DOCSLIB.ORG

Freshwater Silica-Scaled Heterotrophic Protista: Heliozoa, Thaumatomonad Flagellates, Amoebae, and Bicosoecids, from the Lake Itasca Region, Minnesota

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Freshwater Silica-Scaled Heterotrophic Protista: Heliozoa, Thaumatomonad Flagellates, Amoebae, and Bicosoecids, from the Lake Itasca Region, Minnesota JOURNAL OF THE MINNESOTA ACADEMY OF SCIENCE VOL. 78 NO. 2 (2015) FRESHWATER SILICA-SCALED HETEROTROPHIC PROTISTA: HELIOZOA, THAUMATOMONAD FLAGELLATES, AMOEBAE, AND BICOSOECIDS, FROM THE LAKE ITASCA REGION, MINNESOTA Daniel E. Wujek Central Michigan University, Mt. Pleasant, MI Forty-nine plankton samples were collected from the Lake Itasca Region, Minnesota over a period sporadically covering the summers of 1980, 1981 and 1987. A total of 22 freshwater heterotrophic siliceous-scaled species were observed: 18 heliozoa, two thaumatomonad flagellates, one bicosoecid, and one testate amoeba. Scale identifications were based on transmission electron microscopy. New records for North America include two heliozoans and one thaumatomonad flagellate. Five heliozoa taxa and one thaumatomonad flagellate are new records for the U.S. Wujek DE. Freshwater silica-scaled heterotrophic protista: heliozoa, thaumatomonad flagellates, amoebae, and bicosoecids, from the Lake Itasca Region, Minnesota. Minnesota Academy of Science Journal. 2015; 78(2):1-14. Keywords: bicosoecids, heliozoa, protista, testate amoeba, thaumatomonad flagellates Daniel E Wujek, Department of Biology, Central microscopy (EM) usually is necessary to distinguish Michigan University, Mt. Pleasant, MI 48859, e- sufficient morphology for species identification in the mail: [email protected]. scaled chrysophyte groups3 and now have become the This study was in part funded by a grant from the tool for other scaled protists. CMU FRCE committee. North American heterotrophic protist studies using INTRODUCTION electron microscopy in general have lagged behind The protist groups of golden brown algae those for Europe and Asia. The U.S. Great Lakes and (Chrysophyceae and Synurophyceae), heliozoa inland water’s heterotrophic freshwater protistan (Heliozoa, Filosea), thaumatomonads (Cercozoa, taxa, in particular the silica-scaled heliozoa and Thaumatomonadida), bicosoecids (Protozoa, scaled flagellates, are poorly documented using Bicosoecidida), and testate amoebae (Rhizopoda, electron microscopy (EM) with only a single species Himatismenida) are characterized by an exogenous being reported 4. On the contrary, more extensive siliceous or calcified envelope composed of scales Canadian studies by Nicholls and coworkers5-8 have and/or bristles or loricae. These organisms have long been reported. In contrast, the North American been recognized as important indicators of silica-scaled chrysophyte protist group environmental conditions. The silica-scaled (Chrysophyceae and Synurophyceae) have been chrysophytes are second in importance only after widely published3,9-15, including the Lake Itasca diatoms as indicators of the past ecology of lacustrine Region11-15. environments1,2. For example, the effects of acid rain were demonstrated by examining present and past Heliozoans are cosmopolitan, free-living aquatic sediments for scaled chrysophytes to demonstrate protozoans. Species are found in marine, brackish changes in the environment over time. and fresh waters. Some species have endosymbiotic algae, but most obtain their nutrition by phagocytosis, Identification of scale-bearing protists is based upon usually using characteristically long axopodia and the morphology of scales, which are often preserved short pseudopodia to capture their food. For recent in sediments1. Light microscopy-based reviews of the heliozoa see Febvre-Chevalier16, Lee identifications are of limited value, as electron et al.17, Page and Siemensma18 and Patterson and 1 JOURNAL OF THE MINNESOTA