain; Departament de Genètica, Universitat de Barcelona, Avinguda Diagonal 645, Barcelona 08028, Catalonia, Spain
| | - Meritxell Antó
- Institut de Biologia Evolutiva (CSIC-Universitat Pompeu Fabra), Passeig Marítim de la Barceloneta 37-49, Barcelona 08003, Catalonia, Spain
| | - Mark A Chaplin
- Department of Microbiology, University of Hawaii at Manoa, Snyder Hall, 2538 McCarthy Mall, Honolulu, HI 96822, USA
| | - Javier del Campo
- Institut de Biologia Evolutiva (CSIC-Universitat Pompeu Fabra), Passeig Marítim de la Barceloneta 37-49, Barcelona 08003, Catalonia, Spain; Department of Botany, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
| | - Laura Eme
- Department of Biochemistry and Molecular Biology, Centre for Comparative Genomics and Evolutionary Bioinformatics, Dalhousie University, Halifax, NS B3H 4R2, Canada
| | - Gregorio Pérez-Cordón
- Institute of Aquaculture Torre de la Sal, IATS-CSIC, Ribera de Cabanes s/n, Castelló 12595, Spain
| | - Christopher M Whipps
- Environmental and Forest Biology, State University of New York College of Environmental Science and Forestry (SUNY-ESF), Syracuse, NY 13210, USA
| | - Krista M Nichols
- Department of Biological Sciences, Purdue University, West Lafayette, IN 47907, USA; Conservation Biology Division, Northwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, 2725 Montlake Boulevard East, Seattle, WA 98112, USA
| | - Richard Paley
- Centre for Environment Fisheries and Aquaculture Science, Weymouth Laboratory, Barrack Road, The Nothe, Weymouth, Dorset DT4 8UB, UK
| | - Andrew J Roger
- Department of Biochemistry and Molecular Biology, Centre for Comparative Genomics and Evolutionary Bioinformatics, Dalhousie University, Halifax, NS B3H 4R2, Canada
| | - Ariadna Sitjà-Bobadilla
- Institute of Aquaculture Torre de la Sal, IATS-CSIC, Ribera de Cabanes s/n, Castelló 12595, Spain
| | - Stuart Donachie
- Department of Microbiology, University of Hawaii at Manoa, Snyder Hall, 2538 McCarthy Mall, Honolulu, HI 96822, USA
| | - Iñaki Ruiz-Trillo
- Institut de Biologia Evolutiva (CSIC-Universitat Pompeu Fabra), Passeig Marítim de la Barceloneta 37-49, Barcelona 08003, Catalonia, Spain; Departament de Genètica, Universitat de Barcelona, Avinguda Diagonal 645, Barcelona 08028, Catalonia, Spain; Institució Catalana de Recerca i Estudis Avançats (ICREA), Passeig Lluís Companys 23, Barcelona 08010, Catalonia, Spain.
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Phylogenomic analyses reveal subclass Scuticociliatia as the sister group of subclass Hymenostomatia within class Oligohymenophorea. Mol Phylogenet Evol 2015; 90:104-11. [DOI: 10.1016/j.ympev.2015.05.007] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2015] [Revised: 04/26/2015] [Accepted: 05/10/2015] [Indexed: 01/08/2023]
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62
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Speijer D, Lukeš J, Eliáš M. Sex is a ubiquitous, ancient, and inherent attribute of eukaryotic life. Proc Natl Acad Sci U S A 2015; 112:8827-34. [PMID: 26195746 PMCID: PMC4517231 DOI: 10.1073/pnas.1501725112] [Citation(s) in RCA: 171] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Sexual reproduction and clonality in eukaryotes are mostly seen as exclusive, the latter being rather exceptional. This view might be biased by focusing almost exclusively on metazoans. We analyze and discuss reproduction in the context of extant eukaryotic diversity, paying special attention to protists. We present results of phylogenetically extended searches for homologs of two proteins functioning in cell and nuclear fusion, respectively (HAP2 and GEX1), providing indirect evidence for these processes in several eukaryotic lineages where sex has not been observed yet. We argue that (i) the debate on the relative significance of sex and clonality in eukaryotes is confounded by not appropriately distinguishing multicellular and unicellular organisms; (ii) eukaryotic sex is extremely widespread and already present in the last eukaryotic common ancestor; and (iii) the general mode of existence of eukaryotes is best described by clonally propagating cell lines with episodic sex triggered by external or internal clues. However, important questions concern the relative longevity of true clonal species (i.e., species not able to return to sexual procreation anymore). Long-lived clonal species seem strikingly rare. We analyze their properties in the light of meiotic sex development from existing prokaryotic repair mechanisms. Based on these considerations, we speculate that eukaryotic sex likely developed as a cellular survival strategy, possibly in the context of internal reactive oxygen species stress generated by a (proto) mitochondrion. Thus, in the context of the symbiogenic model of eukaryotic origin, sex might directly result from the very evolutionary mode by which eukaryotic cells arose.
