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Tatsuomi Matsuoka - One of the best experts on this subject based on the ideXlab platform.
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early signaling pathways mediating dormant cyst formation in terrestrial unicellular eukaryote Colpoda
Fems Microbiology Letters, 2021Co-Authors: Tatsuomi MatsuokaAbstract:Dormant (resting) cyst formation (encystment) in unicellular eukaryotes is the process of a large-scale digestion of vegetative cell structures and reconstruction into the dormant form, which is performed by cell signaling pathways accompanied by up- or down-regulation of protein expression, and by posttranslational modification such as phosphorylation. In this review, the author describes the morphogenetic events during encystment of Colpoda and the early molecular events in the Ca2+/calmodulin-triggered signaling pathways for encystment, based mainly on our research results of the past 10 years; especially, the author discusses the role of c-AMP dependently phosphorylated proteins (ribosomal P0 protein, ribosomal S5 protein, Rieske iron-sulfur protein, actin and histone H4) and encystment-dependently upregulated (EF-1α-HSP60, actin-related protein) and downregulated proteins (ATP synthase β-chain). In addition, the roles of AMPK, a key molecule in the signaling pathways leading to Colpoda encystment, and differentially expressed genes and proteins during encystment of other ciliates are discussed.
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molecular events during resting cyst formation in unicellular eukaryote Colpoda
Biomedical Journal of Scientific and Technical Research, 2019Co-Authors: Tatsuomi MatsuokaAbstract:One strategy of some pathogenic unicellular eukaryotes is to form resting cysts that are resistant to the environmental stresses of the host, such as stomach acid or immune system attack...
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photoresponse in the ciliated protozoan Colpoda cucullus
Acta Protozoologica, 2017Co-Authors: Noriyuki Kawano, Ryoji Funadani, Futoshi Suizu, Mikihiko Arikawa, Tetsuo Harada, Kou Matsuoka, Tatsuomi MatsuokaAbstract:We found that vegetative cells of Colpoda cucullus Nag-1 accumulated in shaded areas of a container when grown in the laboratory and then formed resting cysts. The photodispersal (negative photoaccumulation) of C. cucullus was mediated, at least in part, by a difference in forward swimming velocity between the illuminated region and the shaded area of the Petri dish (motion slowed or stopped in the shaded area). When C. cucullus was stimulated by continuous light irradiation, the forward swimming velocity increased and reached a steady state within 10 s. When the light intensity decreased, the forward swimming velocity gradually decreased, and eventually returned to its original level for approximately 1 min. The action spectrum of the photokinetic response (steady-state swimming acceleration driven by continuous light stimulation) implies the involvement of blue light receptors.
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ef 1α silencing by feeding rnai suppresses resting cyst formation in Colpoda cucullus nag 1 strain
ISJ-Invertebrate Survival Journal, 2016Co-Authors: Yoichiro Sogame, M Hori, Tatsuomi MatsuokaAbstract:It is reported that the expression level of EF-1α in Colpoda cucullus Nag-1 is markedly enhanced within several hours after the onset of encystment induction. In this study, the Colpoda strain (stock EQ-1) known to promptly encyst also showed early EF-1α expression while the strain (stock ES-1) known to show prolonged encystment also showed delayed EF-1α expression. In cells in which EF-1α is silenced by feeding RNAi, the cyst formation was prolonged, but normal cyst walls were formed. These results suggest that Colpoda EF-1α is involved in the early morphogenetic events of the resting cyst formation by accelerating protein translation or cytosleletal dynamics such as microtubule disintegration.
