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Dai GZ, Song WY, Xu HF, Tu M, Yu C, Li ZK, Shang JL, Jin CL, Ding CS, Zuo LZ, Liu YR, Yan WW, Zang SS, Liu K, Zhang Z, Bock R, Qiu BS. Hypothetical chloroplast reading frame 51 encodes a photosystem I assembly factor in cyanobacteria. THE PLANT CELL 2024; 36:1844-1867. [PMID: 38146915 PMCID: PMC11062458 DOI: 10.1093/plcell/koad330] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2023] [Revised: 09/29/2023] [Accepted: 12/20/2023] [Indexed: 12/27/2023]
Abstract
Hypothetical chloroplast open reading frames (ycfs) are putative genes in the plastid genomes of photosynthetic eukaryotes. Many ycfs are also conserved in the genomes of cyanobacteria, the presumptive ancestors of present-day chloroplasts. The functions of many ycfs are still unknown. Here, we generated knock-out mutants for ycf51 (sll1702) in the cyanobacterium Synechocystis sp. PCC 6803. The mutants showed reduced photoautotrophic growth due to impaired electron transport between photosystem II (PSII) and PSI. This phenotype results from greatly reduced PSI content in the ycf51 mutant. The ycf51 disruption had little effect on the transcription of genes encoding photosynthetic complex components and the stabilization of the PSI complex. In vitro and in vivo analyses demonstrated that Ycf51 cooperates with PSI assembly factor Ycf3 to mediate PSI assembly. Furthermore, Ycf51 interacts with the PSI subunit PsaC. Together with its specific localization in the thylakoid membrane and the stromal exposure of its hydrophilic region, our data suggest that Ycf51 is involved in PSI complex assembly. Ycf51 is conserved in all sequenced cyanobacteria, including the earliest branching cyanobacteria of the Gloeobacter genus, and is also present in the plastid genomes of glaucophytes. However, Ycf51 has been lost from other photosynthetic eukaryotic lineages. Thus, Ycf51 is a PSI assembly factor that has been functionally replaced during the evolution of oxygenic photosynthetic eukaryotes.
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Affiliation(s)
- Guo-Zheng Dai
- School of Life Sciences, and Hubei Key Laboratory of Genetic Regulation and Integrative Biology, Central China Normal University, Wuhan 430079, Hubei, PR China
| | - Wei-Yu Song
- School of Life Sciences, and Hubei Key Laboratory of Genetic Regulation and Integrative Biology, Central China Normal University, Wuhan 430079, Hubei, PR China
| | - Hai-Feng Xu
- School of Life Sciences, and Hubei Key Laboratory of Genetic Regulation and Integrative Biology, Central China Normal University, Wuhan 430079, Hubei, PR China
| | - Miao Tu
- School of Life Sciences, and Hubei Key Laboratory of Genetic Regulation and Integrative Biology, Central China Normal University, Wuhan 430079, Hubei, PR China
| | - Chen Yu
- School of Life Sciences, and Hubei Key Laboratory of Genetic Regulation and Integrative Biology, Central China Normal University, Wuhan 430079, Hubei, PR China
| | - Zheng-Ke Li
- School of Life Sciences, and Hubei Key Laboratory of Genetic Regulation and Integrative Biology, Central China Normal University, Wuhan 430079, Hubei, PR China
| | - Jin-Long Shang
- School of Life Sciences, and Hubei Key Laboratory of Genetic Regulation and Integrative Biology, Central China Normal University, Wuhan 430079, Hubei, PR China
| | - Chun-Lei Jin
- School of Life Sciences, and Hubei Key Laboratory of Genetic Regulation and Integrative Biology, Central China Normal University, Wuhan 430079, Hubei, PR China
| | - Chao-Shun Ding
- School of Life Sciences, and Hubei Key Laboratory of Genetic Regulation and Integrative Biology, Central China Normal University, Wuhan 430079, Hubei, PR China
| | - Ling-Zi Zuo
- School of Life Sciences, and Hubei Key Laboratory of Genetic Regulation and Integrative Biology, Central China Normal University, Wuhan 430079, Hubei, PR China
| | - Yan-Ru Liu
- School of Life Sciences, and Hubei Key Laboratory of Genetic Regulation and Integrative Biology, Central China Normal University, Wuhan 430079, Hubei, PR China
| | - Wei-Wei Yan
- School of Life Sciences, and Hubei Key Laboratory of Genetic Regulation and Integrative Biology, Central China Normal University, Wuhan 430079, Hubei, PR China
| | - Sha-Sha Zang
- School of Life Sciences, and Hubei Key Laboratory of Genetic Regulation and Integrative Biology, Central China Normal University, Wuhan 430079, Hubei, PR China
| | - Ke Liu
- School of Life Sciences, and Hubei Key Laboratory of Genetic Regulation and Integrative Biology, Central China Normal University, Wuhan 430079, Hubei, PR China
| | - Zheng Zhang
- School of Life Sciences, and Hubei Key Laboratory of Genetic Regulation and Integrative Biology, Central China Normal University, Wuhan 430079, Hubei, PR China
| | - Ralph Bock
- Department III, Max-Planck-Institut für Molekulare Pflanzenphysiologie, D-14476 Potsdam-Golm, Germany
| | - Bao-Sheng Qiu
- School of Life Sciences, and Hubei Key Laboratory of Genetic Regulation and Integrative Biology, Central China Normal University, Wuhan 430079, Hubei, PR China
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2
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Falshaw R, Furneaux RH, Sims IM, Hinkley SFR, Kidgell JT, Bell TJ. Novel 4-O-β-d-xylopyranosyl-3,6-anhydro-l-galactopyranosyl disaccharide units in a polysaccharide from the red alga Pyrophyllon subtumens. Carbohydr Polym 2023; 318:121066. [PMID: 37479460 DOI: 10.1016/j.carbpol.2023.121066] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Revised: 05/21/2023] [Accepted: 05/24/2023] [Indexed: 07/23/2023]
Abstract
Thalli of the endemic epiphytic New Zealand red seaweed Pyrophyllon subtumens are known to contain a high level of xylose and a notable amount of arabinose but the extracted polysaccharide has not been characterised. The linkage/substitution of individual sugars within the water-soluble polysaccharide extract and various derivatives were determined by chemical and spectroscopic methods. No 3-linked sugars nor any d-galactose were found, which excluded agar-, carrageenan- or mixed 3-linked/4-linked β-d-xylan-type polysaccharides found in many other red macroalgae. Instead, the polysaccharide backbone contained predominantly 4-linked β-d-xylopyranosyl, 4-linked 3,6-anhydro-l-galactopyranosyl and 4-linked l-galactopyranosyl units. Some of each type of sugar were sulfated at various positions. Some xylosyl units were substituted at the 2- or 3-position with l-arabinosyl units. The polysaccharide is complex and likely contains a range of structures. However, partial sequencing was successfully used to recover and identify a novel disaccharide 4-O-d-xylopyranosyl-3,6-anhdydro-l-galactopyranose, which indicates a unique →4)-β-d-Xylp-(1 → 4)-3,6-anhydro-l-Galp-(1 → repeat unit in the polysaccharide.
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Affiliation(s)
- Ruth Falshaw
- Ferrier Research Institute, Victoria University of Wellington, PO Box 33-436, Petone 5046, New Zealand.
| | - Richard H Furneaux
- Ferrier Research Institute, Victoria University of Wellington, PO Box 33-436, Petone 5046, New Zealand.
| | - Ian M Sims
- Ferrier Research Institute, Victoria University of Wellington, PO Box 33-436, Petone 5046, New Zealand.
| | - Simon F R Hinkley
- Ferrier Research Institute, Victoria University of Wellington, PO Box 33-436, Petone 5046, New Zealand.
| | - Joel T Kidgell
- Ferrier Research Institute, Victoria University of Wellington, PO Box 33-436, Petone 5046, New Zealand.
| | - Tracey J Bell
- Ferrier Research Institute, Victoria University of Wellington, PO Box 33-436, Petone 5046, New Zealand.
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3
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Borg M, Krueger-Hadfield SA, Destombe C, Collén J, Lipinska A, Coelho SM. Red macroalgae in the genomic era. THE NEW PHYTOLOGIST 2023; 240:471-488. [PMID: 37649301 DOI: 10.1111/nph.19211] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2023] [Accepted: 07/24/2023] [Indexed: 09/01/2023]
Abstract
Rhodophyta (or red algae) are a diverse and species-rich group that forms one of three major lineages in the Archaeplastida, a eukaryotic supergroup whose plastids arose from a single primary endosymbiosis. Red algae are united by several features, such as relatively small intron-poor genomes and a lack of cytoskeletal structures associated with motility like flagella and centrioles, as well as a highly efficient photosynthetic capacity. Multicellular red algae (or macroalgae) are one of the earliest diverging eukaryotic lineages to have evolved complex multicellularity, yet despite their ecological, evolutionary, and commercial importance, they have remained a largely understudied group of organisms. Considering the increasing availability of red algal genome sequences, we present a broad overview of fundamental aspects of red macroalgal biology and posit on how this is expected to accelerate research in many domains of red algal biology in the coming years.
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Affiliation(s)
- Michael Borg
- Department of Algal Development and Evolution, Max Planck Institute for Biology, 72076, Tübingen, Germany
| | - Stacy A Krueger-Hadfield
- Department of Biology, The University of Alabama at Birmingham, Birmingham, AL, 35294, USA
- Virginia Institute of Marine Science Eastern Shore Laboratory, Wachapreague, VA, 23480, USA
| | - Christophe Destombe
- International Research Laboratory 3614 (IRL3614) - Evolutionary Biology and Ecology of Algae, Centre National de la Recherche Scientifique (CNRS), Sorbonne Université, Pontificia Universidad Católica de Chile, Universidad Austral de Chile, Roscoff, 29680, France
| | - Jonas Collén
- CNRS, Integrative Biology of Marine Models (LBI2M, UMR8227), Station Biologique de Roscoff, Sorbonne Université, Roscoff, 29680, France
| | - Agnieszka Lipinska
- Department of Algal Development and Evolution, Max Planck Institute for Biology, 72076, Tübingen, Germany
| | - Susana M Coelho
- Department of Algal Development and Evolution, Max Planck Institute for Biology, 72076, Tübingen, Germany
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4
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San MH, Kawamura Y, Kimura K, Witharana EP, Shimogiri T, Aye SS, Min TT, Aung C, Khaing MM, Nagano Y. Characterization and organelle genome sequencing of Pyropia species from Myanmar. Sci Rep 2023; 13:15677. [PMID: 37735516 PMCID: PMC10514050 DOI: 10.1038/s41598-023-42262-3] [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: 04/03/2023] [Accepted: 09/07/2023] [Indexed: 09/23/2023] Open
Abstract
Pyropia is a genus comprising red algae of the Bangiaceae family that is commonly found in intertidal zones worldwide. However, understanding of Pyropia species that are prone to tropical regions remains limited despite recent breakthroughs in genomic research. Within the realm of Pyropia species thriving in tropical regions, P. vietnamensis stands out as a widely recognized species. In this study, we aimed to investigate Pyropia species in the southwest coast of Myanmar using physiological and molecular approaches, culture-based analyses, chloroplast rbcL and nuclear SSU gene sequencing, and whole chloroplast and mitochondrial genome sequencing. Physiological analysis showed that the Myanmar samples were more heat-tolerant than their Japanese counterparts, including those of subtropical origin. Additionally, molecular characterization revealed that the Myanmar samples were closely related to P. vietnamensis from India. This study is the first to sequence the chloroplast and mitochondrial genomes of Pyropia species from tropical regions. A unique deletion event was observed within a ribosomal RNA gene cluster in the chloroplast genome of the studied Pyropia species, which is a deviation from the usual characteristics of most Pyropia species. This study improves current understanding of the physiological and molecular characteristics of this comparatively understudied Pyropia species that grows in tropical regions.
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Affiliation(s)
- Myat Htoo San
- The United Graduate School of Agricultural Sciences, Kagoshima University, Kagoshima, Japan.
- Analytical Research Center for Experimental Sciences, Saga University, Saga, Japan.
| | | | - Kei Kimura
- The United Graduate School of Agricultural Sciences, Kagoshima University, Kagoshima, Japan
- Faculty of Agriculture, Saga University, Saga, Japan
| | | | - Takeshi Shimogiri
- The United Graduate School of Agricultural Sciences, Kagoshima University, Kagoshima, Japan
- Faculty of Agriculture, Kagoshima University, Kagoshima, Japan
| | | | - Thu Thu Min
- Marine Science Department, Pathein University, Pathein, Myanmar
| | - Cherry Aung
- Marine Science Department, Myeik University, Myeik, Myanmar
| | | | - Yukio Nagano
- The United Graduate School of Agricultural Sciences, Kagoshima University, Kagoshima, Japan.
- Analytical Research Center for Experimental Sciences, Saga University, Saga, Japan.
- Graduate School of Advanced Health Science, Saga University, Saga, Japan.
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5
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Lang BF, Beck N, Prince S, Sarrasin M, Rioux P, Burger G. Mitochondrial genome annotation with MFannot: a critical analysis of gene identification and gene model prediction. FRONTIERS IN PLANT SCIENCE 2023; 14:1222186. [PMID: 37469769 PMCID: PMC10352661 DOI: 10.3389/fpls.2023.1222186] [Citation(s) in RCA: 20] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/13/2023] [Accepted: 06/15/2023] [Indexed: 07/21/2023]
Abstract
Compared to nuclear genomes, mitochondrial genomes (mitogenomes) are small and usually code for only a few dozen genes. Still, identifying genes and their structure can be challenging and time-consuming. Even automated tools for mitochondrial genome annotation often require manual analysis and curation by skilled experts. The most difficult steps are (i) the structural modelling of intron-containing genes; (ii) the identification and delineation of Group I and II introns; and (iii) the identification of moderately conserved, non-coding RNA (ncRNA) genes specifying 5S rRNAs, tmRNAs and RNase P RNAs. Additional challenges arise through genetic code evolution which can redefine the translational identity of both start and stop codons, thus obscuring protein-coding genes. Further, RNA editing can render gene identification difficult, if not impossible, without additional RNA sequence data. Current automated mito- and plastid-genome annotators are limited as they are typically tailored to specific eukaryotic groups. The MFannot annotator we developed is unique in its applicability to a broad taxonomic scope, its accuracy in gene model inference, and its capabilities in intron identification and classification. The pipeline leverages curated profile Hidden Markov Models (HMMs), covariance (CMs) and ERPIN models to better capture evolutionarily conserved signatures in the primary sequence (HMMs and CMs) as well as secondary structure (CMs and ERPIN). Here we formally describe MFannot, which has been available as a web-accessible service (https://megasun.bch.umontreal.ca/apps/mfannot/) to the research community for nearly 16 years. Further, we report its performance on particularly intron-rich mitogenomes and describe ongoing and future developments.
