A Novel Method to Generate MNase Ladders Reveal Rapid Chromatin Remodeling upon Gametogenesis and Mating in Chlamydomonas
Publication date: Available online 17 July 2018Source: ProtistAuthor(s): Pooja Potdar, Patricia Pinto, Nicole D’Souza, Prajakta Joshi, Akshay Malwade, Subhojit SenTo circumvent nuclei isolation for nucleosomal mapping of wild-type (cell walled) algal cells, we developed a quick and versatile methodology, by abrasion of whole cells (Chlamydomonas, Scenedesmus and yeast), allowing Micrococcal Nuclease (MNase) direct access to nuclear chromatin, in situ. Varying parameters such as bead abrasion, vortex and incubation conditions, we optimized capture of an ‘early digest’ which may probe chromatin differentially, based on...
Source: Protist - July 18, 2018 Category: Molecular Biology Source Type: research
Epizoic and Apochlorotic Tursiocola species (Bacillariophyta) from the Skin of Florida Manatees (Trichechus manatus latirostris)
Publication date: Available online 16 April 2018Source: ProtistAuthor(s): Thomas A. Frankovich, Matt P. Ashworth, Michael J. Sullivan, Edward C. Theriot, Nicole I. StacyUntil now only one group of diatoms, the Bacillariaceae, was known to contain heterotrophic representatives. We show that a second group, represented by species in the genus Tursiocola, has undergone evolutionary loss of photosynthesis within the Bacillariophyta. Heterotrophy was evidenced by the presence of only apochlorotic cells in live and motile specimens. Three species of Tursiocola (T. bondei sp. nov., T. alata sp. nov., and T. gracilis sp. nov.), of...
Source: Protist - July 10, 2018 Category: Molecular Biology Source Type: research
Revision of the Genus Chroomonas Hansgirg: The Benefits of DNA-containing Specimens
In this study, material of Hansgirg’s C. nordstedtii was subjected to PCR and to sequencing of two short DNA tags. These tags allowed for an unambiguous identification of the real C. nordstedtii in the phylogeny of the blue-green cryptophytes. The genus Chroomonas corresponds to subclade 1, whereas subclades 3 and 4 do not belong to Chroomonas, if Hemiselmis is maintained. Additional examination by light and scanning electron microscopy and by spectrophotometry demonstrate that subclade 1 comprises only cells with hexagonal periplast plates and PC 630, whereas rectangular periplast plates are found only in subclades 3 an...
Source: Protist - July 10, 2018 Category: Molecular Biology Source Type: research
First Ultrastructural and Molecular Phylogenetic Evidence from the Blastogregarines, an Early Branching Lineage of Plesiomorphic Apicomplexa
Publication date: Available online 23 April 2018Source: ProtistAuthor(s): Timur G. Simdyanov, Gita G. Paskerova, Andrea Valigurová, Andrei Diakin, Magdaléna Kováčiková, Joseph Schrével, Laure Guillou, Andrey A. Dobrovolskij, Vladimir V. AleoshinBlastogregarines are poorly studied parasites of polychaetes superficially resembling gregarines, but lacking syzygy and gametocyst stages in the life cycle. Furthermore, their permanent multinuclearity and gametogenesis by means of budding considerably distinguish them from other parasitic Apicomplexa such as coccidians and haematozoans. The affiliation of blastogregarines ha...
Source: Protist - July 10, 2018 Category: Molecular Biology Source Type: research
The Uncoupled Assimilation of Carbon and Nitrogen from Urea and Glycine by the Bloom-forming Dinoflagellate Prorocentrum minimum
Publication date: Available online 5 June 2018Source: ProtistAuthor(s): Olga Matantseva, Ilya Pozdnyakov, Maren Voss, Iris Liskow, Sergei SkarlatoThe spread of harmful dinoflagellate blooms has been linked to the increasing availability of nitrogen, including its dissolved organic forms. The relationships between organic and inorganic nutrient uptake by dinoflagellates are not completely understood; moreover, it is not clear whether organic substances are used exclusively as nitrogen or also as carbon sources. We used laboratory culture experiments to investigate the concurrent uptake of glycine and nitrate by Prorocentrum...
Source: Protist - July 10, 2018 Category: Molecular Biology Source Type: research
Yogsothoth knorrus gen. n., sp. n. and Y. carteri sp. n. (Yogsothothidae fam. n., Haptista, Centroplasthelida), with Notes on Evolution and Systematics of Centrohelids
Publication date: Available online 18 June 2018Source: ProtistAuthor(s): Yegor Shishkin, Daria Drachko, Vladimir I. Klimov, Vasily V. ZlatogurskyTwo closely related new species of centrohelid heliozoans with unusual morphology were studied with light and electron microscopy. Sequences of the 18S rRNA gene were also obtained and secondary structure of 18S rRNA molecule reconstructed. The cells, covered with inner siliceous plate scales formed colonies. The entire colony was surrounded with a thick layer of external scales. Inner scales were tabulate and had a patternless surface, except for the presence of an axial rib. Out...
Source: Protist - July 10, 2018 Category: Molecular Biology Source Type: research
Nutritional Intake by Ectoplasmic Nets of Schizochytrium aggregatum (Labyrinthulomycetes, Stramenopiles)
Publication date: Available online 18 June 2018Source: ProtistAuthor(s): Izumi Iwata, Daiske HondaThraustochytrid cells attach to their food via ectoplasmic nets (ENs). Here, we analyzed the cause and effect relationship between the various forms and functions of ENs of Schizochytrium aggregatum. The ENs spread out over a large area forming a fine network to efficiently search for the experimental food source. After recognizing the experimental food source, the ENs that attached to the food source became thicker, and net elements developed. The thick ENs on the surface at the attachment site were enveloped in dense materia...