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Affiliation(s)
- Dave Speijer
- Department of Medical Biochemistry, Academic Medical Center, University of Amsterdam, 1105 AZ, Amsterdam, The Netherlands;
| | - Julius Lukeš
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, and Faculty of Sciences, University of South Bohemia, 370 05 České Budějovice, Czech Republic; Canadian Institute for Advanced Research, Toronto, ON, Canada M5G 1Z8
| | - Marek Eliáš
- Department of Biology and Ecology, University of Ostrava, 710 00 Ostrava, Czech Republic
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63
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The Evolutionary History of R2R3-MYB Proteins Across 50 Eukaryotes: New Insights Into Subfamily Classification and Expansion. Sci Rep 2015; 5:11037. [PMID: 26047035 PMCID: PMC4603784 DOI: 10.1038/srep11037] [Citation(s) in RCA: 74] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2014] [Accepted: 04/28/2015] [Indexed: 01/21/2023] Open
Abstract
R2R3-MYB proteins (2R-MYBs) are one of the main transcription factor families in higher plants. Since the evolutionary history of this gene family across the eukaryotic kingdom remains unknown, we performed a comparative analysis of 2R-MYBs from 50 major eukaryotic lineages, with particular emphasis on land plants. A total of 1548 candidates were identified among diverse taxonomic groups, which allowed for an updated classification of 73 highly conserved subfamilies, including many newly identified subfamilies. Our results revealed that the protein architectures, intron patterns, and sequence characteristics were remarkably conserved in each subfamily. At least four subfamilies were derived from early land plants, 10 evolved from spermatophytes, and 19 from angiosperms, demonstrating the diversity and preferential expansion of this gene family in land plants. Moreover, we determined that their remarkable expansion was mainly attributed to whole genome and segmental duplication, where duplicates were preferentially retained within certain subfamilies that shared three homologous intron patterns (a, b, and c) even though up to 12 types of patterns existed. Through our integrated distributions, sequence characteristics, and phylogenetic tree analyses, we confirm that 2R-MYBs are old and postulate that 3R-MYBs may be evolutionarily derived from 2R-MYBs via intragenic domain duplication.