ACADEMY OF SCIENCE VOL. 78 NO. 2 (2015) Hedley19. An assessment of the centrohelid group Table 1. Lake Itasca Region sampling sites and and their worldwide distribution has been compiled dates containing heterotrophic silica-scaled by Mikrjukov20. protistans. Date In this study, the silica-scaled heterotrophic protists Sampling Site 1980 1981 1987 from samples collected during the summer months of Arco Lake x Beaver Pond, Hwy 4 x x 1977, 1980 and 1987 from 32 locations in the Lake Bohall Lake, north end x x Itasca Region, Minnesota, were observed using Bohall Pond, south end x transmission electron microscopy. All the sampling Chamber Creek x sites have a substantial and published silica-scaled Dahlberg Lake x phytoplankton record11-15. Darling Pond x x Deer Park Lake x MATERIALS AND METHODS Deming Pond, north x x x Forty-nine phytoplankton samples were collected Deming Pond, south x x x from 32 sampling sites with 20 µm mesh plankton Elk Creek x x x Hay Creek x x net from the Lake Itasca Region, Minnesota during Lasalle Creek x x the summer months of 1980, 1981 and 1987 (Table Lake Itasca, north arm x 1). Samples were preserved with acid Lugol’s in Lake Itasca, east arm x x plastic screw-cap vials. Samples for transmission Lake Itasca, west arm x x electron microscopy (TEM) were sub-sampled onto Long Lake x x Formvar-coated, carbon stabilized, 3 mm copper Mary Lake x Mississippi River culvert x x grids. After air drying, they were examined with Nicollet Lake x either a Philips EM300 or JEOL CM-10 TEM. All Pickerel Lake x identifications were based on TEM. The heliozoan Squaw Lake x 20 classification used is according to Mikrjukov . Twin Lake, east x Twin Lake, west x RESULTS Two Spot Trail, north x Twenty two heterotrophic freshwater silica-scaled pond #1 protists were observed during this investigation Two Spot Trail, north x (Table 2): 18 heliozoa taxa, two thaumatomonad pond #2 Two Spot Trail, south x flagellates, and one taxon each of a bicosoecid and pond #1 rhizopod amoeba (Plates 1-23). Of the eighteen Two Spot Trail, south x heliozoa observed, two are newly reported for North pond #2 America (Plates. 11, 19) and six for the U.S. (Plates. Upper Rice River x x 5, 7, 8, 15, 16, 17). The heliozoans observed all have Wild Rice River x x a cosmopolitan distribution20,21. Raphidocystis Wilderness Drive, south x tubifera was the most widely observed heliozoan in pond #1 Wilderness Drive, pond #2 x this study with the genus Acanthocystis having the greatest number of species (Table 2). Included in my using electron microscopy, Raineriophrys observations was the first heliozoan characterized erinaceoides (Plates 12-13), a species whose original description was as an Acanthocystis taxon from Denmark22. Thaumatomonad flagellates observed for the first time in North America was Gyromitus limax, and for the U.S., Thaumatomastix triangulata (Plate 21). All of taxa in the study are new records for Minnesota. 2 JOURNAL OF THE MINNESOTA ACADEMY OF SCIENCE VOL. 78 NO. 2 (2015) Table 2. Checklist of silica-scaled heliozoa, (Thomsen) Roijackers & Pickerel Lake thaumatomonad flagellates, amoeba, and Siemensma** bicosoecids from the Lake Itasca Region, Thaumatomonadida Minnesota, 1977, 1980, 1987. Thaumatomastix Dahlberg Lake Taxon Location triangulata (Balanov) Centrohelida Beech & Moestrup* Acanthocystis bicornis Deming Lake Gyromitus limax Belcher S. Deming Pond Dürrschmidt & Swale** Acanthocystis cornuta Nicolett Lake Himatismenida Dürrschmidt* Cochliopodium Hay Creek, Acanthocystis nichollsi Pickerel Lake bilimbosum Auerbach Pickerel Lake Siemensma & Roijackers Bicosoecida Acanthocystis penardi Hay Creek, Wild Cyathobodo crucifera Deming ponds Wailes* Rice River Swale & Belcher Acanthocystis polymorpha Deming Lake *New record for the United States Dürrschmidt* ponds, Wild **New record for North America (see Table 1 for Rice River dates) Acanthocystis turfacea Arco Lake