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Lax G, Okamoto N, Keeling PJ. Phylogenomic position of eupelagonemids, abundant, and diverse deep-ocean heterotrophs. ISME J 2024; 18:wrae040. [PMID: 38457644 PMCID: PMC10987973 DOI: 10.1093/ismejo/wrae040] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2023] [Revised: 02/02/2024] [Accepted: 03/06/2024] [Indexed: 03/10/2024]
Abstract
Eupelagonemids, formerly known as Deep Sea Pelagic Diplonemids I (DSPD I), are among the most abundant and diverse heterotrophic protists in the deep ocean, but little else is known about their ecology, evolution, or biology in general. Originally recognized solely as a large clade of environmental ribosomal subunit RNA gene sequences (SSU rRNA), branching with a smaller sister group DSPD II, they were postulated to be diplonemids, a poorly studied branch of Euglenozoa. Although new diplonemids have been cultivated and studied in depth in recent years, the lack of cultured eupelagonemids has limited data to a handful of light micrographs, partial SSU rRNA gene sequences, a small number of genes from single amplified genomes, and only a single formal described species, Eupelagonema oceanica. To determine exactly where this clade goes in the tree of eukaryotes and begin to address the overall absence of biological information about this apparently ecologically important group, we conducted single-cell transcriptomics from two eupelagonemid cells. A SSU rRNA gene phylogeny shows that these two cells represent distinct subclades within eupelagonemids, each different from E. oceanica. Phylogenomic analysis based on a 125-gene matrix contrasts with the findings based on ecological survey data and shows eupelagonemids branch sister to the diplonemid subgroup Hemistasiidae.
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Affiliation(s)
- Gordon Lax
- Department of Botany, University of British Columbia, Vancouver, BC, V6T 1Z4, Canada
| | - Noriko Okamoto
- Department of Botany, University of British Columbia, Vancouver, BC, V6T 1Z4, Canada
- Hakai Institute, Heriot Bay, BC, V0P 1H0, Canada
| | - Patrick J Keeling
- Department of Botany, University of British Columbia, Vancouver, BC, V6T 1Z4, Canada
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Valach M, Benz C, Aguilar LC, Gahura O, Faktorová D, Zíková A, Oeffinger M, Burger G, Gray MW, Lukeš J. Miniature RNAs are embedded in an exceptionally protein-rich mitoribosome via an elaborate assembly pathway. Nucleic Acids Res 2023; 51:6443-6460. [PMID: 37207340 PMCID: PMC10325924 DOI: 10.1093/nar/gkad422] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Revised: 04/20/2023] [Accepted: 05/08/2023] [Indexed: 05/21/2023] Open
Abstract
The mitochondrial ribosome (mitoribosome) has diverged drastically from its evolutionary progenitor, the bacterial ribosome. Structural and compositional diversity is particularly striking in the phylum Euglenozoa, with an extraordinary protein gain in the mitoribosome of kinetoplastid protists. Here we report an even more complex mitoribosome in diplonemids, the sister-group of kinetoplastids. Affinity pulldown of mitoribosomal complexes from Diplonema papillatum, the diplonemid type species, demonstrates that they have a mass of > 5 MDa, contain as many as 130 integral proteins, and exhibit a protein-to-RNA ratio of 11:1. This unusual composition reflects unprecedented structural reduction of ribosomal RNAs, increased size of canonical mitoribosomal proteins, and accretion of three dozen lineage-specific components. In addition, we identified >50 candidate assembly factors, around half of which contribute to early mitoribosome maturation steps. Because little is known about early assembly stages even in model organisms, our investigation of the diplonemid mitoribosome illuminates this process. Together, our results provide a foundation for understanding how runaway evolutionary divergence shapes both biogenesis and function of a complex molecular machine.