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Morphological study on the encystment of the ciliated protozoan Colpoda cucullus
2015Co-Authors: Tomoko Watoh, Akemi Kida, Keisuke Yamamoto, Satoko Sekida, Tatsuomi MatsuokaAbstract:Morphological changes during resting cyst formation (encystment) of Colpoda cucullus were examined. At 1 hr after encystment induction, a number of vesicles containing the electron-dense and toluidine blue (TB) positive materials were fused with large vacuoles to excrete the contents, and the vacuoles opened to the extracellular space to excrete. In this stage, the rounded precystic cells were surrounded by the first-synthesized cyst wall layer (L1 layer), and the cilia were resorbed inside the L1 layer. Thereafter (1-2 hr), a secondary layer (L2 layer) was formed and subsequently a deeply TB stained substance was diffused into the space between the plasma membrane and L2 layer. At 3-6 hr, numerous endoplasmic reticula (ER) associated with ribosomes occupied the cytoplasm, indicating that cyst wall precursors such as glycoconjugates were being synthesized. By a week after encystment induction, the cyst wall composed of three distinct layers covered with a fibrous (mucous) coat was completed. The kinetosomes were still observed in 3-day old cysts
Juan Carlos Gutiérrez - One of the best experts on this subject based on the ideXlab platform.
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evaluation of heavy metal acute toxicity and bioaccumulation in soil ciliated protozoa
Environment International, 2006Co-Authors: Silvia Diaz, Ana Martingonzalez, Juan Carlos GutiérrezAbstract:Laboratory toxicity tests, using ciliated protozoa, are scarce and they have been carried out usually with freshwater species. In this study, we have analysed the acute cytotoxicity of Cd, Zn and Cu in five different strains of very common soil ciliate species (Colpoda steinii, Colpoda inflata and Cyrtolophosis elongata), which were isolated from very different soil samples (polluted or not with heavy metals). Soil ciliates are quite resistant to heavy metals pollution with regard to ciliates from other habitats. The toxicity sequence was Cd>Cu>>Zn. Results from Cd+Zn mixtures indicated that Cd cytotoxicity decreases in the presence of low or moderate Zn concentrations. A broad heavy metal resistance level diversity exists among isolates of colpodid ciliates and it is seen to be a genetic feature rather than a habitat dependence. Bioaccumulation is seen to be the main mechanism involved in the metal resistance, except for Cu. For the first time in ciliates, a fluorescent method has been applied to detect Zn intracellular deposits. This methodology might be an useful tool for monitoring heavy metal pollution in soils.
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macronuclear chromatin changes during encystment in the ciliate Colpoda inflata formation of crystal like structures in the resting cyst chromatin and nucleolar condensation
European Journal of Protistology, 2001Co-Authors: Ana Martingonzalez, Gemma Palacios, Juan Carlos GutiérrezAbstract:We analysed the macronuclear chromatin structure changes during encystment of the ciliate Colpoda inflata, using both standard transmission electron microscopy and a spreading chromatin method, from isolated vegetative and resting cyst macronuclei. The vegetative macronucleus of C. inflata, like the majority of ciliates, is formed by discrete condensed chromatin clumps, which became fused during encystment. In mature resting cysts the macronuclear chromatin was similar to vegetative or resting cyst micronuclear chromatin probably indicating the transcriptional inactivity of the macronucleus in this stage. Likewise, the numerous nucleolar masses of the vegetative stage fused in only one nucleolar body during resting cyst formation, and in this nucleolar mass neither a granular zone nor nucleolar organizers were observed. Hybridization with a ribosomal DNA probe, after pulsed field gel electrophoresis of vegetative and mature resting cysts, showed that ribosomal DNA molecules could be compacted with some nucleolar elements, corroborating the nucleolar inactivation inferred from the ultrastructural data. The chromatin spreading method has revealed that vegetative macronuclear chromatin is formed by a net of long fibres organized in polynemic cords probably representing amplified regions of the macronuclear genome. It represents, as in the colpodid ciliate Bursaria, a type of non-classical polyteny. In this study we report for the first time in the genus Colpoda, a very special structural organization of the macronuclear chromatin in mature resting cysts: the existence of crystal-like hexagonal bodies. We also discuss widely all these macronuclear chromatin modifications and the factors that could be involved in the formation of polygonal structures.
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DNA methylation in ciliates: implications in differentiation processes.