Carter DISCUSSION Choanocystis aculeata Squaw Lake Heliozoa (Hertwig & Lesser) Siemensma & Roijackers Heliozoa are defines as predatory organisms, Pterocystis tropica Long Lake, Wild distinguished by their spherical body that is (Dürrschmidt) Rice River characterized with fine radiating cytoplasmic Siemensma** projections - the axopodia. These cytoplasmic Raineriophrys Hay Creek, E. projections participate in the capture of prey, erinaceoides (Petersen & Twin Lake, Two movement of cells, and adhesion to various Hansen) Mikrjukov Spot ponds, substrates. Long considered a natural taxonomic Wild Rice Lake group, recent molecular data indicate they are rather a Raphidiocystis tubifera Fish Hook Lake, polyphyletic assemblage of protists23,24. Penard Pickerel Lake, S. Deming Pond, Order Centroheliozoa (Centrohelids) Squaw Lake, Pickerel Lake Family Raphidiophryidae Raphidiophrys elegans E. Twin Lakes, Hertwig & Lesser Upper Rice Lake All taxa have external scales surrounded by a hollow Polyplacocystis marginata N. Deming Pond marginal rim. Spine scales, if present, are always (Siemensma) Mikrjukov symmetrical and either tubular, trumpet or funnel- Pompholyxophrys Dahlberg Lake, shaped. ovuligera Penard* Long Lake Pompholyxophrys punicea Wild Rice River Polyplacocystis marginata (Siemensma) Mikrjukov Archer* Figure 1, Plate 1. Pompholyxophrys stellata Deming Lake, Polyplacocystis marginata, originally described as Dürrschmidt and Hay Creek, 21 Nicholls* Pickerel Lake Raphidiophrys marginata Siemensma , it was later 25 Pinaciophora fluviatilis Lake Itasca, all transferred by Mikrjukov to his newly described Greeff arms genus Polyplacocystis. The genus contains five Rabdiophrys anulifera E. Twin Lake, species. Rainer emend. Siemensma Upper Rice Lake Rabdiophrys monopora Hay Creek, 3 JOURNAL OF THE MINNESOTA ACADEMY OF SCIENCE VOL. 78 NO. 2 (2015) Figure 1. Plates 1-12. Isolated surface scales. Plate 1. Polyplacocystis marginata, body scale. Plate 2. Raphidiophrys elegans, body scale. Plate 3. Raphidiocystis tubifera, plate scale. Plates 4-9. Acanthocystis. 4. A. bicornis,
Load more

Recommended publications
  • Protistology Mitochondrial Genomes of Amoebozoa
    Protistology 13 (4), 179–191 (2019) Protistology Mitochondrial genomes of Amoebozoa Natalya Bondarenko1, Alexey Smirnov1, Elena Nassonova1,2, Anna Glotova1,2 and Anna Maria Fiore-Donno3 1 Department of Invertebrate Zoology, Faculty of Biology, Saint Petersburg State University, 199034 Saint Petersburg, Russia 2 Laboratory of Cytology of Unicellular Organisms, Institute of Cytology RAS, 194064 Saint Petersburg, Russia 3 University of Cologne, Institute of Zoology, Terrestrial Ecology, 50674 Cologne, Germany | Submitted November 28, 2019 | Accepted December 10, 2019 | Summary In this mini-review, we summarize the current knowledge on mitochondrial genomes of Amoebozoa. Amoebozoa is a major, early-diverging lineage of eukaryotes, containing at least 2,400 species. At present, 32 mitochondrial genomes belonging to 18 amoebozoan species are publicly available. A dearth of information is particularly obvious for two major amoebozoan clades, Variosea and Tubulinea, with just one mitochondrial genome sequenced for each. The main focus of this review is to summarize features such as mitochondrial gene content, mitochondrial genome size variation, and presence or absence of RNA editing, showing if they are unique or shared among amoebozoan lineages. In addition, we underline the potential of mitochondrial genomes for multigene phylogenetic reconstruction in Amoebozoa, where the relationships among lineages are not fully resolved yet. With the increasing application of next-generation sequencing techniques and reliable protocols, we advocate mitochondrial
    [Show full text]
  • Rhizaria, Cercozoa)