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Lee Y, Cho CH, Noh C, Yang JH, Park SI, Lee YM, West JA, Bhattacharya D, Jo K, Yoon HS. Origin of minicircular mitochondrial genomes in red algae. Nat Commun 2023; 14:3363. [PMID: 37291154 PMCID: PMC10250338 DOI: 10.1038/s41467-023-39084-2] [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: 12/14/2021] [Accepted: 05/30/2023] [Indexed: 06/10/2023] Open
Abstract
Eukaryotic organelle genomes are generally of conserved size and gene content within phylogenetic groups. However, significant variation in genome structure may occur. Here, we report that the Stylonematophyceae red algae contain multipartite circular mitochondrial genomes (i.e., minicircles) which encode one or two genes bounded by a specific cassette and a conserved constant region. These minicircles are visualized using fluorescence microscope and scanning electron microscope, proving the circularity. Mitochondrial gene sets are reduced in these highly divergent mitogenomes. Newly generated chromosome-level nuclear genome assembly of Rhodosorus marinus reveals that most mitochondrial ribosomal subunit genes are transferred to the nuclear genome. Hetero-concatemers that resulted from recombination between minicircles and unique gene inventory that is responsible for mitochondrial genome stability may explain how the transition from typical mitochondrial genome to minicircles occurs. Our results offer inspiration on minicircular organelle genome formation and highlight an extreme case of mitochondrial gene inventory reduction.
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Affiliation(s)
- Yongsung Lee
- Department of Biological Sciences, Sungkyunkwan University, Suwon, 16419, Korea
| | - Chung Hyun Cho
- Department of Biological Sciences, Sungkyunkwan University, Suwon, 16419, Korea
| | - Chanyoung Noh
- Department of Chemistry, Sogang University, Seoul, 04107, Korea
| | - Ji Hyun Yang
- Department of Biological Sciences, Sungkyunkwan University, Suwon, 16419, Korea
| | - Seung In Park
- Department of Biological Sciences, Sungkyunkwan University, Suwon, 16419, Korea
| | - Yu Min Lee
- Department of Biological Sciences, Sungkyunkwan University, Suwon, 16419, Korea
| | - John A West
- School of Biosciences 2, University of Melbourne, Parkville, Victoria, 3010, Australia
| | - Debashish Bhattacharya
- Department of Biochemistry and Microbiology, Rutgers University, New Brunswick, 08901, USA
| | - Kyubong Jo
- Department of Chemistry, Sogang University, Seoul, 04107, Korea.
| | - Hwan Su Yoon
- Department of Biological Sciences, Sungkyunkwan University, Suwon, 16419, Korea.
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7
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Barcytė D. Extremophilic red algae reordered. JOURNAL OF PHYCOLOGY 2023; 59:441-443. [PMID: 37313841 DOI: 10.1111/jpy.13328] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Affiliation(s)
- Dovilė Barcytė
- Department of Biology and Ecology, Faculty of Science, University of Ostrava, Chittussiho 10, 710 00, Ostrava, Czech Republic
- Okinawa Institute of Science and Technology, Okinawa, 904-0495, Japan
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8
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Barreto de Jesus P, de Mattos Lyra G, Zhang H, Toyota Fujii M, Nauer F, Marcos de Castro Nunes J, Davis CC, Cabral Oliveira M. Phylogenomics and taxon-rich phylogenies of new and historical specimens shed light on the systematics of Hypnea (Cystocloniaceae, Rhodophyta). Mol Phylogenet Evol 2023; 183:107752. [PMID: 36893930 DOI: 10.1016/j.ympev.2023.107752] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2022] [Revised: 02/17/2023] [Accepted: 03/02/2023] [Indexed: 03/09/2023]
Abstract
Cystocloniacae is a highly diverse family of Rhodophyta, including species of ecological and economic importance, whose phylogeny remains largely unresolved. Species delimitation is unclear, particularly in the most speciose genus, Hypnea, and cryptic diversity has been revealed by recent molecular assessments, especially in the tropics. Here, we carried out the first phylogenomic investigation of Cystocloniaceae, focused on the genus Hypnea, inferred from chloroplast and mitochondrial genomes including taxa sampled from new and historical collections. In this work, molecular synapomorphies (gene losses, InDels and gene inversions) were identified to better characterize clades in our congruent organellar phylogenies. We also present taxon-rich phylogenies based on plastid and mitochondrial markers. Molecular and morphological comparisons of historic collections with contemporary specimens revealed the need for taxonomic updates in Hypnea, the synonymization of H. marchantae to a later heterotypic synonym of H. cervicornis and the description of three new species: H. davisiana sp. nov., H. djamilae sp. nov. and H. evaristoae sp. nov.
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Affiliation(s)
- Priscila Barreto de Jesus
- Centro de Ciências Naturais e Humanas, Universidade Federal do ABC (CCNH - UFABC), Rua Arcturus 03, São Bernardo do Campo, São Paulo, 09606-070, Brazil; Departamento de Botânica, Instituto de Biociências, Universidade de São Paulo, Rua do Matão 277, São Paulo, São Paulo, 05508-090, Brazil.
| | - Goia de Mattos Lyra
- Programa de Pós-Graduação em Biodiversidade e Evolução, Instituto de Biologia, Universidade Federal da Bahia, Rua Barão de Jeremoabo, s/n, Salvador, Bahia, 40170-115, Brasil; Department of Organismic and Evolutionary Biology, Harvard University Herbaria, 22 Divinity Avenue, Cambridge Massachusetts 02138, USA; Laboratório de Algas Marinhas, Instituto de Biologia, Universidade Federal da Bahia, Rua Barão de Jeremoabo, s/n, Salvador Bahia 40170-115, Brasil
| | - Hongrui Zhang
- Department of Organismic and Evolutionary Biology, Harvard University Herbaria, 22 Divinity Avenue, Cambridge Massachusetts 02138, USA
| | - Mutue Toyota Fujii
- Núcleo de Conservação da Biodiversidade, Instituto de Pesquisas Ambientais, Av. Miguel Estefano 3687, 04301-902, São Paulo, Brazil
| | - Fabio Nauer
- Núcleo de Conservação da Biodiversidade, Instituto de Pesquisas Ambientais, Av. Miguel Estefano 3687, 04301-902, São Paulo, Brazil; Departamento de Botânica, Instituto de Biociências, Universidade de São Paulo, Rua do Matão 277, São Paulo, São Paulo, 05508-090, Brazil
| | - José Marcos de Castro Nunes
- Programa de Pós-Graduação em Biodiversidade e Evolução, Instituto de Biologia, Universidade Federal da Bahia, Rua Barão de Jeremoabo, s/n, Salvador, Bahia, 40170-115, Brasil; Laboratório de Algas Marinhas, Instituto de Biologia, Universidade Federal da Bahia, Rua Barão de Jeremoabo, s/n, Salvador Bahia 40170-115, Brasil
| | - Charles C Davis
- Department of Organismic and Evolutionary Biology, Harvard University Herbaria, 22 Divinity Avenue, Cambridge Massachusetts 02138, USA
| | - Mariana Cabral Oliveira
- Departamento de Botânica, Instituto de Biociências, Universidade de São Paulo, Rua do Matão 277, São Paulo, São Paulo, 05508-090, Brazil
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9
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Bowles AMC, Williamson CJ, Williams TA, Lenton TM, Donoghue PCJ. The origin and early evolution of plants. TRENDS IN PLANT SCIENCE 2023; 28:312-329. [PMID: 36328872 DOI: 10.1016/j.tplants.2022.09.009] [Citation(s) in RCA: 19] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Revised: 09/23/2022] [Accepted: 09/30/2022] [Indexed: 06/16/2023]
Abstract
Plant (archaeplastid) evolution has transformed the biosphere, but we are only now beginning to learn how this took place through comparative genomics, phylogenetics, and the fossil record. This has illuminated the phylogeny of Archaeplastida, Viridiplantae, and Streptophyta, and has resolved the evolution of key characters, genes, and genomes - revealing that many key innovations evolved long before the clades with which they have been casually associated. Molecular clock analyses estimate that Streptophyta and Viridiplantae emerged in the late Mesoproterozoic to late Neoproterozoic, whereas Archaeplastida emerged in the late-mid Palaeoproterozoic. Together, these insights inform on the coevolution of plants and the Earth system that transformed ecology and global biogeochemical cycles, increased weathering, and precipitated snowball Earth events, during which they would have been key to oxygen production and net primary productivity (NPP).
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Affiliation(s)
- Alexander M C Bowles
- School of Geographical Sciences, University of Bristol, University Road, Bristol BS8 1SS, UK; Bristol Palaeobiology Group, School of Biological Sciences and School of Earth Sciences, Life Sciences Building, University of Bristol, Bristol BS8 1TQ, UK.
| | | | - Tom A Williams
- Bristol Palaeobiology Group, School of Biological Sciences and School of Earth Sciences, Life Sciences Building, University of Bristol, Bristol BS8 1TQ, UK
| | - Timothy M Lenton
- Global Systems Institute, University of Exeter, Laver Building, North Park Road, Exeter EX4 4QE, UK
| | - Philip C J Donoghue
- Bristol Palaeobiology Group, School of Biological Sciences and School of Earth Sciences, Life Sciences Building, University of Bristol, Bristol BS8 1TQ, UK.
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10
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Zhang S, Yazaki E, Sakamoto H, Yamamoto H, Mizushima N. Evolutionary diversification of the autophagy-related ubiquitin-like conjugation systems. Autophagy 2022; 18:2969-2984. [PMID: 35427200 PMCID: PMC9673942 DOI: 10.1080/15548627.2022.2059168] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Two autophagy-related (ATG) ubiquitin-like conjugation systems, the ATG12 and ATG8 systems, play important roles in macroautophagy. While multiple duplications and losses of the ATG conjugation system proteins are found in different lineages, the extent to which the underlying systems diversified across eukaryotes is not fully understood. Here, in order to understand the evolution of the ATG conjugation systems, we constructed a transcriptome database consisting of 94 eukaryotic species covering major eukaryotic clades and systematically identified ATG conjugation system components. Both ATG10 and the C-terminal glycine of ATG12 are essential for the canonical ubiquitin-like conjugation of ATG12 and ATG5. However, loss of ATG10 or the C-terminal glycine of ATG12 occurred at least 16 times in a wide range of lineages, suggesting that possible covalent-to-non-covalent transition is not limited to the species that we previously reported such as Alveolata and some yeast species. Some species have only the ATG8 system (with conjugation enzymes) or only ATG8 (without conjugation enzymes). More than 10 species have ATG8 homologs without the conserved C-terminal glycine, and Tetrahymena has an ATG8 homolog with a predicted transmembrane domain, which may be able to anchor to the membrane independent of the ATG conjugation systems. We discuss the possibility that the ancestor of the ATG12 and ATG8 systems is more similar to ATG8. Overall, our study offers a whole picture of the evolution and diversity of the ATG conjugation systems among eukaryotes, and provides evidence that functional diversifications of the systems are more common than previously thought.Abbreviations: APEAR: ATG8-PE association region; ATG: autophagy-related; LIR: LC3-interacting region; NEDD8: neural precursor cell expressed, developmentally down-regulated gene 8; PE: phosphatidylethanolamine; SAMP: small archaeal modifier protein; SAR: Stramenopiles, Alveolata, and Rhizaria; SMC: structural maintenance of chromosomes; SUMO: small ubiquitin like modifier; TACK: Thaumarchaeota, Aigarchaeota, Crenarchaeota, and Korarchaeota; UBA: ubiquitin like modifier activating enzyme; UFM: ubiquitin fold modifier; URM: ubiquitin related modifier.