International microbiology : the official journal of the Spanish Society for Microbiology, 2000Co-Authors: Juan Carlos Gutiérrez, Sergio Callejas, Sara Borniquel, Ana Martín-gonzálezAbstract:Much experimental evidence on the role of DNA methylation in gene expression has been reported. Here we review reports on DNA methylation in ciliated protozoa, emphasizing its implications in cell differentiation processes. Both types of methylated bases (adenine and cytosine) can be found in macronuclear DNA. The division cycle and conjugation have been studied with regard to adenine methylation, and several different functions have been assigned to the methylation changes detected in these processes. Cytosine methylation changes were analyzed during stomatogenesis of Paramecium and encystment of Colpoda inflata. A comparative analysis with other similar microbial eukaryotic differentiation processes is carried out.
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Encystment-specific mRNA is accumulated in the resting cysts of the ciliate Colpoda inflata.
Iubmb Life, 1997Co-Authors: Laura Benítez, Juan Carlos GutiérrezAbstract:From a random amplified polymorphism cDNA study using vegetative, precystic and mature resting cysts of the ciliate Colpoda inflata, a stage-specific fragment was isolated from the resting cyst cDNA population. This fragment was used as an encystment probe to study the corresponding mRNA expression during this eukaryotic cell differentiation process. This transcript is accumulated in the resting cyst of this ciliate, and it is the first time that accumulation of specific mRNA molecules associated with the ciliate cryptobiosis process is reported. The meaning of this stored mRNA in microbial cryptobiotic stages is discussed.
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macronuclear dna demethylation is involved in the encystment process of the ciliate Colpoda inflata
Cell Biology International, 1994Co-Authors: Gemma Palacios, Ana Martingonzalez, Juan Carlos GutiérrezAbstract:Ciliate encystment is an eukaryotic cell differentiation process which involves a specific gene expression, to form the resting stage. In this study, we investigate, for first time, the DNA methylation pattern changes during encystment in the ciliate Colpoda inflata, and the 5-azacytidine effect on growing cells and encystment. Results indicate that 5-methylcytosine is present in macronuclear DNA of this ciliate and the 5-azacytidine treatment induces encystment in growth conditions. From restriction enzyme digestion and 5-azacytidine experiments, we conclude that a specific DNA demethylation is probably involved in the encystment gene expression of this ciliate.
Yoichiro Sogame - One of the best experts on this subject based on the ideXlab platform.
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evidence of stress recovery in free living ciliate Colpoda cucullus the repair capability of resting cysts to damage caused by gamma irradiation
Acta Protozoologica, 2019Co-Authors: Yoichiro Sogame, Ryota Saito, Ryota Koizumi, Taiga Shimizu, Taiki OnoAbstract:Evidence of Stress Recovery in Free-Living Ciliate Colpoda cucullus: The Repair Capability of Resting Cysts to Damage Caused by Gamma Irradiation
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morphogenetic and molecular analyses of cyst wall components in the ciliated protozoan Colpoda cucullus nag 1
Fems Microbiology Letters, 2016Co-Authors: Ryoji Funadani, Yoichiro Sogame, Toshikazu Takeshita, Katsuhiko Kojima, Seiji Miyata, Keisuke Yamamoto, Tomoya Tsujizono, Futoshi Suizu, Kenichi Yagyu, Tomohiko SuzukiAbstract:The cyst wall of the resting cyst of the ciliated protozoan Colpoda cucullus (Nag-1 strain) is composed of several layers of endocyst, a single layer of ectocyst associated with a mucous layer and lepidosomes composed of a fibrous or crystal-like structure. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis showed that the ectocyst associated with lepidosomes and mucous materials contained proteins corresponding to 27, 31, 45 kDa and smear bands ranging from 50 to 60 kDa. Liquid chromatography-tandem mass spectrometry of these proteins revealed that the 45-kDa protein (p45) was elongation factor Tu (EF-Tu). Immunofluorescence microscopy with an anti-EF-Tu polyclonal antibody showed that Colpoda EF-Tu (p45) was localized in the lepidosomes. The lepidosomes were stained vividly with Congo red, which is bound to the stacked β-sheets of amyloid protofibrils. In the presence of puromycin, no cyst wall components including lepidosomes were formed, indicating that cyst wall formation requires synthesis of proteins including EF-Tu. Electron microscopy of encysting cells implied that vesicles which were presumably budded from endoplasmic reticula possibly fuse with a lepidosome-precursor vacuole containing electron-dense fine particles or fibrous structures, and followed by the subsequent fusion with other electron-lucent granules.