    Protist, Vol. 166, 363–373, July 2015 http://www.elsevier.de/protis Published online date 28 May 2015 ORIGINAL PAPER Molecular Phylogeny of the Widely Distributed Marine Protists, Phaeodaria (Rhizaria, Cercozoa) a,1 a a b Yasuhide Nakamura , Ichiro Imai , Atsushi Yamaguchi , Akihiro Tuji , c d Fabrice Not , and Noritoshi Suzuki a Plankton Laboratory, Graduate School of Fisheries Sciences, Hokkaido University, Hakodate, Hokkaido 041–8611, Japan b Department of Botany, National Museum of Nature and Science, Tsukuba 305–0005, Japan c CNRS, UMR 7144 & Université Pierre et Marie Curie, Station Biologique de Roscoff, Equipe EPPO - Evolution du Plancton et PaléoOcéans, Place Georges Teissier, 29682 Roscoff, France d Institute of Geology and Paleontology, Graduate School of Science, Tohoku University, Sendai 980–8578, Japan Submitted January 1, 2015; Accepted May 19, 2015 Monitoring Editor: David Moreira Phaeodarians are a group of widely distributed marine cercozoans. These plankton organisms can exhibit a large biomass in the environment and are supposed to play an important role in marine ecosystems and in material cycles in the ocean. Accurate knowledge of phaeodarian classification is thus necessary to better understand marine biology, however, phylogenetic information on Phaeodaria is limited. The present study analyzed 18S rDNA sequences encompassing all existing phaeodarian orders, to clarify their phylogenetic relationships and improve their taxonomic classification. The mono- phyly of Phaeodaria was confirmed and strongly supported by phylogenetic analysis with a larger data set than in previous studies. The phaeodarian clade contained 11 subclades which generally did not correspond to the families and orders of the current classification system. Two families (Challengeri- idae and Aulosphaeridae) and two orders (Phaeogromida and Phaeocalpida) are possibly polyphyletic or paraphyletic, and consequently the classification needs to be revised at both the family and order levels by integrative taxonomy approaches.
    [Show full text]
  • Harmful Algae 91 (2020) 101587
    Harmful Algae 91 (2020) 101587 Contents lists available at ScienceDirect Harmful Algae journal homepage: www.elsevier.com/locate/hal Review Progress and promise of omics for predicting the impacts of climate change T on harmful algal blooms Gwenn M.M. Hennona,c,*, Sonya T. Dyhrmana,b,* a Lamont-Doherty Earth Observatory, Columbia University, Palisades, NY, United States b Department of Earth and Environmental Sciences, Columbia University, New York, NY, United States c College of Fisheries and Ocean Sciences University of Alaska Fairbanks Fairbanks, AK, United States ARTICLE INFO ABSTRACT Keywords: Climate change is predicted to increase the severity and prevalence of harmful algal blooms (HABs). In the past Genomics twenty years, omics techniques such as genomics, transcriptomics, proteomics and metabolomics have trans- Transcriptomics formed that data landscape of many fields including the study of HABs. Advances in technology have facilitated Proteomics the creation of many publicly available omics datasets that are complementary and shed new light on the Metabolomics mechanisms of HAB formation and toxin production. Genomics have been used to reveal differences in toxicity Climate change and nutritional requirements, while transcriptomics and proteomics have been used to explore HAB species Phytoplankton Harmful algae responses to environmental stressors, and metabolomics can reveal mechanisms of allelopathy and toxicity. In Cyanobacteria this review, we explore how omics data may be leveraged to improve predictions of how climate change will impact HAB dynamics. We also highlight important gaps in our knowledge of HAB prediction, which include swimming behaviors, microbial interactions and evolution that can be addressed by future studies with omics tools. Lastly, we discuss approaches to incorporate current omics datasets into predictive numerical models that may enhance HAB prediction in a changing world.
