Abstract：
:Nuclear phenomena at conjugation of the multimicronucleate ciliate Blepharisma japonicum were investigated by using fluorescence microscopy. Several hours after cells united in pairs, micronuclei differentiated into meiotic micronuclei and "somatomicronuclei". Meiotic micro-nuclei participated in conventional sexual processes producing new micro- and macronuclei through meiosis, karyogamy and postkaryogamic mitoses. On the other hand, somatomicronuclei participated in characteristic asexual processes in which each micronucleus differentiated into a macronucleus without undergoing any nuclear division and karyogamy. These two paths of macronucleus differentiation, one sexual and the other asexual, proceeded side by side in each cell, but eventually one path dominated the other. The sexual path regularly dominated in crossing conjugation which was induced by mixing clones of complementary mating types I and II. However, if macronuclear anlagen in the sexual path were removed, the asexual path took over to form macronuclei, indicating that the asexual path serves as a reserve path of macronucleus formation. The asexual path regularly dominated in intraclonal conjugation of high-frequency selfers, suggesting that it functions in reducing the genetic effect of inbreeding. These findings not only clarify nuclear phenomena at conjugation in Blepharisma, but also provide a new opportunity for the study of macronucleus differentiation.
journal_name
Eur J Protistoljournal_title
European journal of protistologyauthors
Miyake A,Rivola V,Harumoto Tdoi
10.1016/S0932-4739(11)80340-8subject
Has Abstractpub_date
1991-06-21 00:00:00pages
178-200issue
2eissn
0932-4739issn
1618-0429pii
S0932-4739(11)80340-8journal_volume
27pub_type
杂志文章abstract：:Lake Tanganyika is world famous for a fauna that is rich in endemic species. On the other hand, it seems to be particularly poor in species of planktonic ciliates. Only the coastal infusorial fauna, for the most part mesopsammic, constitutes an extensive biomass with relatively few species. However, some are character...
journal_title：European journal of protistology
pub_type： 杂志文章
doi：10.1016/S0932-4739(11)80144-6
更新日期：1991-02-22 00:00:00
abstract：:The morphology and the infraciliature of Pseudokeronopsis rubra [7, 10, 11], P. carnea [8] nov. comb, and P. flava [8] nov. comb, are redescribed using protargol silver staining, biometry, and chromatography. These species differ in the colour and composition of the pigment granules, the length of the midventral rows,...
journal_title：European journal of protistology
pub_type： 杂志文章
doi：10.1016/S0932-4739(87)80010-X
更新日期：1987-11-01 00:00:00
abstract：:We have characterized the intracellular development and ultrastructure of a novel parasite that infected the marine benthic dinoflagellate Prorocentrum fukuyoi. The parasite possessed a combination of features described for perkinsids and syndineans, and also possessed novel characters associated with its parasitic li...
journal_title：European journal of protistology
pub_type： 杂志文章
doi：10.1016/j.ejop.2007.08.004
更新日期：2008-02-01 00:00:00
abstract：:More than 1000 secretory organelles (trichocysts) are docked at the plasma membrane of Paramecium cells. After stimulation, the trichocyst contents are expelled as needle-like structures in an exocytotic response. Neither the function nor the natural stimulus of trichocyst exocytosis are known in this well established...
journal_title：European journal of protistology
pub_type： 杂志文章
doi：10.1016/S0932-4739(11)80256-7
更新日期：1991-11-29 00:00:00
abstract：:A new Naegleria species, N. andersoni, is described that occurs world-wide. The new species consists of two subspecies and can be distinguished from previously described species on the basis of antigenic, isoenzyme and restriction enzyme DNA fragment differences and in maximum growth temperature tolerated. N. anderson...
journal_title：European journal of protistology
pub_type： 杂志文章
doi：10.1016/S0932-4739(88)80022-1
更新日期：1988-10-01 00:00:00
abstract：:Differences in gel electrophoretic mobility were used to compare tubulin subunits from a variety of distantly related ciliate species. The relative electrophoretic mobility of ciliate tubulins is shown to vary depending upon the electrophoretic conditions used to separate them. Tubulin migration is altered by changing...
journal_title：European journal of protistology
pub_type： 杂志文章
doi：10.1016/S0932-4739(11)80271-3
更新日期：1993-05-28 00:00:00
abstract：:Cotterillia bromelicola nov. gen., nov. spec. was discovered in the tanks of the Mexican bromeliad Tillandsia heterophylla. Its morphology, ontogenesis, and 18S rDNA were studied with standard methods. Cotterillia has many cirral rows on both sides of the body. Uniquely, and thus used to diagnose the new genus Cotteri...
journal_title：European journal of protistology
pub_type： 杂志文章
doi：10.1016/j.ejop.2010.08.003
更新日期：2011-01-01 00:00:00
abstract：:The living morphology, infraciliature and morphogenesis of a new ciliate, Urosomoida paragiliformis n. sp., collected from saline soil in Weinan, China, were studied in vivo and after protargol staining. Urosomoida paragiliformis n. sp. is characterized as follows: body elongate-elliptical with no tail, flexible and s...
