Alternative Type II NAD(P)H Dehydrogenases in the Mitochondria of Protists and Fungi
Publication date: Available online 10 November 2018Source: ProtistAuthor(s): Nina Antos-Krzeminska, Wieslawa JarmuszkiewiczPlants, fungi, and some protists possess a more branched electron transport chain in their mitochondria compared to canonical one. In these organisms, the electron transport chain contains several rotenone-insensitive NAD(P)H dehydrogenases. Some are located on the outer surface, and others are located on the inner surface of the inner mitochondrial membrane. The putative role of these enzymes still remains elusive, but they may prevent the overreduction of the electron transport chain components and d...
Source: Protist - November 11, 2018 Category: Molecular Biology Source Type: research
Non-linear physiology and gene expression responses of Harmful Alga Heterosigma akashiwo to Rising CO2
Publication date: Available online 24 October 2018Source: ProtistAuthor(s): Gwenn M.M. Hennon, Olivia M. Williamson, María D. Hernández Limón, Sheean T. Haley, Sonya T. DyhrmanHeterosigma akashiwo is a raphidophyte known for forming ichthyotoxic blooms. In order to predict the potential impacts of rising CO2 on H. akashiwo it is necessary to understand the factors influencing growth rates over a range of CO2 concentrations. Here we examined the physiology and gene expression response of H. akashiwo to concentrations from 200 to 1000 ppm CO2. Growth rate data were combined from this and previous studies and fit with...
Source: Protist - October 25, 2018 Category: Molecular Biology Source Type: research
Phylogenomics of Thecamoebida (Discosea, Amoebozoa) with the Description of Stratorugosa tubuloviscum gen. nov. sp. nov., a Freshwater Amoeba with a Perinuclear MTOC
Publication date: Available online 16 October 2018Source: ProtistAuthor(s): James T. Melton, Fiona C. Wood, Jordan Branch, Mandakini Singla, Yonas I. TekleThecamoebida Smirnov and Cavalier-Smith, 2011 (Discosea, Amoebozoa) has been molecularly understudied. The group until recently consisted of three genera containing species that live in terrestrial or aquatic environments. Here, we describe a fourth genus, Stratorugosa tubuloviscum gen. nov. sp. nov., which was isolated from a freshwater Amoeba proteus Ward’s Science culture. Although this species most closely morphologically resembles a large, rugose Thecamoeba, S. tu...
Source: Protist - October 17, 2018 Category: Molecular Biology Source Type: research
Extensive Cryptic Diversity in the Terrestrial Diatom Pinnularia borealis (Bacillariophyceae)
In this study, we used morphometric analysis on light microscopy (LM) micrographs in SHERPA, detailed scanning electron microscopy (SEM), and cytological observations in LM to examine 70 clones belonging to eight distinct molecular lineages of the cosmopolitan terrestrial diatom Pinnularia borealis. Due to high within-lineage variation, no conclusive morphological separation in LM nor SEM could be detected. Morphological stasis due to the “low-morphology” problem or stabilizing selection, as well as parallel/convergent evolution, phenotypic plasticity and structural inheritance are discussed as potential drivers for th...
Source: Protist - October 14, 2018 Category: Molecular Biology Source Type: research
Xenophyophores (Rhizaria, Foraminifera) from the Eastern Clarion-Clipperton Zone (equatorial Pacific): The Genus Psammina
Publication date: Available online 5 October 2018Source: ProtistAuthor(s): Andrew J. Gooday, Maria Holzmann, Aurélie Goineau, Olga Kamenskaya, Vyacheslav F. Melnik, Richard B. Pearce, Alexandra Weber, Jan PawlowskiXenophyophores are important megafaunal organisms in the abyssal Clarion-Clipperton Zone (CCZ; equatorial Pacific), a region hosting commercially significant deposits of polymetallic nodules. Previous studies assigned those with attached, fan-like tests to Psammina limbata, a species described from the central CCZ based on morphology. Here, we redescribe the holotype of P. limbata and then show that limbata-like...
Source: Protist - October 5, 2018 Category: Molecular Biology Source Type: research
Tridimensional Electron Microscopy Analysis of the Early Endosomes and Endocytic Traffic in Trypanosoma cruzi Epimastigotes
Publication date: Available online 29 September 2018Source: ProtistAuthor(s): Carolina de L. lcantara, Wanderley de Souza, Narcisa L. da Cunha e SilvaTrypanosoma cruzi epimastigotes internalize macromolecules avidly by endocytosis. Previously, we identified a tubule-vesicular network likely to correspond to the early-endosomes. However, a detailed ultrastructural characterization of these endosomes was missing. Here, we combined endocytosis assays with ultrastructural data from high-resolution electron microscopy to produce a 3D analysis of epimastigote endosomes and their interactions with endocytic organelles. We showed ...
