Artículos de revistas: "Paramecium"

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Potekhin, Alexey y Rosaura Mayén-Estrada. "Paramecium Diversity and a New Member of the Paramecium aurelia Species Complex Described from Mexico". Diversity 12, n.º 5 (15 de mayo de 2020): 197. http://dx.doi.org/10.3390/d12050197.

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Paramecium (Ciliophora) is an ideal model organism to study the biogeography of protists. However, many regions of the world, such as Central America, are still neglected in understanding Paramecium diversity. We combined morphological and molecular approaches to identify paramecia isolated from more than 130 samples collected from different waterbodies in several states of Mexico. We found representatives of six Paramecium morphospecies, including the rare species Paramecium jenningsi, and Paramecium putrinum, which is the first report of this species in tropical regions. We also retrieved five species of the Paramecium aurelia complex, and describe one new member of the complex, Paramecium quindecaurelia n. sp., which appears to be a sister species of Paramecium biaurelia. We discuss criteria currently applied for differentiating between sibling species in Paramecium. Additionally, we detected diverse bacterial symbionts in some of the collected ciliates.

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Bator, Tomasz. "A New Laboratory Cultivation of Paramecium bursaria Using Non-Pathogenic Bacteria Strains". Zeitschrift für Naturforschung C 65, n.º 7-8 (1 de agosto de 2010): 479–82. http://dx.doi.org/10.1515/znc-2010-7-810.

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In most studies dealing with the laboratory cultivation of paramecia (Paramecium bursaria), Klebsiella pneumoniae bacteria are used to inoculate the medium. However, Klebsiella pneumoniae is a typical pathogen, and its use is always associated with a risk of infection. The aim of the present research was to examine non-pathogenic bacteria strains as components of the medium for Paramecium bursaria. The paramecia were incubated on lettuce infusions bacterized with different bacteria strains: Bacillus subtilis DSM 10, Bacillus megaterium DSM 32, Escherichia coli DSM 498, Micrococcus luteus DSM 348. A strain derived from the natural habitat of Paramecium bursaria was used as the control one. Experiments were conducted under constant light and in the dark. Paramecia cells were counted under a stereomicroscope on consecutive days of incubation. The obtained results show that the most intensive growth of Paramecium bursaria occurs in the presence of Escherichia coli DSM 498. The use of this strain as a component of the medium allows one to obtain a high number of ciliates regardless of the light conditions. It can be concluded that the Paramecium bursaria cultivation procedure can be modified by using the non-pathogenic bacteria strain Escherichia coli DSM 498 instead of Klebsiella pneumoniae.

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Kawano, Tomonori, Takashi Kadono, Toshikazu Kosaka y Hiroshi Hosoya. "Green Paramecia as an Evolutionary Winner of Oxidative Symbiosis: A Hypothesis and Supportive Data". Zeitschrift für Naturforschung C 59, n.º 7-8 (1 de agosto de 2004): 538–42. http://dx.doi.org/10.1515/znc-2004-7-816.

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AbstractA single cell of the green paramecia (Paramecium bursaria) harbors several hundreds of endo-symbiotic Chlorella-like algae in its cytoplasm. Removal of algae from the host organism and re-association of ex-symbiotic host paramecia with ex-symbiotic algae can be experimentally demonstrated in the laboratory. However, the mechanism precisely governing the alga-protozoan association is not fully understood, and the origin of symbiosis in the evolutionary view has not been given. Here, we propose the possible biochemical models (models 1 and 2) explaining the co-evolution between Paramecium species and algal symbionts by pointing out that algal photosynthesis in the host paramecia plays a dual role providing the energy source and the risk of oxidative damage to the host. Model 1 lays stress on the correlation between the (re)greening ability of the paramecia and the tolerance to oxidative stress whereas model 2 emphasizes the cause of evolutionary selection leading to the emergence of Paramecium species tolerant against reactive oxygen species.

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4

Otsuka, Kohei, Sayaka Maruta, Atsuko Noriyasu, Kohji Nakazawa y Tomonori Kawano. "Single Cell Traffic of Swimming Green Paramecia on Microchips with Micro-Flow Channels Fabricated by Micro-Casting". Advanced Materials Research 875-877 (febrero de 2014): 2224–28. http://dx.doi.org/10.4028/www.scientific.net/amr.875-877.2224.

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Members of Paramecium species are often referred to as “swimming neurons or sensory cells” applicable to micro-biorobotics or BioMEMS (biological micro-electro-mechanical systems). Paramecium bursaria known as green paramecia is an unicellular organism that lives widely in fresh water environments such as rivers and ponds. Recent studies have suggested that in vivo cellular robotics using the living cells of green paramecia as micro-machines controllable under electrical, optical and magnetic signals, has a variety of engineering applications such as transportation of micro-sized particles (ingested within the cells) in the capillary systems. In the present study, we aimed to test if the swimming environment of green paramecia can be implementable on microchips. For this purpose, the series of microchips were prepared for cellular swimming platform for green paramecia through fabrication of poly(methyl methacrylate) master plates using the programmable micro-milling system followed by polydimethylsiloxane-based micro-casting. Finally, microchips equipped with optimally sized micro-flow channels for allowing the single cell traffic by swimming green paramecia were successfully prepared, and thus further studies for application of green paramecium cells in BioMEMS are encouraged.

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5

Bator, Tomasz y Ryszard Pado. "The Infl uence of Hypergravity on the Paramecium bursaria- Chlorella sp. Symbiotic Association". Zeitschrift für Naturforschung C 64, n.º 9-10 (1 de octubre de 2009): 743–46. http://dx.doi.org/10.1515/znc-2009-9-1021.

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The aim of the research was to determine the influence of strong hypergravity on the Paramecium bursaria-Chlorella sp. symbiotic association, which is considered to be a model example of symbiosis between a heterotroph and an autotroph. The paramecia cells were exposed to 1073 × g, 4293 × g, and 9658 × g hypergravity for 15 min. Then they were incubated for 21 d on a standard lettuce medium. The experiments were conducted in parallel under constant white light and in the dark. The changes in the number of paramecia cells during incubation were determined. Measurements of the number of Chlorella sp. endosymbionts inside host cells were also made. The results showed that a 15-min exposure to hypergravity attenuates the subsequent growth of Paramecium bursaria in the dark, but it may stimulate the growth of paramecia under constant light. Moreover, it causes an increase in the number of algae inside the paramecia cells. Presumably, the influence of hypergravity on the studied symbiotic complex is connected with its effect on the endosymbiotic Chlorella sp. cells. This subject requires further research, focused on the influence of hypergravity on the physiology and growth of the Chlorella sp. endosymbionts living inside the Paramecium bursaria cells

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6

Elices, Irene, Anirudh Kulkarni, Nicolas Escoubet, Léa-Laetitia Pontani, Alexis Michel Prevost y Romain Brette. "An electrophysiological and kinematic model of Paramecium, the “swimming neuron”". PLOS Computational Biology 19, n.º 2 (9 de febrero de 2023): e1010899. http://dx.doi.org/10.1371/journal.pcbi.1010899.

