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Trznadel M, Holt CC, Livingston SJ, Kwong WK, Keeling PJ. Coral-infecting parasites in cold marine ecosystems. Curr Biol 2024; 34:1810-1816.e4. [PMID: 38608678 DOI: 10.1016/j.cub.2024.03.026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2023] [Revised: 02/17/2024] [Accepted: 03/14/2024] [Indexed: 04/14/2024]
Abstract
Coral reefs are a biodiversity hotspot,1,2 and the association between coral and intracellular dinoflagellates is a model for endosymbiosis.3,4 Recently, corals and related anthozoans have also been found to harbor another kind of endosymbiont, apicomplexans called corallicolids.5 Apicomplexans are a diverse lineage of obligate intracellular parasites6 that include human pathogens such as the malaria parasite, Plasmodium.7 Global environmental sequencing shows corallicolids are tightly associated with tropical and subtropical reef environments,5,8,9 where they infect diverse corals across a range of depths in many reef systems, and correlate with host mortality during bleaching events.10 All of this points to corallicolids being ecologically significant to coral reefs, but it is also possible they are even more widely distributed because most environmental sampling is biased against parasites that maintain a tight association with their hosts throughout their life cycle. We tested the global distribution of corallicolids using a more direct approach, by specifically targeting potential anthozoan host animals from cold/temperate marine waters outside the coral reef context. We found that corallicolids are in fact common in such hosts, in some cases at high frequency, and that they infect the same tissue as parasites from topical coral reefs. Parasite phylogeny suggests corallicolids move between hosts and habitats relatively frequently, but that biogeography is more conserved. Overall, these results greatly expand the range of corallicolids beyond coral reefs, suggesting they are globally distributed parasites of marine anthozoans, which also illustrates significant blind spots that result from strategies commonly used to sample microbial biodiversity.
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Affiliation(s)
- Morelia Trznadel
- Botany Department, University of British Columbia, 6270 University Boulevard, Vancouver, BC V6T 1Z4, Canada
| | - Corey C Holt
- Botany Department, University of British Columbia, 6270 University Boulevard, Vancouver, BC V6T 1Z4, Canada
| | - Samuel J Livingston
- Botany Department, University of British Columbia, 6270 University Boulevard, Vancouver, BC V6T 1Z4, Canada
| | - Waldan K Kwong
- Botany Department, University of British Columbia, 6270 University Boulevard, Vancouver, BC V6T 1Z4, Canada
| | - Patrick J Keeling
- Botany Department, University of British Columbia, 6270 University Boulevard, Vancouver, BC V6T 1Z4, Canada.
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2
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Tuzlak L, Alves-Ferreira EV, Kennard A, Shehata C, Schwartz CL, Grigg ME. Ultrastructural identification and molecular characterization of two new parabasalid species that naturally colonize laboratory mice, Tritrichomonas musculus and Tritrichomonas casperi. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.01.20.524969. [PMID: 36789430 PMCID: PMC9928039 DOI: 10.1101/2023.01.20.524969] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
Tritrichomonas muris is a flagellated protist isolated from the cecum of wild mice in the Czech Republic. This commensal protist has been shown previously to alter immune phenotypes in laboratory mice. Other trichomonads, previously referred to as Tritrichomonas musculis and Tritrichomonas rainier , also naturally colonize laboratory mice and cause immune alterations. This report formally describes two new trichomonads, Tritrichomonas musculus n. sp., and Tritrichomonas casperi n. sp., at the ultrastructural and molecular level. These two protists were isolated from laboratory mice, and were differentiated by their size and the structure of their undulating membrane and posterior flagellum. Analysis at the 18S rRNA and trans- ITS genetic loci supported their designation as distinct species, related to T. muris . To further assess the true extent of parabasalid diversity infecting laboratory mice, 135 mice were screened at the NIH using pan-parabasalid primers that amplify the trans- ITS region. Forty-four percent of mice were positive for parabasalids, encompassing a total of 8 distinct sequence types. Tritrichomonas casperi and Trichomitus- like protists were dominant. T. musculus and T. rainier were also detected, but T. muris was not. Our work establishes a previously underappreciated diversity of commensal trichomonad protists that naturally colonize the enteric cavity of laboratory mice.
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Affiliation(s)
- Leila Tuzlak
- Molecular Parasitology Section, Laboratory of Parasitic Diseases, National Institutes of Health, National Institute of Allergy and Infectious Diseases (NIAID), Bethesda, Maryland, 20892, USA
| | - Eliza V.C. Alves-Ferreira
- Molecular Parasitology Section, Laboratory of Parasitic Diseases, National Institutes of Health, National Institute of Allergy and Infectious Diseases (NIAID), Bethesda, Maryland, 20892, USA
| | - Andrea Kennard
- Molecular Parasitology Section, Laboratory of Parasitic Diseases, National Institutes of Health, National Institute of Allergy and Infectious Diseases (NIAID), Bethesda, Maryland, 20892, USA
| | - Christina Shehata
- Molecular Parasitology Section, Laboratory of Parasitic Diseases, National Institutes of Health, National Institute of Allergy and Infectious Diseases (NIAID), Bethesda, Maryland, 20892, USA
| | - Cindi L. Schwartz
- Electron Microscopy Unit, Research Technologies Branch, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, Hamilton, Montana, 59840, USA
| | - Michael E. Grigg
- Molecular Parasitology Section, Laboratory of Parasitic Diseases, National Institutes of Health, National Institute of Allergy and Infectious Diseases (NIAID), Bethesda, Maryland, 20892, USA
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3
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Centrohelid heliozoans of Ukraine with a description of a new genus and species (Haptista: Centroplasthelida). Eur J Protistol 2022; 86:125916. [DOI: 10.1016/j.ejop.2022.125916] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2022] [Revised: 08/04/2022] [Accepted: 08/22/2022] [Indexed: 11/15/2022]
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4
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Tikhonenkov DV, Jamy M, Borodina AS, Belyaev AO, Zagumyonnyi DG, Prokina KI, Mylnikov AP, Burki F, Karpov SA. On the origin of TSAR: morphology, diversity and phylogeny of Telonemia. Open Biol 2022; 12:210325. [PMID: 35291881 PMCID: PMC8924772 DOI: 10.1098/rsob.210325] [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] [Indexed: 01/09/2023] Open
Abstract
Telonemia is a poorly known major phylum of flagellated eukaryotes with a unique combination of morphological traits. Phylogenomics recently revealed the phylogenetic position of telonemids as sister to SAR, one of the largest groups of eukaryotes, comprising Stramenopiles, Alveolata and Rhizaria. Due to this key evolutionary position, investigations of telonemids are of critical importance for elucidating the origin and diversification of an astounding diversity of eukaryotic forms and life strategies. To date, however, only two species have been morphologically characterized from Telonemia, which do not represent this genetically very diverse group. In this study, we established cultures for six new telonemid strains, including the description of five new species and a new genus. We used these cultures to update the phylogeny of Telonemia and provide a detailed morphological and ultrastructural investigation. Our data elucidate the origin of TSAR from flagellates with complex morphology and reconstruction of the ancestral structure of stramenopiles, alveolates and rhizarians, and their main synapomorphic characters. Since telonemids are a common component of aquatic environments, the features of their feeding, behaviour and ecological preferences observed in clonal cultures and the results of global metabarcoding analysis contribute to a deeper understanding of organization of microbial food webs.