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64
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Cavalier-Smith T. Mixed heterolobosean and novel gregarine lineage genes from culture ATCC 50646: Long-branch artefacts, not lateral gene transfer, distort α-tubulin phylogeny. Eur J Protistol 2015; 51:121-37. [DOI: 10.1016/j.ejop.2014.12.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2014] [Revised: 12/04/2014] [Accepted: 12/09/2014] [Indexed: 12/21/2022]
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65
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An ancestral bacterial division system is widespread in eukaryotic mitochondria. Proc Natl Acad Sci U S A 2015; 112:10239-46. [PMID: 25831547 DOI: 10.1073/pnas.1421392112] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Bacterial division initiates at the site of a contractile Z-ring composed of polymerized FtsZ. The location of the Z-ring in the cell is controlled by a system of three mutually antagonistic proteins, MinC, MinD, and MinE. Plastid division is also known to be dependent on homologs of these proteins, derived from the ancestral cyanobacterial endosymbiont that gave rise to plastids. In contrast, the mitochondria of model systems such as Saccharomyces cerevisiae, mammals, and Arabidopsis thaliana seem to have replaced the ancestral α-proteobacterial Min-based division machinery with host-derived dynamin-related proteins that form outer contractile rings. Here, we show that the mitochondrial division system of these model organisms is the exception, rather than the rule, for eukaryotes. We describe endosymbiont-derived, bacterial-like division systems comprising FtsZ and Min proteins in diverse less-studied eukaryote protistan lineages, including jakobid and heterolobosean excavates, a malawimonad, stramenopiles, amoebozoans, a breviate, and an apusomonad. For two of these taxa, the amoebozoan Dictyostelium purpureum and the jakobid Andalucia incarcerata, we confirm a mitochondrial localization of these proteins by their heterologous expression in Saccharomyces cerevisiae. The discovery of a proteobacterial-like division system in mitochondria of diverse eukaryotic lineages suggests that it was the ancestral feature of all eukaryotic mitochondria and has been supplanted by a host-derived system multiple times in distinct eukaryote lineages.
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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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Cavalier-Smith T, Fiore-Donno AM, Chao E, Kudryavtsev A, Berney C, Snell EA, Lewis R. Multigene phylogeny resolves deep branching of Amoebozoa. Mol Phylogenet Evol 2015; 83:293-304. [DOI: 10.1016/j.ympev.2014.08.011] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2014] [Revised: 08/02/2014] [Accepted: 08/11/2014] [Indexed: 10/24/2022]
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Cavalier-Smith T, Chao EE, Snell EA, Berney C, Fiore-Donno AM, Lewis R. Multigene eukaryote phylogeny reveals the likely protozoan ancestors of opisthokonts (animals, fungi, choanozoans) and Amoebozoa. Mol Phylogenet Evol 2014; 81:71-85. [DOI: 10.1016/j.ympev.2014.08.012] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2014] [Revised: 08/02/2014] [Accepted: 08/11/2014] [Indexed: 01/12/2023]
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Cavalier-Smith T. Gregarine site-heterogeneous 18S rDNA trees, revision of gregarine higher classification, and the evolutionary diversification of Sporozoa. Eur J Protistol 2014; 50:472-95. [DOI: 10.1016/j.ejop.2014.07.002] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2014] [Revised: 07/19/2014] [Accepted: 07/21/2014] [Indexed: 10/25/2022]
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Maguire F, Henriquez FL, Leonard G, Dacks JB, Brown MW, Richards TA. Complex patterns of gene fission in the eukaryotic folate biosynthesis pathway. Genome Biol Evol 2014; 6:2709-20. [PMID: 25252772 PMCID: PMC4224340 DOI: 10.1093/gbe/evu213] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Shared derived genomic characters can be useful for polarizing phylogenetic relationships, for example, gene fusions have been used to identify deep-branching relationships in the eukaryotes. Here, we report the evolutionary analysis of a three-gene fusion of folB, folK, and folP, which encode enzymes that catalyze consecutive steps in de novo folate biosynthesis. The folK-folP fusion was found across the eukaryotes and a sparse collection of prokaryotes. This suggests an ancient derivation with a number of gene losses in the eukaryotes potentially as a consequence of adaptation to heterotrophic lifestyles. In contrast, the folB-folK-folP gene is specific to a mosaic collection of Amorphea taxa (a group encompassing: Amoebozoa, Apusomonadida, Breviatea, and Opisthokonta). Next, we investigated the stability of this character. We identified numerous gene losses and a total of nine gene fission events, either by break up of an open reading frame (four events identified) or loss of a component domain (five events identified). This indicates that this three gene fusion is highly labile. These data are consistent with a growing body of data indicating gene fission events occur at high relative rates. Accounting for these sources of homoplasy, our data suggest that the folB-folK-folP gene fusion was present in the last common ancestor of Amoebozoa and Opisthokonta but absent in the Metazoa including the human genome. Comparative genomic data of these genes provides an important resource for designing therapeutic strategies targeting the de novo folate biosynthesis pathway of a variety of eukaryotic pathogens such as Acanthamoeba castellanii.