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Paramecium is a large unicellular organism that swims in fresh water using cilia. When stimulated by various means (mechanically, chemically, optically, thermally), it often swims backward then turns and swims forward again in a new direction: this is called the avoiding reaction. This reaction is triggered by a calcium-based action potential. For this reason, several authors have called Paramecium the “swimming neuron”. Here we present an empirically constrained model of its action potential based on electrophysiology experiments on live immobilized paramecia, together with simultaneous measurement of ciliary beating using particle image velocimetry. Using these measurements and additional behavioral measurements of free swimming, we extend the electrophysiological model by coupling calcium concentration to kinematic parameters, turning it into a swimming model. In this way, we obtain a model of autonomously behaving Paramecium. Finally, we demonstrate how the modeled organism interacts with an environment, can follow gradients and display collective behavior. This work provides a modeling basis for investigating the physiological basis of autonomous behavior of Paramecium in ecological environments.

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Aonuma, Miki, Takashi Kadono y Tomonori Kawano. "Inhibition of Anodic Galvanotaxis of Green Paramecia by T-Type Calcium Channel Inhibitors". Zeitschrift für Naturforschung C 62, n.º 1-2 (1 de febrero de 2007): 93–102. http://dx.doi.org/10.1515/znc-2007-1-217.

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Calcium ion (Ca2+) is one of the key regulatory elements for ciliary movements in the Paramecium species. It has long been known that members of Paramecium species including green paramecia (Paramecium bursaria) exhibit galvanotaxis which is the directed movement of cells toward the anode by swimming induced in response to an applied voltage. However, our knowledge on the mode of Ca2+ action during green paramecia anodic galvanotactic response is still largely limited. In the present study, quantification of anodic galvanotaxis was carried out in the presence and absence of various inhibitors of calcium signaling and calcium channels. Interestingly, galvanotactic movement of the cells was completely inhibited by a variety of Ca2+-related inhibitors. Such inhibitors include a Ca2+ chelator (EGTA), general calcium channel blockers (such as lanthanides), inhibitors of intracellular Ca2+ release (such as ruthenium red and neomycin), and inhibitors of T-type calcium channels (such as NNC 55-0396, 1-octanol and Ni2+). However, L-type calcium channel inhibitors such as nimodipine, nifedipine, verapamil, diltiazem and Cd2+ showed no inhibitory action. This may be the first implication for the involvement of T-type calcium channels in protozoan cellular movements.

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8

Yakovleva, Yulia, Elena Nassonova, Natalia Lebedeva, Olivia Lanzoni, Giulio Petroni, Alexey Potekhin y Elena Sabaneyeva. "The first case of microsporidiosis in Paramecium". Parasitology 147, n.º 9 (27 de abril de 2020): 957–71. http://dx.doi.org/10.1017/s0031182020000633.

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AbstractA new microsporidian species, Globosporidium paramecii gen. nov., sp. nov., from Paramecium primaurelia is described on the basis of morphology, fine structure, and SSU rRNA gene sequence. This is the first case of microsporidiosis in Paramecium reported so far. All observed stages of the life cycle are monokaryotic. The parasites develop in the cytoplasm, at least some part of the population in endoplasmic reticulum and its derivates. Meronts divide by binary fission. Sporogonial plasmodium divides by rosette-like budding. Early sporoblasts demonstrate a well-developed exospore forming blister-like structures. Spores with distinctive spherical shape are dimorphic in size (3.7 ± 0.2 and 1.9 ± 0.2 μm). Both types of spores are characterized by a thin endospore, a short isofilar polar tube making one incomplete coil, a bipartite polaroplast, and a large posterior vacuole. Experimental infection was successful for 5 of 10 tested strains of the Paramecium aurelia species complex. All susceptible strains belong to closely related P. primaurelia and P. pentaurelia species. Phylogenetic analysis placed the new species in the Clade 4 of Microsporidia and revealed its close relationship to Euplotespora binucleata (a microsporidium from the ciliate Euplotes woodruffi), to Helmichia lacustris and Mrazekia macrocyclopis, microsporidia from aquatic invertebrates.

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9

Otter, T. y E. D. Salmon. "Pressure-induced changes in Ca2+-channel excitability in Paramecium". Journal of Experimental Biology 117, n.º 1 (1 de julio de 1985): 29–43. http://dx.doi.org/10.1242/jeb.117.1.29.

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The behaviour of swimming Paramecium is markedly affected by hydrostatic pressure (50–200 atm, 1 atm = 101 325 Pa). To investigate whether pressure might alter behaviour by acting directly on specific ion channels that mediate the behavioural responses, we examined the effects of K+, Na+ and Ba2+ ions on swimming speed and the reversal response during pressurization and decompression. If pressure acted on the channels that transport these ions, then the pressure-induced responses of swimming Paramecium should be exaggerated or diminished, according to which ions were present in the experimental buffer. Pressurization to 100 atm in standard buffer inhibited the brief reversal of swimming direction that occurred at atmospheric pressure when a paramecium encountered the wall of the pressure chamber. To determine whether pressure impaired mechanoreceptor function or directly blocked the Ca2+-channels that control ciliary reversal, we added Ba2+ or Na+ to standard buffer to induce multiple spontaneous reversals. Pressurization blocked these reversals, suggesting that channel opening is directly inhibited by pressure. Decompression in standard buffer elicited momentary ciliary reversal and backward swimming. Buffers with a high ratio of K+ to Ca2+ suppressed this response, and the decompression-induced reversal was exaggerated in the presence of Ba2+ or Na+, consistent with the effects that these ions are known to have on Paramecium's reversal response. These data imply that, upon decompression, the Ca2+-channels that mediate ciliary reversal open transiently. In addition to blocking the reversal response, pressurization slowed forward swimming. By examining the response to pressurization of Paramecium immobilized by Ni2+, we found that hydrostatic pressure apparently slows swimming by reorientating the direction of ciliary beat.