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Affiliation(s)
- Denis V. Tikhonenkov
- Papanin Institute for Biology of Inland Waters, Russian Academy of Sciences, Borok, Russia
| | - Mahwash Jamy
- Department of Organismal Biology, Program in Systematic Biology, Uppsala University, Uppsala, Sweden
| | - Anastasia S. Borodina
- Papanin Institute for Biology of Inland Waters, Russian Academy of Sciences, Borok, Russia,Department of Zoology and Parasitology, Voronezh State University, Voronezh, Russia
| | - Artem O. Belyaev
- Papanin Institute for Biology of Inland Waters, Russian Academy of Sciences, Borok, Russia,Department of Zoology and Ecology, Penza State University, Penza, Russia
| | - Dmitry G. Zagumyonnyi
- Papanin Institute for Biology of Inland Waters, Russian Academy of Sciences, Borok, Russia
| | - Kristina I. Prokina
- Papanin Institute for Biology of Inland Waters, Russian Academy of Sciences, Borok, Russia,Ecologie Systématique Evolution, CNRS, Université Paris-Saclay, AgroParisTech, Orsay, France
| | - Alexander P. Mylnikov
- Papanin Institute for Biology of Inland Waters, Russian Academy of Sciences, Borok, Russia
| | - Fabien Burki
- Department of Organismal Biology, Program in Systematic Biology, Uppsala University, Uppsala, Sweden,Science for Life Laboratory, Uppsala University, Uppsala, Sweden
| | - Sergey A. Karpov
- Zoological Institute, Russian Academy of Sciences, Saint Petersburg, Russia,Department of Invertebrate Zoology, Faculty of Biology, Saint Petersburg State University, Saint Petersburg, Russia
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5
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Cho A, Tikhonenkov DV, Hehenberger E, Karnkowska A, Mylnikov AP, Keeling PJ. Monophyly of Diverse Bigyromonadea and their Impact on Phylogenomic Relationships Within Stramenopiles. Mol Phylogenet Evol 2022; 171:107468. [DOI: 10.1016/j.ympev.2022.107468] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2021] [Revised: 02/11/2022] [Accepted: 02/22/2022] [Indexed: 10/18/2022]
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6
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Zlatogursky VV, Shɨshkin Y, Drachko D, Burki F. The long-time orphan protist Meringosphaera mediterranea Lohmann, 1902 [1903] is a centrohelid heliozoan. J Eukaryot Microbiol 2021; 68:e12860. [PMID: 34048133 DOI: 10.1111/jeu.12860] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Meringosphaera is an enigmatic marine protist without clear phylogenetic affiliation, but it has long been suggested to be a chrysophyte-related autotroph. Microscopy-based reports indicate that it has a worldwide distribution, but no sequence data exist so far. We obtained the first 18S rDNA sequence for M. mediterranea (identified using light and electron microscopy) from the west coast of Sweden. Observations of living cells revealed granulated axopodia and up to 6 globular photosynthesizing bodies about 2 μm in diameter, the nature of which requires further investigation. The ultrastructure of barbed undulating spine scales and patternless plate scales with a central thickening is in agreement with previous reports. Molecular phylogenetic analysis placed M. mediterranea inside the NC5 environmental clade of Centroplasthelida (Haptista) along with additional environmental sequences, together closely related to Choanocystidae. This placement is supported by similar scales in Meringosphaera and Choanocystidae. We searched the Tara Oceans 18S V9 metabarcoding dataset, which revealed four OTUs with 94.8%-98.2% similarity, with oceanic distribution similar to that based on morphological observations. The current taxonomic position and species composition of the genus are discussed. The planktonic lifestyle of M. mediterranea contradicts the view of some authors that centrohelids enter the plankton only temporarily.
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Affiliation(s)
- Vasily V Zlatogursky
- Department of Invertebrate Zoology, Faculty of Biology, St. Petersburg State University, St. Petersburg, Russia.,Department of Organismal Biology, Systematic Biology Program, Uppsala University, Uppsala, Sweden
| | - Yegor Shɨshkin
- Department of Invertebrate Zoology, Faculty of Biology, St. Petersburg State University, St. Petersburg, Russia
| | - Daria Drachko
- Department of Invertebrate Zoology, Faculty of Biology, St. Petersburg State University, St. Petersburg, Russia.,Laboratory of Cellular and Molecular Protistology, Zoological Institute RAS, St. Petersburg, Russia
| | - Fabien Burki
- Department of Organismal Biology, Systematic Biology Program, Uppsala University, Uppsala, Sweden.,Science for Life Laboratory, Uppsala University, Uppsala, Sweden
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7
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Characterization of new cristamonad species from kalotermitid termites including a novel genus, Runanympha. Sci Rep 2021; 11:7270. [PMID: 33790354 PMCID: PMC8012604 DOI: 10.1038/s41598-021-86645-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2020] [Accepted: 03/16/2021] [Indexed: 12/04/2022] Open
Abstract
Cristamonadea is a large class of parabasalian protists that reside in the hindguts of wood-feeding insects, where they play an essential role in the digestion of lignocellulose. This group of symbionts boasts an impressive array of complex morphological characteristics, many of which have evolved multiple times independently. However, their diversity is understudied and molecular data remain scarce. Here we describe seven new species of cristamonad symbionts from Comatermes, Calcaritermes, and Rugitermes termites from Peru and Ecuador. To classify these new species, we examined cells by light and scanning electron microscopy, sequenced the symbiont small subunit ribosomal RNA (rRNA) genes, and carried out barcoding of the mitochondrial large subunit rRNA gene of the hosts to confirm host identification. Based on these data, five of the symbionts characterized here represent new species within described genera: Devescovina sapara n. sp., Devescovina aymara n. sp., Macrotrichomonas ashaninka n. sp., Macrotrichomonas secoya n. sp., and Macrotrichomonas yanesha n. sp. Additionally, two symbionts with overall morphological characteristics similar to the poorly-studied and probably polyphyletic ‘joeniid’ Parabasalia are classified in a new genus Runanympha n. gen.: Runanympha illapa n. sp., and Runanympha pacha n. sp.
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8
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Predatory colponemids are the sister group to all other alveolates. Mol Phylogenet Evol 2020; 149:106839. [PMID: 32325195 DOI: 10.1016/j.ympev.2020.106839] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2020] [Revised: 04/03/2020] [Accepted: 04/09/2020] [Indexed: 11/20/2022]
Abstract
Alveolates are a major supergroup of eukaryotes encompassing more than ten thousand free-living and parasitic species, including medically, ecologically, and economically important apicomplexans, dinoflagellates, and ciliates. These three groups are among the most widespread eukaryotes on Earth, and their environmental success can be linked to unique innovations that emerged early in each group. Understanding the emergence of these well-studied and diverse groups and their innovations has relied heavily on the discovery and characterization of early-branching relatives, which allow ancestral states to be inferred with much greater confidence. Here we report the phylogenomic analyses of 313 eukaryote protein-coding genes from transcriptomes of three members of one such group, the colponemids (Colponemidia), which support their monophyly and position as the sister lineage to all other known alveolates. Colponemid-related sequences from environmental surveys and our microscopical observations show that colponemids are not common in nature, but they are diverse and widespread in freshwater habitats around the world. Studied colponemids possess two types of extrusive organelles (trichocysts or toxicysts) for active hunting of other unicellular eukaryotes and potentially play an important role in microbial food webs. Colponemids have generally plesiomorphic morphology and illustrate the ancestral state of Alveolata. We further discuss their importance in understanding the evolution of alveolates and the origin of myzocytosis and plastids.
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9
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Tikhonenkov DV, Jhin SH, Eglit Y, Miller K, Plotnikov A, Simpson AGB, Park JS. Ecological and evolutionary patterns in the enigmatic protist genus Percolomonas (Heterolobosea; Discoba) from diverse habitats. PLoS One 2019; 14:e0216188. [PMID: 31465455 PMCID: PMC6715209 DOI: 10.1371/journal.pone.0216188] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2019] [Accepted: 08/14/2019] [Indexed: 12/26/2022] Open
Abstract
The heterotrophic flagellate Percolomonas cosmopolitus (Heterolobosea) is often observed in saline habitats worldwide, from coastal waters to saturated brines. However, only two cultures assigned to this morphospecies have been examined using molecular methods, and their 18S rRNA gene sequences are extremely different. Further the salinity tolerances of individual strains are unknown. Thus, our knowledge on the autecology and diversity in this morphospecies is deficient. Here, we report 18S rRNA gene data on seven strains similar to P. cosmopolitus from seven geographically remote locations (New Zealand, Kenya, Korea, Poland, Russia, Spain, and the USA) with sample salinities ranging from 4‰ to 280‰, and compare morphology and salinity tolerance of the nine available strains. Percolomonas cosmopolitus-like strains show few-to-no consistent morphological differences, and form six clades separated by often extremely large 18S rRNA gene divergences (up to 42.4%). Some strains grow best at salinities from 75 to 125‰ and represent halophiles. All but one of these belong to two geographically heterogeneous clusters that form a robust monophyletic group in phylogenetic trees; this likely represents an ecologically specialized subclade of halophiles. Our results suggest that P. cosmopolitus is a cluster of several cryptic species (at least), which are unlikely to be distinguished by geography. Interestingly, the 9 Percolomonas strains formed a clade in 18S rRNA gene phylogenies, unlike most previous analyses based on two sequences.