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Affiliation(s)
- Matus Valach
- Department of Biochemistry and Robert-Cedergren Centre for Bioinformatics and Genomics, Université de Montréal, Montréal, Quebec, Canada
| | - Corinna Benz
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, České Budějovice (Budweis), Czech Republic
| | - Lisbeth C Aguilar
- Center for Genetic and Neurological Diseases, Institut de recherches cliniques de Montréal (IRCM), Montréal, Quebec, Canada
| | - Ondřej Gahura
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, České Budějovice (Budweis), Czech Republic
| | - Drahomíra Faktorová
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, České Budějovice (Budweis), Czech Republic
- Faculty of Sciences, University of South Bohemia, České Budějovice (Budweis), Czech Republic
| | - Alena Zíková
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, České Budějovice (Budweis), Czech Republic
- Faculty of Sciences, University of South Bohemia, České Budějovice (Budweis), Czech Republic
| | - Marlene Oeffinger
- Department of Biochemistry and Robert-Cedergren Centre for Bioinformatics and Genomics, Université de Montréal, Montréal, Quebec, Canada
- Center for Genetic and Neurological Diseases, Institut de recherches cliniques de Montréal (IRCM), Montréal, Quebec, Canada
- Division of Experimental Medicine, McGill University, Montréal, Quebec, Canada
| | - Gertraud Burger
- Department of Biochemistry and Robert-Cedergren Centre for Bioinformatics and Genomics, Université de Montréal, Montréal, Quebec, Canada
| | - Michael W Gray
- Department of Biochemistry and Molecular Biology and Institute of Comparative Genomics, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Julius Lukeš
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, České Budějovice (Budweis), Czech Republic
- Faculty of Sciences, University of South Bohemia, České Budějovice (Budweis), Czech Republic
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Škodová-Sveráková I, Záhonová K, Juricová V, Danchenko M, Moos M, Baráth P, Prokopchuk G, Butenko A, Lukáčová V, Kohútová L, Bučková B, Horák A, Faktorová D, Horváth A, Šimek P, Lukeš J. Highly flexible metabolism of the marine euglenozoan protist Diplonema papillatum. BMC Biol 2021; 19:251. [PMID: 34819072 PMCID: PMC8611851 DOI: 10.1186/s12915-021-01186-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Accepted: 11/08/2021] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND The phylum Euglenozoa is a group of flagellated protists comprising the diplonemids, euglenids, symbiontids, and kinetoplastids. The diplonemids are highly abundant and speciose, and recent tools have rendered the best studied representative, Diplonema papillatum, genetically tractable. However, despite the high diversity of diplonemids, their lifestyles, ecological functions, and even primary energy source are mostly unknown. RESULTS We designed a metabolic map of D. papillatum cellular bioenergetic pathways based on the alterations of transcriptomic, proteomic, and metabolomic profiles obtained from cells grown under different conditions. Comparative analysis in the nutrient-rich and nutrient-poor media, as well as the absence and presence of oxygen, revealed its capacity for extensive metabolic reprogramming that occurs predominantly on the proteomic rather than the transcriptomic level. D. papillatum is equipped with fundamental metabolic routes such as glycolysis, gluconeogenesis, TCA cycle, pentose phosphate pathway, respiratory complexes, β-oxidation, and synthesis of fatty acids. Gluconeogenesis is uniquely dominant over glycolysis under all surveyed conditions, while the TCA cycle represents an eclectic combination of standard and unusual enzymes. CONCLUSIONS The identification of conventional anaerobic enzymes reflects the ability of this protist to survive in low-oxygen environments. Furthermore, its metabolism quickly reacts to restricted carbon availability, suggesting a high metabolic flexibility of diplonemids, which is further reflected in cell morphology and motility, correlating well with their extreme ecological valence.
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Affiliation(s)
- Ingrid Škodová-Sveráková
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, České Budějovice (Budweis), Czech Republic.