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10

Melekhin, Maksim, Yulia Yakovleva, Natalia Lebedeva, Irina Nekrasova, Liubov Nikitashina, Michele Castelli, Rosaura Mayén-Estrada, Anna E. Romanovich, Giulio Petroni y Alexey Potekhin. "Cryptic Diversity in Paramecium multimicronucleatum Revealed with a Polyphasic Approach". Microorganisms 10, n.º 5 (5 de mayo de 2022): 974. http://dx.doi.org/10.3390/microorganisms10050974.

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Paramecium (Ciliophora) systematics is well studied, and about twenty morphological species have been described. The morphological species may include several genetic species. However, molecular phylogenetic analyses revealed that the species diversity within Paramecium could be even higher and has raised a problem of cryptic species whose statuses remain uncertain. In the present study, we provide the morphological and molecular characterization of two novel Paramecium species. While Paramecium lynni n. sp., although morphologically similar to P. multimicronucleatum, is phylogenetically well separated from all other Paramecium species, Paramecium fokini n. sp. appears to be a cryptic sister species to P. multimicronucleatum. The latter two species can be distinguished only by molecular methods. The number and structure of micronuclei, traditionally utilized to discriminate species in Paramecium, vary not only between but also within each of the three studied species and, thus, cannot be considered a reliable feature for species identification. The geographic distribution of the P. multimicronucleatum and P. fokini n. sp. strains do not show defined patterns, still leaving space for a role of the geographic factor in initial speciation in Paramecium. Future findings of new Paramecium species can be predicted from the molecular data, while morphological characteristics appear to be unstable and overlapping at least in some species.

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11

Beier, Cora L., Matthias Horn, Rolf Michel, Michael Schweikert, Hans-Dieter Görtz y Michael Wagner. "The Genus Caedibacter Comprises Endosymbionts of Paramecium spp. Related to the Rickettsiales (Alphaproteobacteria) and to Francisella tularensis (Gammaproteobacteria)". Applied and Environmental Microbiology 68, n.º 12 (diciembre de 2002): 6043–50. http://dx.doi.org/10.1128/aem.68.12.6043-6050.2002.

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ABSTRACT Obligate bacterial endosymbionts of paramecia able to form refractile inclusion bodies (R bodies), thereby conferring a killer trait upon their ciliate hosts, have traditionally been grouped into the genus Caedibacter. Of the six species described to date, only the Paramecium caudatum symbiont Caedibacter caryophilus has been phylogenetically characterized by its 16S rRNA gene sequence, and it was found to be a member of the Alphaproteobacteria related to the Rickettsiales. In this study, the Caedibacter taeniospiralis type strain, an R-body-producing cytoplasmatic symbiont of Paramecium tetraurelia strain 51k, was investigated by comparative 16S rRNA sequence analysis and fluorescence in situ hybridization with specific oligonucleotide probes. C. taeniospiralis is not closely related to C. caryophilus (80% 16S rRNA sequence similarity) but forms a novel evolutionary lineage within the Gammaproteobacteria with the family Francisellaceae as a sister group (87% 16S rRNA sequence similarity). These findings demonstrate that the genus Caedibacter is polyphyletic and comprises at least two phylogenetically different bacterial species belonging to two different classes of the Proteobacteria. Comparative phylogenetic analysis of C. caryophilus, five closely related Acanthamoeba endosymbionts (including one previously uncharacterized amoebal symbiont identified in this study), and their hosts suggests that the progenitor of the alphaproteobacterial C. caryophilus lived within acanthamoebae prior to the infection of paramecia.

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12

Budiardi, T., T. Nursyams y Agus Oman Sudrajat. "Survival Rate and Growth of Fighting Fish Larvae (Betta splendens Regan) Fed on Various Live Foods". Jurnal Akuakultur Indonesia 4, n.º 1 (1 de enero de 2007): 13. http://dx.doi.org/10.19027/jai.4.13-16.

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Larval of fighting fish (Betta splendens Regan) requires precise live foods for its growth and survival. In this experiment, fish larvae were fed on either Paramecium + Artemia, Paramecium + Artemia + Tubifex, Paramecium + Moina, or Paramecium + Moina + Tubifex. The fish were fed Paramecium from day-2 till day-7 after hatching. There after, the live food was changed according to the treatments till day-28. Results showed that fish fed on Paramecium + Artemia significantly had the highest total length (12.63 mm) than other treatments (11.86 mm). On the other hand, survival rate of fish had no significant affected by the treatments. Keywords: fighting fish, Betta splendens, Paramecium, Moina, Artemia, Tubifex, larvae ABSTRAK Larva ikan betta (Betta splendens Regan) membutuhkan jenis pakan alami yang tepat bagi kelangsungan hidup dan pertumbuhannya. Pada penelitian ini, larva ikan diberi pakan berupa Paramecium + Artemia, Paramecium + Artemia + Tubifex, Paramecium + Moina, atau Paramecium + Moina + Tubifex. Ikan diberi pakan pakan berupa Paramecium dari hari ke-2 hingga hari ke-7. Setelah itu, pemberian pakan alami diubah berdasarkan masing-masing perlakuan hingga hari ke-28. Hasil penelitian menunjukkan bahwa ikan yang diberi pakan Paramecium + Artemia memiliki tubuh secara signifikan lebih panjang (12,63 mm) dibandingkan perlakuan lainnya (11,86 mm). Sementara itu, kelangsungan hidup tidak dipengatuhi oleh perlakuan. Kata kunci: ikan betta, Betta splendens, Paramecium, Moina, Artemia, Tubifex, larva

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SCHMIDT, HELMUT J., FINN R. POND y HANS-DIETER GÖRTZ. "Refractile bodies (R bodies) from the macronuclear killer particle Caedibacter caryophila". Journal of Cell Science 88, n.º 2 (1 de septiembre de 1987): 177–84. http://dx.doi.org/10.1242/jcs.88.2.177.

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The macronuclei of certain isolates of Paramecium caudatum are inhabited by the bacterial endonucleobiont Caedibacter caryophila. These symbionts confer upon host paramecia a killer trait, which is clearly associated with the presence of R bodies in the endosymbionts. R bodies are unique inclusion bodies of caedibacteria (which are obligate endosymbionts of Paramecium) and of certain free-living bacteria of the genus Pseudomonas. They have been grouped into four classes on the basis of morphology and behaviour. A fifth R body type, introduced in this study, is named the Cc R body to indicate its presence in bright particles of Caedibacter caryophila. Type Cc R bodies are approximately 0.8 μm in width and diameter. They unroll in a telescopic fashion from the inside and are distinguished by a tapered inner and a blunt outer terminus. They are further associated with icosahedral bacteriophages, which stick to the inner terminus. Cc R body proteins show a ladder-like pattern of stained bands on polyacrylamide gels and exhibit a certain degree of antigenic cross-reactivity with type 51 R bodies.