Source: Protist - July 10, 2018 Category: Molecular Biology Source Type: research
Quantitative Response of Alexandrium catenella Cyst Dormancy to Cold Exposure
This study examines the effect of cold exposure on the duration of dormancy in Alexandrium catenella, a HAB dinoflagellate that causes paralytic shellfish poisoning (PSP). Mature, dormant cysts from Nauset Marsh (Cape Cod, MA USA) were stored at low but above freezing temperatures for up to six months. Dormancy status was then determined at regular intervals using a germination assay. Dormancy timing was variable among temperatures and was shorter in colder treatments, but the differences collapse when temperature and duration of storage are scaled by chilling-units (CU), a common horticultural predictor of plant and insec...
Source: Protist - July 10, 2018 Category: Molecular Biology Source Type: research
Structure and Development of the Auxospore in Ardissonea crystallina (C. Agardh) Grunow Demonstrates Another Way for a Centric to Look Like a Pennate
Publication date: Available online 20 June 2018Source: ProtistAuthor(s): Irena Kaczmarska, James M. Ehrman, Nickolai A. Davidovich, Olga I. Davidovich, Yulia A. PodunayReproductive development in Ardissonea crystallina revealed a unique mode of enlargement involving a combination of novel and known structures. In light microscopy, auxospores of this elongated polar centric diatom were superficially similar to the auxospores of pennates. With SEM we found three different components in the auxospore wall. In the youngest, nearly spherical cell-stage, the wall consisted only of a delicate veil containing minute siliceous sphe...
Source: Protist - July 10, 2018 Category: Molecular Biology Source Type: research
Fine structure and Molecular Phylogenetic Position of Two Marine Gregarines, Selenidium pygospionis sp. n. and S. pherusae sp. n., with Notes on the Phylogeny of Archigregarinida (Apicomplexa)
Publication date: Available online 28 June 2018Source: ProtistAuthor(s): Gita G. Paskerova, Tatiana S. Miroliubova, Andrei Diakin, Magdaléna Kováčiková, Andrea Valigurová, Laure Guillou, Vladimir V. Aleoshin, Timur G. SimdyanovArchigregarines are a key group for understanding the early evolution of Apicomplexa. Here we report morphological, ultrastructural, and molecular phylogenetic evidence from two archigregarine species: Selenidium pygospionis sp. n. and S. pherusae sp. n. They exhibited typical features of archigregarines. Additionally, an axial row of vacuoles of a presumably nutrient distribution system was rev...
Source: Protist - July 10, 2018 Category: Molecular Biology Source Type: research
Molecular and Morphological Diversity of the Oxymonad Genera Monocercomonoides and Blattamonas gen. nov
Publication date: Available online 30 June 2018Source: ProtistAuthor(s): Sebastian C. Treitli, Michael Kotyk, Naoji Yubuki, Eliška Jirounková, Jitka Vlasáková, Pavla Butovičová, Petr Šípek, Ivan Čepička, Vladimír HamplOxymonads are a group of flagellates living as gut symbionts of insects or vertebrates. They have several unique features, one of them being the absence of mitochondria. Diversity of this group is seriously understudied, which is particularly true for small species from the Polymastigidae family. We isolated 34 strains of oxymonads with Polymastigidae-like morphology from 24 host species and unused...
Source: Protist - July 10, 2018 Category: Molecular Biology Source Type: research
New Taxa of Streptophyte Algae (Streptophyta) from Terrestrial Habitats Revealed Using an Integrative Approach
Publication date: July 2018Source: Protist, Volume 169, Issue 3Author(s): Tatiana Mikhailyuk, Alena Lukešová, Karin Glaser, Andreas Holzinger, Sabrina Obwegeser, Svetlana Nyporko, Thomas Friedl, Ulf KarstenTwo new genera (Streptosarcina and Streptofilum) and three new species (Streptosarcina arenaria, S. costaricana and Streptofilum capillatum) of streptophyte algae were detected in cultures isolated from terrestrial habitats of Europe and Central America and described using an integrative approach. Additionally, a strain isolated from soil in North America was identified as Hormidiella parvula and proposed as an epitype...
Source: Protist - July 10, 2018 Category: Molecular Biology Source Type: research
The Hidden Diversity of Flagellated Protists in Soil
Publication date: July 2018Source: Protist, Volume 169, Issue 3Author(s): Paul Christiaan Venter, Frank Nitsche, Hartmut ArndtProtists are among the most diverse and abundant eukaryotes in soil. However, gaps between described and sequenced protist morphospecies still present a pending problem when surveying environmental samples for known species using molecular methods. The number of sequences in the molecular PR2 database (∼130,000) is limited compared to the species richness expected (>1 million protist species) – limiting the recovery rate. This is important, since high throughput sequencing (HTS) methods are used...
Source: Protist - July 10, 2018 Category: Molecular Biology Source Type: research
Editorial Board
Publication date: July 2018Source: Protist, Volume 169, Issue 3Author(s): (Source: Protist)
Source: Protist - July 10, 2018 Category: Molecular Biology Source Type: research
Unprecedented Symbiont Eukaryote Diversity Is Governed by Internal Trophic Webs in a Wild Non-Human Primate
Publication date: July 2018Source: Protist, Volume 169, Issue 3Author(s): Justin J.S. Wilcox, Hope HollocherResearch on host-associated microbiomes has highlighted major divisions between the role of eukaryotes in free-living and symbiont systems. These trends call into question the relevance of macroecological processes to host-associated systems and the relative importance of parasitism, commensalism, and mutualism as evolutionary patterns across the domains of life. However, it is unclear as to whether these apparent differences reflect biological realities or methodologies in community characterization: free-living euk...
Source: Protist - July 10, 2018 Category: Molecular Biology Source Type: research
