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Frithjof C Kupper - One of the best experts on this subject based on the ideXlab platform.
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comparative immunofluorescence and ultrastructural analysis of microtubule organization in Uronema sp klebsormidium flaccidum k subtilissimum stichococcus bacillaris and s chloranthus chlorophyta
Protist, 2011Co-Authors: Christos Katsaros, Vasilios Varvarigos, Claire M M Gachon, Jerry J Brand, Taizo Motomura, Chikako Nagasato, Frithjof C KupperAbstract:A detailed comparative examination of microtubule (MT) organization in interphase and dividing cells of Uronema sp. , Klebsormidium flaccidum , K. subtilissimum , Stichococcus bacillaris and S. chloranthus was made using tubulin immunofluorescence and transmission electron microscopy (TEM). During interphase all the species bear a well-organized cortical MT system, consisting of parallel bundles with different orientations. In Uronema sp. the cortical MT bundles are longitudinally oriented, whereas in the other species they are in transverse orientation to the axis of the cells. Considerable differences in MT organization were also observed during stages of mitosis, mainly preprophase, as well as cytokinesis. In Uronema sp. , a particular radial MT assembly is organized during preprophase-early prophase, which was not observed in the other species. In Stichococcus a fine MT ring surrounded the nucleus during preprophase and prophase. An MT ring, together with single cytoplasmic MTs, was also found associated with the developing diaphragm during cytokinesis in Stichococcus . A phycoplast participates in cytokinesis in Uronema sp., but not in the other species. In Uronema sp . the centrosome functions as a microtubule organizing center (MTOC) during mitosis, but not during interphase and cytokinesis. The phylogenetic significance of these differences is discussed in combination with SSU/ITS sequencing and other, existing molecular data.
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Comparative immunofluorescence and ultrastructural analysis of microtubule organization combined with SSU / ITS sequencing in Uronema sp., Klebsormidium flaccidum, K. subtilissimum, Stichococcus bacillaris and S. chloranthus (Chlorophyta)
Protist, 2011Co-Authors: Christos Katsaros, Vasilios Varvarigos, Claire M M Gachon, Taizo Motomura, Chikako Nagasato, Jery Brand, Frithjof C KupperAbstract:A detailed comparative examination of microtubule (MT) organization in interphase and dividing cells of Uronema sp. , Klebsormidium flaccidum , K. subtilissimum , Stichococcus bacillaris and S. chloranthus was made using tubulin immunofluorescence and transmission electron microscopy (TEM). During interphase all the species bear a well-organized cortical MT system, consisting of parallel bundles with different orientations. In Uronema sp. the cortical MT bundles are longitudinally oriented, whereas in the other species they are in transverse orientation to the axis of the cells. Considerable differences in MT organization were also observed during stages of mitosis, mainly preprophase, as well as cytokinesis. In Uronema sp. , a particular radial MT assembly is organized during preprophase-early prophase, which was not observed in the other species. In Stichococcus a fine MT ring surrounded the nucleus during preprophase and prophase. An MT ring, together with single cytoplasmic MTs, was also found associated with the developing diaphragm during cytokinesis in Stichococcus . A phycoplast participates in cytokinesis in Uronema sp., but not in the other species. In Uronema sp . the centrosome functions as a microtubule organizing center (MTOC) during mitosis, but not during interphase and cytokinesis. The phylogenetic significance of these differences is discussed in combination with SSU/ITS sequencing and other, existing molecular data.
Weibo Song - One of the best experts on this subject based on the ideXlab platform.
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Separation and relationship of ten marine scuticociliates (Protozoa, Ciliophora) using RAPD fingerprinting method
Acta Oceanologica Sinica, 2020Co-Authors: Huimin Shang, Weibo SongAbstract:On the basis of the random amplified polymorphic DNA-fingerprinting (RAPD) method, 10 morphospecies of scuticociliates from 7 genera, including 15 clones of 13 strains, Uronema marinum, Uronema cf morinum, ParaUronema virginianum, P. longum, Metanophrys similis, M. sinensis, Paralembus digitiformis, Mesanophrys carcini, Paranophrys magna and Cohnilembus verminus were analysed using 8 oligonucleotide primers. The genetic similarity among the clones of the same strain measured by a band-sharing index is 0.97∼0.98, while 0.40∼0.52 among strains. This value measured is 0.39∼0.46 among congeners of the same genus, whereas 0.16-0.47 between different genera. A distance tree was constructed based on 8-primer analysis, in which the scuticociliates investigated were separated into two clusters: one consists of 2 genera, Uronema and ParaUronema, and the other was composed of five, Metanophrys, Mesanophrys, Paranophrys, Paralembus and Cohnilembus. It is demonstrated also that the morphospecies ParaUronema virginianum may be a species-complex, i. e., it contains different genospecies.