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14

Przyboś, Ewa, Małgorzata Prajer, Magdalena Greczek-Stachura, Sergei I. Fokin, Maria Rautian y Alexey Potekhin. "New European Stands of Paramecium pentaurelia, Paramecium septaurelia, and Paramecium dodecaurelia, Genetic and Molecular Studies". Folia Biologica 53, n.º 3 (1 de octubre de 2005): 123–28. http://dx.doi.org/10.3409/173491605775142729.

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15

Tarcz, Sebastian, Marta Surmacz y Ewa Przyboś. "Sampling hidden microbial eukaryotic biodiversity in the tropics: new insights from the Paramecium aurelia complex (Ciliophora, Protozoa)". Folia Biologica 71, n.º 3 (29 de septiembre de 2023): 159–70. http://dx.doi.org/10.3409/fb_71-3.16.

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Ciliates, including the genus Paramecium, are among the most thoroughly researched groups of free-living microbial eukaryotes. However, our knowledge of their biodiversity appears to be restricted. Therefore, more data is required for tropical regions, to generate a more accurate picture of the distribution of the cryptic Paramecium species. In the current paper, recent data on the tropical biodiversity of the Paramecium aurelia species complex is presented. We believe that the COI mtDNA fragment allows for an evaluation of the geographic variation of particular cryptic species within the Paramecium aurelia complex, while also being sufficient for species identification. The obtained data indicates that the examined tropical populations may be very variable (with more than 50% previously unknown COI haplotypes discovered). Consequently, it is reasonable to assume that tropical environments reveal a high biodiversity of Paramecium ciliates.

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HIRANO, Akira, Toshio TSUJI, Noboru TAKIGUCHI y Hisao OHTAKE. "Simulation for Chemotactic Response of Paramecium Using Virtual Paramecium". Transactions of the Society of Instrument and Control Engineers 42, n.º 11 (2006): 1252–59. http://dx.doi.org/10.9746/sicetr1965.42.1252.

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17

Meyer, E., F. Caron y A. Baroin. "Macronuclear structure of the G surface antigen gene of Paramecium primaurelia and direct expression of its repeated epitopes in Escherichia coli". Molecular and Cellular Biology 5, n.º 9 (septiembre de 1985): 2414–22. http://dx.doi.org/10.1128/mcb.5.9.2414-2422.1985.

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The gene encoding the G surface antigen of Paramecium primaurelia was cloned from a macronuclear DNA library by a screening procedure involving differential hybridization with cDNA probes synthesized from polyadenylated RNAs of cells expressing one of two alternate antigens. S1 mapping experiments and sequencing of the cloned DNA and the mRNA showed that the cloned gene corresponded to the high-molecular-weight mRNA that had been indirectly identified as that of the G surface antigen. Because the genetic code of Paramecium spp. is different from the "universal" code, this mRNA cannot be correctly translated in vitro; direct proof that it encoded the antigenic determinants of this protein was therefore obtained through expression of fragments of the coding sequence in Escherichia coli by using the expression vector lambda gt11. Studies on the structure of this gene revealed that the central part of the coding sequence contained at least five tandem repeats of 222 base pairs, encoding immunogenic domains of the protein. We also showed that, like other surface antigen genes of trypanosomes and paramecia, this gene lay next to a chromosome end and that no rearrangement of its immediate genomic environment was associated with its expression.

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Meyer, E., F. Caron y A. Baroin. "Macronuclear structure of the G surface antigen gene of Paramecium primaurelia and direct expression of its repeated epitopes in Escherichia coli." Molecular and Cellular Biology 5, n.º 9 (septiembre de 1985): 2414–22. http://dx.doi.org/10.1128/mcb.5.9.2414.

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The gene encoding the G surface antigen of Paramecium primaurelia was cloned from a macronuclear DNA library by a screening procedure involving differential hybridization with cDNA probes synthesized from polyadenylated RNAs of cells expressing one of two alternate antigens. S1 mapping experiments and sequencing of the cloned DNA and the mRNA showed that the cloned gene corresponded to the high-molecular-weight mRNA that had been indirectly identified as that of the G surface antigen. Because the genetic code of Paramecium spp. is different from the "universal" code, this mRNA cannot be correctly translated in vitro; direct proof that it encoded the antigenic determinants of this protein was therefore obtained through expression of fragments of the coding sequence in Escherichia coli by using the expression vector lambda gt11. Studies on the structure of this gene revealed that the central part of the coding sequence contained at least five tandem repeats of 222 base pairs, encoding immunogenic domains of the protein. We also showed that, like other surface antigen genes of trypanosomes and paramecia, this gene lay next to a chromosome end and that no rearrangement of its immediate genomic environment was associated with its expression.

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19

Levilliers, N., A. Fleury y A. M. Hill. "Monoclonal and polyclonal antibodies detect a new type of post-translational modification of axonemal tubulin". Journal of Cell Science 108, n.º 9 (1 de septiembre de 1995): 3013–28. http://dx.doi.org/10.1242/jcs.108.9.3013.

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Polyclonal (PAT) and monoclonal (AXO 49) antibodies against Paramecium axonemal tubulin were used as probes to reveal tubulin heterogeneity. The location, the nature and the subcellular distribution of the epitopes recognized by these antibodies were, respectively, determined by means of: (i) immunoblotting on peptide maps of Paramecium, sea urchin and quail axonemal tubulins; (ii) immunoblotting on ciliate tubulin fusion peptides generated in E. coli to discriminate antibodies directed against sequential epitopes (reactive) from post-translational ones (non reactive); and (iii) immunofluorescence on Paramecium cells, using throughout an array of antibodies directed against tubulin sequences and post-translational modifications as references. AXO 49 monoclonal antibody and PAT serum were both shown to recognize epitopes located near the carboxyl-terminal end of both subunits of Paramecium axonemal tubulin, whereas the latter recognized additional epitopes in alpha-tubulin; AXO 49 and a fraction of the PAT serum proved to be unreactive over fusion proteins; both PAT and AXO 49 labelled a restricted population of very stable microtubules in Paramecium, consisting of axonemal and cortical ones, and their reactivity was sequentially detected following microtubule assembly; finally, both antibodies stained two upward spread bands in Paramecium axonemal tubulin separated by SDS-PAGE, indicating the recognition of various alpha- and beta-tubulin isoforms displaying different apparent molecular masses. These data, taken as a whole, definitely establish that PAT and AXO 49 recognize a post-translational modification occurring in axonemal microtubules of protozoa as of metazoa. This modification appears to be distinct from the previously known ones, and all the presently available evidence indicates that it corresponds to the very recently discovered polyglycylation of Paramecium axonemal alpha- and beta-tubulin.