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ef 1α silencing by feeding rnai suppresses resting cyst formation in Colpoda cucullus nag 1 strain
ISJ-Invertebrate Survival Journal, 2016Co-Authors: Yoichiro Sogame, M Hori, Tatsuomi MatsuokaAbstract:It is reported that the expression level of EF-1α in Colpoda cucullus Nag-1 is markedly enhanced within several hours after the onset of encystment induction. In this study, the Colpoda strain (stock EQ-1) known to promptly encyst also showed early EF-1α expression while the strain (stock ES-1) known to show prolonged encystment also showed delayed EF-1α expression. In cells in which EF-1α is silenced by feeding RNAi, the cyst formation was prolonged, but normal cyst walls were formed. These results suggest that Colpoda EF-1α is involved in the early morphogenetic events of the resting cyst formation by accelerating protein translation or cytosleletal dynamics such as microtubule disintegration.
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Identification of cAMP-dependent phosphorylated proteins involved in the formation of environment-resistant resting cysts by the terrestrial ciliate Colpoda cucullus
ISJ-Invertebrate Survival Journal, 2014Co-Authors: Yoichiro Sogame, Toshikazu Takeshita, Katsuhiko Kojima, Eiji Kinoshita, Tatsuomi MatsuokaAbstract:In the terrestrial ciliate Colpoda cucullus, an elevation of the intracellular cAMP concentration was reported to be involved in environment-resistant resting cyst formation. In the present study, cAMP-dependently phosphorylated proteins of encystment-induced C. cucullus were isolated with Phos-tag agarose phosphate-affinity beads and subsequent SDS-PAGE. In a liquid chromatography/tandem mass spectrometry analysis of these phosphoproteins, 27-, 37- and 43-kDa proteins (p27, p37 and p43) were identified as Rieske iron-sulfur protein, histone H4 (hyperacetylated form), and actin, respectively.
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Identification of differentially expressed water-insoluble proteins in the encystment process of Colpoda cucullus by two-dimensional electrophoresis and LC-MS/MS analysis.
Journal of Eukaryotic Microbiology, 2013Co-Authors: Yoichiro Sogame, Toshikazu Takeshita, Katsuhiko Kojima, Eiji Kinoshita, Tatsuomi MatsuokaAbstract:In the encystment process of the ciliate protist Colpoda cucullus, we observed that the cell total protein abundance was reduced at 12 h–1 d after the onset of encystment induction subsequent to the reduction in mRNA abundance. We analyzed the alteration of the expression levels of water-insoluble proteins by two-dimensional polyacrylamide gel electrophoresis using polyoxyethylene (20) sorbitan monooleate (Tween-80), and we identified proteins whose expression levels were altered in the encystment process by a liquid chromatography tandem mass spectrometry analysis. The expression level of a 60-kDa protein (p60; heat shock protein 60) was temporarily enhanced and that of a 55-kDa protein (p55; actin) and a 49-kDa protein (p49; actin) was enhanced in the Colpoda encystment process. In mature cysts, the expression level of p55 and p49 tended to be reduced, whereas the expression level of a 50-kDa protein (p50d; α-tubulin), a 25-kDa protein (p25; α-tubulin) and a 52-kDa protein (p52c; β-tubulin) was enhanced.