- Faculty of Natural Sciences, Comenius University, Bratislava, Slovakia.
| | - Kristína Záhonová
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, České Budějovice (Budweis), Czech Republic
- Faculty of Science, Charles University, BIOCEV, Vestec, Czech Republic
| | - Valéria Juricová
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, České Budějovice (Budweis), Czech Republic
- Faculty of Sciences, University of South Bohemia, České Budějovice (Budweis), Czech Republic
| | - Maksym Danchenko
- Institute of Chemistry, Slovak Academy of Sciences, Bratislava, Slovakia
| | - Martin Moos
- Institute of Entomology, Biology Centre, Czech Academy of Sciences, České Budějovice (Budweis), Czech Republic
| | - Peter Baráth
- Institute of Chemistry, Slovak Academy of Sciences, Bratislava, Slovakia
- Medirex Group Academy n.o., Trnava, Slovakia
| | - Galina Prokopchuk
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, České Budějovice (Budweis), Czech Republic
| | - Anzhelika Butenko
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, České Budějovice (Budweis), Czech Republic
- Faculty of Science, University of Ostrava, Ostrava, Czech Republic
| | | | - Lenka Kohútová
- Institute of Chemistry, Slovak Academy of Sciences, Bratislava, Slovakia
| | - Barbora Bučková
- Faculty of Natural Sciences, Comenius University, Bratislava, Slovakia
| | - Aleš Horák
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, České Budějovice (Budweis), Czech Republic
- Faculty of Sciences, University of South Bohemia, České Budějovice (Budweis), Czech Republic
| | - Drahomíra Faktorová
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, České Budějovice (Budweis), Czech Republic
- Faculty of Sciences, University of South Bohemia, České Budějovice (Budweis), Czech Republic
| | - Anton Horváth
- Faculty of Natural Sciences, Comenius University, Bratislava, Slovakia
| | - Petr Šimek
- Institute of Entomology, Biology Centre, Czech Academy of Sciences, České Budějovice (Budweis), Czech Republic
| | - Julius Lukeš
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, České Budějovice (Budweis), Czech Republic.
- Faculty of Sciences, University of South Bohemia, České Budějovice (Budweis), Czech Republic.
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Yabuki A, Kawato M, Nagano Y, Tsuchida S, Yoshida T, Fujiwara Y. Structural Comparison of Diplonemid Communities around the Izu Peninsula, Japan. Microbes Environ 2021; 36:ME21012. [PMID: 34121037 PMCID: PMC8209450 DOI: 10.1264/jsme2.me21012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2021] [Accepted: 05/07/2021] [Indexed: 11/28/2022] Open
Abstract
Diplonemea (diplonemids) is one of the most abundant and species-rich protist groups in marine environments; however, their community structures among local and seasonal samples have not yet been compared. In the present study, we analyzed four diplonemid community structures around the Izu Peninsula, Japan using barcode sequences amplified from environmental DNA. These sequences and the results of statistical analyses indicated that communities at the same site were more similar to each other than those in the same season. Environmental variables were also measured, and their influence on diplonemid community structures was examined. Salinity, electrical conductivity, and temperature, and their correlated variables, appeared to influence the structures of diplonemid communities, which was consistent with previous findings; however, since the results obtained did not reach statistical significance, further studies are required. A comparison of each diplonemid community indicated that some lineages were unique to specific samples, while others were consistently detected in all samples. Members of the latter type are cosmopolitan candidates and may be better adapted to the environments of the studied area. Future studies that focus on the more adaptive members will provide a more detailed understanding of the mechanisms by which diplonemids are widely distributed in marine environments and will facilitate their utilization as indicator organisms to monitor environmental changes.