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20

Murakami, Akira y Keiichi Takahashi. "Gravitaxis in Paramecium". Biological Sciences in Space 2, n.º 4 (1988): 228–37. http://dx.doi.org/10.2187/bss.2.228.

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COLEMAN, ANNETTE W. "Paramecium aurelia revisited". Journal of Eukaryotic Microbiology 52, n.º 2 (marzo de 2005): 7S—27S. http://dx.doi.org/10.1111/j.1550-7408.2005.05202003_1_17.x.

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Coleman, A. W. "Paramecium aurelia Revisited". Journal of Eukaryotic Microbiology 52, n.º 1 (febrero de 2005): 68–77. http://dx.doi.org/10.1111/j.1550-7408.2005.3327r.x.

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23

Fujishima, Masahiro y Yuuki Kodama. "Endosymbionts in Paramecium". European Journal of Protistology 48, n.º 2 (mayo de 2012): 124–37. http://dx.doi.org/10.1016/j.ejop.2011.10.002.

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24

Kaneshiro, E. S. "Lipids of Paramecium". Journal of Lipid Research 28, n.º 11 (noviembre de 1987): 1241–58. http://dx.doi.org/10.1016/s0022-2275(20)38590-4.

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25

Van Houten, Judith. "A Review for the Special Issue on Paramecium as a Modern Model Organism". Microorganisms 11, n.º 4 (3 de abril de 2023): 937. http://dx.doi.org/10.3390/microorganisms11040937.

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This review provides background and perspective for the articles contributing to the Special Issue of MDPI Micro-organisms on Paramecium as a Modern Model Organism. The six articles cover a variety of topics, each taking advantage of an important aspect of Paramecium biology: peripheral surface proteins that are developmentally regulated, endosymbiont algae and bacteria, ion channel regulation by calmodulin, regulation of cell mating reactivity and senescence, and the introns that dwell in the large genome. Each article highlights a significant aspect of Paramecium and its versatility.

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McCormick-Graham, M. y D. P. Romero. "A single telomerase RNA is sufficient for the synthesis of variable telomeric DNA repeats in ciliates of the genus Paramecium." Molecular and Cellular Biology 16, n.º 4 (abril de 1996): 1871–79. http://dx.doi.org/10.1128/mcb.16.4.1871.

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Paramecium telomeric DNA consists largely of a random distribution of TTGGGG and TTTGGG repeats. Given the precise nature of other ciliate telomerases, it has been postulated that there are two distinct types of the Paramecium enzyme, each synthesizing perfect telomeric repeats: one with a template RNA that specifies the addition of TTTGGG and the second dictating the synthesis of TTGGGG repeats. We have cloned and sequenced telomerase RNA genes from Paramecium tetraurelia, P. primaurelia, P. multimicronucleatum, and P. caudatum. Surprisingly, a single gene encodes telomerase RNA in all four species, although an apparently nontranscribed pseudogene is also present in the genome of P. primaurelia. The overall lengths of the telomerase RNAs range between 202 and 209 nucleotides, and they can be folded into a conserved secondary structure similar to that derived for other ciliate RNAs. All Paramecium telomerase RNAs examined include a template specific for the synthesis of TTGGGG telomeric repeats, which has not been posttranscriptionally edited to account for the conventional synthesis of TTTGGG repeats. On the basis of these results, possible mechanisms for the synthesis of variable telomeric repeats by Paramecium telomerase are discussed.

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Deregnaucourt, C., A. M. Keller y Y. Capdeville. "A new class of Paramecium surface proteins anchored in the plasma membrane by a glycosylinositol phospholipid. Membrane anchor of Paramecium cross-reacting glycoproteins". Biochemical Journal 253, n.º 2 (15 de julio de 1988): 395–400. http://dx.doi.org/10.1042/bj2530395.

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Treatment of paramecia with ethanol or Triton X-100 solubilizes a major membrane protein, namely the surface antigen (SAg), and a set of glycopeptides in the range 40-60 kDa, which cross-react with the SAg. We demonstrate that these glycopeptides, called ‘cross-reacting glycoproteins’ (CRGs), are distinct molecules from the SAg. First, after purification of CRGs from ethanolic extracts of Paramecium primaurelia expressing the 156G SAg, the amino acid composition of a given CRG was found to be different from, and incompatible with, that of the 156G SAg. Secondly, we showed that the CRGs, although not immunologically detectable, are present in fractions containing the myristoylated form of the 156G SAg. The treatment of these fractions by phosphatidylinositol-specific phospholipases C enables us to reveal the CRGs through the unmasking of two distinct epitopes. One is the ‘cross-reacting determinant’ (CRD), initially described for the variant surface glycoproteins (VSGs) of Trypanosoma; the other determinant, called ‘det-2355’, is specific to the SAg and to the CRGs. Our results suggest that (1) phosphatidylinositol is covalently linked to the CRGs and (2) the CRD and the det-2355 are localized in the same region of the CRGs. We propose that the CRGs are a new set of surface proteins anchored in the cell membrane of Paramecium via a glycosylinositol phospholipid, in the same way as the SAgs.

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Goto, Hiromasa y Kuniharu Nakajima. "Cultivation of Paramecium Caudatum in the Presence of Physiologically Active Substances, and a Redox Active Polymer". International Letters of Chemistry, Physics and Astronomy 46 (enero de 2015): 26–29. http://dx.doi.org/10.18052/www.scipress.com/ilcpa.46.26.

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Cultivation of paramecium in the presence of physiologically active substances was carried out. We have monitored paramecium for 23 days in the solutions in the presence of physiologically active substances, and polyaniline as a redox active polymer.

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29

Goto, Hiromasa y Kuniharu Nakajima. "Cultivation of Paramecium Caudatum in the Presence of Physiologically Active Substances, and a Redox Active Polymer". International Letters of Chemistry, Physics and Astronomy 46 (26 de enero de 2015): 26–29. http://dx.doi.org/10.56431/p-vqpffx.

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Cultivation of paramecium in the presence of physiologically active substances was carried out. We have monitored paramecium for 23 days in the solutions in the presence of physiologically active substances, and polyaniline as a redox active polymer.

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30

Furukawa, Shunsuke, Chiaki Karaki y Tomonori Kawano. "Micro-Particle Transporting System Using Galvanotactically Stimulated Apo-Symbiotic Cells of Paramecium bursaria". Zeitschrift für Naturforschung C 64, n.º 5-6 (1 de junio de 2009): 421–33. http://dx.doi.org/10.1515/znc-2009-5-621.