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Reinvestigations of Three “Well-known” Marine Scuticociliates: Uronemella filificum (Kahl, 1931) nov. gen., nov. comb., Pseud cohnilembus hargisi Evans & Thompson, 1964 and Cyclidium citrullus Cohn 1865, with Description of the New Genus Uronemella (
Zoologischer Anzeiger – A Journal of Comparative Zoology, 2020Co-Authors: Weibo Song, Norbert WilbertAbstract:Abstract The living morphology, infraciliature and silverline system of 3 “well-known” marine scuticociliates, Uronemella filificum (Kahl, 1931) nov. gen., nov. comb. (formerly Uronema filificum Kahl, 1931), Pseudocohnilembus hargisi Evans & Thompson, 1964 and Cyclidium citrullus Cohn 1865 are reinvestigated and redescribed. Based on the data obtained, we suggest an establishment of a new genus Uronemella. The diagnosis for the new taxon: thigmotactic Uronematidae with generally pear-shaped body and subequatorially positioned cytostome; apical plate dominant; oral apparatus Uronema-like, one-rowed membranelle 1 about as long as membranelle 2; paroral membrane extending anteriorly to about mid-level of membrane 2; one caudal cilium; in vivo exhibiting typical rotatory movement with help of a caudal-cilium-associated sticky thread; generally in marine habitats. According to this definition, three nominal species as new combinations are transferred into this genus: Uronemella binucleata (Song, 1993) nov. comb. (= Homalogastra binucleata Song, 1993), Uronemella filificum (Kahl, 1931) nov. comb. (= Uronema filificum Kahl, 1931) and Uronemella cymruensis (Perez-Uz & Hope, 1997) nov. comb. (=Urocyclon cymruensis Perez-Uz & Hope, 1997). For comparison with Uronemella, some other closely-related taxa are also briefly outlined in the present paper.
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Insights into the phylogenetic and taxonomy of philasterid ciliates (Protozoa, Ciliophora, Scuticociliatia) based on analyses of multiple molecular markers.
Molecular Phylogenetics and Evolution, 2012Co-Authors: Laura A. Katz, Weibo SongAbstract:Scuticociliates are a rich assemblage of species with mostly unresolved phylogenetic relationships, especially in the order Philasterida. In the present work, 48 new sequences for three linked genes are characterized and phylogenetic trees are constructed to assess the inter- and intra-generic relationships of philasterids. Results reveal the following: (1) the combined three-gene tree provides more resolution in nodes than in the SSU-rDNA topologies; (2) the family Orchitophryidae is non-monophyletic as it is split into two parts and Paranophrys magna, Metanophrys sp. and Metanophrys sinensis are designated incertae sedis at the familial level; (3) Uronematidae is non-monophyletic and Homalogastra setosa is designated incertae sedis; (4) ParaUronematidae becomes a junior synonym of Uronematidae and the clade containing A. haemophila, Miamiensis avidus, and Glauconema trihymene might stand for a new family; (5) ParaUronema being a junior synonym of Uronema is supported and P. longum should be removed from the genus ParaUronema; (6) Uronema is not monophyletic and molecular analyses reveal that Uronema sp. QD shares a more recent common ancestor with Uronemella species than with other Uronema species; (7) Metanophrys is polyphyletic; (8) multiple samples of two highly controversial species, viz., Mesanophrys pugettensis and M. chesapeakensis have identical ITS1-5.8S-ITS2 region sequence and we propose they should be synonymous with M. carcini, and (9) there may be cryptic species in M. carcini and M. avidus.