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Affiliation(s)
- Akinori Yabuki
- Deep-Sea Biodiversity Research Group, Research Institute for Global Change, Japan Agency for Marine-Earth Science and Technology (JAMSTEC), 2–15 Natsushima, Yokosuka, Kanagawa 2370061, Japan
| | - Masaru Kawato
- Deep-Sea Biodiversity Research Group, Research Institute for Global Change, Japan Agency for Marine-Earth Science and Technology (JAMSTEC), 2–15 Natsushima, Yokosuka, Kanagawa 2370061, Japan
| | - Yuriko Nagano
- Deep-Sea Biodiversity Research Group, Research Institute for Global Change, Japan Agency for Marine-Earth Science and Technology (JAMSTEC), 2–15 Natsushima, Yokosuka, Kanagawa 2370061, Japan
| | - Shinji Tsuchida
- Deep-Sea Biodiversity Research Group, Research Institute for Global Change, Japan Agency for Marine-Earth Science and Technology (JAMSTEC), 2–15 Natsushima, Yokosuka, Kanagawa 2370061, Japan
| | - Takao Yoshida
- Deep-Sea Biodiversity Research Group, Research Institute for Global Change, Japan Agency for Marine-Earth Science and Technology (JAMSTEC), 2–15 Natsushima, Yokosuka, Kanagawa 2370061, Japan
| | - Yoshihiro Fujiwara
- Deep-Sea Biodiversity Research Group, Research Institute for Global Change, Japan Agency for Marine-Earth Science and Technology (JAMSTEC), 2–15 Natsushima, Yokosuka, Kanagawa 2370061, Japan
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Butenko A, Hammond M, Field MC, Ginger ML, Yurchenko V, Lukeš J. Reductionist Pathways for Parasitism in Euglenozoans? Expanded Datasets Provide New Insights. Trends Parasitol 2020; 37:100-116. [PMID: 33127331 DOI: 10.1016/j.pt.2020.10.001] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2020] [Revised: 09/30/2020] [Accepted: 10/01/2020] [Indexed: 12/21/2022]
Abstract
The unicellular trypanosomatids belong to the phylum Euglenozoa and all known species are obligate parasites. Distinct lineages infect plants, invertebrates, and vertebrates, including humans. Genome data for marine diplonemids, together with freshwater euglenids and free-living kinetoplastids, the closest known nonparasitic relatives to trypanosomatids, recently became available. Robust phylogenetic reconstructions across Euglenozoa are now possible and place the results of parasite-focused studies into an evolutionary context. Here we discuss recent advances in identifying the factors shaping the evolution of Euglenozoa, focusing on ancestral features generally considered parasite-specific. Remarkably, most of these predate the transition(s) to parasitism, suggesting that the presence of certain preconditions makes a significant lifestyle change more likely.
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Affiliation(s)
- Anzhelika Butenko
- Biology Centre, Institute of Parasitology, Czech Academy of Sciences, České Budějovice (Budweis), Czech Republic; Faculty of Science, University of Ostrava, Ostrava, Czech Republic.
| | - Michael Hammond
- Biology Centre, Institute of Parasitology, Czech Academy of Sciences, České Budějovice (Budweis), Czech Republic
| | - Mark C Field
- Biology Centre, Institute of Parasitology, Czech Academy of Sciences, České Budějovice (Budweis), Czech Republic; School of Life Sciences, University of Dundee, Dundee, UK
| | - Michael L Ginger
- School of Applied Sciences, University of Huddersfield, Huddersfield, UK
| | - Vyacheslav Yurchenko
- Faculty of Science, University of Ostrava, Ostrava, Czech Republic; Martsinovsky Institute of Medical Parasitology, Sechenov University, Moscow, Russia
| | - Julius Lukeš
- Biology Centre, Institute of Parasitology, Czech Academy of Sciences, České Budějovice (Budweis), Czech Republic; Faculty of Sciences, University of South Bohemia, České Budějovice (Budweis), Czech Republic.
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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: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [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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Lakey B, Triemer R. The tetrapyrrole synthesis pathway as a model of horizontal gene transfer in euglenoids. J Phycol 2017; 53:198-217. [PMID: 27859237 DOI: 10.1111/jpy.12491] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/23/2015] [Accepted: 09/14/2016] [Indexed: 06/06/2023]
Abstract
The history of euglenoids may have begun as early as ~2 bya. These early phagotrophs ate cyanobacteria, archaea, and eubacteria, and the subsequent appearance of red algae and chromalveolates provided euglenoids with additional food sources. Following the appearance of green algae, euglenoids acquired a chloroplast via a secondary endosymbiotic event with a green algal ancestor. This endosymbiosis also involved a massive transfer of nuclear-encoded genes from the symbiont nucleus to the host. Expecting these genes to have a green algal origin, this research has shown, through the use of DNA-sequences and the analysis of phylogenetic relationships, that many housekeeping genes have a red algal/chromalveolate ancestry. This suggested that many other endosymbiotic/horizontal gene transfers, which brought genes from chromalveolates to euglenoids, may have been taking place long before the acquisition of the chloroplast. The investigation of the origin of the enzymes involved in the tetrapyrrole synthesis pathway provided insights into horizontal gene transfer in euglenoids and demonstrated that the euglenoid nuclear genome is a mosaic comprised of genes from the ancestral lineage plus genes transferred endosymbiotically/horizontally from green, red, and chromalveolates lineages.