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It is well known that Paramecium species including green paramecia (Paramecium bursaria) migrate towards the anode when exposed to an electric field in a medium. This type of a cellular movement is known as galvanotaxis. Our previous study revealed that an electric stimulus given to P. bursaria is converted to a galvanotactic cellular movement by involvement of T-type calcium channel on the plasma membrane [Aonuma et al. (2007), Z. Naturforsch. 62 c, 93 - 102]. This phenomenon has attracted the attention of bioengineers in the fields of biorobotics or micro-robotics in order to develop electrically controllable micromachineries. Here, we demonstrate the galvanotactic controls of the cellular migration of P. bursaria in capillary tubes (diameter, 1 - 2 mm; length, 30 - 240 mm). Since the Paramecium cells take up particles of various sizes, we attempted to use the electrically stimulated cells of P. bursaria as the vehicle for transportation of micro-particles in the capillary system. By using apo-symbiotic cells of P. bursaria obtained after forced removal of symbiotic algae, the uptake of the particles could be maximized and visualized. Then, electrically controlled transportations of particle-filled apo-symbiotic P. bursaria cells were manifested. The particles transported by electrically controlled cells (varying in size from nm to μm levels) included re-introduced green algae, fluorescence-labeled polystyrene beads, magnetic microspheres, emerald green fluorescent protein (EmGFP)-labeled cells of E. coli, Indian ink, and crystals of zeolite (hydrated aluminosilicate minerals with a micro-porous structure) and some metal oxides. Since the above demonstrations were successful, we concluded that P. bursaria has a potential to be employed as one of the micro-biorobotic devices used in BioMEMS (biological micro-electro-mechanical systems).

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Груздев, Глеб Андреевич, Ольга Вячеславовна Карпухина, Анатолий Николаевич Иноземцев, Александр Васильевич Латанов y Андрей Александрович Каменский. "Анализ двигательной активности инфузорий Paramecium caudatum как тест-система оценки свойств адреналина". Экспериментальная и клиническая фармакология 85, n.º 10 (9 de noviembre de 2022): 41–45. http://dx.doi.org/10.30906/0869-2092-2022-85-10-41-45.

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Работа посвящена исследованию зависимости двигательной активности Paramecium caudatum от концентрации адреналина в среде, в которой находятся исследуемые простейшие. Показано, что адреналин в диапазоне концентраций 5,5 · 10–8 – 5,5 · 10–18 моль/мл снижает двигательную активность, изменяет стратегию движения инфузорий (p < 0,00005), причем зависимость силы воздействия на поведение от дозы адреналина носит куполообразный характер. У Paramecium caudatum выявлена повышенная чувствительность рецепторов к адреналину относительно чувствительности адренорецепторов у высших животных: клетки способны реагировать на адреналин в среде даже в сверхнизкой концентрации до 5,5 · 10–18 моль/мл. Полученные данные демонстрируют широкий спектр поведенческих реакций Paramecium caudatum, что подтверждает их ценность и удобство в качестве модельных объектов для фармакологических и токсикологических исследований. Анализ двигательной активности Paramecium caudatum позволяет определять диапазон предполагаемых физиологических или рабочих концентраций и степень чувствительности живых клеток к адреномиметикам и адреноблокаторам. Всё это даёт возможность рассматривать данный модельный объект, как новую тест-систему для доклинических исследований.

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32

Devi, Arti, Hirofumi Kadono y Uma Maheshwari Rajagopalan. "Fast Assessment of Quality of Water Containing Inorganic Pollutants Using Laser Biospeckles in Microbioassay". Applied Sciences 14, n.º 13 (26 de junio de 2024): 5558. http://dx.doi.org/10.3390/app14135558.

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Recently, bioassay techniques have been gaining prominence in assessing water toxicity, offering comprehensive evaluations without identifying the individual chemical component. However, microscopic observation is a crucial component in microbioassays to know the critical features of the targeted microorganisms. However, as the microorganism’s size becomes smaller, observation becomes more difficult due to the narrower focal depth of the imaging system. To address this challenge, we propose a novel laser biospeckle non-imaging technique utilizing biospeckle patterns generated by microorganisms, enabling non-imaging assessments of their swimming ability. Paramecium and Euglena were used as microorganisms. Paramecium and Euglena were subjected to varying concentrations of heavy metal pollutants (Zn(NO3)2·6H2O and FeSO4·7H2O), and their swimming activity was quantified using a dynamic biospeckle analysis. The results show a concentration-dependent effect of Zn on both species, leading to decreased swimming ability at increased concentration. Conversely, Fe exhibited varying effects on Paramecia and Euglena, with the latter displaying tolerance at lower concentrations but a notable response at higher concentrations. The advantage of the method is that owing to the non-imaging system, an enormous number of microorganisms can be processed. Moreover, the method allows for an immediate and statistically significant estimation of their swimming ability in response to environmental pollution.

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33

HAUSER, Karin, Roland KISSMEHL, Jürgen LINDER, Jochen E. SCHULTZ, Friedrich LOTTSPEICH y Helmut PLATTNER. "Identification of isoforms of the exocytosis-sensitive phosphoprotein PP63/parafusin in Paramecium tetraurelia and demonstration of phosphoglucomutase activity". Biochemical Journal 323, n.º 1 (1 de abril de 1997): 289–96. http://dx.doi.org/10.1042/bj3230289.

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PP63 (parafusin) is a 63 kDa phosphoprotein which is very rapidly (within 80 ms) dephosphorylated (to P63) during triggered trichocyst exocytosis; this occurs selectively in exocytosis-competent Paramecium tetraurelia strains. In the present work, two cDNAs coding for PP63/parafusin have been isolated, one of which is a new isoform. These isoforms are 99.6% identical and are derived from two different genes. Similarity searches revealed 43-51% identity of the deduced amino acid sequences with known phosphoglucomutases from yeast and mammals. The sequences of two proteolytic peptides obtained from PP63/parafusin isolated from Paramecium are identical to parts of the amino acid sequence deduced from the major cDNA. The major cDNA was mutated from the macronuclear ciliate genetic code into the universal genetic code and expressed in Escherichia coli. The recombinant protein shows the same biochemical and immunological characteristics as the (P)P63/parafusin originally isolated from Paramecium. It has the same specific phosphoglucomutase activity as phosphoglucomutase from chicken muscle. We also show that recombinant P63-1/parafusin 1 is a substrate of an endogenous casein kinase from Paramecium, as is the originally isolated P63/parafusin. Polyclonal antibodies against recombinant P63-1/parafusin 1 were raised which recognized phosphoglucomutases from different sources. Thus we show that PP63/parafusin and phosphoglucomutase in Paramecium are identical.