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Affiliation(s)
- Sidi Zhang
- Department of Biochemistry and Molecular Biology, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Euki Yazaki
- Department of Biochemistry and Molecular Biology, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan,Interdisciplinary Theoretical and Mathematical Sciences (iTHEMS), RIKEN, Saitama, Japan
| | - Hirokazu Sakamoto
- Department of Biochemistry and Molecular Biology, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan,Department of Biomedical Chemistry, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan,Department of Infection and Host Defense, Graduate School of Medicine, Chiba University, Chiba, Japan
| | - Hayashi Yamamoto
- Department of Biochemistry and Molecular Biology, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Noboru Mizushima
- Department of Biochemistry and Molecular Biology, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan,CONTACT Noboru Mizushima Department of Biochemistry and Molecular Biology, Graduate School of Medicine, The University of Tokyo, Tokyo113-0033, Japan
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11
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Life cycle and functional genomics of the unicellular red alga Galdieria for elucidating algal and plant evolution and industrial use. Proc Natl Acad Sci U S A 2022; 119:e2210665119. [PMID: 36194630 PMCID: PMC9565259 DOI: 10.1073/pnas.2210665119] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Sexual reproduction has not been observed in unicellular red algae and Glaucophyceae, early branching groups in Archaeplastida, in which red algae and Viridiplantae independently evolved multicellular sexual life cycles. The finding of sexual reproduction in the unicellular red alga Galdieria provides information on the missing link of life cycle evolution in Archaeplastida. In addition, the metabolic plasticity, the polyextremophilic features, a relatively small genome, transcriptome data for the diploid and haploid, and the genetic modification tools developed here provide a useful platform for understanding the evolution of Archaeplastida, photosynthesis, metabolism, and environmental adaptation. For biotechnological use of the information and tools of Galdieria, the newly found cell wall–less haploid makes cell disruption less energy/cost intensive than the cell-walled diploid. Sexual reproduction is widespread in eukaryotes; however, only asexual reproduction has been observed in unicellular red algae, including Galdieria, which branched early in Archaeplastida. Galdieria possesses a small genome; it is polyextremophile, grows either photoautotrophically, mixotrophically, or heterotrophically, and is being developed as an industrial source of vitamins and pigments because of its high biomass productivity. Here, we show that Galdieria exhibits a sexual life cycle, alternating between cell-walled diploid and cell wall–less haploid, and that both phases can proliferate asexually. The haploid can move over surfaces and undergo self-diploidization or generate heterozygous diploids through mating. Further, we prepared the whole genome and a comparative transcriptome dataset between the diploid and haploid and developed genetic tools for the stable gene expression, gene disruption, and selectable marker recycling system using the cell wall–less haploid. The BELL/KNOX and MADS-box transcription factors, which function in haploid-to-diploid transition and development in plants, are specifically expressed in the haploid and diploid, respectively, and are involved in the haploid-to-diploid transition in Galdieria, providing information on the missing link of the sexual life cycle evolution in Archaeplastida. Four actin genes are differently involved in motility of the haploid and cytokinesis in the diploid, both of which are myosin independent and likely reflect ancestral roles of actin. We have also generated photosynthesis-deficient mutants, such as blue-colored cells, which were depleted in chlorophyll and carotenoids, for industrial pigment production. These features of Galdieria facilitate the understanding of the evolution of algae and plants and the industrial use of microalgae.
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12
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Mettwally WS, Gamal AA, Shams El-Din NG, Hamdy AA. Biological activities and structural characterization of sulfated polysaccharide extracted from a newly Mediterranean Sea record Grateloupia gibbesii Harvey. BIOCATALYSIS AND AGRICULTURAL BIOTECHNOLOGY 2022. [DOI: 10.1016/j.bcab.2022.102487] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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13
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van Beveren F, Eme L, López-García P, Ciobanu M, Moreira D. Independent Size Expansions and Intron Proliferation in Red Algal Plastid and Mitochondrial Genomes. Genome Biol Evol 2022; 14:evac037. [PMID: 35289373 PMCID: PMC8995046 DOI: 10.1093/gbe/evac037] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/07/2022] [Indexed: 11/20/2022] Open
Abstract
Proliferation of selfish genetic elements has led to significant genome size expansion in plastid and mitochondrial genomes of various eukaryotic lineages. Within the red algae, such expansion events are only known in the plastid genomes of the Proteorhodophytina, a highly diverse group of mesophilic microalgae. By contrast, they have never been described in the much understudied red algal mitochondrial genomes. Therefore, it remains unclear how widespread such organellar genome expansion events are in this eukaryotic phylum. Here, we describe new mitochondrial and plastid genomes from 25 red algal species, thereby substantially expanding the amount of organellar sequence data available, especially for Proteorhodophytina, and show that genome expansions are common in this group. We confirm that large plastid genomes are limited to the classes Rhodellophyceae and Porphyridiophyceae, which, in part, are caused by lineage-specific expansion events. Independently expanded mitochondrial genomes-up to three times larger than typical red algal mitogenomes-occur across Proteorhodophytina classes and a large shift toward high GC content occurred in the Stylonematophyceae. Although intron proliferation is the main cause of plastid and mitochondrial genome expansion in red algae, we do not observe recent intron transfer between different organelles. Phylogenomic analyses of mitochondrial and plastid genes from our expanded taxon sampling yielded well-resolved phylogenies of red algae with strong support for the monophyly of Proteorhodophytina. Our work shows that organellar genomes followed different evolutionary dynamics across red algal lineages.
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Affiliation(s)
- Fabian van Beveren
- Ecologie Systématique Evolution, Centre National de la Recherche Scientifique—CNRS, Université Paris-Saclay, AgroParisTech, Orsay, France
| | - Laura Eme
- Ecologie Systématique Evolution, Centre National de la Recherche Scientifique—CNRS, Université Paris-Saclay, AgroParisTech, Orsay, France
| | - Purificación López-García
- Ecologie Systématique Evolution, Centre National de la Recherche Scientifique—CNRS, Université Paris-Saclay, AgroParisTech, Orsay, France
| | - Maria Ciobanu
- Ecologie Systématique Evolution, Centre National de la Recherche Scientifique—CNRS, Université Paris-Saclay, AgroParisTech, Orsay, France
| | - David Moreira
- Ecologie Systématique Evolution, Centre National de la Recherche Scientifique—CNRS, Université Paris-Saclay, AgroParisTech, Orsay, France
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14
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Borjas Esqueda A, Gardarin C, Laroche C. Exploring the Diversity of Red Microalgae for Exopolysaccharide Production. Mar Drugs 2022; 20:md20040246. [PMID: 35447919 PMCID: PMC9031348 DOI: 10.3390/md20040246] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2022] [Revised: 03/25/2022] [Accepted: 03/28/2022] [Indexed: 12/30/2022] Open
Abstract
Microalgae constitute a remarkable biological diversity but a limited number of them have been the object of study for their ability to produce exoplysaccharides (EPS). Among them, the red marine microalgae Porphyridium or Rhodella produce sulphated EPS, exhibiting some biological activities with potential interest in the pharmaceutical and cosmetic industries. EPS from Porphyridium and Rhodella being relatively similar in their composition, it has long been considered that all the red microalgae produced similar EPS and no attention was paid to other red microalgae. The objective of our work was then to explore the diversity of red microalgae for the production of EPS, focusing in this first step on the screening of the strains for their ability to produce EPS and preliminary structural characterization. The study was conducted with 11 microalgae strains belonging to the proteorhodophytina subphylum. All microalgae were able to produce EPS, released in the culture medium (strains belonging to Porphyridiophyceae and Rhodellophyceae classes) or remaining bound to the cells (strains from Stylonematophyceae class). The analysis of monosaccharides composition was found significantly different, with for instance high levels of glucuronic acids in the EPS from C. japonica and N. cyanea, but also strong differences in the sulphation degrees of polymers (between 1.2 and 28.7% eq. SO4).
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15
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Pánek T, Barcytė D, Treitli SC, Záhonová K, Sokol M, Ševčíková T, Zadrobílková E, Jaške K, Yubuki N, Čepička I, Eliáš M. A new lineage of non-photosynthetic green algae with extreme organellar genomes. BMC Biol 2022; 20:66. [PMID: 35296310 PMCID: PMC8928634 DOI: 10.1186/s12915-022-01263-w] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Accepted: 02/22/2022] [Indexed: 12/27/2022] Open
Abstract
Background The plastid genomes of the green algal order Chlamydomonadales tend to expand their non-coding regions, but this phenomenon is poorly understood. Here we shed new light on organellar genome evolution in Chlamydomonadales by studying a previously unknown non-photosynthetic lineage. We established cultures of two new Polytoma-like flagellates, defined their basic characteristics and phylogenetic position, and obtained complete organellar genome sequences and a transcriptome assembly for one of them. Results We discovered a novel deeply diverged chlamydomonadalean lineage that has no close photosynthetic relatives and represents an independent case of photosynthesis loss. To accommodate these organisms, we establish the new genus Leontynka, with two species (L. pallida and L. elongata) distinguishable through both their morphological and molecular characteristics. Notable features of the colourless plastid of L. pallida deduced from the plastid genome (plastome) sequence and transcriptome assembly include the retention of ATP synthase, thylakoid-associated proteins, the carotenoid biosynthesis pathway, and a plastoquinone-based electron transport chain, the latter two modules having an obvious functional link to the eyespot present in Leontynka. Most strikingly, the ~362 kbp plastome of L. pallida is by far the largest among the non-photosynthetic eukaryotes investigated to date due to an extreme proliferation of sequence repeats. These repeats are also present in coding sequences, with one repeat type found in the exons of 11 out of 34 protein-coding genes, with up to 36 copies per gene, thus affecting the encoded proteins. The mitochondrial genome of L. pallida is likewise exceptionally large, with its >104 kbp surpassed only by the mitogenome of Haematococcus lacustris among all members of Chlamydomonadales hitherto studied. It is also bloated with repeats, though entirely different from those in the L. pallida plastome, which contrasts with the situation in H. lacustris where both the organellar genomes have accumulated related repeats. Furthermore, the L. pallida mitogenome exhibits an extremely high GC content in both coding and non-coding regions and, strikingly, a high number of predicted G-quadruplexes. Conclusions With its unprecedented combination of plastid and mitochondrial genome characteristics, Leontynka pushes the frontiers of organellar genome diversity and is an interesting model for studying organellar genome evolution. Supplementary Information The online version contains supplementary material available at 10.1186/s12915-022-01263-w.
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Affiliation(s)
- Tomáš Pánek
- Department of Biology and Ecology, Faculty of Science, University of Ostrava, 701 00, Ostrava, Czech Republic.,Department of Zoology, Faculty of Science, Charles University, 128 43, Prague, Czech Republic
| | - Dovilė Barcytė
- Department of Biology and Ecology, Faculty of Science, University of Ostrava, 701 00, Ostrava, Czech Republic
| | - Sebastian C Treitli
- Department of Parasitology, Faculty of Science, Charles University, BIOCEV, 252 42, Vestec, Czech Republic
| | - Kristína Záhonová
- Department of Biology and Ecology, Faculty of Science, University of Ostrava, 701 00, Ostrava, Czech Republic
| | - Martin Sokol
- Department of Biology and Ecology, Faculty of Science, University of Ostrava, 701 00, Ostrava, Czech Republic
| | - Tereza Ševčíková
- Department of Biology and Ecology, Faculty of Science, University of Ostrava, 701 00, Ostrava, Czech Republic
| | - Eliška Zadrobílková
- Department of Zoology, Faculty of Science, Charles University, 128 43, Prague, Czech Republic
| | - Karin Jaške
- Department of Biology and Ecology, Faculty of Science, University of Ostrava, 701 00, Ostrava, Czech Republic
| | - Naoji Yubuki
- Department of Zoology, Faculty of Science, Charles University, 128 43, Prague, Czech Republic.,Bioimaging Facility, University of British Columbia, Vancouver, V6T 1Z4, Canada
| | - Ivan Čepička
- Department of Zoology, Faculty of Science, Charles University, 128 43, Prague, Czech Republic
| | - Marek Eliáš
- Department of Biology and Ecology, Faculty of Science, University of Ostrava, 701 00, Ostrava, Czech Republic.
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16
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Stephens TG, Gabr A, Calatrava V, Grossman AR, Bhattacharya D. Why is primary endosymbiosis so rare? THE NEW PHYTOLOGIST 2021; 231:1693-1699. [PMID: 34018613 PMCID: PMC8711089 DOI: 10.1111/nph.17478] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Accepted: 05/05/2021] [Indexed: 05/05/2023]
Abstract
Endosymbiosis is a relationship between two organisms wherein one cell resides inside the other. This affiliation, when stable and beneficial for the 'host' cell, can result in massive genetic innovation with the foremost examples being the evolution of eukaryotic organelles, the mitochondria and plastids. Despite its critical evolutionary role, there is limited knowledge about how endosymbiosis is initially established and how host-endosymbiont biology is integrated. Here, we explore this issue, using as our model the rhizarian amoeba Paulinella, which represents an independent case of primary plastid origin that occurred c. 120 million yr ago. We propose the 'chassis and engine' model that provides a theoretical framework for understanding primary plastid endosymbiosis, potentially explaining why it is so rare.
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Affiliation(s)
- Timothy G. Stephens
- Department of Biochemistry and Microbiology, Rutgers University, New Brunswick, NJ 08901, USA
| | - Arwa Gabr
- Graduate Program in Molecular Bioscience and Program in Microbiology and Molecular Genetics, Rutgers University, Piscataway, NJ 08854, USA
| | - Victoria Calatrava
- Department of Plant Biology, The Carnegie Institution, Stanford, CA 94305, USA
| | - Arthur R. Grossman
- Department of Plant Biology, The Carnegie Institution, Stanford, CA 94305, USA
| | - Debashish Bhattacharya
- Department of Biochemistry and Microbiology, Rutgers University, New Brunswick, NJ 08901, USA
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Barcytė D, Eikrem W, Engesmo A, Seoane S, Wohlmann J, Horák A, Yurchenko T, Eliáš M. Olisthodiscus represents a new class of Ochrophyta. JOURNAL OF PHYCOLOGY 2021; 57:1094-1118. [PMID: 33655496 DOI: 10.1111/jpy.13155] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Revised: 12/08/2020] [Accepted: 01/04/2021] [Indexed: 06/12/2023]
Abstract
The phylogenetic diversity of Ochrophyta, a diverse and ecologically important radiation of algae, is still incompletely understood even at the level of the principal lineages. One taxon that has eluded simple classification is the marine flagellate genus Olisthodiscus. We investigated Olisthodiscus luteus K-0444 and documented its morphological and genetic differences from the NIES-15 strain, which we described as Olisthodiscus tomasii sp. nov. Phylogenetic analyses of combined 18S and 28S rRNA sequences confirmed that Olisthodiscus constitutes a separate, deep, ochrophyte lineage, but its position could not be resolved. To overcome this problem, we sequenced the plastid genome of O. luteus K-0444 and used the new data in multigene phylogenetic analyses, which suggested that Olisthodiscus is a sister lineage of the class Pinguiophyceae within a broader clade additionally including Chrysophyceae, Synchromophyceae, and Eustigmatophyceae. Surprisingly, the Olisthodiscus plastid genome contained three genes, ycf80, cysT, and cysW, inherited from the rhodophyte ancestor of the ochrophyte plastid yet lost from all other ochrophyte groups studied so far. Combined with nuclear genes for CysA and Sbp proteins, Olisthodiscus is the only known ochrophyte possessing a plastidial sulfate transporter SulT. In addition, the finding of a cemA gene in the Olisthodiscus plastid genome and an updated phylogenetic analysis ruled out the previously proposed hypothesis invoking horizontal cemA transfer from a green algal plastid into Synurales. Altogether, Olisthodiscus clearly represents a novel phylogenetically distinct ochrophyte lineage, which we have proposed as a new class, Olisthodiscophyceae.