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Affiliation(s)
- Finlay Maguire
- Department of Life Sciences, Natural History Museum, London, United Kingdom
| | - Fiona L Henriquez
- Infection and Microbiology Research Group, Institute of Biomedical and Environmental Health Research, School of Science, University of the West of Scotland, Paisley, Renfrewshire, United Kingdom
| | - Guy Leonard
- Biosciences, University of Exeter, Geoffrey Pope Building, Exeter, United Kingdom
| | - Joel B Dacks
- Department of Life Sciences, Natural History Museum, London, United Kingdom Department of Cell Biology, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Alberta, Canada
| | - Matthew W Brown
- Department of Biological Sciences, Mississippi State University
| | - Thomas A Richards
- Biosciences, University of Exeter, Geoffrey Pope Building, Exeter, United Kingdom Canadian Institute for Advanced Research, CIFAR Program in Integrated Microbial Biodiversity
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Large-scale phylogenomic analysis reveals the phylogenetic position of the problematic taxon Protocruzia and unravels the deep phylogenetic affinities of the ciliate lineages. Mol Phylogenet Evol 2014; 78:36-42. [DOI: 10.1016/j.ympev.2014.04.020] [Citation(s) in RCA: 65] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2013] [Revised: 03/18/2014] [Accepted: 04/18/2014] [Indexed: 11/19/2022]
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Pánek T, Simpson AG, Hampl V, Čepička I. Creneis carolina gen. et sp. nov. (Heterolobosea), a Novel Marine Anaerobic Protist with Strikingly Derived Morphology and Life Cycle. Protist 2014; 165:542-67. [DOI: 10.1016/j.protis.2014.05.005] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2014] [Revised: 05/05/2014] [Accepted: 05/28/2014] [Indexed: 11/29/2022]
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Eme L, Sharpe SC, Brown MW, Roger AJ. On the age of eukaryotes: evaluating evidence from fossils and molecular clocks. Cold Spring Harb Perspect Biol 2014; 6:6/8/a016139. [PMID: 25085908 DOI: 10.1101/cshperspect.a016139] [Citation(s) in RCA: 116] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Our understanding of the phylogenetic relationships among eukaryotic lineages has improved dramatically over the few past decades thanks to the development of sophisticated phylogenetic methods and models of evolution, in combination with the increasing availability of sequence data for a variety of eukaryotic lineages. Concurrently, efforts have been made to infer the age of major evolutionary events along the tree of eukaryotes using fossil-calibrated molecular clock-based methods. Here, we review the progress and pitfalls in estimating the age of the last eukaryotic common ancestor (LECA) and major lineages. After reviewing previous attempts to date deep eukaryote divergences, we present the results of a Bayesian relaxed-molecular clock analysis of a large dataset (159 proteins, 85 taxa) using 19 fossil calibrations. We show that for major eukaryote groups estimated dates of divergence, as well as their credible intervals, are heavily influenced by the relaxed molecular clock models and methods used, and by the nature and treatment of fossil calibrations. Whereas the estimated age of LECA varied widely, ranging from 1007 (943-1102) Ma to 1898 (1655-2094) Ma, all analyses suggested that the eukaryotic supergroups subsequently diverged rapidly (i.e., within 300 Ma of LECA). The extreme variability of these and previously published analyses preclude definitive conclusions regarding the age of major eukaryote clades at this time. As more reliable fossil data on eukaryotes from the Proterozoic become available and improvements are made in relaxed molecular clock modeling, we may be able to date the age of extant eukaryotes more precisely.