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34

Nugroho, Failasuf Aulia y Janusz Fyda. "Uptake of plastic microbeads by ciliate Paramecium aurelia". Science, Technology and Innovation 9, n.º 2 (26 de septiembre de 2020): 1–9. http://dx.doi.org/10.5604/01.3001.0014.4173.

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Microplastics (MPs) are small fraction of plastics that are less than 5 mm in length. They are bountiful and widespread pollutants in the aquatic environment. A wide range of organisms which play an important role in the food web, ingest microplastic particles and transfer them to the higher trophic levels. In this work, ingestion of fluorescent polystyrene beads 2 µm of diameter by ciliated protozoa Paramecium aurelia in different concentrations and times of exposure was studied. We studied also the ingestion and clearance rate as well as formation of food vacuoles. The highest uptake of beads by ciliates reached 1047.2 ± 414.46 particles after 10 min of incubation. Food vacuoles formation reflected the ingestion rate of P. aurelia, which increased at higher beads concentration up to the10th minute of incubation and decreased afterwards. On the contrary, the clearance rate persisted to be higher at low concentration. These findings showed that maximum capacity of microplastics ingestion by paramecia depended on beads concentration and on time of exposure.

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35

Mogami, Yoshihiro, Junko Ishii y Shoji A. Baba. "Does Paramecium sense gravity? Mechanisms of the gravitactic behaviour of Paramecium." Biological Sciences in Space 9, n.º 1 (1995): 17–35. http://dx.doi.org/10.2187/bss.9.17.

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36

Mortuza, M. Golam, Toshiyuki Takahashi, Tatsuya Ueki, Toshikazu Kosaka, Hitoshi Michibata y Hiroshi Hosoya. "Toxicity and Bioaccumulation of Hexavalent Chromium in Green Paramecium, Paramecium bursaria". JOURNAL OF HEALTH SCIENCE 51, n.º 6 (2005): 676–82. http://dx.doi.org/10.1248/jhs.51.676.

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37

OOYA, MAYUMI, YOSHIHIRO MOGAMI, AKEMI IZUMIKUROTANI y SHOJI A. BABA. "GRAVITY-INDUCED CHANGES IN PROPULSION OF PARAMECIUM CAUDATUM: A POSSIBLE ROLE OF GRAVIRECEPTION IN PROTOZOAN BEHAVIOUR". Journal of Experimental Biology 163, n.º 1 (1 de febrero de 1992): 153–67. http://dx.doi.org/10.1242/jeb.163.1.153.

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The swimming behaviour of Paramecium was analyzed under natural and experimental hypergravity conditions. Paramecium that swam upwards (in the opposite direction to the gravitational force) along a straight path (straight swimmers) swam more slowly than those swimming downwards. This dependence of the swimming velocity on its direction relative to gravity can be partly interpreted as the consequence of sinking due to gravity if the propulsive force does not vary. The effect was different for Paramecium swimming along a circular path (curved swimmers). The difference in velocity between those swimming upwards and those swimming downwards was substantially smaller than would have been expected from sinking effects with invariant propulsion even after correcting for maximal hydrodynamic wall effects, indicating that Paramecium compensate for sinking caused by gravity by controlling their propulsion. The propulsive velocity evaluated by vector calculus increased both as Paramecium swam more sharply upwards and as the experimental gravitational force was increased. The dependence of propulsion on the swimming direction and on gravity was reduced in a high-density medium of nearly neutral buoyancy, suggesting that the site of gravireception is unlikely to be in the interior of the cell. The differences between straight and curved swimmers are discussed in terms of rapid adaptation of gravireceptors in the cell membrane, desensitization of mechanosensory channels and hyperactivation of ciliary activity in straight swimmers.

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38

Sellis, Diamantis, Frédéric Guérin, Olivier Arnaiz, Walker Pett, Emmanuelle Lerat, Nicole Boggetto, Sascha Krenek et al. "Massive colonization of protein-coding exons by selfish genetic elements in Paramecium germline genomes". PLOS Biology 19, n.º 7 (29 de julio de 2021): e3001309. http://dx.doi.org/10.1371/journal.pbio.3001309.

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Ciliates are unicellular eukaryotes with both a germline genome and a somatic genome in the same cytoplasm. The somatic macronucleus (MAC), responsible for gene expression, is not sexually transmitted but develops from a copy of the germline micronucleus (MIC) at each sexual generation. In the MIC genome of Paramecium tetraurelia, genes are interrupted by tens of thousands of unique intervening sequences called internal eliminated sequences (IESs), which have to be precisely excised during the development of the new MAC to restore functional genes. To understand the evolutionary origin of this peculiar genomic architecture, we sequenced the MIC genomes of 9 Paramecium species (from approximately 100 Mb in Paramecium aurelia species to >1.5 Gb in Paramecium caudatum). We detected several waves of IES gains, both in ancestral and in more recent lineages. While the vast majority of IESs are single copy in present-day genomes, we identified several families of mobile IESs, including nonautonomous elements acquired via horizontal transfer, which generated tens to thousands of new copies. These observations provide the first direct evidence that transposable elements can account for the massive proliferation of IESs in Paramecium. The comparison of IESs of different evolutionary ages indicates that, over time, IESs shorten and diverge rapidly in sequence while they acquire features that allow them to be more efficiently excised. We nevertheless identified rare cases of IESs that are under strong purifying selection across the aurelia clade. The cases examined contain or overlap cellular genes that are inactivated by excision during development, suggesting conserved regulatory mechanisms. Similar to the evolution of introns in eukaryotes, the evolution of Paramecium IESs highlights the major role played by selfish genetic elements in shaping the complexity of genome architecture and gene expression.

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39

Beliavskaia, Alexandra Y., Alexander V. Predeus, Sofya K. Garushyants, Maria D. Logacheva, Jun Gong, Songbao Zou, Mikhail S. Gelfand y Maria S. Rautian. "New Intranuclear Symbiotic Bacteria from Macronucleus of Paramecium putrinum—“Candidatus Gortzia Yakutica”". Diversity 12, n.º 5 (15 de mayo de 2020): 198. http://dx.doi.org/10.3390/d12050198.