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Affiliation(s)
- Denis V. Tikhonenkov
- Papanin Institute for Biology of Inland Waters, Russian Academy of Sciences, Borok, Russia
- Zoological Institute, Russian Academy of Sciences, Saint Petersburg, Russia
| | - Soo Hwan Jhin
- Department of Oceanography, Research Institute for Dok-do and Ulleung-do Island and Kyungpook Institute of Oceanography, School of Earth System Sciences, Kyungpook National University, Daegu, Korea
| | - Yana Eglit
- Department of Biology, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Kai Miller
- Department of Biology, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Andrey Plotnikov
- Center of Shared Scientific Equipment “Persistence of Microorganisms”, Institute for Cellular and Intracellular Symbiosis UB RAS, Orenburg, Russia
| | - Alastair G. B. Simpson
- Department of Biology, Dalhousie University, Halifax, Nova Scotia, Canada
- Canadian Institute for Advanced Research, Program in Integrated Microbial Diversity, Toronto, Ontario, Canada
| | - Jong Soo Park
- Department of Oceanography, Research Institute for Dok-do and Ulleung-do Island and Kyungpook Institute of Oceanography, School of Earth System Sciences, Kyungpook National University, Daegu, Korea
- * E-mail:
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10
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Taerum SJ, Jasso‐Selles DE, Wilson M, Ware JL, Sillam‐Dussès D, Šobotník J, Gile GH. Molecular Identity of
Holomastigotes
(Spirotrichonymphea, Parabasalia) with Descriptions of
Holomastigotes flavipes
n. sp. and
Holomastigotes tibialis
n. sp. J Eukaryot Microbiol 2019; 66:882-891. [DOI: 10.1111/jeu.12739] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2018] [Revised: 03/22/2019] [Accepted: 04/18/2019] [Indexed: 11/27/2022]
Affiliation(s)
- Stephen J. Taerum
- School of Life Sciences Arizona State University 427 E Tyler Mall 85287 Tempe Arizona
| | | | - Megan Wilson
- Department of Biological Sciences Rutgers‐Newark University Boyden Hall, 195 University Ave 07102 Newark New Jersey
| | - Jessica L. Ware
- Department of Biological Sciences Rutgers‐Newark University Boyden Hall, 195 University Ave 07102 Newark New Jersey
| | - David Sillam‐Dussès
- Laboratory of Experimental and Comparative Ethology (LEEC) University of Paris 13 Sorbonne Paris Cité, 99 avenue Jean‐Baptiste Clément 93430 Villetaneuse France
| | - Jan Šobotník
- Faculty of Forestry and Wood Sciences Czech University of Life Sciences Kamýcká 129 165 21 Prague 6 Czech Republic
| | - Gillian H. Gile
- School of Life Sciences Arizona State University 427 E Tyler Mall 85287 Tempe Arizona
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11
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Irwin NA, Tikhonenkov DV, Hehenberger E, Mylnikov AP, Burki F, Keeling PJ. Phylogenomics supports the monophyly of the Cercozoa. Mol Phylogenet Evol 2019; 130:416-423. [DOI: 10.1016/j.ympev.2018.09.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2018] [Accepted: 09/06/2018] [Indexed: 01/09/2023]
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12
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Taerum SJ, De Martini F, Liebig J, Gile GH. Incomplete Co-cladogenesis Between Zootermopsis Termites and Their Associated Protists. ENVIRONMENTAL ENTOMOLOGY 2018; 47:184-195. [PMID: 29325010 DOI: 10.1093/ee/nvx193] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2017] [Indexed: 06/07/2023]
Abstract
Coevolution is a major driver of speciation in many host-associated symbionts. In the termite-protist digestive symbiosis, the protists are vertically inherited by anal feeding among nest mates. Lower termites (all termite families except Termitidae) and their symbionts have broadly co-diversified over ~170 million yr. However, this inference is based mainly on the restricted distribution of certain protist genera to certain termite families. With the exception of one study, which demonstrated congruent phylogenies for the protist Pseudotrichonympha and its Rhinotermitidae hosts, coevolution in this symbiosis has not been investigated with molecular methods. Here we have characterized the hindgut symbiotic protists (Phylum Parabasalia) across the genus Zootermopsis (Archotermopsidae) using single cell isolation, molecular phylogenetics, and high-throughput amplicon sequencing. We report that the deepest divergence in the Zootermopsis phylogeny (Zootermopsis laticeps [Banks; Isoptera: Termopsidae]) corresponds with a divergence in three of the hindgut protist species. However, the crown Zootermopsis taxa (Zootermopsis angusticollis [Hagen; Isoptera: Termopsidae], Z. nevadensis nevadensis [Hagen; Isoptera: Termopsidae], and Z. nevadensis nuttingi [Haverty & Thorne; Isoptera: Termopsidae]) share the same protist species, with no evidence of co-speciation under our methods. We interpret this pattern as incomplete co-cladogenesis, though the possibility of symbiont exchange cannot be entirely ruled out. This is the first molecular evidence that identical communities of termite-associated protist species can inhabit multiple distinct host species.
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Affiliation(s)
| | | | - Jürgen Liebig
- School of Life Sciences, Arizona State University, Tempe, AZ
| | - Gillian H Gile
- School of Life Sciences, Arizona State University, Tempe, AZ
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13
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Nalepa CA. What Kills the Hindgut Flagellates of Lower Termites during the Host Molting Cycle? Microorganisms 2017; 5:E82. [PMID: 29258251 PMCID: PMC5748591 DOI: 10.3390/microorganisms5040082] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2017] [Revised: 12/07/2017] [Accepted: 12/09/2017] [Indexed: 11/17/2022] Open
Abstract
Subsocial wood feeding cockroaches in the genus Cryptocercus, the sister group of termites, retain their symbiotic gut flagellates during the host molting cycle, but in lower termites, closely related flagellates die prior to host ecdysis. Although the prevalent view is that termite flagellates die because of conditions of starvation and desiccation in the gut during the host molting cycle, the work of L.R. Cleveland in the 1930s through the 1960s provides a strong alternate hypothesis: it was the changed hormonal environment associated with the origin of eusociality and its concomitant shift in termite developmental ontogeny that instigates the death of the flagellates in termites. Although the research on termite gut microbial communities has exploded since the advent of modern molecular techniques, the role of the host hormonal environment on the life cycle of its gut flagellates has been neglected. Here Cleveland's studies are revisited to provide a basis for re-examination of the problem, and the results framed in the context of two alternate hypotheses: the flagellate symbionts are victims of the change in host social status, or the flagellates have become incorporated into the life cycle of the eusocial termite colony. Recent work on parasitic protists suggests clear paths for exploring these hypotheses and for resolving long standing issues regarding sexual-encystment cycles in flagellates of the Cryptocercus-termite lineage using molecular methodologies, bringing the problem into the modern era.
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Affiliation(s)
- Christine A Nalepa
- Department of Entomology, North Carolina State University, Raleigh, NC 27695-7613, USA.