    [Show full text]
  • Differential Gene Expression Analysis and Cytological Evidence Reveal a Sexual Stage of an Amoeba with Multiparental Cellular and Nuclear Fusion
    PLOS ONE RESEARCH ARTICLE Differential gene expression analysis and cytological evidence reveal a sexual stage of an amoeba with multiparental cellular and nuclear fusion ☯ ☯ Yonas I. TekleID *, Fang Wang , Alireza Heidari, Alanna Johnson Stewart Department of Biology, Spelman College, Atlanta, Georgia, United States of America a1111111111 ☯ These authors contributed equally to this work. a1111111111 * [email protected] a1111111111 a1111111111 a1111111111 Abstract Sex is a hallmark of eukaryotes but its evolution in microbial eukaryotes is poorly elucidated. Recent genomic studies revealed microbial eukaryotes possess a genetic toolkit necessary OPEN ACCESS for sexual reproduction. However, the mechanism of sexual development in a majority of Citation: Tekle YI, Wang F, Heidari A, Stewart AJ microbial eukaryotes including amoebozoans is poorly characterized. The major hurdle in (2020) Differential gene expression analysis and studying sex in microbial eukaryotes is a lack of observational evidence, primarily due to its cytological evidence reveal a sexual stage of an cryptic nature. In this study, we used a tractable fusing amoeba, Cochliopodium, to investi- amoeba with multiparental cellular and nuclear fusion. PLoS ONE 15(11): e0235725. https://doi. gate sexual development using stage-specific Differential Gene Expression (DGE) and org/10.1371/journal.pone.0235725 cytological analyses. Both DGE and cytological results showed that most of the meiosis and Editor: Arthur J. Lustig, Tulane University Health sex-related genes are upregulated in Cochliopodium undergoing fusion in laboratory culture. Sciences Center, UNITED STATES Relative gene ontology (GO) category representations in unfused and fused cells revealed Received: June 19, 2020 a functional skew of the fused transcriptome toward DNA metabolism, nucleus and ligases that are suggestive of a commitment to sexual development.
    [Show full text]
  • A Persistent Giant Algal Virus, with a Unique Morphology, Encodes An
    bioRxiv preprint doi: https://doi.org/10.1101/2020.07.30.228163; this version posted January 13, 2021. The copyright holder for this preprint (which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made available under aCC-BY-NC-ND 4.0 International license. 1 A persistent giant algal virus, with a unique morphology, encodes an 2 unprecedented number of genes involved in energy metabolism 3 4 Romain Blanc-Mathieu1,2, Håkon Dahle3, Antje Hofgaard4, David Brandt5, Hiroki 5 Ban1, Jörn Kalinowski5, Hiroyuki Ogata1 and Ruth-Anne Sandaa6* 6 7 1: Institute for Chemical Research, Kyoto University, Gokasho, Uji, 611-0011, Japan 8 2: Laboratoire de Physiologie Cellulaire & Végétale, CEA, Univ. Grenoble Alpes, 9 CNRS, INRA, IRIG, Grenoble, France 10 3: Department of Biological Sciences and K.G. Jebsen Center for Deep Sea Research, 11 University of Bergen, Bergen, Norway 12 4: Department of Biosciences, University of Oslo, Norway 13 5: Center for Biotechnology, Universität Bielefeld, Bielefeld, 33615, Germany 14 6: Department of Biological Sciences, University of Bergen, Bergen, Norway 15 *Corresponding author: Ruth-Anne Sandaa, +47 55584646, [email protected] 1 bioRxiv preprint doi: https://doi.org/10.1101/2020.07.30.228163; this version posted January 13, 2021. The copyright holder for this preprint (which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made available under aCC-BY-NC-ND 4.0 International license. 16 Abstract 17 Viruses have long been viewed as entities possessing extremely limited metabolic 18 capacities.