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Affiliation(s)
- Laura Eme
- Centre for Comparative Genomics and Evolutionary Bioinformatics, Department of Biochemistry and Molecular Biology, Dalhousie University, Halifax B3H 4R2, Canada
| | - Susan C Sharpe
- Centre for Comparative Genomics and Evolutionary Bioinformatics, Department of Biochemistry and Molecular Biology, Dalhousie University, Halifax B3H 4R2, Canada
| | - Matthew W Brown
- Centre for Comparative Genomics and Evolutionary Bioinformatics, Department of Biochemistry and Molecular Biology, Dalhousie University, Halifax B3H 4R2, Canada
| | - Andrew J Roger
- Centre for Comparative Genomics and Evolutionary Bioinformatics, Department of Biochemistry and Molecular Biology, Dalhousie University, Halifax B3H 4R2, Canada
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Stairs CW, Eme L, Brown MW, Mutsaers C, Susko E, Dellaire G, Soanes DM, van der Giezen M, Roger AJ. A SUF Fe-S cluster biogenesis system in the mitochondrion-related organelles of the anaerobic protist Pygsuia. Curr Biol 2014; 24:1176-86. [PMID: 24856215 DOI: 10.1016/j.cub.2014.04.033] [Citation(s) in RCA: 64] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2014] [Revised: 04/08/2014] [Accepted: 04/15/2014] [Indexed: 10/25/2022]
Abstract
BACKGROUND Many microbial eukaryotes have evolved anaerobic alternatives to mitochondria known as mitochondrion-related organelles (MROs). Yet, only a few of these have been experimentally investigated. Here we report an RNA-seq-based reconstruction of the MRO proteome of Pygsuia biforma, an anaerobic representative of an unexplored deep-branching eukaryotic lineage. RESULTS Pygsuia's MRO has a completely novel suite of functions, defying existing "function-based" organelle classifications. Most notable is the replacement of the mitochondrial iron-sulfur cluster machinery by an archaeal sulfur mobilization (SUF) system acquired via lateral gene transfer (LGT). Using immunolocalization in Pygsuia and heterologous expression in yeast, we show that the SUF system does indeed localize to the MRO. The Pygsuia MRO also possesses a unique assemblage of features, including: cardiolipin, phosphonolipid, amino acid, and fatty acid metabolism; a partial Kreb's cycle; a reduced respiratory chain; and a laterally acquired rhodoquinone (RQ) biosynthesis enzyme. The latter observation suggests that RQ is an electron carrier of a fumarate reductase-type complex II in this MRO. CONCLUSIONS The unique functional profile of this MRO underscores the tremendous plasticity of mitochondrial function within eukaryotes and showcases the role of LGT in forging metabolic mosaics of ancestral and newly acquired organellar pathways.
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Affiliation(s)
- Courtney W Stairs
- Centre for Comparative Genomics and Evolutionary Bioinformatics, Dalhousie University, Halifax, NS B3H 4R2, Canada; Department of Biochemistry and Molecular Biology, Dalhousie University, Halifax, NS B3H 4R2, Canada
| | - Laura Eme
- Centre for Comparative Genomics and Evolutionary Bioinformatics, Dalhousie University, Halifax, NS B3H 4R2, Canada; Department of Biochemistry and Molecular Biology, Dalhousie University, Halifax, NS B3H 4R2, Canada
| | - Matthew W Brown
- Department of Biological Sciences, Mississippi State University, Mississippi State, MS 39762, USA; The Institute for Genomics, Biocomputing, and Biotechnology, Mississippi State University, Mississippi State, MS 39762, USA
| | - Cornelis Mutsaers
- Centre for Comparative Genomics and Evolutionary Bioinformatics, Dalhousie University, Halifax, NS B3H 4R2, Canada; Department of Biochemistry and Molecular Biology, Dalhousie University, Halifax, NS B3H 4R2, Canada
| | - Edward Susko
- Centre for Comparative Genomics and Evolutionary Bioinformatics, Dalhousie University, Halifax, NS B3H 4R2, Canada; Department of Mathematics and Statistics, Dalhousie University, Halifax, NS B3H 4R2, Canada
| | - Graham Dellaire
- Department of Biochemistry and Molecular Biology, Dalhousie University, Halifax, NS B3H 4R2, Canada; Department of Pathology, Dalhousie University, Halifax, NS B3H 4R2, Canada
| | | | | | - Andrew J Roger
- Centre for Comparative Genomics and Evolutionary Bioinformatics, Dalhousie University, Halifax, NS B3H 4R2, Canada; Department of Biochemistry and Molecular Biology, Dalhousie University, Halifax, NS B3H 4R2, Canada.