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morphology and ssu rrna gene sequences of three marine ciliates from yellow sea china including one new species Uronema heteromarinum nov spec ciliophora scuticociliatida
Acta Protozoologica, 2010Co-Authors: J Huang, Xiaozhong Hu, Khaled A S Alrasheid, Weibo SongAbstract:The morphology, infraciliature, and silverline system of three marine scuticociliates, Uronema marinum Dujardin, 1841, U. heteromarinum nov. spec. and PleUronema setigerum Calkins, 1902, isolated from coastal waters off Qingdao, China, were investigated using living observation and silver impregnation methods. Due to the great confusion in the species definition of the well-known species U. marinum, we have documented a detailed discussion/comparison and believe that most of the confusion is due to the fact that at least 2 closely-related sibling morphotypes exist which are often not recognized. Based on the data available, U. marinum is strictly defined as follows: marine Uronema ca. 30 × 10 μm in size, with truncated apical frontal plate and smooth pellicle, extrusomes inconspicuous, cytostome located equatorially, 12-14 somatic kineties and one contractile vacuole pore near posterior end of kinety 2. Uronema heteromarinum nov. spec. resembles U. marinum but can be distinguished morphologically by its notched pellicle with conspicuous extrusomes and reticulate ridges, the 15-16 somatic kineties, widely separated membranelle 1 and membranelle 2, as well as the subequatorially positioned cytostome. Based on the Qingdao population, an improved diagnosis for the poorly known PleUronema setigerum is: marine slender oval-shaped form, in vivo about 40-50 x 15-20 μm; 3-5 preoral kineties and 14-22 somatic kineties; membranelle 1 and 3 three-rowed, and posterior end of M2a ring-like. The small subunit (SSU) rRNA gene for all three organisms were sequenced and analyzed with standard methods.
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Stomatogenesis of the marine ciliate Metanophrys sinensis (Protozoa: Ciliophora: Scuticociliatida)
Journal of the Marine Biological Association of the United Kingdom, 2003Co-Authors: Hongwei Ma, Weibo SongAbstract:Stomatogenesis of the marine scuticociliate Metanophrys sinensis, collected from a molluscan culturing pond in Qingdao, China, was studied using protargol impregnation mothod. The morphogenetic sequence develops in the proter: the remnant of parental paroral membrane gives rise to the paroral membrane and scutica, and the three parental membranelles were inherited. In the opisthe: the paroral membrane, membranelles 1, 2 and the scutica originate from the parental paroral membrane, while parental scutica gives rise to the membranelle 3. This suggests that M. sinensis has a relatively similar morphogenetic pattern to the members of the genus Uronema.
Alan Warren - One of the best experts on this subject based on the ideXlab platform.
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high density cultivation of the marine ciliate Uronema marinum ciliophora oligohymenophorea in axenic medium
Acta Protozoologica, 2015Co-Authors: Weibo Zheng, Alan WarrenAbstract:Uronema marinum is a cosmopolitan marine ciliate. It is a facultative parasite and the main causative agent of outbreaks of scuticociliatosis in aquaculture fish. This study reports a method for the axenic cultivation of U. marinum in high densities in an artificial medium comprising proteose peptone, glucose and yeast extract powder as its basic components. The absence of bacteria in the cultures was confirmed by fluorescence microscopy of DAPI-stained samples and the failure to recover bacterial SSU-rDNA using standard PCR methods. Using this axenic medium, a maximum cell density of 420,000 ciliate cells/ml was achieved, which is significantly higher than in cultures using living bacteria as food or in other axenic media reported previously. This method for high-density axenic cultivation of U. marinum should facilitate future research on this economically important facultative fish parasite.
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morphogenetic processes in division of Uronema filificum kahl 1931 ciliophora scuticociliatida and implications for its systematic position in the family Uronematidae
European Journal of Protistology, 1996Co-Authors: Blanca Perezuz, Weibo Song, Alan WarrenAbstract:Summary Stomatogenesis in Uronema filificum was studied with pyridinated silver carbonate. Fourteen morphogenetic stages are described. The ontogenetic sequence develops for the proter: haplokinety → haplokinety and scutica; for the opisthe: haplokinety → haplokinety, Ml, M2 and scutica, and scutica → M3. This stomatogenetic pattern is similar to that described for other genera in the same family, but the anlage morphogenetic sequence differs slightly from previous descriptions. The systematic position of Uronema filificum is discussed in the light of the new morphogenetic data reported.
Christos Katsaros - One of the best experts on this subject based on the ideXlab platform.