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14
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The parabasalid symbiont community of Heterotermes aureus: Molecular and morphological characterization of four new species and reestablishment of the genus Cononympha. Eur J Protistol 2017; 61:48-63. [DOI: 10.1016/j.ejop.2017.09.001] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2017] [Revised: 08/22/2017] [Accepted: 09/01/2017] [Indexed: 11/19/2022]
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15
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Nguyen NH, Suh SO, Blackwell M. Five novelCandidaspecies in insect-associated yeast clades isolated fromNeuropteraand other insects. Mycologia 2017. [DOI: 10.1080/15572536.2007.11832516] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Affiliation(s)
| | | | - Meredith Blackwell
- Department of Biological Sciences, Louisiana State University, Baton Rouge, Louisiana 70803
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16
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James ER, Okamoto N, Burki F, Scheffrahn RH, Keeling PJ. Cthulhu Macrofasciculumque n. g., n. sp. and Cthylla Microfasciculumque n. g., n. sp., a newly identified lineage of parabasalian termite symbionts. PLoS One 2013; 8:e58509. [PMID: 23526991 PMCID: PMC3601090 DOI: 10.1371/journal.pone.0058509] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2012] [Accepted: 02/05/2013] [Indexed: 11/18/2022] Open
Abstract
The parabasalian symbionts of lower termite hindgut communities are well-known for their large size and structural complexity. The most complex forms evolved multiple times independently from smaller and simpler flagellates, but we know little of the diversity of these small flagellates or their phylogenetic relationships to more complex lineages. To understand the true diversity of Parabasalia and how their unique cellular complexity arose, more data from smaller and simpler flagellates are needed. Here, we describe two new genera of small-to-intermediate size and complexity, represented by the type species Cthulhu macrofasciculumque and Cthylla microfasciculumque from Prorhinotermes simplex and Reticulitermes virginicus, respectively (both hosts confirmed by DNA barcoding). Both genera have a single anterior nucleus embeded in a robust protruding axostyle, and an anterior bundle flagella (and likely a single posterior flagellum) that emerge slightly subanteriorly and have a distinctive beat pattern. Cthulhu is relatively large and has a distinctive bundle of over 20 flagella whereas Cthylla is smaller, has only 5 anterior flagella and closely resembles several other parababsalian genera. Molecular phylogenies based on small subunit ribosomal RNA (SSU rRNA) show both genera are related to previously unidentified environmental sequences from other termites (possibly from members of the Tricercomitidae), which all branch as sisters to the Hexamastigitae. Altogether, Cthulhu likely represents another independent origin of relatively high cellular complexity within parabasalia, and points to the need for molecular characterization of other key taxa, such as Tricercomitus.
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Affiliation(s)
- Erick R. James
- Department of Botany, Canadian Institute for Advanced Research, University of British Columbia, Vancouver, British Columbia, Canada
| | - Noriko Okamoto
- Department of Botany, Canadian Institute for Advanced Research, University of British Columbia, Vancouver, British Columbia, Canada
| | - Fabien Burki
- Department of Botany, Canadian Institute for Advanced Research, University of British Columbia, Vancouver, British Columbia, Canada
| | - Rudolf H. Scheffrahn
- University of Florida Research and Education Center, Davie, Florida, United States of America
| | - Patrick J. Keeling
- Department of Botany, Canadian Institute for Advanced Research, University of British Columbia, Vancouver, British Columbia, Canada
- * E-mail:
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17
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Single-Cell DNA barcoding using sequences from the small subunit rRNA and internal transcribed spacer region identifies new species of Trichonympha and Trichomitopsis from the hindgut of the termite Zootermopsis angusticollis. PLoS One 2013; 8:e58728. [PMID: 23536818 PMCID: PMC3594152 DOI: 10.1371/journal.pone.0058728] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2012] [Accepted: 02/05/2013] [Indexed: 11/19/2022] Open
Abstract
To aid in their digestion of wood, lower termites are known to harbour a diverse community of prokaryotes as well as parabasalid and oxymonad protist symbionts. One of the best-studied lower termite gut communities is that of Zootermopsis angusticollis which has been known for almost 100 years to possess 3 species of Trichonympha (T. campanula, T. collaris, and T. sphaerica), 1 species of Trichomitopsis (T. termopsidis), as well as smaller flagellates. We have re-assessed this community by sequencing the small subunit (SSU) rRNA gene and the internal transcribed spacer (ITS) region from a large number of single Trichonympha and Trichomitopsis cells for which morphology was also documented. Based on phylogenetic clustering and sequence divergence, we identify 3 new species: Trichonympha postcylindrica, Trichomitopsis minor, and Trichomitopsis parvus spp. nov. Once identified by sequencing, the morphology of the isolated cells for all 3 new species was re-examined and found to be distinct from the previously described species: Trichonympha postcylindrica can be morphologically distinguished from the other Trichonympha species by an extension on its posterior end, whereas Trichomitopsis minor and T. parvus are smaller than T. termopsidis but similar in size to each other and cannot be distinguished based on morphology using light microscopy. Given that Z. angusticollis has one of the best characterized hindgut communities, the near doubling of the number of the largest and most easily identifiable symbiont species suggests that the diversity of hindgut symbionts is substantially underestimated in other termites as well. Accurate descriptions of the diversity of these microbial communities are essential for understanding hindgut ecology and disentangling the interactions among the symbionts, and molecular barcoding should be a priority for these systems.
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18
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Noda S, Mantini C, Meloni D, Inoue JI, Kitade O, Viscogliosi E, Ohkuma M. Molecular phylogeny and evolution of parabasalia with improved taxon sampling and new protein markers of actin and elongation factor-1α. PLoS One 2012; 7:e29938. [PMID: 22253832 PMCID: PMC3253790 DOI: 10.1371/journal.pone.0029938] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2011] [Accepted: 12/08/2011] [Indexed: 11/27/2022] Open
Abstract
Background Inferring the evolutionary history of phylogenetically isolated, deep-branching groups of taxa—in particular determining the root—is often extraordinarily difficult because their close relatives are unavailable as suitable outgroups. One of these taxonomic groups is the phylum Parabasalia, which comprises morphologically diverse species of flagellated protists of ecological, medical, and evolutionary significance. Indeed, previous molecular phylogenetic analyses of members of this phylum have yielded conflicting and possibly erroneous inferences. Furthermore, many species of Parabasalia are symbionts in the gut of termites and cockroaches or parasites and therefore formidably difficult to cultivate, rendering available data insufficient. Increasing the numbers of examined taxa and informative characters (e.g., genes) is likely to produce more reliable inferences. Principal Findings Actin and elongation factor-1α genes were identified newly from 22 species of termite-gut symbionts through careful manipulations and seven cultured species, which covered major lineages of Parabasalia. Their protein sequences were concatenated and analyzed with sequences of previously and newly identified glyceraldehyde-3-phosphate dehydrogenase and the small-subunit rRNA gene. This concatenated dataset provided more robust phylogenetic relationships among major groups of Parabasalia and a more plausible new root position than those previously reported. Conclusions/Significance We conclude that increasing the number of sampled taxa as well as the addition of new sequences greatly improves the accuracy and robustness of the phylogenetic inference. A morphologically simple cell is likely the ancient form in Parabasalia as opposed to a cell with elaborate flagellar and cytoskeletal structures, which was defined as most basal in previous inferences. Nevertheless, the evolution of Parabasalia is complex owing to several independent multiplication and simplification events in these structures. Therefore, systematics based solely on morphology does not reflect the evolutionary history of parabasalids.