Wilhelm Foissner - One of the best experts on this subject based on the ideXlab platform.
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molecular phylogenetic analysis of class colpodea phylum ciliophora using broad taxon sampling
Molecular Phylogenetics and Evolution, 2008Co-Authors: Micah Dunthorn, Wilhelm Foissner, Laura A KatzAbstract:The ciliate class Colpodea provides a powerful case in which a molecular genealogy can be compared to a detailed morphological taxonomy of a microbial group. Previous analyses of the class using the small-subunit rDNA are based on sparse taxon sampling, and are therefore of limited use in comparisons with morphologically-based classifications. Taxon sampling is increased here to include all orders within the class, and more species within previously sampled orders and in the species rich genus Colpoda. Results indicate that the Colpodea may be paraphyletic, although there is no support for deep nodes. The orders Bursariomorphida, Grossglockneriida, and Sorogenida are monophyletic. The orders Bryometopida, Colpodida, and Cyrtolophosidida, and the genus Colpoda, are not monophyletic. Although congruent in many aspects, the conflict between some nodes on this single gene genealogy and morphology-based taxonomy suggests the need for additional markers as well as a reassessment of the Colpodea taxonomy.
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pseudomaryna australiensis nov gen nov spec and Colpoda brasiliensis nov spec two new colpodids ciliophora colpodea with a mineral envelope
European Journal of Protistology, 2003Co-Authors: Wilhelm FoissnerAbstract:Pseudomaryna australiensis and Colpoda brasiliensis were discovered in floodplain soils from Australia and Brazil and studied in vivo and in silver preparations. They have a common feature, viz., a sheath of clay (mineral) particles embedded in a slimy matrix. Such sheaths, which evolved convergently in various ciliates, are termed “mineral envelopes” and make cells appear like inorganic soil particles, possibly protecting them from predators. The new genus Pseudomaryna belongs to the family Colpodidae and is characterized by the preoral suture which extends for the whole body length right of the oral opening due to the widely projecting left side ciliary rows. Maryna antarctica Foissner, 1993 has the same ciliary pattern and is thus transferred to the new genus: Pseudomaryna antarctica (Foissner, 1993) nov. comb. Both, P. australiensis and P. antarctica are small (length 25–60 μm), reniform soil ciliates differing in the macronuclear structure (with vs. without central nucleolus), the mineral envelope (present vs. absent), and details of the somatic and oral ciliary pattern. Colpoda brasiliensis is also a small ciliate (about 33 × 18 μm), differing from the congeners by the mineral envelope and a combination of ordinary features, viz., the location and structure of the macronucleus and the preoral ciliary pattern. Probably, it is related to the Colpoda steinii group.
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phylogenetic relationships of orders within the class colpodea phylum ciliophora inferred from small subunit rrna gene sequences
Journal of Molecular Evolution, 1999Co-Authors: Denis H Lynn, Martin Schlegel, Andredenis G Wright, Wilhelm FoissnerAbstract:Molecular analyses have been used recently to refine our knowledge of phylogenetic relationships within the ciliated protozoa (phylum Ciliophora). A current Hennigian phylogeny of the orders in the class Colpodea, based on light and electron microscopic analyses, makes three important assumptions with regard to apomorphic character states, namely, (1) that the kreyellid silver line evolved early in colpodean phylogeny, separating bryometopids, such as Bryometopus, from all other colpodeans; (2) that the macro–micronuclear complex is an autapomorphy of the cyrtolophosidids, such as Platyophrya; and (3) that merotelokinetal stomatogenesis is an apomorphic character of colpodids, such as Colpoda, Bresslaua, and Pseudoplatyophrya. These predictions of relationships within the class Colpodea were investigated by determining the complete small subunit rRNA gene sequences for the colpodid Bresslaua vorax, the grossglockneriid Pseudoplatyophrya nana, and the cyrtolophosidid Platyophrya vorax and a partial sequence for the bryometopid Bryometopus sphagni. These sequences were combined with the previously published complete SSrRNA sequences for the colpodid Colpoda inflata and the bursariomorphid Bursaria truncatella. The affiliations were assessed using both distance matrix and maximum-parsimony analyses. The tree topologies for the class Colpodea were identical in all analyses, with bootstrap support for bifurcations always exceeding 60%. The results suggest the following. (1) Since the clade including Bryometopus and its sister taxon, Bursaria, is never basal, the kreyellid silver-line system evolved later in colpodean phylogeny and does not separate bryometopids from all other colpodeans. (2) Since Platyophrya is always the sister taxon to the other five genera, there is a fundamental phylogenetic significance for its macro–micronuclear complex. (3) Since the colpodids, Colpoda, Bresslaua, and Pseudoplatyophrya, always group in one clade, merotelokinetal stomatogenesis appears to be a derived character state.