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Affiliation(s)
- Dovilė Barcytė
- Department of Biology and Ecology, Faculty of Science, University of Ostrava, 710 00, Ostrava, Czech Republic
| | - Wenche Eikrem
- Norwegian Institute for Water Research, Gaustadallèen 21, 0349, Oslo, Norway
- Natural history Museum, University of Oslo, P.O. Box 1172 Blindern, 0318, Oslo, Norway
- Department of Biosciences, University of Oslo, P.O. Box 1066 Blindern, 0316, Oslo, Norway
| | - Anette Engesmo
- Norwegian Institute for Water Research, Gaustadallèen 21, 0349, Oslo, Norway
- Department of Biosciences, University of Oslo, P.O. Box 1066 Blindern, 0316, Oslo, Norway
| | - Sergio Seoane
- Department of Plant Biology and Ecology, University of the Basque Country (UPV/EHU), 48940, Leioa, Spain
| | - Jens Wohlmann
- Department of Biosciences, University of Oslo, P.O. Box 1066 Blindern, 0316, Oslo, Norway
| | - Aleš Horák
- Biology Centre, Czech Academy of Sciences, Institute of Parasitology, Branišovská 31, 37005, České Budějovice, Czech Republic
- Department of Molecular Biology, Faculty of Science, University of South Bohemia, Branišovská 31, 37005, České Budějovice, Czech Republic
| | - Tatiana Yurchenko
- Department of Biology and Ecology, Faculty of Science, University of Ostrava, 710 00, Ostrava, Czech Republic
| | - Marek Eliáš
- Department of Biology and Ecology, Faculty of Science, University of Ostrava, 710 00, Ostrava, Czech Republic
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Abstract
The origin of plastids (chloroplasts) by endosymbiosis stands as one of the most important events in the history of eukaryotic life. The genetic, biochemical, and cell biological integration of a cyanobacterial endosymbiont into a heterotrophic host eukaryote approximately a billion years ago paved the way for the evolution of diverse algal groups in a wide range of aquatic and, eventually, terrestrial environments. Plastids have on multiple occasions also moved horizontally from eukaryote to eukaryote by secondary and tertiary endosymbiotic events. The overall picture of extant photosynthetic diversity can best be described as “patchy”: Plastid-bearing lineages are spread far and wide across the eukaryotic tree of life, nested within heterotrophic groups. The algae do not constitute a monophyletic entity, and understanding how, and how often, plastids have moved from branch to branch on the eukaryotic tree remains one of the most fundamental unsolved problems in the field of cell evolution. In this review, we provide an overview of recent advances in our understanding of the origin and spread of plastids from the perspective of comparative genomics. Recent years have seen significant improvements in genomic sampling from photosynthetic and nonphotosynthetic lineages, both of which have added important pieces to the puzzle of plastid evolution. Comparative genomics has also allowed us to better understand how endosymbionts become organelles.
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Affiliation(s)
- Shannon J Sibbald
- Department of Biochemistry & Molecular Biology, Dalhousie University, Halifax, Nova Scotia, Canada.,Centre for Comparative Genomics and Evolutionary Bioinformatics, Dalhousie University, Halifax, Nova Scotia, Canada
| | - John M Archibald
- Department of Biochemistry & Molecular Biology, Dalhousie University, Halifax, Nova Scotia, Canada.,Centre for Comparative Genomics and Evolutionary Bioinformatics, Dalhousie University, Halifax, Nova Scotia, Canada
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Petroll R, Schreiber M, Finke H, Cock JM, Gould SB, Rensing SA. Signatures of Transcription Factor Evolution and the Secondary Gain of Red Algae Complexity. Genes (Basel) 2021; 12:1055. [PMID: 34356071 PMCID: PMC8304369 DOI: 10.3390/genes12071055] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Revised: 07/04/2021] [Accepted: 07/05/2021] [Indexed: 01/01/2023] Open
Abstract
Red algae (Rhodophyta) belong to the superphylum Archaeplastida, and are a species-rich group exhibiting diverse morphologies. Theory has it that the unicellular red algal ancestor went through a phase of genome contraction caused by adaptation to extreme environments. More recently, the classes Porphyridiophyceae, Bangiophyceae, and Florideophyceae experienced genome expansions, coinciding with an increase in morphological complexity. Transcription-associated proteins (TAPs) regulate transcription, show lineage-specific patterns, and are related to organismal complexity. To better understand red algal TAP complexity and evolution, we investigated the TAP family complement of uni- and multi-cellular red algae. We found that the TAP family complement correlates with gain of morphological complexity in the multicellular Bangiophyceae and Florideophyceae, and that abundance of the C2H2 zinc finger transcription factor family may be associated with the acquisition of morphological complexity. An expansion of heat shock transcription factors (HSF) occurred within the unicellular Cyanidiales, potentially as an adaption to extreme environmental conditions.
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Affiliation(s)
- Romy Petroll
- Plant Cell Biology, Department of Biology, University of Marburg, 35037 Marburg, Germany; (R.P.); (M.S.); (H.F.); (S.B.G.)
| | - Mona Schreiber
- Plant Cell Biology, Department of Biology, University of Marburg, 35037 Marburg, Germany; (R.P.); (M.S.); (H.F.); (S.B.G.)
- Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), 06466 Gatersleben, Germany
| | - Hermann Finke
- Plant Cell Biology, Department of Biology, University of Marburg, 35037 Marburg, Germany; (R.P.); (M.S.); (H.F.); (S.B.G.)
| | - J. Mark Cock
- Algal Genetics Group, UMR 8227, Integrative Biology of Marine Models, Station Biologique de Roscoff, Sorbonne Université, CNRS, UPMC University Paris 06, CS 90074, 29688 Roscoff, France;
| | - Sven B. Gould
- Plant Cell Biology, Department of Biology, University of Marburg, 35037 Marburg, Germany; (R.P.); (M.S.); (H.F.); (S.B.G.)
- Institute for Molecular Evolution, Heinrich-Heine-University Düsseldorf, 40225 Düsseldorf, Germany
| | - Stefan A. Rensing
- Plant Cell Biology, Department of Biology, University of Marburg, 35037 Marburg, Germany; (R.P.); (M.S.); (H.F.); (S.B.G.)
- Centre for Biological Signaling Studies (BIOSS), University of Freiburg, 79108 Freiburg, Germany
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20
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Gastineau R, Davidovich NA, Davidovich OI, Lemieux C, Turmel M, Wróbel RJ, Witkowski A. Extreme Enlargement of the Inverted Repeat Region in the Plastid Genomes of Diatoms from the Genus Climaconeis. Int J Mol Sci 2021; 22:7155. [PMID: 34281209 PMCID: PMC8268801 DOI: 10.3390/ijms22137155] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Revised: 06/29/2021] [Accepted: 06/30/2021] [Indexed: 11/17/2022] Open
Abstract
We sequenced the plastid genomes of three diatoms from the genus Climaconeis, including two strains formerly designated as Climaconeis scalaris. At 208,097 and 216,580 bp, the plastid genomes of the latter strains are the largest ever sequenced among diatoms and their increased size is explained by the massive expansion of the inverted repeat region. Important rearrangements of gene order were identified among the two populations of Climaconeis cf. scalaris. The other sequenced Climaconeis chloroplast genome is 1.5 times smaller compared with those of the Climaconeis cf. scalaris strains and it features an usual quadripartite structure. The extensive structural changes reported here for the genus Climaconeis are compared with those previously observed for other algae and plants displaying large plastid genomes.
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Affiliation(s)
- Romain Gastineau
- Institute of Marine and Environmental Sciences, University of Szczecin, Mickiewicza 16a, 70-383 Szczecin, Poland; (N.A.D.); (A.W.)
| | - Nikolaï A. Davidovich
- Institute of Marine and Environmental Sciences, University of Szczecin, Mickiewicza 16a, 70-383 Szczecin, Poland; (N.A.D.); (A.W.)
- Karadag Scientific Station–Natural Reserve of the Russian Academy of Sciences, p/o Kurortnoe, Feodosiya, 98188 Crimea, Russia;
| | - Olga I. Davidovich
- Karadag Scientific Station–Natural Reserve of the Russian Academy of Sciences, p/o Kurortnoe, Feodosiya, 98188 Crimea, Russia;
| | - Claude Lemieux
- Département de Biochimie, de Microbiologie et de Bio-Informatique, Institut de Biologie Intégrative et des Systèmes, Université Laval, Québec, QC G1V 0A6, Canada; (C.L.); (M.T.)
| | - Monique Turmel
- Département de Biochimie, de Microbiologie et de Bio-Informatique, Institut de Biologie Intégrative et des Systèmes, Université Laval, Québec, QC G1V 0A6, Canada; (C.L.); (M.T.)
| | - Rafał J. Wróbel
- Engineering of Catalytic and Sorbent Materials Department, Faculty of Chemical Technology and Engineering, West Pomeranian University of Technology Szczecin, Pułaskiego 10, 70-322 Szczecin, Poland;
| | - Andrzej Witkowski
- Institute of Marine and Environmental Sciences, University of Szczecin, Mickiewicza 16a, 70-383 Szczecin, Poland; (N.A.D.); (A.W.)
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21
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Preuss M, Verbruggen H, West JA, Zuccarello GC. Divergence times and plastid phylogenomics within the intron-rich order Erythropeltales (Compsopogonophyceae, Rhodophyta). JOURNAL OF PHYCOLOGY 2021; 57:1035-1044. [PMID: 33657649 DOI: 10.1111/jpy.13159] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2020] [Revised: 01/25/2021] [Accepted: 02/04/2021] [Indexed: 06/12/2023]
Abstract
The advent of high-throughput sequencing (HTS) has allowed for the use of large numbers of coding regions to produce robust phylogenies. These phylogenies have been used to highlight relationships at ancient diversifications (subphyla, class) and highlight the evolution of plastid genome structure. The Erythropeltales are an order in the Compsopogonophyceae, a group with unusual plastid genomes but with low taxon sampling. We use HTS to produce near complete plastid genomes of all genera, and multiple species within some genera, to produce robust phylogenies to investigate character evolution, dating of divergence in the group, and plastid organization, including intron patterns. Our results produce a fully supported phylogeny of the genera in the Erythropeltales and suggest that morphologies (upright versus crustose) have evolved multiple times. Our dated phylogeny also indicates that the order is very old (~800 Ma), with diversification occurring after the ice ages of the Cryogenian period (750-635 Ma). Plastid gene order is congruent with phylogenetic relationships and suggests that genome architecture does not change often. Our data also highlight the abundance of introns in the plastid genomes of this order. We also produce a nearly complete plastid genome of Tsunamia transpacifica (Stylonematophyceae) to add to the taxon sampling of genomes of this class. The use of plastid genomes clearly produces robust phylogenetic relationships that can be used to infer evolutionary events, and increased taxon sampling, especially in less well-known red algal groups, will provide additional insights into their evolution.
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Affiliation(s)
- Maren Preuss
- School of Biological Sciences, Victoria University of Wellington, PO Box 600, Wellington, 6140, New Zealand
| | - Heroen Verbruggen
- School of BioSciences, University of Melbourne, Parkville, Victoria, 3010, Australia
| | - John A West
- School of BioSciences, University of Melbourne, Parkville, Victoria, 3010, Australia
| | - Giuseppe C Zuccarello
- School of Biological Sciences, Victoria University of Wellington, PO Box 600, Wellington, 6140, New Zealand
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22
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Ren Q, Wang YC, Lin Y, Zhen Z, Cui Y, Qin S. The extremely large chloroplast genome of the green alga Haematococcus pluvialis: Genome structure, and comparative analysis. ALGAL RES 2021. [DOI: 10.1016/j.algal.2021.102308] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Goodson HV, Kelley JB, Brawley SH. Cytoskeletal diversification across 1 billion years: What red algae can teach us about the cytoskeleton, and vice versa. Bioessays 2021; 43:e2000278. [PMID: 33797088 DOI: 10.1002/bies.202000278] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2020] [Revised: 01/22/2021] [Accepted: 01/28/2021] [Indexed: 11/05/2022]
Abstract
The cytoskeleton has a central role in eukaryotic biology, enabling cells to organize internally, polarize, and translocate. Studying cytoskeletal machinery across the tree of life can identify common elements, illuminate fundamental mechanisms, and provide insight into processes specific to less-characterized organisms. Red algae represent an ancient lineage that is diverse, ecologically significant, and biomedically relevant. Recent genomic analysis shows that red algae have a surprising paucity of cytoskeletal elements, particularly molecular motors. Here, we review the genomic and cell biological evidence and propose testable models of how red algal cells might perform processes including cell motility, cytokinesis, intracellular transport, and secretion, given their reduced cytoskeletons. In addition to enhancing understanding of red algae and lineages that evolved from red algal endosymbioses (e.g., apicomplexan parasites), these ideas may also provide insight into cytoskeletal processes in animal cells.