    [Show full text]
  • A Revised Classification of Naked Lobose Amoebae (Amoebozoa
    Protist, Vol. 162, 545–570, October 2011 http://www.elsevier.de/protis Published online date 28 July 2011 PROTIST NEWS A Revised Classification of Naked Lobose Amoebae (Amoebozoa: Lobosa) Introduction together constitute the amoebozoan subphy- lum Lobosa, which never have cilia or flagella, Molecular evidence and an associated reevaluation whereas Variosea (as here revised) together with of morphology have recently considerably revised Mycetozoa and Archamoebea are now grouped our views on relationships among the higher-level as the subphylum Conosa, whose constituent groups of amoebae. First of all, establishing the lineages either have cilia or flagella or have lost phylum Amoebozoa grouped all lobose amoe- them secondarily (Cavalier-Smith 1998, 2009). boid protists, whether naked or testate, aerobic Figure 1 is a schematic tree showing amoebozoan or anaerobic, with the Mycetozoa and Archamoe- relationships deduced from both morphology and bea (Cavalier-Smith 1998), and separated them DNA sequences. from both the heterolobosean amoebae (Page and The first attempt to construct a congruent molec- Blanton 1985), now belonging in the phylum Per- ular and morphological system of Amoebozoa by colozoa - Cavalier-Smith and Nikolaev (2008), and Cavalier-Smith et al. (2004) was limited by the the filose amoebae that belong in other phyla lack of molecular data for many amoeboid taxa, (notably Cercozoa: Bass et al. 2009a; Howe et al. which were therefore classified solely on morpho- 2011). logical evidence. Smirnov et al. (2005) suggested The phylum Amoebozoa consists of naked and another system for naked lobose amoebae only; testate lobose amoebae (e.g. Amoeba, Vannella, this left taxa with no molecular data incertae sedis, Hartmannella, Acanthamoeba, Arcella, Difflugia), which limited its utility.
    [Show full text]
  • Review of the Center for Computational Sciences, University of Tsukuba 2020
    Review of the Center for Computational Sciences, University of Tsukuba 2020 筑波大学計算科学研究センター 外部評価報告書 September 2020 2020 年 9月 Center for Computational Sciences University of Tsukuba Review of the Center for Computational Sciences, University of Tsukuba 2014-2019 Foreword This volume contains the Report of the External Review for Center for Computational Scineces (CCS), University of Tsukuba, which was carried out in FY2019. The objective of the External Review was to evaluate the research activities of CCS during the period from FY2014 to FY2019 since the previous external review which was held in FY2013, and the future strategy and plans. Originally formed as the Center for Computational Physics (CCP) in 1992, the CCS was reorganized, expanded and relaunched under its current name in April 2004. The mission of the Center for Computational Sciences (CCS) is the promotion of "Multidisciplinary Computational Sciences" through enhanced cooperation between, and the fusion of, computational and computer sciences. The most important characteristics of the research collaboration in the CCS is “codesigning” where the needs from application fields and seeds from system technologies to make a balanced and optimized system development as well as application program development. As a unique research center where both computational and computer scientists work together, our codesigning for advanced High Performance Computing (HPC) research has been continued from the beginning until today. The CCS has developed several supercomputers, and conducted computational sciences in the areas of particle physics, astrophysics, nuclear physics, materials science, life science, environmental science, high performance computing technology, and information science including database technology and computational media. Also, the CCS plays a significant role as a nation-wide joint-use facility that provides computational resources for external scientific researchers in all of these areas all over the world.