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Affiliation(s)
- Bryan Lakey
- Department of Plant Biology, Michigan State University, 612 Wilson Rd, 166 Plant Biology Labs, East Lansing, Michigan, 48824, USA
| | - Richard Triemer
- Department of Plant Biology, Michigan State University, 612 Wilson Rd, 166 Plant Biology Labs, East Lansing, Michigan, 48824, USA
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Yamaguchi A, Yubuki N, Leander BS. Morphostasis in a novel eukaryote illuminates the evolutionary transition from phagotrophy to phototrophy: description of Rapaza viridis n. gen. et sp. (Euglenozoa, Euglenida). BMC Evol Biol 2012; 12:29. [PMID: 22401606 PMCID: PMC3374381 DOI: 10.1186/1471-2148-12-29] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2011] [Accepted: 03/08/2012] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Morphostasis of traits in different species is necessary for reconstructing the evolutionary history of complex characters. Studies that place these species into a molecular phylogenetic context test hypotheses about the transitional stages that link divergent character states. For instance, the transition from a phagotrophic mode of nutrition to a phototrophic lifestyle has occurred several times independently across the tree of eukaryotes; one of these events took place within the Euglenida, a large group of flagellates with diverse modes of nutrition. Phototrophic euglenids form a clade that is nested within lineages of phagotrophic euglenids and that originated through a secondary endosymbiosis with green algae. Although it is clear that phototrophic euglenids evolved from phagotrophic ancestors, the morphological disparity between species representing these different nutritional modes remains substantial. RESULTS We cultivated a novel marine euglenid, Rapaza viridis n. gen. et sp. ("green grasper"), and a green alga, Tetraselmis sp., from the same environment. Cells of R. viridis were comprehensively characterized with light microscopy, SEM, TEM, and molecular phylogenetic analysis of small subunit rDNA sequences. Ultrastructural and behavioral observations demonstrated that this isolate habitually consumes a specific strain of Tetraselmis prey cells and possesses a functional chloroplast that is homologous with other phototrophic euglenids. A novel feeding apparatus consisting of a reduced rod of microtubules facilitated this first and only example of mixotrophy among euglenids. R. viridis also possessed a robust photoreception apparatus, two flagella of unequal length, euglenoid movement, and a pellicle consisting of 16 strips and one (square-shaped) whorl of posterior strip reduction. The molecular phylogenetic data demonstrated that R. viridis branches as the nearest sister lineage to phototrophic euglenids. CONCLUSIONS The unusual combination of features in R. viridis combined with its molecular phylogenetic position completely conforms to the expected transitional stage that occurred during the early evolution of phototrophic euglenids from phagotrophic ancestors. The marine mixotrophic mode of nutrition, the preference for green algal prey cells, the structure of the feeding apparatus, and the organization of the pellicle are outstanding examples of morphostasis that clarify pivotal stages in the evolutionary history of this diverse group of microbial eukaryotes.
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Affiliation(s)
- Aika Yamaguchi
- The Department of Botany and Zoology, Beaty Biodiversity Research Center and Museum, University of British Columbia, 6270 University Blvd., Vancouver, British ColumbiaV6T 1Z4, Canada
| | - Naoji Yubuki
- The Department of Botany and Zoology, Beaty Biodiversity Research Center and Museum, University of British Columbia, 6270 University Blvd., Vancouver, British ColumbiaV6T 1Z4, Canada
| | - Brian S Leander
- The Department of Botany and Zoology, Beaty Biodiversity Research Center and Museum, University of British Columbia, 6270 University Blvd., Vancouver, British ColumbiaV6T 1Z4, Canada
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Affiliation(s)
- Dave Speijer
- Department of Medical Biochemistry, Academic Medical Center (AMC), University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
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