Source: Protist - October 5, 2018 Category: Molecular Biology Source Type: research
Editorial Board
Publication date: November 2018Source: Protist, Volume 169, Issue 5Author(s): (Source: Protist)
Source: Protist - September 13, 2018 Category: Molecular Biology Source Type: research
Corrigendum to “Tropidoatractidae fam. nov., a deep branching lineage of Metopida (Armophorea, Ciliophora) found in diverse habitats and possessing prokaryotic symbionts” [Protist 169 (July (3)) (2018) 362–405]
Publication date: November 2018Source: Protist, Volume 169, Issue 5Author(s): Johana Rotterová, William Bourland, Ivan Čepička (Source: Protist)
Source: Protist - September 13, 2018 Category: Molecular Biology Source Type: research
Phylogenetic Analysis Reveals that the ‘Radial Centric’ Diatom Orthoseira Thwaites (Orthoseiraceae, Bacillariophyta) is a Member of a ‘Multipolar’ Diatom Lineage
We present a five-gene phylogeny, based on nuclear (nSSU rDNA) and chloroplast (rbcL, psbC, psbA, and psaB) genes to determine the phylogenetic placement of Orthoseira among the diatoms. The concatenated multi-gene phylogenies and nSSU-only gene tree demonstrate that Orthoseira is deeply embedded within a clade of the Mediophyceae (‘multipolar centric’ diatoms). Throughout all phylogenetic analyses, Orthoseira was shown to be sister to the genera Terpsinoë and Hydrosera. Through comparison of topologies reflecting competing hypotheses about the placement of Orthoseira, it was determined that the hypothesis that Orthos...
Source: Protist - September 5, 2018 Category: Molecular Biology Source Type: research
Seeing is Believing: Diatoms and the Ocean Carbon Cycle Revisited
Publication date: Available online 27 August 2018Source: ProtistAuthor(s): Victor SmetacekTerrestrial ecologists and biogeochemists are in direct contact with their objects of study via sense organs evolved in those environments; they hence share a common awareness because they can all see the whole elephant, as in the ancient Indian parable. Pelagic ecologists and biogeochemists on the other hand are the blind men groping different parts of the elephant − the protist-dominated biome of the planet − in attempts to understand its structure and functioning in terms of organism life cycles and the biogenic elements of whi...
Source: Protist - August 28, 2018 Category: Molecular Biology Source Type: research
The Response of Three Southern Ocean Phytoplankton Species to Ocean Acidification and Light Availability: A Transcriptomic Study
Publication date: Available online 27 August 2018Source: ProtistAuthor(s): Sára Beszteri, Silke Thoms, Vladimir Benes, Lars Harms, Scarlett TrimbornOcean acidification (OA) and high light was found to negatively affect the Antarctic key species Phaeocystis antarctica, Fragilariopsis kerguelensis and Chaetoceros debilis. To unravel the underlying physiological response at the transcriptomic level, these species were grown under ambient and elevated pCO2 combined with low or high light. RNA sequencing revealed that the haptophyte was much more tolerant towards OA than the two diatoms as only these showed distinct OA-depende...
Source: Protist - August 28, 2018 Category: Molecular Biology Source Type: research
Phylogeny and Classification of Novel Diversity in Sainouroidea (Cercozoa, Rhizaria) Sheds Light on a Highly Diverse and Divergent Clade
Publication date: Available online 22 August 2018Source: ProtistAuthor(s): Gabriel A. Schuler, Alexander K. Tice, Rebecca A. Pearce, Emily Foreman, Jared Stone, Sarah Gammill, John D. Wilson, Chris Reading, Jeffrey D. Silberman, Matthew W. BrownSainouroidea is a molecularly diverse clade of cercozoan flagellates and amoebae in the eukaryotic supergroup Rhizaria. Previous 18S rDNA environmental sequencing of globally collected fecal and soil samples revealed great diversity and high sequence divergence in the Sainouroidea. However, a very limited amount of this diversity has been observed or described. The two described gen...
Source: Protist - August 23, 2018 Category: Molecular Biology Source Type: research
Molecular Investigation of the Ciliate Spirostomum semivirescens, with First Transcriptome and New Geographical Records
Publication date: Available online 20 August 2018Source: ProtistAuthor(s): Hunter N. Hines, Henning Onsbring, Thijs J.G. Ettema, Genoveva F. EstebanThe ciliate Spirostomum semivirescens is a large freshwater protist densely packed with endosymbiotic algae and capable of building a protective coating from surrounding particles. The species has been rarely recorded and it lacks any molecular investigations. We obtained such data from S. semivirescens isolated in the UK and Sweden. Using single-cell RNA sequencing of isolates from both countries, the transcriptome of S. semivirescens was generated. Phylogenetic analysis of th...
Source: Protist - August 21, 2018 Category: Molecular Biology Source Type: research
Allobodo chlorophagus n. gen. n. sp., a Kinetoplastid that Infiltrates and Feeds on the Invasive Alga Codium fragile
Publication date: Available online 1 August 2018Source: ProtistAuthor(s): Joshua D. Goodwin, Thomas F. Lee, Paul Kugrens, Alastair G.B. SimpsonA novel biflagellate protist that consumed chloroplasts inside material of the invasive marine green alga Codium fragile was reported from the U.S. east coast in 2003. We observed a similar association in C. fragile from five sites in Nova Scotia, Canada during 2013 and 2014. After incubating Codium fragments for 2-3 days, some utricles and filaments contained numerous chloroplast-consuming cells. Transmission electron microscopy (TEM) confirmed that these were kinetoplastids with a...
Source: Protist - August 2, 2018 Category: Molecular Biology Source Type: research
Editorial Board
Publication date: August 2018Source: Protist, Volume 169, Issue 4Author(s): (Source: Protist)
Source: Protist - July 29, 2018 Category: Molecular Biology Source Type: research