    [Show full text]
  • Raphidiophrys Contractilis
    Kobe University Repository : Thesis Mechanism of β-1,3-glucan mediated food uptake in the protozoon 学位論文題目 Raphidiophrys contractilis(原生生物Raphidiophrys contractilis におけ Title るβ-1, 3-グルカンが介在する捕食機構) 氏名 MOUSUMI BHADRA Author 専攻分野 博士（理学） Degree 学位授与の日付 2017-09-25 Date of Degree 公開日 2018-09-25 Date of Publication 資源タイプ Thesis or Dissertation / 学位論文 Resource Type 報告番号 甲第7000号 Report Number 権利 Rights JaLCDOI URL http://www.lib.kobe-u.ac.jp/handle_kernel/D1007000 ※当コンテンツは神戸大学の学術成果です。無断複製・不正使用等を禁じます。著作権法で認められている範囲内で、適切にご利用ください。 PDF issue: 2021-10-07 Doctoral Dissertation Mechanism of β-1, 3-glucan mediated food uptake in the protozoon Raphidiophrys contractilis 原生生物 Raphidiophrys contractilis における β-1, 3-グルカンが介在する捕食機構 July 2017 Graduate School of Science Kobe University Mousumi Bhadra Contents Acknowledgements ............................................................................................................ 2 Summary ........................................................................................................................... 3 Chapter 1: Introductory review............................................................................................ 7 Chapter 2: Proteins required for food capturing in Raphidiophrys contractilis..................... 11 2.1. Introduction ....................................................................................................... 11 2.2. Materials and methods ........................................................................................ 15 2.3. Results ..............................................................................................................
    [Show full text]
  • Evidence for Glycolytic Reactions in the Mitochondrion?
    Broad Distribution of TPI-GAPDH Fusion Proteins among Eukaryotes: Evidence for Glycolytic Reactions in the Mitochondrion? Takuro Nakayama1, Ken-ichiro Ishida2, John M. Archibald1* 1 Department of Biochemistry & Molecular Biology, Canadian Institute for Advanced Research, Program in Integrated Microbial Biodiversity, Dalhousie University, Halifax, Nova Scotia, Canada, 2 Faculty of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Ibaraki, Japan Abstract Glycolysis is a central metabolic pathway in eukaryotic and prokaryotic cells. In eukaryotes, the textbook view is that glycolysis occurs in the cytosol. However, fusion proteins comprised of two glycolytic enzymes, triosephosphate isomerase (TPI) and glyceraldehyde-3-phosphate dehydrogenase (GAPDH), were found in members of the stramenopiles (diatoms and oomycetes) and shown to possess amino-terminal mitochondrial targeting signals. Here we show that mitochondrial TPI- GAPDH fusion protein genes are widely spread across the known diversity of stramenopiles, including non-photosynthetic species (Bicosoeca sp. and Blastocystis hominis). We also show that TPI-GAPDH fusion genes exist in three cercozoan taxa (Paulinella chromatophora, Thaumatomastix sp. and Mataza hastifera) and an apusozoan protist, Thecamonas trahens. Interestingly, subcellular localization predictions for other glycolytic enzymes in stramenopiles and a cercozoan show that a significant fraction of the glycolytic enzymes in these species have mitochondrial-targeted isoforms. These results suggest that part
    [Show full text]
  • Protist Phylogeny and the High-Level Classification of Protozoa
    Europ. J. Protistol. 39, 338–348 (2003) © Urban & Fischer Verlag http://www.urbanfischer.de/journals/ejp Protist phylogeny and the high-level classification of Protozoa Thomas Cavalier-Smith Department of Zoology, University of Oxford, South Parks Road, Oxford, OX1 3PS, UK; E-mail: [email protected] Received 1 September 2003; 29 September 2003. Accepted: 29 September 2003 Protist large-scale phylogeny is briefly reviewed and a revised higher classification of the kingdom Pro- tozoa into 11 phyla presented. Complementary gene fusions reveal a fundamental bifurcation among eu- karyotes between two major clades: the ancestrally uniciliate (often unicentriolar) unikonts and the an- cestrally biciliate bikonts, which undergo ciliary transformation by converting a younger anterior cilium into a dissimilar older posterior cilium. Unikonts comprise the ancestrally unikont protozoan phylum Amoebozoa and the opisthokonts (kingdom Animalia, phylum Choanozoa, their sisters or ancestors; and kingdom Fungi). They share a derived triple-gene fusion, absent from bikonts. Bikonts contrastingly share a derived gene fusion between dihydrofolate reductase and thymidylate synthase and include plants and all other protists, comprising the protozoan infrakingdoms Rhizaria [phyla Cercozoa and Re- taria (Radiozoa, Foraminifera)] and Excavata (phyla Loukozoa, Metamonada, Euglenozoa, Percolozoa), plus the kingdom Plantae [Viridaeplantae, Rhodophyta (sisters); Glaucophyta], the chromalveolate clade, and the protozoan phylum Apusozoa (Thecomonadea, Diphylleida). Chromalveolates comprise kingdom Chromista (Cryptista, Heterokonta, Haptophyta) and the protozoan infrakingdom Alveolata [phyla Cilio- phora and Miozoa (= Protalveolata, Dinozoa, Apicomplexa)], which diverged from a common ancestor that enslaved a red alga and evolved novel plastid protein-targeting machinery via the host rough ER and the enslaved algal plasma membrane (periplastid membrane).