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Affiliation(s)
- Satoko Noda
- Microbe Division/Japan Collection of Microorganisms, RIKEN BioResource Center, Wako, Saitama, Japan
- Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi, Kofu, Yamanashi, Japan
- * E-mail: (SN); (MO)
| | - Cléa Mantini
- Center for Infection and Immunity of Lille, Institut Pasteur de Lille, Lille, France, and Inserm U1019, CNRS UMR 8204, and University Lille – Nord de France, Lille, France
| | - Dionigia Meloni
- Center for Infection and Immunity of Lille, Institut Pasteur de Lille, Lille, France, and Inserm U1019, CNRS UMR 8204, and University Lille – Nord de France, Lille, France
- Department of Biomedical Sciences, Division of Experimental and Clinical Microbiology, University of Sassari, Sassari, Italy
| | - Jun-Ichi Inoue
- Microbe Division/Japan Collection of Microorganisms, RIKEN BioResource Center, Wako, Saitama, Japan
| | - Osamu Kitade
- Natural History Laboratory, College of Science, Ibaraki University, Mito, Ibaraki, Japan
| | - Eric Viscogliosi
- Center for Infection and Immunity of Lille, Institut Pasteur de Lille, Lille, France, and Inserm U1019, CNRS UMR 8204, and University Lille – Nord de France, Lille, France
| | - Moriya Ohkuma
- Microbe Division/Japan Collection of Microorganisms, RIKEN BioResource Center, Wako, Saitama, Japan
- * E-mail: (SN); (MO)
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19
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Gile GH, James ER, Scheffrahn RH, Carpenter KJ, Harper JT, Keeling PJ. Molecular and morphological analysis of the family Calonymphidae with a description of Calonympha chia sp. nov., Snyderella kirbyi sp. nov., Snyderella swezyae sp. nov. and Snyderella yamini sp. nov. Int J Syst Evol Microbiol 2011; 61:2547-2558. [DOI: 10.1099/ijs.0.028480-0] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Calonymphids are a group of multinucleate, multiflagellate protists belonging to the order Cristamonadida (Parabasalia) that are found exclusively in the hindgut of termites from the family Kalotermitidae. Despite their impressive morphological complexity and diversity, few species have been formally described and fewer still have been characterized at the molecular level. In this study, four novel species of calonymphids were isolated and characterized: Calonympha chia and Snyderella yamini spp. nov., from Neotermes castaneus and Calcaritermes nearcticus from Florida, USA, and Snyderella kirbyi and Snyderella swezyae, spp. nov., from Calcaritermes nigriceps and Cryptotermes cylindroceps from Colombia. Each of these species was distinguished from its congeners by residing in a distinct host and by differences at the molecular level. Phylogenetic analyses of small subunit (SSU) rDNA indicated that the genera Calonympha and Stephanonympha were probably not monophyletic, though the genus Snyderella, previously only represented by one sequence in molecular analyses, appeared with these new data to be monophyletic. This was in keeping with the traditional evolutionary view of the group in which the morphology of the genus Snyderella is considered to be derived, while that of the genus Stephanonympha is ancestral and therefore probably plesiomorphic.
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Affiliation(s)
- Gillian H. Gile
- Department of Botany, University of British Columbia, 3529-6270 University Boulevard, Vancouver, BC V6T 1Z4, Canada
| | - Erick R. James
- Department of Botany, University of British Columbia, 3529-6270 University Boulevard, Vancouver, BC V6T 1Z4, Canada
| | - Rudolf H. Scheffrahn
- University of Florida Research & Education Center, 3205 College Avenue, Davie, FL 33314, USA
| | - Kevin J. Carpenter
- Department of Botany, University of British Columbia, 3529-6270 University Boulevard, Vancouver, BC V6T 1Z4, Canada
| | - James T. Harper
- Department of Biology, Douglas College, 700 Royal Avenue, New Westminster, BC V3M 5Z5, Canada
- Department of Botany, University of British Columbia, 3529-6270 University Boulevard, Vancouver, BC V6T 1Z4, Canada
| | - Patrick J. Keeling
- Department of Botany, University of British Columbia, 3529-6270 University Boulevard, Vancouver, BC V6T 1Z4, Canada
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20
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Phylogenetic position of Lophomonas striata Bütschli (Parabasalia) from the hindgut of the cockroach Periplaneta americana. Protist 2011; 163:274-83. [PMID: 21840257 DOI: 10.1016/j.protis.2011.07.002] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2011] [Accepted: 06/26/2011] [Indexed: 11/22/2022]
Abstract
Lophomonas striata is a multiflagellate parabasalid commensal in the hindgut of the omnivorous cockroaches Blatta orientalis and Periplaneta americana. Its closest relatives were traditionally thought to include similar multiflagellate parabasalids with a single flagellar area that degenerates during mitosis, such as Joenia and Kofoidia. However, molecular phylogenetic analyses have shown that "lophomonads" are not monophyletic. We have determined the SSU rRNA sequence of L. striata and we find that it branches sister to the Trichonymphida with strong support. This is surprising because all other lophomonads sampled to date branch within the Cristamonadida, and the order Trichonymphida (e.g. Trichonympha, Pseudotrichonympha, and Hoplonympha) is both morphologically coherent and monophyletic in SSU rRNA phylogenies. Trichonymphida, unlike the lophomonads, share a bilateral symmetry, in which their multiple flagella occur in two (or sometimes four) regions, and instead of degenerating upon mitosis, half of the flagella are passed to each daughter cell. The single apical flagellar region characteristic of lophomonads is therefore either plesiomorphic or it has arisen multiple times in parabasalids; our phylogenetic analyses and available ultrastructural evidence suggest the latter. Our results also suggest that parabasalid gut symbionts may have been vertically transmitted in cockroaches before the common ancestor of Cryptocercus and termites.
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21
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CARPENTER KEVINJ, HORAK ALES, CHOW LAWRENCE, KEELING PATRICKJ. Symbiosis, Morphology, and Phylogeny of Hoplonymphidae (Parabasalia) of the Wood-Feeding Roach Cryptocercus punctulatus. J Eukaryot Microbiol 2011; 58:426-36. [DOI: 10.1111/j.1550-7408.2011.00564.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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22
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Critical Taxonomic Revision of Parabasalids with Description of one New Genus and three New Species. Protist 2010; 161:400-33. [DOI: 10.1016/j.protis.2009.11.005] [Citation(s) in RCA: 101] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2009] [Accepted: 11/21/2009] [Indexed: 11/17/2022]
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23
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Phylogenetic Position and Morphology of Spirotrichosomidae (Parabasalia): New Evidence from Leptospironympha of Cryptocercus punctulatus. Protist 2010; 161:122-32. [DOI: 10.1016/j.protis.2009.06.003] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2009] [Accepted: 06/14/2009] [Indexed: 11/22/2022]
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24
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Molecular identification and phylogenetic relationships of trichomonad isolates of galliform birds inferred from nuclear small subunit rRNA gene sequences. Parasitol Res 2009; 106:163-70. [DOI: 10.1007/s00436-009-1643-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2009] [Accepted: 09/18/2009] [Indexed: 10/20/2022]
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25
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Noda S, Mantini C, Bordereau C, Kitade O, Dolan MF, Viscogliosi E, Ohkuma M. Molecular phylogeny of parabasalids with emphasis on the order Cristamonadida and its complex morphological evolution. Mol Phylogenet Evol 2009; 52:217-24. [PMID: 19306937 DOI: 10.1016/j.ympev.2009.03.011] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2008] [Revised: 02/14/2009] [Accepted: 03/16/2009] [Indexed: 11/15/2022]
Abstract
Parabasalia represents a complex assemblage of species, which recently received extensive reorganization. The newly created order Cristamonadida unites complex hypermastigids belonging to the Lophomonadida like the joeniids, the multinucleate polymonad Calonymphidae, and well-developed trichomonads in the Devescovinidae. All these protists exclusively occur in the guts of termites and related insects. In this study, small subunit rRNA and glyceraldehyde-3-phosphate dehydrogenase genes were identified without cultivation from 14 species in Cristamonadida including previously unstudied genera such as Joenina, Joenia, Joenoides, Macrotrichomonas, Gigantomonas, and Foaina. Despite the great morphological diversity of Cristamonadida, our phylogenetic analyses supported the monophyly of this order. However, almost all the families and subfamilies composing this order are polyphyletic suggesting a complicated morphological evolution. Our analyses also showed that Cristamonadida descends from one lineage of rudimentary trichomonads and that joeniids was basal in this order. Several successive and independent morphological transitions such as the development and reduction of flagellar apparatus and associated cytoskeleton and transition to multinucleated status have likely led to the diversity and complexity of cristamonad lineages.