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Affiliation(s)
- Holly V Goodson
- Department of Chemistry and Biochemistry and Department of Biological Sciences, University of Notre Dame, Notre Dame, Indiana, USA
| | - Joshua B Kelley
- Department of Molecular and Biomedical Sciences, University of Maine, Orono, Maine, USA
| | - Susan H Brawley
- School of Marine Sciences, University of Maine, Orono, Maine, USA
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Rappemonads are haptophyte phytoplankton. Curr Biol 2021; 31:2395-2403.e4. [PMID: 33773100 DOI: 10.1016/j.cub.2021.03.012] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2021] [Revised: 02/12/2021] [Accepted: 03/03/2021] [Indexed: 11/20/2022]
Abstract
Rapidly accumulating genetic data from environmental sequencing approaches have revealed an extraordinary level of unsuspected diversity within marine phytoplankton,1-11 which is responsible for around 50% of global net primary production.12,13 However, the phenotypic identity of many of the organisms distinguished by environmental DNA sequences remains unclear. The rappemonads represent a plastid-bearing protistan lineage that to date has only been identified by environmental plastid 16S rRNA sequences.14-17 The phenotypic identity of this group, which does not confidently cluster in any known algal clades in 16S rRNA phylogenetic reconstructions,15 has remained unknown since the first report of environmental sequences over two decades ago. We show that rappemonads are closely related to a haptophyte microalga, Pavlomulina ranunculiformis gen. nov. et sp. nov., and belong to a new haptophyte class, the Rappephyceae. Organellar phylogenomic analyses provide strong evidence for the inclusion of this lineage within the Haptophyta as a sister group to the Prymnesiophyceae. Members of this new class have a cosmopolitan distribution in coastal and oceanic regions. The relative read abundance of Rappephyceae in a large environmental barcoding dataset was comparable to, or greater than, those of major haptophyte species, such as the bloom-forming Gephyrocapsa huxleyi and Prymnesium parvum, and this result indicates that they likely have a significant impact as primary producers. Detailed characterization of Pavlomulina allowed for reconstruction of the ancient evolutionary history of the Haptophyta, a group that is one of the most important components of extant marine phytoplankton communities.
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Strassert JFH, Irisarri I, Williams TA, Burki F. A molecular timescale for eukaryote evolution with implications for the origin of red algal-derived plastids. Nat Commun 2021; 12:1879. [PMID: 33767194 PMCID: PMC7994803 DOI: 10.1038/s41467-021-22044-z] [Citation(s) in RCA: 88] [Impact Index Per Article: 29.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2020] [Accepted: 02/25/2021] [Indexed: 01/31/2023] Open
Abstract
In modern oceans, eukaryotic phytoplankton is dominated by lineages with red algal-derived plastids such as diatoms, dinoflagellates, and coccolithophores. Despite the ecological importance of these groups and many others representing a huge diversity of forms and lifestyles, we still lack a comprehensive understanding of their evolution and how they obtained their plastids. New hypotheses have emerged to explain the acquisition of red algal-derived plastids by serial endosymbiosis, but the chronology of these putative independent plastid acquisitions remains untested. Here, we establish a timeframe for the origin of red algal-derived plastids under scenarios of serial endosymbiosis, using Bayesian molecular clock analyses applied on a phylogenomic dataset with broad sampling of eukaryote diversity. We find that the hypotheses of serial endosymbiosis are chronologically possible, as the stem lineages of all red plastid-containing groups overlap in time. This period in the Meso- and Neoproterozoic Eras set the stage for the later expansion to dominance of red algal-derived primary production in the contemporary oceans, which profoundly altered the global geochemical and ecological conditions of the Earth.
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Affiliation(s)
- Jürgen F H Strassert
- Department of Organismal Biology, Program in Systematic Biology, Uppsala University, Uppsala, Sweden
- Department of Ecosystem Research, Leibniz Institute of Freshwater Ecology and Inland Fisheries, Berlin, Germany
| | - Iker Irisarri
- Department of Organismal Biology, Program in Systematic Biology, Uppsala University, Uppsala, Sweden
- Department of Biodiversity and Evolutionary Biology, Museo Nacional de Ciencias Naturales (MNCN-CSIC), Madrid, Spain
- Department of Applied Bioinformatics, Institute for Microbiology and Genetics, University of Göttingen, and Campus Institute Data Science (CIDAS), Göttingen, Germany
| | - Tom A Williams
- School of Biological Sciences, University of Bristol, Life Sciences Building, Bristol, UK
| | - Fabien Burki
- Department of Organismal Biology, Program in Systematic Biology, Uppsala University, Uppsala, Sweden.
- Science for Life Laboratory, Uppsala University, Uppsala, Sweden.
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Muñoz-Gómez SA, Bilolikar G, Wideman JG, Geiler-Samerotte K. Constructive Neutral Evolution 20 Years Later. J Mol Evol 2021; 89:172-182. [PMID: 33604782 PMCID: PMC7982386 DOI: 10.1007/s00239-021-09996-y] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2020] [Accepted: 01/13/2021] [Indexed: 12/29/2022]
Abstract
Evolution has led to a great diversity that ranges from elegant simplicity to ornate complexity. Many complex features are often assumed to be more functional or adaptive than their simpler alternatives. However, in 1999, Arlin Stolzfus published a paper in the Journal of Molecular Evolution that outlined a framework in which complexity can arise through a series of non-adaptive steps. He called this framework Constructive Neutral Evolution (CNE). Despite its two-decade-old roots, many evolutionary biologists still appear to be unaware of this explanatory framework for the origins of complexity. In this perspective piece, we explain the theory of CNE and how it changes the order of events in narratives that describe the evolution of complexity. We also provide an extensive list of cellular features that may have become more complex through CNE. We end by discussing strategies to determine whether complexity arose through neutral or adaptive processes.
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Affiliation(s)
- Sergio A Muñoz-Gómez
- School of Life Sciences, Biodesign Center for Mechanisms of Evolution, Arizona State University, Tempe, AZ, USA.
| | - Gaurav Bilolikar
- School of Life Sciences, Biodesign Center for Mechanisms of Evolution, Arizona State University, Tempe, AZ, USA
| | - Jeremy G Wideman
- School of Life Sciences, Biodesign Center for Mechanisms of Evolution, Arizona State University, Tempe, AZ, USA
| | - Kerry Geiler-Samerotte
- School of Life Sciences, Biodesign Center for Mechanisms of Evolution, Arizona State University, Tempe, AZ, USA.
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Guo YY, Yang JX, Li HK, Zhao HS. Chloroplast Genomes of Two Species of Cypripedium: Expanded Genome Size and Proliferation of AT-Biased Repeat Sequences. FRONTIERS IN PLANT SCIENCE 2021; 12:609729. [PMID: 33633763 PMCID: PMC7900419 DOI: 10.3389/fpls.2021.609729] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2020] [Accepted: 01/20/2021] [Indexed: 05/07/2023]
Abstract
The size of the chloroplast genome (plastome) of autotrophic angiosperms is generally conserved. However, the chloroplast genomes of some lineages are greatly expanded, which may render assembling these genomes from short read sequencing data more challenging. Here, we present the sequencing, assembly, and annotation of the chloroplast genomes of Cypripedium tibeticum and Cypripedium subtropicum. We de novo assembled the chloroplast genomes of the two species with a combination of short-read Illumina data and long-read PacBio data. The plastomes of the two species are characterized by expanded genome size, proliferated AT-rich repeat sequences, low GC content and gene density, as well as low substitution rates of the coding genes. The plastomes of C. tibeticum (197,815 bp) and C. subtropicum (212,668 bp) are substantially larger than those of the three species sequenced in previous studies. The plastome of C. subtropicum is the longest one of Orchidaceae to date. Despite the increase in genome size, the gene order and gene number of the plastomes are conserved, with the exception of an ∼75 kb large inversion in the large single copy (LSC) region shared by the two species. The most striking is the record-setting low GC content in C. subtropicum (28.2%). Moreover, the plastome expansion of the two species is strongly correlated with the proliferation of AT-biased non-coding regions: the non-coding content of C. subtropicum is in excess of 57%. The genus provides a typical example of plastome expansion induced by the expansion of non-coding regions. Considering the pros and cons of different sequencing technologies, we recommend hybrid assembly based on long and short reads applied to the sequencing of plastomes with AT-biased base composition.
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Ocaña-Pallarès E, Vergara Z, Desvoyes B, Tejada-Jimenez M, Romero-Jurado A, Galván A, Fernández E, Ruiz-Trillo I, Gutierrez C. Origin Recognition Complex (ORC) Evolution Is Influenced by Global Gene Duplication/Loss Patterns in Eukaryotic Genomes. Genome Biol Evol 2020; 12:3878-3889. [PMID: 31990293 PMCID: PMC7058166 DOI: 10.1093/gbe/evaa011] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/14/2020] [Indexed: 12/29/2022] Open
Abstract
The conservation of orthologs of most subunits of the origin recognition complex (ORC) has served to propose that the whole complex is common to all eukaryotes. However, various uncertainties have arisen concerning ORC subunit composition in a variety of lineages. Also, it is unclear whether the ancestral diversification of ORC in eukaryotes was accompanied by the neofunctionalization of some subunits, for example, role of ORC1 in centriole homeostasis. We have addressed these questions by reconstructing the distribution and evolutionary history of ORC1-5/CDC6 in a taxon-rich eukaryotic data set. First, we identified ORC subunits previously undetected in divergent lineages, which allowed us to propose a series of parsimonious scenarios for the origin of this multiprotein complex. Contrary to previous expectations, we found a global tendency in eukaryotes to increase or decrease the number of subunits as a consequence of genome duplications or streamlining, respectively. Interestingly, parasites show significantly lower number of subunits than free-living eukaryotes, especially those with the lowest genome size and gene content metrics. We also investigated the evolutionary origin of the ORC1 role in centriole homeostasis mediated by the PACT region in human cells. In particular, we tested the consequences of reducing ORC1 levels in the centriole-containing green alga Chlamydomonas reinhardtii. We found that the proportion of centrioles to flagella and nuclei was not dramatically affected. This, together with the PACT region not being significantly more conserved in centriole-bearing eukaryotes, supports the notion that this neofunctionalization of ORC1 would be a recent acquisition rather than an ancestral eukaryotic feature.
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Affiliation(s)
| | - Zaida Vergara
- Centro de Biologia Molecular Severo Ochoa, CSIC-UAM, Cantoblanco, Madrid, Spain
| | - Bénédicte Desvoyes
- Centro de Biologia Molecular Severo Ochoa, CSIC-UAM, Cantoblanco, Madrid, Spain
| | - Manuel Tejada-Jimenez
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias, Universidad de Córdoba, Córdoba, Spain
| | - Ainoa Romero-Jurado
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias, Universidad de Córdoba, Córdoba, Spain
| | - Aurora Galván
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias, Universidad de Córdoba, Córdoba, Spain
| | - Emilio Fernández
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias, Universidad de Córdoba, Córdoba, Spain
| | - Iñaki Ruiz-Trillo
- Institut de Biologia Evolutiva (CSIC-Universitat Pompeu Fabra), Barcelona, Spain.,Departament de Genètica, Microbiologia i Estadística, Universitat de Barcelona, Barcelona, Spain.,ICREA, Barcelona, Spain
| | - Crisanto Gutierrez
- Centro de Biologia Molecular Severo Ochoa, CSIC-UAM, Cantoblanco, Madrid, Spain
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29
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Fang J, Lin A, Yuan X, Chen Y, He W, Huang J, Zhang X, Lin G, Zhang J, Xue T. The complete chloroplast genome of Isochrysis galbana and comparison with related haptophyte species. ALGAL RES 2020. [DOI: 10.1016/j.algal.2020.101989] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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30
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Evans JR, Vis ML. Relative expression analysis of light-harvesting genes in the freshwater alga Lympha mucosa (Batrachospermales, Rhodophyta). JOURNAL OF PHYCOLOGY 2020; 56:540-548. [PMID: 31930498 PMCID: PMC9290634 DOI: 10.1111/jpy.12967] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/28/2018] [Accepted: 12/16/2019] [Indexed: 06/10/2023]
Abstract
Members of the freshwater red algal order Batrachospermales are often described as shade-adapted. Nevertheless, recent ecophysiological studies have demonstrated species-level differences in acclimation to a range of irradiances. Lympha mucosa occurs in open and shaded portions of temperate streams and is abundant during summer months, suggesting it tolerates high and low irradiances. Specimens of L. mucosa were collected from open (sun-acclimated) or shaded (shade-acclimated) sites and exposed to low (<20 μmol photons · m-2 · s-1 ) or high (220 μmol photon · m-2 · s-1 ) light for 72 h to examine mechanisms of photoacclimation at the transcriptional level. High-throughput sequence data were used to design specific primers for genes involved with light harvesting and these were quantified with qPCR. The greatest significant difference in transcript abundances was observed in the psaA gene (Photosystem I P700 apoprotein), and site-type had an effect on these responses. Shade-acclimated thalli were 22-fold down-regulated at high light, whereas sun-acclimated thalli were only 5-fold down-regulated. Another gene involved with Photosystem I (petF ferredoxin) was down-regulated at high light, but only individuals from the shaded site were significantly different (4-fold). In thalli from both sites, cpeA (Phycoerythrin alpha chain) was down-regulated at high light. Although not statistically significant, patterns consistent with previous physiological and transcriptomic studies were uncovered, namely the inverse response of transcriptional activity in genes that encode phycobiliproteins. In support of previous ecophysiological studies of freshwater red algae, these data indicate significant transcriptional changes involving Photosystem I and phycobiliprotein synthesis are required to tolerate and grow at various irradiances.
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Affiliation(s)
- Joshua R. Evans
- Department of Environmental and Plant BiologyOhio UniversityAthensOhio45701USA
| | - Morgan L. Vis
- Department of Environmental and Plant BiologyOhio UniversityAthensOhio45701USA
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31
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Dinoflagellates with relic endosymbiont nuclei as models for elucidating organellogenesis. Proc Natl Acad Sci U S A 2020; 117:5364-5375. [PMID: 32094181 DOI: 10.1073/pnas.1911884117] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Nucleomorphs are relic endosymbiont nuclei so far found only in two algal groups, cryptophytes and chlorarachniophytes, which have been studied to model the evolutionary process of integrating an endosymbiont alga into a host-governed plastid (organellogenesis). However, past studies suggest that DNA transfer from the endosymbiont to host nuclei had already ceased in both cryptophytes and chlorarachniophytes, implying that the organellogenesis at the genetic level has been completed in the two systems. Moreover, we have yet to pinpoint the closest free-living relative of the endosymbiotic alga engulfed by the ancestral chlorarachniophyte or cryptophyte, making it difficult to infer how organellogenesis altered the endosymbiont genome. To counter the above issues, we need novel nucleomorph-bearing algae, in which endosymbiont-to-host DNA transfer is on-going and for which endosymbiont/plastid origins can be inferred at a fine taxonomic scale. Here, we report two previously undescribed dinoflagellates, strains MGD and TGD, with green algal endosymbionts enclosing plastids as well as relic nuclei (nucleomorphs). We provide evidence for the presence of DNA in the two nucleomorphs and the transfer of endosymbiont genes to the host (dinoflagellate) genomes. Furthermore, DNA transfer between the host and endosymbiont nuclei was found to be in progress in both the MGD and TGD systems. Phylogenetic analyses successfully resolved the origins of the endosymbionts at the genus level. With the combined evidence, we conclude that the host-endosymbiont integration in MGD/TGD is less advanced than that in cryptophytes/chrorarachniophytes, and propose the two dinoflagellates as models for elucidating organellogenesis.