    [Show full text]
  • Radiozoa (Acantharia, Phaeodaria and Radiolaria) and Heliozoa
    MICC16 26/09/2005 12:21 PM Page 188 CHAPTER 16 Radiozoa (Acantharia, Phaeodaria and Radiolaria) and Heliozoa Cavalier-Smith (1987) created the phylum Radiozoa to Radiating outwards from the central capsule are the include the marine zooplankton Acantharia, Phaeodaria pseudopodia, either as thread-like filopodia or as and Radiolaria, united by the presence of a central axopodia, which have a central rod of fibres for rigid- capsule. Only the Radiolaria including the siliceous ity. The ectoplasm typically contains a zone of frothy, Polycystina (which includes the orders Spumellaria gelatinous bubbles, collectively termed the calymma and Nassellaria) and the mixed silica–organic matter and a swarm of yellow symbiotic algae called zooxan- Phaeodaria are preserved in the fossil record. The thellae. The calymma in some spumellarian Radiolaria Acantharia have a skeleton of strontium sulphate can be so extensive as to obscure the skeleton. (i.e. celestine SrSO4). The radiolarians range from the A mineralized skeleton is usually present within the Cambrian and have a virtually global, geographical cell and comprises, in the simplest forms, either radial distribution and a depth range from the photic zone or tangential elements, or both. The radial elements down to the abyssal plains. Radiolarians are most useful consist of loose spicules, external spines or internal for biostratigraphy of Mesozoic and Cenozoic deep sea bars. They may be hollow or solid and serve mainly to sediments and as palaeo-oceanographical indicators. support the axopodia. The tangential elements, where Heliozoa are free-floating protists with roughly present, generally form a porous lattice shell of very spherical shells and thread-like pseudopodia that variable morphology, such as spheres, spindles and extend radially over a delicate silica endoskeleton.
    [Show full text]
  • Diversity and Evolution of Protist Mitochondria: Introns, Gene Content and Genome Architecture
    Diversity and Evolution of Protist Mitochondria: Introns, Gene Content and Genome Architecture 著者 西村 祐貴 内容記述 この博士論文は内容の要約のみの公開（または一部 非公開）になっています year 2016 その他のタイトル プロティストミトコンドリアの多様性と進化：イン トロン、遺伝子組成、ゲノム構造 学位授与大学 筑波大学 (University of Tsukuba) 学位授与年度 2015 報告番号 12102甲第7737号 URL http://hdl.handle.net/2241/00144261 Diversity and Evolution of Protist Mitochondria: Introns, Gene Content and Genome Architecture A Dissertation Submitted to the Graduate School of Life and Environmental Sciences, the University of Tsukuba in Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy in Science (Doctral Program in Biologial Sciences) Yuki NISHIMURA Table of Contents Abstract ........................................................................................................................... 1 Genes encoded in mitochondrial genomes of eukaryotes ..................................................... 3 Terminology .......................................................................................................................... 4 Chapter 1. General introduction ................................................................................ 5 The origin and evolution of mitochondria ............................................................................ 5 Mobile introns in mitochondrial genome .............................................................................. 6 The organisms which are lacking in mitochondrial genome data ........................................ 8 Chapter 2. Lateral transfers of mobile introns
    [Show full text]