journal_title：European journal of protistology
pub_type： 杂志文章,评审
doi：10.1016/j.ejop.2016.07.005
更新日期：2016-10-01 00:00:00
abstract：:Resting cysts of Parentocirrus hortualis were investigated, using live observation, SEM and TEM. Processes during encystation and excystation were observed in vivo under the light microscope. During encystation, the trophic body becomes globular, the ciliature is resorbed in an anterior direction, the macronuclear nod...
journal_title：European journal of protistology
pub_type： 杂志文章
doi：10.1016/j.ejop.2015.12.003
更新日期：2016-04-01 00:00:00
abstract：:The morphology, infraciliature and silverline system of Trachelocerca trepida Kahl, 1928 has been reinvestigated. The species was found in marine water (Yellow Sea) near Shanghai, Eastchina. Stained specimens (protargol) are characterized morphometrically. The shape of the extrusomes (toxicysts) and the structure of o...
journal_title：European journal of protistology
pub_type： 杂志文章
doi：10.1016/S0932-4739(11)80110-0
更新日期：1990-10-19 00:00:00
abstract：:The morphology of four cyrtophorian ciliates, Dysteria ovalis, D. semilunaris, Phascolodon vorticella, and Chlamydonellopsis calkinsi, were investigated using living observation and protargol-staining. The morphology of D. ovalis is revealed in detail for the first time, and it is characterized by the following combin...
journal_title：European journal of protistology
pub_type： 杂志文章
doi：10.1016/j.ejop.2016.08.005
更新日期：2016-10-01 00:00:00
abstract：:The effects of 0.2-2.0 mM PtCl(4) have been investigated, the purpose was to test whether the compound would affect Tetrahymena in a manner similar to that of cis-dichlorodiammine-platinum(II), or cisplatin, which in 0.83 mM inhibits cell proliferation for 24 h and induces diminution of the inner mitochondrial membran...
journal_title：European journal of protistology
pub_type： 杂志文章
doi：10.1016/S0932-4739(11)80044-1
更新日期：1992-05-22 00:00:00
abstract：:The morphology and infraciliature of two Frontonia species, F. shii spec. nov. and F. paramagna Chen et al., 2014, isolated from a freshwater pond in northeastern China, were investigated using living observation and silver staining methods Frontonia shii spec. nov. is recognized by the combination of the following ch...
journal_title：European journal of protistology
pub_type： 杂志文章
doi：10.1016/j.ejop.2018.01.002
更新日期：2018-04-01 00:00:00
abstract：:In a study on ciliate diversity, we discovered the new hypotrich species, Gonostomum jangbogoensis n. sp., in freshwater from Terra Nova Bay, Victoria Land, southeast Antarctica. We describe its morphology and morphogenesis using standard methods, and the SSU rRNA gene phylogeny is provided as well. Morphology of Gono...
journal_title：European journal of protistology
pub_type： 杂志文章
doi：10.1016/j.ejop.2019.125669
更新日期：2020-04-01 00:00:00
abstract：:Mitotis in the choanoflagellate Monosiga sp. has been studied by electron microscopy for the first time based on serial sections of metaphase and anaphase. The dense metaphase plate is formed by chromosomes at the centre of the nucleus. Spindle poles are located at the opposite sides of this plate. The nuclear envelop...
journal_title：European journal of protistology
pub_type： 杂志文章
doi：10.1016/S0932-4739(11)80292-0
更新日期：1993-02-19 00:00:00
abstract：:The authors present light and electron microscopical data on a myxosporidian found in the gills of Crenicichla lepidota Heckel, 1840 (Teleostei, Cichlidae) from the Amazon river. Based on the spore morphology, it is concluded that this species belongs to the family Myxobolidae, genus Henneguya, and that it constitutes...
journal_title：European journal of protistology
pub_type： 杂志文章
doi：10.1016/S0932-4739(11)80233-6
更新日期：1992-08-21 00:00:00
abstract：:Shifts in community composition of soil protozoa in response to climate change may substantially influence microbial activity and thereby decomposition processes. However, effects of climate and vegetation on soil protozoa remain poorly understood. We studied the distribution of soil testate amoebae in herbaceous and ...
journal_title：European journal of protistology
pub_type： 杂志文章
doi：10.1016/j.ejop.2012.08.004
更新日期：2013-05-01 00:00:00
abstract：:We observed reproductive swarmer cells of the nassellarian and spumellarian polycystine radiolarians Didymocyrtis ceratospyris, Pterocanium praetextum, Tetrapyle sp., and Triastrum aurivillii using light, scanning and transmission electron microscopy. The swarmer cells had subspherical to ovoid or spindle shapes with ...
journal_title：European journal of protistology
pub_type： 杂志文章
doi：10.1016/j.ejop.2016.02.007
更新日期：2016-06-01 00:00:00
abstract：:Copidognathus nautilei Bartsch, 1997, from a hydrothermal vent field of the Mid-Atlantic Ridge at about 13 degrees N, 45 degrees W and 4090 m depth, was infested with the suctorian Corynophrya abyssalis n. sp., with up to 58 epizoans per mite. The new suctorian has a sacciform body with seven longitudinal ribs, a comp...