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32
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Ponce-Toledo RI, Moreira D, López-García P, Deschamps P. Secondary Plastids of Euglenids and Chlorarachniophytes Function with a Mix of Genes of Red and Green Algal Ancestry. Mol Biol Evol 2020; 35:2198-2204. [PMID: 29924337 DOI: 10.1093/molbev/msy121] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Endosymbiosis has been common all along eukaryotic evolution, providing opportunities for genomic and organellar innovation. Plastids are a prominent example. After the primary endosymbiosis of the cyanobacterial plastid ancestor, photosynthesis spread in many eukaryotic lineages via secondary endosymbioses involving red or green algal endosymbionts and diverse heterotrophic hosts. However, the number of secondary endosymbioses and how they occurred remain poorly understood. In particular, contrasting patterns of endosymbiotic gene transfer have been detected and subjected to various interpretations. In this context, accurate detection of endosymbiotic gene transfers is essential to avoid wrong evolutionary conclusions. We have assembled a strictly selected set of markers that provides robust phylogenomic evidence suggesting that nuclear genes involved in the function and maintenance of green secondary plastids in chlorarachniophytes and euglenids have unexpected mixed red and green algal origins. This mixed ancestry contrasts with the clear red algal origin of most nuclear genes carrying similar functions in secondary algae with red plastids.
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Affiliation(s)
- Rafael I Ponce-Toledo
- Unité d'Ecologie Systématique et Evolution, CNRS, Université Paris-Sud, AgroParisTech, Université Paris-Saclay, Orsay, France
| | - David Moreira
- Unité d'Ecologie Systématique et Evolution, CNRS, Université Paris-Sud, AgroParisTech, Université Paris-Saclay, Orsay, France
| | - Purificación López-García
- Unité d'Ecologie Systématique et Evolution, CNRS, Université Paris-Sud, AgroParisTech, Université Paris-Saclay, Orsay, France
| | - Philippe Deschamps
- Unité d'Ecologie Systématique et Evolution, CNRS, Université Paris-Sud, AgroParisTech, Université Paris-Saclay, Orsay, France
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33
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Martínez-Alberola F, Barreno E, Casano LM, Gasulla F, Molins A, Moya P, González-Hourcade M, Del Campo EM. The chloroplast genome of the lichen-symbiont microalga Trebouxia sp. Tr9 (Trebouxiophyceae, Chlorophyta) shows short inverted repeats with a single gene and loss of the rps4 gene, which is encoded by the nucleus. JOURNAL OF PHYCOLOGY 2020; 56:170-184. [PMID: 31578712 DOI: 10.1111/jpy.12928] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2019] [Accepted: 09/15/2019] [Indexed: 06/10/2023]
Abstract
The Trebouxiophyceae is the class of Chlorophyta algae from which the highest number of chloroplast genome (cpDNA) sequences has been obtained. Several species in this class participate in symbioses with fungi to form lichens. However, no cpDNA has been obtained from any Trebouxia lichen-symbiont microalgae, which are present in approximately half of all lichens. Here, we report the sequence of the completely assembled cpDNA from Trebouxia sp. TR9 and a comparative study with other Trebouxio-phyceae. The organization of the chloroplast genome of Trebouxia sp. TR9 has certain features that are unusual in the Trebouxiophyceae and other green algae. The most remarkable characteristics are the presence of long intergenic spacers, a quadripartite structure with short inverted repeated sequences (IRs), and the loss of the rps4 gene. The presence of long intergenic spacers accounts for a larger cpDNA size in comparison to other closely related Trebouxiophyceae. The IRs, which were thought to be lost in the Trebouxiales, are distinct from most of cpDNAs since they lack the rRNA operon and uniquely includes the rbcL gene. The functional transfer of the rps4 gene to the nuclear genome has been confirmed by sequencing and examination of the gene architecture, which includes three spliceosomal introns as well as the verification of the presence of the corresponding transcript. This is the first documented transfer of the rps4 gene from the chloroplast to the nucleus among Viridiplantae. Additionally, a fairly well-resolved phylogenetic reconstruction, including Trebouxia sp. TR9 along with other Trebouxiophyceae, was obtained based on a set of conserved chloroplast genes.
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Affiliation(s)
- Fernando Martínez-Alberola
- ICBIBE, Botánica, Facultad de Ciencias Biológicas, Universitat de València, Dr. Moliner 50, Burjassot, Valencia, 46100, Spain
| | - Eva Barreno
- ICBIBE, Botánica, Facultad de Ciencias Biológicas, Universitat de València, Dr. Moliner 50, Burjassot, Valencia, 46100, Spain
| | - Leonardo M Casano
- Department of Life Sciences, University of Alcalá, Alcalá de Henares, Madrid, 28805, Spain
| | - Francisco Gasulla
- Department of Life Sciences, University of Alcalá, Alcalá de Henares, Madrid, 28805, Spain
| | - Arantzazu Molins
- ICBIBE, Botánica, Facultad de Ciencias Biológicas, Universitat de València, Dr. Moliner 50, Burjassot, Valencia, 46100, Spain
| | - Patricia Moya
- ICBIBE, Botánica, Facultad de Ciencias Biológicas, Universitat de València, Dr. Moliner 50, Burjassot, Valencia, 46100, Spain
| | | | - Eva M Del Campo
- Department of Life Sciences, University of Alcalá, Alcalá de Henares, Madrid, 28805, Spain
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Substrate specificity of plastid phosphate transporters in a non-photosynthetic diatom and its implication in evolution of red alga-derived complex plastids. Sci Rep 2020; 10:1167. [PMID: 31980711 PMCID: PMC6981301 DOI: 10.1038/s41598-020-58082-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2019] [Accepted: 01/07/2020] [Indexed: 02/07/2023] Open
Abstract
The triose phosphate transporter (TPT) is one of the prerequisites to exchange metabolites between the cytosol and plastids. In this study, we demonstrated that the four plastid TPT homologues in the non-photosynthetic diatom Nitzschia sp. NIES-3581 were highly likely integrated into plastid envelope membranes similar to counterparts in the model photosynthetic diatom Phaeodactylum tricornutum, in terms of target membranes and C-terminal orientations. Three of the four Nitzschia TPT homologues are capable of transporting various metabolites into proteo-liposomes including triose phosphates (TPs) and phosphoenolpyruvate (PEP), the transport substrates sufficient to support the metabolic pathways retained in the non-photosynthetic diatom plastid. Phylogenetic analysis of TPTs and closely related transporter proteins indicated that diatoms and other algae with red alga-derived complex plastids possess only TPT homologues but lack homologues of the glucose 6-phosphate transporter (GPT), xylulose 5-phosphate transporter (XPT), and phosphoenolpyruvate transporter (PPT). Comparative sequence analysis suggests that many TPT homologues of red alga-derived complex plastids potentially have the ability to transport mainly TPs and PEP. TPTs transporting both TPs and PEP highly likely mediate a metabolic crosstalk between a red alga-derived complex plastid and the cytosol in photosynthetic and non-photosynthetic species, which explains the lack of PPTs in all the lineages with red alga-derived complex plastids. The PEP-transporting TPTs might have emerged in an early phase of endosymbiosis between a red alga and a eukaryote host, given the broad distribution of that type of transporters in all branches of red alga-derived complex plastid-bearing lineages, and have probably played a key role in the establishment and retention of a controllable, intracellular metabolic connection in those organisms.
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35
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Lee J, Kim D, Bhattacharya D, Yoon HS. Expansion of phycobilisome linker gene families in mesophilic red algae. Nat Commun 2019; 10:4823. [PMID: 31645564 PMCID: PMC6811547 DOI: 10.1038/s41467-019-12779-1] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2019] [Accepted: 09/26/2019] [Indexed: 02/02/2023] Open
Abstract
The common ancestor of red algae (Rhodophyta) has undergone massive genome reduction, whereby 25% of the gene inventory has been lost, followed by its split into the species-poor extremophilic Cyanidiophytina and the broadly distributed mesophilic red algae. Success of the mesophile radiation is surprising given their highly reduced gene inventory. To address this latter issue, we combine an improved genome assembly from the unicellular red alga Porphyridium purpureum with a diverse collection of other algal genomes to reconstruct ancient endosymbiotic gene transfers (EGTs) and gene duplications. We find EGTs associated with the core photosynthetic machinery that may have played important roles in plastid establishment. More significant are the extensive duplications and diversification of nuclear gene families encoding phycobilisome linker proteins that stabilize light-harvesting functions. We speculate that the origin of these complex families in mesophilic red algae may have contributed to their adaptation to a diversity of light environments. Widely distributed red algae have experienced massive genome reduction during evolution. Here, using an improved genome assembly of Porphyridium purpureum, Lee et al. show the role of endosymbiotic gene transfer in plastid evolution and the correlation between phycobilisome linker diversification and the red algal radiation.
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Affiliation(s)
- JunMo Lee
- Department of Biological Sciences, Sungkyunkwan University, Suwon, 16419, Korea.,Department of Biochemistry and Microbiology, Rutgers University, New Brunswick, NJ, 08901, USA.,Department of Oceanography, Kyungpook National University, Daegu, 41566, Korea
| | - Dongseok Kim
- Department of Biological Sciences, Sungkyunkwan University, Suwon, 16419, Korea
| | - Debashish Bhattacharya
- Department of Biochemistry and Microbiology, Rutgers University, New Brunswick, NJ, 08901, USA
| | - Hwan Su Yoon
- Department of Biological Sciences, Sungkyunkwan University, Suwon, 16419, Korea.
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Ponce-Toledo RI, López-García P, Moreira D. Horizontal and endosymbiotic gene transfer in early plastid evolution. THE NEW PHYTOLOGIST 2019; 224:618-624. [PMID: 31135958 PMCID: PMC6759420 DOI: 10.1111/nph.15965] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/30/2018] [Accepted: 05/17/2019] [Indexed: 05/03/2023]
Abstract
Plastids evolved from a cyanobacterium that was engulfed by a heterotrophic eukaryotic host and became a stable organelle. Some of the resulting eukaryotic algae entered into a number of secondary endosymbioses with diverse eukaryotic hosts. These events had major consequences on the evolution and diversification of life on Earth. Although almost all plastid diversity derives from a single endosymbiotic event, the analysis of nuclear genomes of plastid-bearing lineages has revealed a mosaic origin of plastid-related genes. In addition to cyanobacterial genes, plastids recruited for their functioning eukaryotic proteins encoded by the host nucleus and also bacterial proteins of noncyanobacterial origin. Therefore, plastid proteins and plastid-localised metabolic pathways evolved by tinkering and using gene toolkits from different sources. This mixed heritage seems especially complex in secondary algae containing green plastids, the acquisition of which appears to have been facilitated by many previous acquisitions of red algal genes (the 'red carpet hypothesis').
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Affiliation(s)
- Rafael I Ponce-Toledo
- Unité d'Ecologie Systématique et Evolution, CNRS, Université Paris-Sud, AgroParisTech, Université Paris-Saclay, 91400, Orsay, France
| | - Purificación López-García
- Unité d'Ecologie Systématique et Evolution, CNRS, Université Paris-Sud, AgroParisTech, Université Paris-Saclay, 91400, Orsay, France
| | - David Moreira
- Unité d'Ecologie Systématique et Evolution, CNRS, Université Paris-Sud, AgroParisTech, Université Paris-Saclay, 91400, Orsay, France
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Han KY, Maciszewski K, Graf L, Yang JH, Andersen RA, Karnkowska A, Yoon HS. Dictyochophyceae Plastid Genomes Reveal Unusual Variability in Their Organization. JOURNAL OF PHYCOLOGY 2019; 55:1166-1180. [PMID: 31325913 DOI: 10.1111/jpy.12904] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2019] [Accepted: 07/01/2019] [Indexed: 05/22/2023]
Abstract
Dictyochophyceae (silicoflagellates) are unicellular freshwater and marine algae (Heterokontophyta, stramenopiles). Despite their abundance in global oceans and potential ecological significance, discovered in recent years, neither nuclear nor organellar genomes of representatives of this group were sequenced until now. Here, we present the first complete plastid genome sequences of Dictyochophyceae, obtained from four species: Dictyocha speculum, Rhizochromulina marina, Florenciella parvula and Pseudopedinella elastica. Despite their comparable size and genetic content, these four plastid genomes exhibit variability in their organization: plastid genomes of F. parvula and P. elastica possess conventional quadripartite structure with a pair of inverted repeats, R. marina instead possesses two direct repeats with the same orientation and D. speculum possesses no repeats at all. We also observed a number of unusual traits in the plastid genome of D. speculum, including expansion of the intergenic regions, presence of an intron in the otherwise non-intron-bearing psaA gene, and an additional copy of the large subunit of RuBisCO gene (rbcL), the last of which has never been observed in any plastid genome. We conclude that despite noticeable gene content similarities between the plastid genomes of Dictyochophyceae and their relatives (pelagophytes, diatoms), the number of distinctive features observed in this lineage strongly suggests that additional taxa require further investigation.