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comparative immunofluorescence and ultrastructural analysis of microtubule organization in Uronema sp klebsormidium flaccidum k subtilissimum stichococcus bacillaris and s chloranthus chlorophyta
Protist, 2011Co-Authors: Christos Katsaros, Vasilios Varvarigos, Claire M M Gachon, Jerry J Brand, Taizo Motomura, Chikako Nagasato, Frithjof C KupperAbstract:A detailed comparative examination of microtubule (MT) organization in interphase and dividing cells of Uronema sp. , Klebsormidium flaccidum , K. subtilissimum , Stichococcus bacillaris and S. chloranthus was made using tubulin immunofluorescence and transmission electron microscopy (TEM). During interphase all the species bear a well-organized cortical MT system, consisting of parallel bundles with different orientations. In Uronema sp. the cortical MT bundles are longitudinally oriented, whereas in the other species they are in transverse orientation to the axis of the cells. Considerable differences in MT organization were also observed during stages of mitosis, mainly preprophase, as well as cytokinesis. In Uronema sp. , a particular radial MT assembly is organized during preprophase-early prophase, which was not observed in the other species. In Stichococcus a fine MT ring surrounded the nucleus during preprophase and prophase. An MT ring, together with single cytoplasmic MTs, was also found associated with the developing diaphragm during cytokinesis in Stichococcus . A phycoplast participates in cytokinesis in Uronema sp., but not in the other species. In Uronema sp . the centrosome functions as a microtubule organizing center (MTOC) during mitosis, but not during interphase and cytokinesis. The phylogenetic significance of these differences is discussed in combination with SSU/ITS sequencing and other, existing molecular data.
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Comparative immunofluorescence and ultrastructural analysis of microtubule organization combined with SSU / ITS sequencing in Uronema sp., Klebsormidium flaccidum, K. subtilissimum, Stichococcus bacillaris and S. chloranthus (Chlorophyta)
Protist, 2011Co-Authors: Christos Katsaros, Vasilios Varvarigos, Claire M M Gachon, Taizo Motomura, Chikako Nagasato, Jery Brand, Frithjof C KupperAbstract:A detailed comparative examination of microtubule (MT) organization in interphase and dividing cells of Uronema sp. , Klebsormidium flaccidum , K. subtilissimum , Stichococcus bacillaris and S. chloranthus was made using tubulin immunofluorescence and transmission electron microscopy (TEM). During interphase all the species bear a well-organized cortical MT system, consisting of parallel bundles with different orientations. In Uronema sp. the cortical MT bundles are longitudinally oriented, whereas in the other species they are in transverse orientation to the axis of the cells. Considerable differences in MT organization were also observed during stages of mitosis, mainly preprophase, as well as cytokinesis. In Uronema sp. , a particular radial MT assembly is organized during preprophase-early prophase, which was not observed in the other species. In Stichococcus a fine MT ring surrounded the nucleus during preprophase and prophase. An MT ring, together with single cytoplasmic MTs, was also found associated with the developing diaphragm during cytokinesis in Stichococcus . A phycoplast participates in cytokinesis in Uronema sp., but not in the other species. In Uronema sp . the centrosome functions as a microtubule organizing center (MTOC) during mitosis, but not during interphase and cytokinesis. The phylogenetic significance of these differences is discussed in combination with SSU/ITS sequencing and other, existing molecular data.
Blanca Perezuz - One of the best experts on this subject based on the ideXlab platform.
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morphogenetic processes in division of Uronema filificum kahl 1931 ciliophora scuticociliatida and implications for its systematic position in the family Uronematidae
European Journal of Protistology, 1996Co-Authors: Blanca Perezuz, Weibo Song, Alan WarrenAbstract:Summary Stomatogenesis in Uronema filificum was studied with pyridinated silver carbonate. Fourteen morphogenetic stages are described. The ontogenetic sequence develops for the proter: haplokinety → haplokinety and scutica; for the opisthe: haplokinety → haplokinety, Ml, M2 and scutica, and scutica → M3. This stomatogenetic pattern is similar to that described for other genera in the same family, but the anlage morphogenetic sequence differs slightly from previous descriptions. The systematic position of Uronema filificum is discussed in the light of the new morphogenetic data reported.
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growth rate variability in geographically diverse clones of Uronema ciliophora scuticociliatida
FEMS Microbiology Ecology, 1995Co-Authors: Blanca PerezuzAbstract:Growth rates in 15 clones from the bacterivorous ciliate Uronema and one from ParaUronema acutum have been compared under similar culture conditions. Five species were identified on a morphological basis: U. marinum, U. nigricans, U. elegans, P. acutum, and an undescribed form designated here as SWi1. Intra- and inter-specific distinct growth characteristics were observed. Net cellular production tended to decrease with lower growth rate in different species or morphotypes but increased in those clones belonging to the same species. Growth rate and cell volume were not significatly correlated although mean growth rate increased with mean cell volume. Growth rate was however significantly correlated to the relative variation in cell volume between different growth phases. Estimation of growth rates using different models indicated that the experimental growth rates observed were not significatly different from those expected for the cell volumes. These results indicate how effects of habitat or geographical variability, in this cosmopolitan genus, may account for trophodynamic variation of morphologically similar species.