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Holospora-like bacteria (HLB) are obligate intracellular Alphaproteobacteria, inhabiting nuclei of Paramecium and other ciliates such as “Candidatus Hafkinia” is in Frontonia. The HLB clade is comprised of four genera, Holospora, Preeria, “Candidatus Gortzia”, and “Candidatus Hafkinia”. These bacteria have a peculiar life cycle with two morphological forms and some degree of specificity to the host species and the type of nucleus they inhabit. Here we describe a novel species of HLB—“Candidatus Gortzia yakutica” sp. nov.—a symbiont from the macronucleus of Paramecium putrinum, the first described HLB for this Paramecium species. The new endosymbiont shows morphological similarities with other HLB. The phylogenetic analysis of the SSU rRNA gene places it into the “Candidatus Gortzia” clade.

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40

Kim, Kwanghee, Min Son, Joan B. Peterson y David L. Nelson. "Ca2+-binding proteins of cilia and infraciliary lattice ofParamecium tetraurelia: their phosphorylation by purified endogenous Ca2+-dependent protein kinases". Journal of Cell Science 115, n.º 9 (1 de mayo de 2002): 1973–84. http://dx.doi.org/10.1242/jcs.115.9.1973.

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We purified two small, acidic calcium-binding proteins(ParameciumCa2+-binding proteins, PCBP-25α and PCBP-25β) from Paramecium tetraurelia by Ca2+-dependent chromatography on phenyl-Sepharose and by anion-exchange chromatography. The proteins were immunologically distinct. Monoclonal antibodies against PCBP-25β did not react with PCBP-25α, and antibodies against centrin from Chlamydomonas reacted with PCBP-25α but not with PCBP-25β. Like the centrins described previously, both PCBPs were associated with the infraciliary lattice (ICL), a fibrillar cytoskeletal element in Paramecium. Both were also present in isolated cilia, from which they could be released (with dynein) by a high-salt wash, and both PCBPs cosedimented with dynein in a sucrose gradient. PCBP-25β was especially prominent in cilia and in the deciliation supernatant, a soluble fraction released during the process of deciliation. The results of immunoreactivity and localization experiments suggest that PCBP-25α is a Paramecium centrin and that PCBP-25β is a distinct Ca2+-binding protein that confers Ca2+ sensitivity on some component of the cilium, ciliary basal body or ICL.We characterized these proteins and Paramecium calmodulin as substrates for two Ca2+-dependent protein kinases purified from Paramecium. PCBP-25α and calmodulin were in vitro substrates for one of the two Ca2+-dependent protein kinases (CaPK-2), but only PCBP-25α was phosphorylated by CaPK-1. These results raise the possibility that the biological activities of PCBP-25α and calmodulin are regulated by phosphorylation.

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41

Valentine, Megan y Judith Van Houten. "Using Paramecium as a Model for Ciliopathies". Genes 12, n.º 10 (24 de septiembre de 2021): 1493. http://dx.doi.org/10.3390/genes12101493.

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Paramecium has served as a model organism for the studies of many aspects of genetics and cell biology: non-Mendelian inheritance, genome duplication, genome rearrangements, and exocytosis, to name a few. However, the large number and patterning of cilia that cover its surface have inspired extraordinary ultrastructural work. Its swimming patterns inspired exquisite electrophysiological studies that led to a description of the bioelectric control of ciliary motion. A genetic dissection of swimming behavior moved the field toward the genes and gene products underlying ciliary function. With the advent of molecular technologies, it became clear that there was not only great conservation of ciliary structure but also of the genes coding for ciliary structure and function. It is this conservation and the legacy of past research that allow us to use Paramecium as a model for cilia and ciliary diseases called ciliopathies. However, there would be no compelling reason to study Paramecium as this model if there were no new insights into cilia and ciliopathies to be gained. In this review, we present studies that we believe will do this. For example, while the literature continues to state that immotile cilia are sensory and motile cilia are not, we will provide evidence that Paramecium cilia are clearly sensory. Other examples show that while a Paramecium protein is highly conserved it takes a different interacting partner or conducts a different ion than expected. Perhaps these exceptions will provoke new ideas about mammalian systems.

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42

Weitzman, Jonathan B. "Downsizing the Paramecium genome". Genome Biology 1 (2000): spotlight—20001109–02. http://dx.doi.org/10.1186/gb-spotlight-20001109-02.

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43

Ng, Stephen F. y Lai-Wa Tam. "Stomatogenesis in Paramecium tetraurelia". European Journal of Protistology 23, n.º 2 (marzo de 1988): 141–51. http://dx.doi.org/10.1016/s0932-4739(88)80057-9.

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44

Van Houten, Judith. "Chemosensory transduction in Paramecium". European Journal of Protistology 34, n.º 3 (octubre de 1998): 301–7. http://dx.doi.org/10.1016/s0932-4739(98)80057-6.

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45

Saimi, Y. y C. Kung. "Behavioral Genetics of Paramecium". Annual Review of Genetics 21, n.º 1 (diciembre de 1987): 47–65. http://dx.doi.org/10.1146/annurev.ge.21.120187.000403.

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46

Hasegawa, K. y A. Tanakadate. "The Paramecium circadian clock". Science of Nature 75, n.º 5 (mayo de 1988): 263–65. http://dx.doi.org/10.1007/bf00378022.

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47

Bell, W. E., W. Karstens, Y. Sun y J. L. Van Houten. "Biotin chemoresponse in Paramecium". Journal of Comparative Physiology A: Sensory, Neural, and Behavioral Physiology 183, n.º 3 (21 de septiembre de 1998): 361–66. http://dx.doi.org/10.1007/s003590050262.

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48

PLATTNER, H., C. LUMPERT, G. KNOLL, R. KISSMEHL, B. HOHNE y M. MOMAYEZI. "Exocytosis in paramecium cells". Cell Biology International Reports 14 (septiembre de 1990): 20. http://dx.doi.org/10.1016/0309-1651(90)90188-5.

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49

Plattner, Helmut. "My favorite cell?Paramecium". BioEssays 24, n.º 7 (21 de junio de 2002): 649–58. http://dx.doi.org/10.1002/bies.10112.

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50

Allen, Sally Lyman, Marsha I. Altschuler, Peter J. Bruns, Jean Cohen, F. Paul Doerder, Jacek Gaertig, Martin Gorovsky, Eduardo Orias y Aaron Turkewitz. "Proposed Genetic Nomenclature Rules for Tetrahymena thermophila, Paramecium primaurelia and Paramecium tetraurelia". Genetics 149, n.º 1 (1 de mayo de 1998): 459–62. http://dx.doi.org/10.1093/genetics/149.1.459.

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Abstract The genetics of the ciliated protozoa Tetrahymena thermophila and certain species of Paramecium (P. primaurelia and P. tetraurelia) have reached a level of maturity such that rules for genetic nomenclature for micronuclear and macronuclear genetics need to be clarified for workers in the field as well as for other geneticists. After a short introduction, the rules follow.

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