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Affiliation(s)
- Kwi Young Han
- Department of Biological Science, Sungkyunkwan University, Suwon, 16419, Korea
| | - Kacper Maciszewski
- Department of Molecular Phylogenetics and Evolution, Faculty of Biology, Biological and Chemical Research Centre, University of Warsaw, Żwirki i Wigury 101, 02-089, Warsaw, Poland
| | - Louis Graf
- Department of Biological Science, Sungkyunkwan University, Suwon, 16419, Korea
| | - Ji Hyun Yang
- Department of Biological Science, Sungkyunkwan University, Suwon, 16419, Korea
| | - Robert A Andersen
- Friday Harbor Laboratories, University of Washington, Friday Harbor, Washington, 98250, USA
| | - Anna Karnkowska
- Department of Molecular Phylogenetics and Evolution, Faculty of Biology, Biological and Chemical Research Centre, University of Warsaw, Żwirki i Wigury 101, 02-089, Warsaw, Poland
| | - Hwan Su Yoon
- Department of Biological Science, Sungkyunkwan University, Suwon, 16419, Korea
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38
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Gavelis GS, Gile GH. How did cyanobacteria first embark on the path to becoming plastids?: lessons from protist symbioses. FEMS Microbiol Lett 2019; 365:5079637. [PMID: 30165400 DOI: 10.1093/femsle/fny209] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2018] [Accepted: 08/23/2018] [Indexed: 12/13/2022] Open
Abstract
Symbioses between phototrophs and heterotrophs (a.k.a 'photosymbioses') are extremely common, and range from loose and temporary associations to obligate and highly specialized forms. In the history of life, the most transformative was the 'primary endosymbiosis,' wherein a cyanobacterium was engulfed by a eukaryote and became genetically integrated as a heritable photosynthetic organelle, or plastid. By allowing the rise of algae and plants, this event dramatically altered the biosphere, but its remote origin over one billion years ago has obscured the sequence of events leading to its establishment. Here, we review the genetic, physiological and developmental hurdles involved in early primary endosymbiosis. Since we cannot travel back in time to witness these evolutionary junctures, we will draw on examples of unicellular eukaryotes (protists) spanning diverse modes of photosymbiosis. We also review experimental approaches that could be used to recreate aspects of early primary endosymbiosis on a human timescale.
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Affiliation(s)
- Gregory S Gavelis
- School of Life Sciences, Arizona State University, Room 611, Life Science Tower E, 427 E, Tyler Mall, Tempe, AZ 85287, USA
| | - Gillian H Gile
- School of Life Sciences, Arizona State University, Room 611, Life Science Tower E, 427 E, Tyler Mall, Tempe, AZ 85287, USA
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Dorrell RG, Nisbet RER, Barbrook AC, Rowden SJL, Howe CJ. Integrated Genomic and Transcriptomic Analysis of the Peridinin Dinoflagellate Amphidinium carterae Plastid. Protist 2019; 170:358-373. [PMID: 31415953 DOI: 10.1016/j.protis.2019.06.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2019] [Revised: 06/10/2019] [Accepted: 06/14/2019] [Indexed: 01/17/2023]
Abstract
The plastid genomes of peridinin-containing dinoflagellates are highly unusual, possessing very few genes, which are located on small chromosomal elements termed "minicircles". These minicircles may contain genes, or no recognisable coding information. Transcripts produced from minicircles may undergo unusual processing events, such as the addition of a 3' poly(U) tail. To date, little is known about the genetic or transcriptional diversity of non-coding sequences in peridinin dinoflagellate plastids. These sequences include empty minicircles, and regions of non-coding DNA in coding minicircles. Here, we present an integrated plastid genome and transcriptome for the model peridinin dinoflagellate Amphidinium carterae, identifying a previously undescribed minicircle. We also profile transcripts covering non-coding regions of the psbA and petB/atpA minicircles. We present evidence that antisense transcripts are produced within the A. carterae plastid, but show that these transcripts undergo different end cleavage events from sense transcripts, and do not receive 3' poly(U) tails. The difference in processing events between sense and antisense transcripts may enable the removal of non-coding transcripts from peridinin dinoflagellate plastid transcript pools.
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Affiliation(s)
| | - R Ellen R Nisbet
- Department of Biochemistry, University of Cambridge, United Kingdom
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40
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Gawryluk RMR, Tikhonenkov DV, Hehenberger E, Husnik F, Mylnikov AP, Keeling PJ. Non-photosynthetic predators are sister to red algae. Nature 2019; 572:240-243. [DOI: 10.1038/s41586-019-1398-6] [Citation(s) in RCA: 72] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2019] [Accepted: 06/13/2019] [Indexed: 12/17/2022]
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41
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Hamsher SE, Keepers KG, Pogoda CS, Stepanek JG, Kane NC, Kociolek JP. Extensive chloroplast genome rearrangement amongst three closely related Halamphora spp. (Bacillariophyceae), and evidence for rapid evolution as compared to land plants. PLoS One 2019; 14:e0217824. [PMID: 31269054 PMCID: PMC6608930 DOI: 10.1371/journal.pone.0217824] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2018] [Accepted: 05/21/2019] [Indexed: 01/08/2023] Open
Abstract
Diatoms are the most diverse lineage of algae, but the diversity of their chloroplast genomes, particularly within a genus, has not been well documented. Herein, we present three chloroplast genomes from the genus Halamphora (H. americana, H. calidilacuna, and H. coffeaeformis), the first pennate diatom genus to be represented by more than one species. Halamphora chloroplast genomes ranged in size from ~120 to 150 kb, representing a 24% size difference within the genus. Differences in genome size were due to changes in the length of the inverted repeat region, length of intergenic regions, and the variable presence of ORFs that appear to encode as-yet-undescribed proteins. All three species shared a set of 161 core features but differed in the presence of two genes, serC and tyrC of foreign and unknown origin, respectively. A comparison of these data to three previously published chloroplast genomes in the non-pennate genus Cyclotella (Thalassiosirales) revealed that Halamphora has undergone extensive chloroplast genome rearrangement compared to other genera, as well as containing variation within the genus. Finally, a comparison of Halamphora chloroplast genomes to those of land plants indicates diatom chloroplast genomes within this genus may be evolving at least ~4–7 times faster than those of land plants. Studies such as these provide deeper insights into diatom chloroplast evolution and important genetic resources for future analyses.
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Affiliation(s)
- Sarah E. Hamsher
- Department of Biology, Grand Valley State University, Allendale, Michigan, United States of America
- Annis Water Resources Institute, Grand Valley State University, Muskegon, Michigan, United States of America
- * E-mail:
| | - Kyle G. Keepers
- Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, Colorado, United States of America
| | - Cloe S. Pogoda
- Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, Colorado, United States of America
| | - Joshua G. Stepanek
- Department of Biology, Colorado Mountain College, Edwards, Colorado, United States of America
| | - Nolan C. Kane
- Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, Colorado, United States of America
| | - J. Patrick Kociolek
- Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, Colorado, United States of America
- Museum of Natural History, University of Colorado, Boulder, Colorado, United States of America
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Moreira D, López-García P. Evolution: King-Size Plastid Genomes in a New Red Algal Clade. Curr Biol 2019; 27:R651-R653. [PMID: 28697364 DOI: 10.1016/j.cub.2017.05.038] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
Plastids, the photosynthetic organelles of eukaryotes, exhibit remarkably stable genome architecture. However, a recent study of microscopic red algae has found new record-sized plastid genomes with unusual architectures. These species form a new branch in the tree of red algae.
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Affiliation(s)
- David Moreira
- Ecologie Systématique Evolution, CNRS, Université Paris-Sud, AgroParisTech, Université Paris-Saclay, 91400, Orsay, France.
| | - Purificación López-García
- Ecologie Systématique Evolution, CNRS, Université Paris-Sud, AgroParisTech, Université Paris-Saclay, 91400, Orsay, France
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43
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Ocaña-Pallarès E, Najle SR, Scazzocchio C, Ruiz-Trillo I. Reticulate evolution in eukaryotes: Origin and evolution of the nitrate assimilation pathway. PLoS Genet 2019; 15:e1007986. [PMID: 30789903 PMCID: PMC6400420 DOI: 10.1371/journal.pgen.1007986] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2018] [Revised: 03/05/2019] [Accepted: 01/25/2019] [Indexed: 01/17/2023] Open
Abstract
Genes and genomes can evolve through interchanging genetic material, this leading to reticular evolutionary patterns. However, the importance of reticulate evolution in eukaryotes, and in particular of horizontal gene transfer (HGT), remains controversial. Given that metabolic pathways with taxonomically-patchy distributions can be indicative of HGT events, the eukaryotic nitrate assimilation pathway is an ideal object of investigation, as previous results revealed a patchy distribution and suggested that the nitrate assimilation cluster of dikaryotic fungi (Opisthokonta) could have been originated and transferred from a lineage leading to Oomycota (Stramenopiles). We studied the origin and evolution of this pathway through both multi-scale bioinformatic and experimental approaches. Our taxon-rich genomic screening shows that nitrate assimilation is present in more lineages than previously reported, although being restricted to autotrophs and osmotrophs. The phylogenies indicate a pervasive role of HGT, with three bacterial transfers contributing to the pathway origin, and at least seven well-supported transfers between eukaryotes. In particular, we propose a distinct and more complex HGT path between Opisthokonta and Stramenopiles than the one previously suggested, involving at least two transfers of a nitrate assimilation gene cluster. We also found that gene fusion played an essential role in this evolutionary history, underlying the origin of the canonical eukaryotic nitrate reductase, and of a chimeric nitrate reductase in Ichthyosporea (Opisthokonta). We show that the ichthyosporean pathway, including this novel nitrate reductase, is physiologically active and transcriptionally co-regulated, responding to different nitrogen sources; similarly to distant eukaryotes with independent HGT-acquisitions of the pathway. This indicates that this pattern of transcriptional control evolved convergently in eukaryotes, favoring the proper integration of the pathway in the metabolic landscape. Our results highlight the importance of reticulate evolution in eukaryotes, by showing the crucial contribution of HGT and gene fusion in the evolutionary history of the nitrate assimilation pathway. One of the most relevant findings in evolution was that lineages, either genes or genomes, can evolve through interchanging genetic material. For example, exon shuffling can lead to genes with complete novel functions, and genomes can acquire novel functionalities by means of horizontal gene transfer (HGT). Whereas HGT is known to be an important driver of metabolic remodelling and ecological adaptations in Bacteria, its importance and prevalence in eukaryotes remains controversial. We show that HGT played a major role in the origin and evolution of the eukaryotic nitrate assimilation pathway, with several bacteria-to-eukaryote and eukaryote-to-eukaryote transfers promoting the acquisition of this ecologically-relevant pathway to autotrophs and to distinct groups of osmotrophs. Moreover, we also show that gene fusion was important in this evolutionary history, underlying the origin of the canonical eukaryotic nitrate reductase, but also of a non-canonical nitrate reductase that we describe in Ichthyosporea, a poorly-characterized eukaryotic group that includes many parasitic species. In conclusion, our results highlight the importance of reticulate evolution in eukaryotes, by showing the contribution of HGT and gene fusion in the evolutionary history of the nitrate assimilation pathway.
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Affiliation(s)
- Eduard Ocaña-Pallarès
- Institut de Biologia Evolutiva (CSIC-Universitat Pompeu Fabra), Barcelona, Catalonia, Spain
- * E-mail: (EOP); (IRT)
| | - Sebastián R. Najle
- Institut de Biologia Evolutiva (CSIC-Universitat Pompeu Fabra), Barcelona, Catalonia, Spain
- Instituto de Biología Molecular y Celular de Rosario (IBR-CONICET) and Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Ocampo y Esmeralda s/n, Rosario S2000FHQ, Argentina
| | - Claudio Scazzocchio
- Department of Microbiology, Imperial College, London, United Kingdom
- Institute for Integrative Biology of the Cell (I2BC), Gif-sur-Yvette, France
| | - Iñaki Ruiz-Trillo
- Institut de Biologia Evolutiva (CSIC-Universitat Pompeu Fabra), Barcelona, Catalonia, Spain
- Departament de Genètica, Microbiologia i Estadística, Facultat de Biologia, Institut de Recerca de la Biodiversitat (IRBio), Universitat de Barcelona (UB), Barcelona, Catalonia, Spain
- ICREA, Barcelona, Catalonia, Spain
- * E-mail: (EOP); (IRT)
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44
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Figueroa-Martinez F, Jackson C, Reyes-Prieto A. Plastid Genomes from Diverse Glaucophyte Genera Reveal a Largely Conserved Gene Content and Limited Architectural Diversity. Genome Biol Evol 2019; 11:174-188. [PMID: 30534986 PMCID: PMC6330054 DOI: 10.1093/gbe/evy268] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/10/2018] [Indexed: 12/30/2022] Open
Abstract
Plastid genome (ptDNA) data of Glaucophyta have been limited for many years to the genus Cyanophora. Here, we sequenced the ptDNAs of Gloeochaete wittrockiana, Cyanoptyche gloeocystis, Glaucocystis incrassata, and Glaucocystis sp. BBH. The reported sequences are the first genome-scale plastid data available for these three poorly studied glaucophyte genera. Although the Glaucophyta plastids appear morphologically “ancestral,” they actually bear derived genomes not radically different from those of red algae or viridiplants. The glaucophyte plastid coding capacity is highly conserved (112 genes shared) and the architecture of the plastid chromosomes is relatively simple. Phylogenomic analyses recovered Glaucophyta as the earliest diverging Archaeplastida lineage, but the position of viridiplants as the first branching group was not rejected by the approximately unbiased test. Pairwise distances estimated from 19 different plastid genes revealed that the highest sequence divergence between glaucophyte genera is frequently higher than distances between species of different classes within red algae or viridiplants. Gene synteny and sequence similarity in the ptDNAs of the two Glaucocystis species analyzed is conserved. However, the ptDNA of Gla. incrassata contains a 7.9-kb insertion not detected in Glaucocystis sp. BBH. The insertion contains ten open reading frames that include four coding regions similar to bacterial serine recombinases (two open reading frames), DNA primases, and peptidoglycan aminohydrolases. These three enzymes, often encoded in bacterial plasmids and bacteriophage genomes, are known to participate in the mobilization and replication of DNA mobile elements. It is therefore plausible that the insertion in Gla. incrassata ptDNA is derived from a DNA mobile element.