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Affiliation(s)
- Satoko Noda
- Ecomolecular Biorecycling Science Research Team, RIKEN Advanced Science Institute, Hirosawa 2-1, Wako, Saitama 351-0198, Japan
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26
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Carpenter KJ, Keeling PJ. Morphology and phylogenetic position of Eucomonympha imla (Parabasalia: Hypermastigida). J Eukaryot Microbiol 2008; 54:325-32. [PMID: 17669157 DOI: 10.1111/j.1550-7408.2007.00263.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Eucomonympha imla is a hypermastigote parabasalian found in the gut of the wood-feeding cockroach Cryptocercus punctulatus. It has received little attention since its original description in 1934 as the type species of the genus Eucomonympha and the family Eucomonymphidae. We used light and scanning electron microscopy to characterize surface morphology and organelles, with particular attention to the form of the rostrum, operculum, nucleus, and parabasals. Two previously unrecognized groups of bacterial ectobionts were observed-spirochetes that associate with the flagella and one or more types of rod-shaped bacteria that adhere to the cell surface. The small subunit rRNA (SSU rRNA) sequence was determined from manually isolated cells, and phylogenetic analyses place E. imla in a strongly supported clade with the genera Teranympha and Pseudotrichonympha and three sequences from formally undescribed termite symbionts provisionally assigned to Eucomonympha. Unexpectedly, the Eucomonympha isolates from termites are more closely related to Teranympha than to the type species, suggesting these should not be classified as species of Eucomonympha, despite their morphological similarity to E. imla. Eucomonymphidae fall within a strongly supported Trichonymphida (also including Hoplonymphidae, Trichonymphidae, and Staurojoeninidae), but this clade branches separately from other hypermastigote groups (lophomonads and spirotrichonymphids), suggesting that hypermastigotes are polyphyletic.
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Affiliation(s)
- Kevin J Carpenter
- Botany Department, Canadian Institute for Advanced Research, University of British Columbia, 3529-6270 University Boulevard, Vancouver, BC, Canada V6T 1Z4
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27
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Noël C, Noda S, Mantini C, Dolan MF, Moriya S, Delgado-Viscogliosi P, Kudo T, Capron M, Pierce RJ, Ohkuma M, Viscogliosi E. Molecular phylogenetic position of the genera Stephanonympha and Caduceia (Parabasalia) inferred from nuclear small subunit rRNA gene sequences. J Eukaryot Microbiol 2007; 54:93-9. [PMID: 17300526 DOI: 10.1111/j.1550-7408.2006.00234.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Nuclear small subunit (SSU) rRNA gene sequences were obtained by polymerase chain reaction from trichomonad symbionts of termites that belong to the Devescovinidae (Caduceia versatilis) and polymastigont Calonymphidae (Stephanonympha nelumbium). The unidentified SSU rRNA sequence Nk3, previously obtained from the termite Neotermes koshunensis, has also been shown to derive from a Stephanonympha sp. by in situ hybridization. These sequences were analysed in a broad phylogeny including nearly all identified parabasalid sequences available in the databases, and some as yet unidentified sequences likely deriving from the new order Cristamonadida (Devescovinidae, Calonymphidae, and hypermastigids Lophomonadida). A global phylogeny of parabasalids reveals a partial agreement between the clades identified in this work and the last classification of this phylum into four orders. However, this classification is still incongruent with our data and new taxonomic considerations are proposed. The analysis confirms the monophyly of the Cristamonadida and separates this order into two groups: the first unites nearly all the Devescovinidae including Caduceia and the Calonymphidae Coronympha and Metacoronympha, whereas the second group is composed of a few Devescovinidae, Lophomonadida, and Calonymphidae such as Stephanonympha. Caduceia is closely related to Devescovina, corroborating the marked morphological similarity between these two genera whereas Stephanonympha groups together with the Calonymphidae Snyderella and Calonympha. These data also confirm the polyphyly of the families Devescovinidae and Calonymphidae and support the arrangement of the axostyle-pelta complexes as a valuable character for taxonomic considerations within the Calonymphidae.
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Affiliation(s)
- Christophe Noël
- Inserm, U547, Institut Pasteur de Lille, 1 Rue du Professeur Calmette, BP 245, 59019 Lille cedex, France
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28
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An expanded inventory of conserved meiotic genes provides evidence for sex in Trichomonas vaginalis. PLoS One 2007; 3:e2879. [PMID: 18663385 PMCID: PMC2488364 DOI: 10.1371/journal.pone.0002879] [Citation(s) in RCA: 192] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2008] [Accepted: 06/08/2008] [Indexed: 12/23/2022] Open
Abstract
Meiosis is a defining feature of eukaryotes but its phylogenetic distribution has not been broadly determined, especially among eukaryotic microorganisms (i.e. protists)-which represent the majority of eukaryotic 'supergroups'. We surveyed genomes of animals, fungi, plants and protists for meiotic genes, focusing on the evolutionarily divergent parasitic protist Trichomonas vaginalis. We identified homologs of 29 components of the meiotic recombination machinery, as well as the synaptonemal and meiotic sister chromatid cohesion complexes. T. vaginalis has orthologs of 27 of 29 meiotic genes, including eight of nine genes that encode meiosis-specific proteins in model organisms. Although meiosis has not been observed in T. vaginalis, our findings suggest it is either currently sexual or a recent asexual, consistent with observed, albeit unusual, sexual cycles in their distant parabasalid relatives, the hypermastigotes. T. vaginalis may use meiotic gene homologs to mediate homologous recombination and genetic exchange. Overall, this expanded inventory of meiotic genes forms a useful "meiosis detection toolkit". Our analyses indicate that these meiotic genes arose, or were already present, early in eukaryotic evolution; thus, the eukaryotic cenancestor contained most or all components of this set and was likely capable of performing meiotic recombination using near-universal meiotic machinery.
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29
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Hampl V, Cepicka I, Flegr J, Tachezy J, Kulda J. Morphological and molecular diversity of the monocercomonadid genera Monocercomonas, Hexamastix, and Honigbergiella gen. nov. Protist 2007; 158:365-83. [PMID: 17499022 DOI: 10.1016/j.protis.2007.02.003] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2007] [Accepted: 02/24/2007] [Indexed: 10/23/2022]
Abstract
The family Monocercomonadidae (Parabasala, Trichomonadida) is characterized by the absence of a costa and in most species also of an undulating membrane; both of which are typical structures of trichomonadids. We have examined 25 isolates of Monocercomonadidae species by sequencing of the SSU rDNA and the ITS region and by light and transmission electron microscopy. The isolates formed three distinct phylogenetically unrelated clades: (1) Monocercomonas colubrorum, (2) Monocercomonas ruminantium together with a strain ATCC 50321 designated as Pseudotrichomonas keilini, and (3) Hexamastix. Twenty isolates of Monocercomonas colubrorum split into three clades with no host-specificity. The morphological differences among clades were insufficient to classify them as a separate species. Non-monophyly of the cattle commensal Monocercomonas ruminantium with the type species Monocercomonas colubrorum and absence of Pseudotrichomonas characters in the free-living strain ATCC 50321 led to their reclassification into a new genus (Honigbergiella gen. nov.). The close relationship of these strains indicates a recent switch between a free-living habit and endobiosis. Two strains of Hexamastix represented different species -Hexamastix kirbyi Honigberg 1955 and Hexamastix mitis sp. nov. Polyphyly of the Monocercomonadidae confirmed that the absence of a costa and an undulating membrane are not taxonomically significant characters and were probably secondarily lost in some or all clades. Our observations, however, indicated that other characters - infrakinetosomal body, comb-like structure, marginal lamella, and the type of axostyle - are fully consistent with the position of Monocercomonadidae species in the parabasalian tree and are, therefore, reasonable taxonomic characters.
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MESH Headings
- Animals
- DNA, Protozoan/chemistry
- DNA, Protozoan/genetics
- DNA, Ribosomal/chemistry
- DNA, Ribosomal/genetics
- DNA, Ribosomal Spacer/genetics
- Genes, rRNA
- Microscopy, Electron, Transmission
- Molecular Sequence Data
- Organelles/ultrastructure
- Phylogeny
- RNA, Protozoan/genetics
- RNA, Ribosomal, 18S/genetics
- Sequence Analysis, DNA
- Sequence Homology, Nucleic Acid
- Trichomonadida/classification
- Trichomonadida/cytology
- Trichomonadida/genetics
- Trichomonadida/ultrastructure
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Affiliation(s)
- Vladimír Hampl
- Department of Parasitology, Charles University in Prague, Prague, Czech Republic.