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Nucleomorph and plastid genome sequences of the chlorarachniophyte Lotharella oceanica: convergent reductive evolution and frequent recombination in nucleomorph-bearing algae. BMC Genomics 2014; 15:374. [PMID: 24885563 PMCID: PMC4035089 DOI: 10.1186/1471-2164-15-374] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2014] [Accepted: 05/09/2014] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Nucleomorphs are residual nuclei derived from eukaryotic endosymbionts in chlorarachniophyte and cryptophyte algae. The endosymbionts that gave rise to nucleomorphs and plastids in these two algal groups were green and red algae, respectively. Despite their independent origin, the chlorarachniophyte and cryptophyte nucleomorph genomes share similar genomic features such as extreme size reduction and a three-chromosome architecture. This suggests that similar reductive evolutionary forces have acted to shape the nucleomorph genomes in the two groups. Thus far, however, only a single chlorarachniophyte nucleomorph and plastid genome has been sequenced, making broad evolutionary inferences within the chlorarachniophytes and between chlorarachniophytes and cryptophytes difficult. We have sequenced the nucleomorph and plastid genomes of the chlorarachniophyte Lotharella oceanica in order to gain insight into nucleomorph and plastid genome diversity and evolution. RESULTS The L. oceanica nucleomorph genome was found to consist of three linear chromosomes totaling ~610 kilobase pairs (kbp), much larger than the 373 kbp nucleomorph genome of the model chlorarachniophyte Bigelowiella natans. The L. oceanica plastid genome is 71 kbp in size, similar to that of B. natans. Unexpectedly long (~35 kbp) sub-telomeric repeat regions were identified in the L. oceanica nucleomorph genome; internal multi-copy regions were also detected. Gene content analyses revealed that nucleomorph house-keeping genes and spliceosomal intron positions are well conserved between the L. oceanica and B. natans nucleomorph genomes. More broadly, gene retention patterns were found to be similar between nucleomorph genomes in chlorarachniophytes and cryptophytes. Chlorarachniophyte plastid genomes showed near identical protein coding gene complements as well as a high level of synteny. CONCLUSIONS We have provided insight into the process of nucleomorph genome evolution by elucidating the fine-scale dynamics of sub-telomeric repeat regions. Homologous recombination at the chromosome ends appears to be frequent, serving to expand and contract nucleomorph genome size. The main factor influencing nucleomorph genome size variation between different chlorarachniophyte species appears to be expansion-contraction of these telomere-associated repeats rather than changes in the number of unique protein coding genes. The dynamic nature of chlorarachniophyte nucleomorph genomes lies in stark contrast to their plastid genomes, which appear to be highly stable in terms of gene content and synteny.
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Burki F. The eukaryotic tree of life from a global phylogenomic perspective. Cold Spring Harb Perspect Biol 2014; 6:a016147. [PMID: 24789819 DOI: 10.1101/cshperspect.a016147] [Citation(s) in RCA: 206] [Impact Index Per Article: 20.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Molecular phylogenetics has revolutionized our knowledge of the eukaryotic tree of life. With the advent of genomics, a new discipline of phylogenetics has emerged: phylogenomics. This method uses large alignments of tens to hundreds of genes to reconstruct evolutionary histories. This approach has led to the resolution of ancient and contentious relationships, notably between the building blocks of the tree (the supergroups), and allowed to place in the tree enigmatic yet important protist lineages for understanding eukaryote evolution. Here, I discuss the pros and cons of phylogenomics and review the eukaryotic supergroups in light of earlier work that laid the foundation for the current view of the tree, including the position of the root. I conclude by presenting a picture of eukaryote evolution, summarizing the most recent progress in assembling the global tree.
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Affiliation(s)
- Fabien Burki
- Canadian Institute for Advanced Research, Department of Botany, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada
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