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Affiliation(s)
- Francisco Figueroa-Martinez
- Department of Biology, University of New Brunswick, Fredericton, New Brunswick, Canada.,CONACyT-Universidad Autónoma Metropolitana Iztapalapa, Biotechnology Department, Mexico City, Mexico
| | - Christopher Jackson
- Department of Biology, University of New Brunswick, Fredericton, New Brunswick, Canada.,School of Biosciences, University of Melbourne, Melbourne, Australia
| | - Adrian Reyes-Prieto
- Department of Biology, University of New Brunswick, Fredericton, New Brunswick, Canada
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45
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Lee J. Plasmid-Associated Organelle Genome Evolution In Red Algae. JOURNAL OF PHYCOLOGY 2018; 54:772-774. [PMID: 30614001 DOI: 10.1111/jpy.12797] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Affiliation(s)
- JunMo Lee
- Department of Biological Sciences, Sungkyunkwan University, Seobu-ro 2066, Jangan-gu, Suwon, 16419, Korea
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46
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Lee JM, Song HJ, Park SI, Lee YM, Jeong SY, Cho TO, Kim JH, Choi HG, Choi CG, Nelson WA, Fredericq S, Bhattacharya D, Yoon HS. Mitochondrial and Plastid Genomes from Coralline Red Algae Provide Insights into the Incongruent Evolutionary Histories of Organelles. Genome Biol Evol 2018; 10:2961-2972. [PMID: 30364957 PMCID: PMC6279150 DOI: 10.1093/gbe/evy222] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/27/2018] [Indexed: 11/14/2022] Open
Abstract
Mitochondria and plastids are generally uniparentally inherited and have a conserved gene content over hundreds of millions of years, which makes them potentially useful phylogenetic markers. Organelle single gene-based trees have long been the basis for elucidating interspecies relationships that inform taxonomy. More recently, high-throughput genome sequencing has enabled the construction of massive organelle genome databases from diverse eukaryotes, and these have been used to infer species relationships in deep evolutionary time. Here, we test the idea that despite their expected utility, conflicting phylogenetic signal may exist in mitochondrial and plastid genomes from the anciently diverged coralline red algae (Rhodophyta). We generated complete organelle genome data from five coralline red algae (Lithothamnion sp., Neogoniolithon spectabile, Renouxia sp., Rhodogorgon sp., and Synarthrophyton chejuensis) for comparative analysis with existing organelle genome data from two other species (Calliarthron tuberculosum and Sporolithon durum). We find strong evidence for incongruent phylogenetic signal from both organelle genomes that may be explained by incomplete lineage sorting that has maintained anciently derived gene copies or other molecular evolutionary processes such as hybridization or gene flow during the evolutionary history of coralline red algae.
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Affiliation(s)
- Jun Mo Lee
- Department of Biological Sciences, Sungkyunkwan University, Suwon, Korea
| | - Hae Jung Song
- Department of Biological Sciences, Sungkyunkwan University, Suwon, Korea
| | - Seung In Park
- Department of Biological Sciences, Sungkyunkwan University, Suwon, Korea
| | - Yu Min Lee
- Department of Biological Sciences, Sungkyunkwan University, Suwon, Korea
| | - So Young Jeong
- Department of Marine Life Science, Chosun University, Gwangju, Korea
| | - Tae Oh Cho
- Department of Marine Life Science, Chosun University, Gwangju, Korea
| | - Ji Hee Kim
- Division of Life Sciences, Korea Polar Research Institute, KOPRI, Incheon, Korea
| | - Han-Gu Choi
- Division of Life Sciences, Korea Polar Research Institute, KOPRI, Incheon, Korea
| | - Chang Geun Choi
- Department of Ecological Engineering, Pukyong National University, Busan, Korea
| | - Wendy A Nelson
- National Institute for Water and Atmospheric Research, Wellington, New Zealand.,School of Biological Sciences, University of Auckland, New Zealand
| | - Suzanne Fredericq
- Biology Department, University of Louisiana at Lafayette, Lafayette, Louisiana
| | | | - Hwan Su Yoon
- Department of Biological Sciences, Sungkyunkwan University, Suwon, Korea
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47
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Lukeš J, Wheeler R, Jirsová D, David V, Archibald JM. Massive mitochondrial DNA content in diplonemid and kinetoplastid protists. IUBMB Life 2018; 70:1267-1274. [PMID: 30291814 PMCID: PMC6334171 DOI: 10.1002/iub.1894] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2018] [Revised: 06/11/2018] [Accepted: 06/12/2018] [Indexed: 11/25/2022]
Abstract
The mitochondrial DNA of diplonemid and kinetoplastid protists is known for its suite of bizarre features, including the presence of concatenated circular molecules, extensive trans‐splicing and various forms of RNA editing. Here we report on the existence of another remarkable characteristic: hyper‐inflated DNA content. We estimated the total amount of mitochondrial DNA in four kinetoplastid species (Trypanosoma brucei, Trypanoplasma borreli, Cryptobia helicis, and Perkinsela sp.) and the diplonemid Diplonema papillatum. Staining with 4′,6‐diamidino‐2‐phenylindole and RedDot1 followed by color deconvolution and quantification revealed massive inflation in the total amount of DNA in their organelles. This was further confirmed by electron microscopy. The most extreme case is the ∼260 Mbp of DNA in the mitochondrion of Diplonema, which greatly exceeds that in its nucleus; this is, to our knowledge, the largest amount of DNA described in any organelle. Perkinsela sp. has a total mitochondrial DNA content ~6.6× greater than its nuclear genome. This mass of DNA occupies most of the volume of the Perkinsela cell, despite the fact that it contains only six protein‐coding genes. Why so much DNA? We propose that these bloated mitochondrial DNAs accumulated by a ratchet‐like process. Despite their excessive nature, the synthesis and maintenance of these mtDNAs must incur a relatively low cost, considering that diplonemids are one of the most ubiquitous and speciose protist groups in the ocean. © 2018 The Authors. IUBMB Life published by Wiley Periodicals, Inc. on behalf of International Union of Biochemistry and Molecular Biology., 70(12):1267–1274, 2018
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Affiliation(s)
- Julius Lukeš
- Institute of ParasitologyBiology Centre, Czech Academy of SciencesČeské Budějovice (Budweis)Czech Republic
- Faculty of ScienceUniversity of South BohemiaČeské Budějovice (Budweis)Czech Republic
| | - Richard Wheeler
- Sir William Dunn School of PathologyUniversity of OxfordOxfordUK
| | - Dagmar Jirsová
- Institute of ParasitologyBiology Centre, Czech Academy of SciencesČeské Budějovice (Budweis)Czech Republic
| | - Vojtěch David
- Department of Biochemistry and Molecular BiologyDalhousie UniversityHalifaxCanada
| | - John M. Archibald
- Department of Biochemistry and Molecular BiologyDalhousie UniversityHalifaxCanada
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48
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Cremen MCM, Leliaert F, Marcelino VR, Verbruggen H. Large Diversity of Nonstandard Genes and Dynamic Evolution of Chloroplast Genomes in Siphonous Green Algae (Bryopsidales, Chlorophyta). Genome Biol Evol 2018; 10:1048-1061. [PMID: 29635329 PMCID: PMC5888179 DOI: 10.1093/gbe/evy063] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/14/2018] [Indexed: 12/15/2022] Open
Abstract
Chloroplast genomes have undergone tremendous alterations through the evolutionary history of the green algae (Chloroplastida). This study focuses on the evolution of chloroplast genomes in the siphonous green algae (order Bryopsidales). We present five new chloroplast genomes, which along with existing sequences, yield a data set representing all but one families of the order. Using comparative phylogenetic methods, we investigated the evolutionary dynamics of genomic features in the order. Our results show extensive variation in chloroplast genome architecture and intron content. Variation in genome size is accounted for by the amount of intergenic space and freestanding open reading frames that do not show significant homology to standard plastid genes. We show the diversity of these nonstandard genes based on their conserved protein domains, which are often associated with mobile functions (reverse transcriptase/intron maturase, integrases, phage- or plasmid-DNA primases, transposases, integrases, ligases). Investigation of the introns showed proliferation of group II introns in the early evolution of the order and their subsequent loss in the core Halimedineae, possibly through RT-mediated intron loss.
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Affiliation(s)
| | - Frederik Leliaert
- Botanic Garden Meise, 1860 Meise, Belgium.,Department of Biology, Phycology Research Group, Ghent University, 9000 Ghent, Belgium
| | - Vanessa R Marcelino
- School of BioSciences, University of Melbourne, Parkville, Australia.,Centre for Infectious Diseases and Microbiology, Westmead Institute for Medical Research, and Marie Bashir Institute for Infectious Diseases and Biosecurity, University of Sydney, New South Wales, Australia
| | - Heroen Verbruggen
- School of BioSciences, University of Melbourne, Parkville, Australia
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Gaouda H, Hamaji T, Yamamoto K, Kawai-Toyooka H, Suzuki M, Noguchi H, Minakuchi Y, Toyoda A, Fujiyama A, Nozaki H, Smith DR. Exploring the Limits and Causes of Plastid Genome Expansion in Volvocine Green Algae. Genome Biol Evol 2018; 10:2248-2254. [PMID: 30102347 PMCID: PMC6128376 DOI: 10.1093/gbe/evy175] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/07/2018] [Indexed: 12/25/2022] Open
Abstract
Plastid genomes are not normally celebrated for being large. But researchers are steadily uncovering algal lineages with big and, in rare cases, enormous plastid DNAs (ptDNAs), such as volvocine green algae. Plastome sequencing of five different volvocine species has revealed some of the largest, most repeat-dense plastomes on record, including that of Volvox carteri (∼525 kb). Volvocine algae have also been used as models for testing leading hypotheses on organelle genome evolution (e.g., the mutational hazard hypothesis), and it has been suggested that ptDNA inflation within this group might be a consequence of low mutation rates and/or the transition from a unicellular to multicellular existence. Here, we further our understanding of plastome size variation in the volvocine line by examining the ptDNA sequences of the colonial species Yamagishiella unicocca and Eudorina sp. NIES-3984 and the multicellular Volvox africanus, which are phylogenetically situated between species with known ptDNA sizes. Although V. africanus is closely related and similar in multicellular organization to V. carteri, its ptDNA was much less inflated than that of V. carteri. Synonymous- and noncoding-site nucleotide substitution rate analyses of these two Volvox ptDNAs suggest that there are drastically different plastid mutation rates operating in the coding versus intergenic regions, supporting the idea that error-prone DNA repair in repeat-rich intergenic spacers is contributing to genome expansion. Our results reinforce the idea that the volvocine line harbors extremes in plastome size but ultimately shed doubt on some of the previously proposed hypotheses for ptDNA inflation within the lineage.
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Affiliation(s)
- Hager Gaouda
- Department of Biology, University of Western Ontario, London, Ontario, Canada
| | - Takashi Hamaji
- Department of Biological Sciences, Graduate School of Science, University of Tokyo, Japan
- Department of Biological Sciences, Graduate School of Science, Kyoto University, Japan
| | - Kayoko Yamamoto
- Department of Biological Sciences, Graduate School of Science, University of Tokyo, Japan
| | - Hiroko Kawai-Toyooka
- Department of Biological Sciences, Graduate School of Science, University of Tokyo, Japan
| | - Masahiro Suzuki
- Kobe University Research Center for Inland Seas, Awaji, Hyogo, Japan
| | - Hideki Noguchi
- Center for Genome Informatics, Joint Support-Center for Data Science Research, Research Organization of Information and Systems, Mishima, Shizuoka, Japan
- Advanced Genomics Center, National Institute of Genetics, Mishima, Shizuoka, Japan
| | - Yohei Minakuchi
- Center for Information Biology, National Institute of Genetics, Mishima, Shizuoka, Japan
| | - Atsushi Toyoda
- Advanced Genomics Center, National Institute of Genetics, Mishima, Shizuoka, Japan
- Center for Information Biology, National Institute of Genetics, Mishima, Shizuoka, Japan
| | - Asao Fujiyama
- Advanced Genomics Center, National Institute of Genetics, Mishima, Shizuoka, Japan
| | - Hisayoshi Nozaki
- Department of Biological Sciences, Graduate School of Science, University of Tokyo, Japan
| | - David Roy Smith
- Department of Biology, University of Western Ontario, London, Ontario, Canada
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Complex Analyses of Short Inverted Repeats in All Sequenced Chloroplast DNAs. BIOMED RESEARCH INTERNATIONAL 2018; 2018:1097018. [PMID: 30140690 PMCID: PMC6081594 DOI: 10.1155/2018/1097018] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/15/2018] [Revised: 06/19/2018] [Accepted: 07/12/2018] [Indexed: 01/14/2023]
Abstract
Chloroplasts are key organelles in the management of oxygen in algae and plants and are therefore crucial for all living beings that consume oxygen. Chloroplasts typically contain a circular DNA molecule with nucleus-independent replication and heredity. Using "palindrome analyser" we performed complete analyses of short inverted repeats (S-IRs) in all chloroplast DNAs (cpDNAs) available from the NCBI genome database. Our results provide basic parameters of cpDNAs including comparative information on localization, frequency, and differences in S-IR presence. In a total of 2,565 cpDNA sequences available, the average frequency of S-IRs in cpDNA genomes is 45 S-IRs/per kbp, significantly higher than that found in mitochondrial DNA sequences. The frequency of S-IRs in cpDNAs generally decreased with S-IR length, but not for S-IRs 15, 22, 24, or 27 bp long, which are significantly more abundant than S-IRs with other lengths. These results point to the importance of specific S-IRs in cpDNA genomes. Moreover, comparison by Levenshtein distance of S-IR similarities showed that a limited number of S-IR sequences are shared in the majority of cpDNAs. S-IRs are not located randomly in cpDNAs, but are length-dependently enriched in specific locations, including the repeat region, stem, introns, and tRNA regions. The highest enrichment was found for 12 bp and longer S-IRs in the stem-loop region followed by 12 bp and longer S-IRs located before the repeat region. On the other hand, S-IRs are relatively rare in rRNA sequences and around introns. These data show nonrandom and conserved arrangements of S-IRs in chloroplast genomes.
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