Denis H Lynn - One of the best experts on this subject based on the ideXlab platform.
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phylogenetic relationships of orders within the class colpodea phylum ciliophora inferred from small subunit rrna gene sequences
Journal of Molecular Evolution, 1999Co-Authors: Denis H Lynn, Martin Schlegel, Andredenis G Wright, Wilhelm FoissnerAbstract:Molecular analyses have been used recently to refine our knowledge of phylogenetic relationships within the ciliated protozoa (phylum Ciliophora). A current Hennigian phylogeny of the orders in the class Colpodea, based on light and electron microscopic analyses, makes three important assumptions with regard to apomorphic character states, namely, (1) that the kreyellid silver line evolved early in colpodean phylogeny, separating bryometopids, such as Bryometopus, from all other colpodeans; (2) that the macro–micronuclear complex is an autapomorphy of the cyrtolophosidids, such as Platyophrya; and (3) that merotelokinetal stomatogenesis is an apomorphic character of colpodids, such as Colpoda, Bresslaua, and Pseudoplatyophrya. These predictions of relationships within the class Colpodea were investigated by determining the complete small subunit rRNA gene sequences for the colpodid Bresslaua vorax, the grossglockneriid Pseudoplatyophrya nana, and the cyrtolophosidid Platyophrya vorax and a partial sequence for the bryometopid Bryometopus sphagni. These sequences were combined with the previously published complete SSrRNA sequences for the colpodid Colpoda inflata and the bursariomorphid Bursaria truncatella. The affiliations were assessed using both distance matrix and maximum-parsimony analyses. The tree topologies for the class Colpodea were identical in all analyses, with bootstrap support for bifurcations always exceeding 60%. The results suggest the following. (1) Since the clade including Bryometopus and its sister taxon, Bursaria, is never basal, the kreyellid silver-line system evolved later in colpodean phylogeny and does not separate bryometopids from all other colpodeans. (2) Since Platyophrya is always the sister taxon to the other five genera, there is a fundamental phylogenetic significance for its macro–micronuclear complex. (3) Since the colpodids, Colpoda, Bresslaua, and Pseudoplatyophrya, always group in one clade, merotelokinetal stomatogenesis appears to be a derived character state.
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phylogenetic relationships of blepharisma americanum and Colpoda inflata within the phylum ciliophora inferred from complete small subunit rrna gene sequences
Journal of Eukaryotic Microbiology, 1991Co-Authors: Spencer J Greenwood, Martin Schlegel, Mitchell L Sogin, Denis H LynnAbstract:The complete small subunit rRNA gene sequences of the heterotrich Blepharisma americanum and the colpodid Colpoda inflata were determined to be 1719 and 1786 nucleotides respectively. the phylogeny produced by comparisons with other ciliates indicated that C. inflata is allied more closely with the nassophoreans and oligohymenophoreans than the spirotrichs. This is consistent with the placement of the colpodids in the Class Copodea. Blepharisma americanum was not grouped with the hypotrichs but instead was placed as the earliest branching ciliate. the distinct separation of B. americanum supports the elevation to class status given the heterotrichs based on morphological characters.