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30
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Ohkuma M, Saita K, Inoue T, Kudo T. Comparison of four protein phylogeny of parabasalian symbionts in termite guts. Mol Phylogenet Evol 2006; 42:847-53. [PMID: 17098447 DOI: 10.1016/j.ympev.2006.09.016] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2005] [Revised: 09/22/2006] [Accepted: 09/22/2006] [Indexed: 11/27/2022]
Affiliation(s)
- Moriya Ohkuma
- Environmental Molecular Biology Laboratory, RIKEN, Wako, Saitama 351-0198, Japan.
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31
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Brugerolle G. Comparative Cytological Study of Four Species in the Genera Holomastigotes and Uteronympha n. comb. (Holomastigotidae, Parabasalia), Symbiotic Flagellates of Termites. J Eukaryot Microbiol 2006; 53:246-59. [PMID: 16872292 DOI: 10.1111/j.1550-7408.2006.00107.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
Cytological features observed using light, immunofluorescence, and electron microscopy of the type species Holomastigotes elongatum were compared with Holomastigotes lanceolata and to Holomastigotes flexuosum n. sp. The comparison was extended to Spirotrichonymphella pudibunda and to Uteronympha africana n. gen. n. sp., in order to present the common features of the Holomastigotidae (Spirotrichonymphida). All these species have anterior basal bodies bearing microfibrillar or striated rootlets that are reduced or absent posterior to the nucleus. An axostylar trunk is present in Holomastigotes elongatum and Holomastigotes lanceolata, whereas the axostylar microtubules do not extend posterior to the nucleus in Holomastigotes flexuosum, Spirotrichonymphella, and Uteronympha. Uteronympha africana has specific features, such as a transverse plaque inside the columella from which arise microtubules capping the nucleus, and as in Spirotrichonympha the striated lamina is present all along the flagellar lines. Uteronympha africana has ability to endocytose wood particles in addition to the osmotrophic feeding that occurs in all the Holomastigotidae.
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Affiliation(s)
- Guy Brugerolle
- Biologie des Protistes, UMR 6023, CNRS and Université Blaise Pascal de Clermont-Ferrand, F-63177 Aubière Cedex, France.
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32
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Maass A, Radek R. The gut flagellate community of the termite Neotermes cubanus with special reference to Staurojoenina and Trichocovina hrdyi nov. gen. nov. sp. Eur J Protistol 2006; 42:125-41. [PMID: 17070758 DOI: 10.1016/j.ejop.2006.03.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2005] [Revised: 03/23/2006] [Accepted: 03/31/2006] [Indexed: 11/20/2022]
Abstract
At least seven species of flagellates have been found to inhabit the paunch of the termite Neotermes cubanus. Staurojoenina sp. is the largest species, measuring 100-150mum in length. Three small parabasalids belong to the genera Tritrichomonas, Metadevescovina, and Foaina. A fourth small type is described as Trichocovina hrdyi nov. gen. nov. sp.; the combination of features in this flagellate, such as the presence of a costa, undulating membrane and spiralled dictyosome, does not fit to any known genus. The two oxymonad species do not possess a rostellum. One belongs to the family Polymastigidae; it has one unattached flagellum and three partially attached flagella. The second is a member of the family Pyrsonymphidae, but this one possesses ring-like surface structures, one free flagellum and three spirally attached flagella. It is the first report of a pyrsonymphid in a kalotermitid termite.
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Affiliation(s)
- Annelie Maass
- Pathology, Institute of Ophthalmology, University College London, 11-43 Bath Street, London EC1V 9EL, UK
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Cepicka I, Hampl V, Kulda J, Flegr J. New evolutionary lineages, unexpected diversity, and host specificity in the parabasalid genus Tetratrichomonas. Mol Phylogenet Evol 2006; 39:542-51. [PMID: 16473027 DOI: 10.1016/j.ympev.2006.01.005] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2005] [Revised: 12/12/2005] [Accepted: 01/05/2006] [Indexed: 11/27/2022]
Abstract
We studied morphological and molecular polymorphism of 53 Tetratrichomonas isolates obtained from amphibian, reptilian, mammalian hosts, and from a slug with the aid of protargol staining and analyses of ITS1-5.8S rRNA-ITS2, SSU rRNA, and alpha-tubulin gene sequences. The phylogenetic tree based on the concatenate of all sequences showed the monophyly of the genus Tetratrichomonas with respect to the genus Trichomonas. Our data suggest that two parabasalid genera, Pentatrichomonoides and Trichomonoides, may belong to the genus Tetratrichomonas. Tetratrichomonas isolates were divided into 16 robust host-specific and monophyletic groups that probably represent separate, mostly new, species. As only five Tetratrichomonas species were described from the examined host taxa so far, our study uncovered considerable species diversity within the genus. The wide host range, high level of species-specific host specificity, and newly revealed biodiversity make the genus Tetratrichomonas a valuable model for studying evolution of parasites.
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Affiliation(s)
- Ivan Cepicka
- Department of Parasitology, Faculty of Science, Charles University, Prague, Czech Republic.
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Brugerolle G. The symbiotic fauna of the African termite Hodotermes mossambicus identification of four flagellate species of the genera Spironympha, Trichomonoides and Retortamonas. Parasitol Res 2005; 98:257-63. [PMID: 16369849 DOI: 10.1007/s00436-005-0002-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2005] [Accepted: 07/25/2005] [Indexed: 11/25/2022]
Abstract
Two Spironympha species were described by light immunofluorescence and electron microscopy. Spironympha fibrosa n. sp. has a narrow columella, several axostylar fibres and original striated myoneme-like fibres attached to the last basal body of each flagellar line. Spironympha simplex n. sp. is small and has non-striated microfibrils attached to the basal body section and an axostyle composed of two fibres. Trichomonas termitidis, as reported by Dogiel (Researches on parasitic protozoa from the intestine of termites. II. Lophomonadidae. Sci Res Zool Exped Brit E Africa made by Prof. V. Dogiel and I. Sokolow in 1914 10:20-35, 1917), has the features of Trichomonoides trypanoides, as reported by Brugerolle and Bordereau (Eur J Protistol 40:163-174, 2004). Retortamonas hodotermitis n. sp. shares the characteristics of insect retortamonads, as reported by Brugerolle (Protistologica 8:233-240, 1976), but does not correspond to any species described to date. The species identification differs from that of described in Dogiel (Russkii Arkhiv Protistologii 1:172-234, 1922).
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Affiliation(s)
- Guy Brugerolle
- Biologie des Protistes, Université Blaise Pascal de Clermont-Ferrand, Aubière, France.
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Brugerolle G. The flagellates of the termite Hodotermopsis sjoestedti: Immunological and ultrastructural characterization of four new species in the genera Spirotrichonympha, Spironympha and Microjoenia. Eur J Protistol 2005. [DOI: 10.1016/j.ejop.2005.06.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Ohkuma M, Iida T, Ohtoko K, Yuzawa H, Noda S, Viscogliosi E, Kudo T. Molecular phylogeny of parabasalids inferred from small subunit rRNA sequences, with emphasis on the Hypermastigea. Mol Phylogenet Evol 2005; 35:646-55. [PMID: 15878133 DOI: 10.1016/j.ympev.2005.02.013] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2004] [Revised: 02/03/2005] [Accepted: 02/21/2005] [Indexed: 10/25/2022]
Abstract
Small subunit rRNA gene sequences were identified without cultivation from parabasalid symbionts of termites belonging to the hypermastigid orders Trichonymphida (the genera Hoplonympha, Staurojoenina, Teranympha, and Eucomonympha) and Spirotrichonymphida (Spirotrichonymphella), and from four yet-unidentified parabasalid symbionts of the termite Incisitermes minor. All these new sequences were analyzed by Bayesian, likelihood, and parsimony methods in a broad phylogeny including all identified parabasalid sequences available in databases and some as yet unidentified sequences probably derived from hypermastigids. A salient point of our study focused on hypermastigids was the polyphyly of this class. We also noted a clear dichotomy between Trichonymphida and the other parabasalid taxa. However, this hypermastigid order was apparently polyphyletic, probably reflecting its morphological diversity. Among Trichonymphida, Teranympha (Teranymphidae) grouped together with the members of the family Eucomonymphidae, suggesting that its family status is ambiguous. The monophyletic lineage composed by Spirotrichonymphida exhibited a narrower branching pattern than Trichonymphida. The root of parabasalids was examined but could not be discerned accurately.
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Affiliation(s)
- Moriya Ohkuma
- Environmental Molecular Biology Laboratory, RIKEN, Wako, Saitama 351-0198, Japan.
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Hampl V, Cepicka I, Flegr J, Tachezy J, Kulda J. Critical analysis of the topology and rooting of the parabasalian 16S rRNA tree. Mol Phylogenet Evol 2005; 32:711-23. [PMID: 15288049 DOI: 10.1016/j.ympev.2004.03.005] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2003] [Revised: 03/01/2004] [Indexed: 11/22/2022]
Abstract
The morphological classification of the protozoan phylum Parabasala is not in absolute agreement with the 16S rRNA phylogeny. However, there are strong indications that tree-construction artifacts play a considerable role in the shaping of the 16S rRNA tree. We have performed rigorous analyses designed to minimize such artifacts using the slow-fast and taxa-exclusion methods. The analyses, which included new sequences from the genera Monocercomonas and Hexamastix, in most respects confirmed the previously suggested tree topology and polyphyly of Hypermastigida and Monocercomonadidae but detected one artificial cluster of long branches (Trichonymphidae, Pseudotrichonymphidae, Hexamastix, and Tricercomitus). They also indicated that the rooting of the phylum on the trichonymphid branch is probably wrong and that reliable rooting on the basis of current data is likely impossible. We discuss the tree topology in the view of anagenesis of cytoskeletal and motility organelles and suggest that a robust taxonomic revision requires extensive analysis of other gene sequences.
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Affiliation(s)
- Vladimír Hampl
- Department of Parasitology, Faculty of Science, Charles University, Prague, Czech Republic.
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Brugerolle G, Bordereau C. Pachyjoenia howa, a new symbiotic parabasalid joeniid flagellate of the termite Postelectrotermes howa. Eur J Protistol 2005. [DOI: 10.1016/j.ejop.2004.07.005] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Gerbod D, Sanders E, Moriya S, Noël C, Takasu H, Fast NM, Delgado-Viscogliosi P, Ohkuma M, Kudo T, Capron M, Palmer JD, Keeling PJ, Viscogliosi E. Molecular phylogenies of Parabasalia inferred from four protein genes and comparison with rRNA trees. Mol Phylogenet Evol 2004; 31:572-80. [PMID: 15062795 DOI: 10.1016/j.ympev.2003.09.013] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2003] [Revised: 09/01/2003] [Indexed: 11/22/2022]
Abstract
The molecular phylogeny of parabasalids has mainly been inferred from small subunit (SSU) rRNA sequences and has conflicted substantially with systematics based on morphological and ultrastructural characters. This raises the important question, how congruent are protein and SSU rRNA trees? New sequences from seven diverse parabasalids (six trichomonads and one hypermastigid) were added to data sets of glyceraldehyde-3-phosphate dehydrogenase (GAPDH), enolase, alpha-tubulin and beta-tubulin and used to construct phylogenetic trees. The GAPDH tree was well resolved and identical in topology to the SSU rRNA tree. This both validates the rRNA tree and suggests that GAPDH should be a valuable tool in further phylogenetic studies of parabasalids. In particular, the GAPDH tree confirmed the polyphyly of Monocercomonadidae and Trichomonadidae and the basal position of Trichonympha agilis among parabasalids. Moreover, GAPDH strengthened the hypothesis of secondary loss of cytoskeletal structures in Monocercomonadidae such as Monocercomonas and Hypotrichomonas. In contrast to GAPDH, the enolase and both tubulin trees are poorly resolved and rather uninformative about parabasalian phylogeny, although two of these trees also identify T. agilis as representing the basal-most lineage of parabasalids. Although all four protein genes show multiple gene duplications (for 3-6 of the seven taxa examined), most duplications appear to be relatively recent (i.e., species-specific) and not a problem for phylogeny reconstruction. Only for enolase are there more ancient duplications that may confound phylogenetic interpretation.
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Affiliation(s)
- Delphine Gerbod
- Department of Biology, Indiana University, Bloomington, IN 47405, USA
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Brugerolle G, Bordereau C. The flagellates of the termite Hodotermopsis sjoestedti with special reference to Hoplonympha, Holomastigotes and Trichomonoides trypanoides n. comb. Eur J Protistol 2004. [DOI: 10.1016/j.ejop.2004.05.001] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Brugerolle G, Silva-Neto ID, Pellens R, Grandcolas P. Electron microscopic identification of the intestinal protozoan flagellates of the xylophagous cockroach Parasphaeria boleiriana from Brazil. Parasitol Res 2003; 90:249-56. [PMID: 12783316 DOI: 10.1007/s00436-003-0832-7] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2002] [Accepted: 12/12/2002] [Indexed: 11/25/2022]
Abstract
Flagellate protozoa of the hindgut of the xylophagous blattid Parasphaeria boleiriana were examined by light and electron microscopy. This species harbours two oxymonad species of the genera Monocercomonoides and Polymastix, the latter bearing Fusiformis bacteria on its surface. A diplomonad was present and has features of the genus Hexamita rather than Spironucleus. In addition, two trichomonads of the genera Monocercomonas and Tetratrichomastix were identified. A precise comparison with species of blattids and other insects was difficult because most of these flagellates have been described only by light microscopy after cell staining and there are few electron microscope studies and no molecular studies. None of the flagellates contained wood fragments in their food vacuoles and so evidently do not participate in the digestion of wood or cellulose.
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Affiliation(s)
- G Brugerolle
- Biologie des Protistes, UMR 6023 CNRS and Université Blaise Pascal de Clermont-Ferrand, 63177 Aubière Cedex, France.
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Keeling PJ, Leander BS. Characterisation of a non-canonical genetic code in the oxymonad Streblomastix strix. J Mol Biol 2003; 326:1337-49. [PMID: 12595248 DOI: 10.1016/s0022-2836(03)00057-3] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The genetic code is one of the most highly conserved characters in living organisms. Only a small number of genomes have evolved slight variations on the code, and these non-canonical codes are instrumental in understanding the selective pressures maintaining the code. Here, we describe a new case of a non-canonical genetic code from the oxymonad flagellate Streblomastix strix. We have sequenced four protein-coding genes from S.strix and found that the canonical stop codons TAA and TAG encode the amino acid glutamine. These codons are retained in S.strix mRNAs, and the legitimate termination codons of all genes examined were found to be TGA, supporting the prediction that this should be the only true stop codon in this genome. Only four other lineages of eukaryotes are known to have evolved non-canonical nuclear genetic codes, and our phylogenetic analyses of alpha-tubulin, beta-tubulin, elongation factor-1 alpha (EF-1 alpha), heat-shock protein 90 (HSP90), and small subunit rRNA all confirm that the variant code in S.strix evolved independently of any other known variant. The independent origin of each of these codes is particularly interesting because the code found in S.strix, where TAA and TAG encode glutamine, has evolved in three of the four other nuclear lineages with variant codes, but this code has never evolved in a prokaryote or a prokaryote-derived organelle. The distribution of non-canonical codes is probably the result of a combination of differences in translation termination, tRNAs, and tRNA synthetases, such that the eukaryotic machinery preferentially allows changes involving TAA and TAG.
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Affiliation(s)
- Patrick J Keeling
- Department of Botany, Canadian Institute for Advanced Research, University of British Columbia, 3529-6270 University Boulevard, Vancouver, BC, Canada V6T 1Z4.
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Brugerolle G, Bordereau C. Ultrastructure of Joenoides intermedia (Grassé 1952), a symbiotic parabasalid flagellate of Hodotermes mossambicus, and its comparison with other joeniid genera. Eur J Protistol 2003. [DOI: 10.1078/0932-4739-00898] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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