journal_title：European journal of protistology
pub_type： 杂志文章
doi：10.1016/j.ejop.2010.02.001
更新日期：2010-08-01 00:00:00
abstract：:The infraciliature and morphogenesis of Paraholosticha sterkii (Garnjobst, 1934) n. comb. (Basionym: Stylonethes sterkii) are described. Before division a cell encysts and after division each tomite forms an individual cyst within the common one. The ciliates cease to move and the kinetome is resorbed. With the beginn...
journal_title：European journal of protistology
pub_type： 杂志文章
doi：10.1016/S0932-4739(88)80038-5
更新日期：1988-07-01 00:00:00
abstract：:Dileptid and tracheliid ciliates have been traditionally classified within the subclass Haptoria of the class Litostomatea. However, their phylogenetic position among haptorians has been controversial and indicated that they may play a key role in understanding litostomatean evolution. In order to reconstruct the evol...
journal_title：European journal of protistology
pub_type： 杂志文章
doi：10.1016/j.ejop.2011.04.006
更新日期：2011-11-01 00:00:00
abstract：:The present study was undertaken to describe Cryptosporidium spp. infection in tree squirrels from 17 locations in Northern Italy. A total of 357 squirrels were examined, including species native to Europe (Sciurus vulgaris; n=123), and species introduced from North America (Sciurus carolinensis; n=162) and Southeast ...
journal_title：European journal of protistology
pub_type： 杂志文章
doi：10.1016/j.ejop.2017.09.007
更新日期：2017-10-01 00:00:00
abstract：:Licnophora chattoni, found in association with Zyzzyzus warreni, a tubulariid hydroid epizoic in sponges from São Sebastião (SP, Brazil), is redescribed and illustrated using light and electron microscopy. The ciliate has a flexible, transparent body formed by an oval anterior region linked to the posterior basal disc...
journal_title：European journal of protistology
pub_type： 杂志文章
doi：10.1016/j.ejop.2011.07.004
更新日期：2012-01-01 00:00:00
abstract：:Ookinetes of Leucocytozoon simondi have a Polar Ring Complex (PRC) which is composed of a stout electron-lucent polar ring with about 34 posteriorly extending tines. The latter are subtended by about 76 subpellicular microtubules. A broad collar of electron-dense material is associated with the cytoplasmic surface of ...
journal_title：European journal of protistology
pub_type： 杂志文章
doi：10.1016/S0932-4739(89)80061-6
更新日期：1989-04-14 00:00:00
abstract：:A new species of unicellular opisthokont protist, Nuclearia thermophila sp. nov., was isolated from the warm spring water of Yunoko Lake, Japan, and has been described using light and electron microscopy. It exists as a spherical floating form and a flattened amoeboid form showing various shapes. The cells occasionall...
journal_title：European journal of protistology
pub_type： 杂志文章
doi：10.1016/j.ejop.2008.09.004
更新日期：2009-05-01 00:00:00
abstract：:Pterospora demodendrion sp.nov., an acephaline eugregarine (Eugregarinorida, Urosporidae) from the coelom of Axiothella mucosa (Polychaeta, Maldanidae) is described. The gamont averages 277 × 139 μm and possesses 20-36 posterior prolongations. Gametocysts average 412 × 287 μm; without polar funneled openings. Oocysts ...
journal_title：European journal of protistology
pub_type： 杂志文章
doi：10.1016/S0932-4739(11)80427-X
更新日期：1991-03-28 00:00:00
abstract：:Microbial eukaryotes living in low oxygen environments often have novel physiological and morphological features that facilitate symbiotic relationships with bacteria and other means for acquiring nutrients. Comparative studies of these features provide evidence for phylogenetic relationships and evolutionary history....
journal_title：European journal of protistology
pub_type： 杂志文章
doi：10.1016/j.ejop.2012.07.001
更新日期：2013-01-01 00:00:00
abstract：:The living morphology, infraciliature and silverline system of two small marine Euplotes species, E. orientalis spec. nov. and E. raikoviAgamaliev, 1966, isolated from a sandy beach near Qingdao, China, were investigated. Euplotes orientalis is characterized by a combination of features including their small size (35-...
journal_title：European journal of protistology
pub_type： 杂志文章
doi：10.1016/j.ejop.2009.11.003
更新日期：2010-05-01 00:00:00
abstract：:The apostome ciliate Hyalophysa chattoni, a symbiont of the estuarine grass shrimp Palaemonetes pugio, was tested for its growth and reproductive ability in a wide range of salinities from 0.1 to 55 ppt. Shrimp, with their attached ciliates, were slowly acclimated to different salinities in order to assess protozoan c...
journal_title：European journal of protistology
pub_type： 杂志文章
doi：10.1016/j.ejop.2007.11.002
更新日期：2008-05-01 00:00:00
abstract：:Planktonic testate amoebae in floodplains exhibit a broad-range of morphological variability. The variation size is already known, but it is necessary to know how this is for morphological variables. This study aimed to identify the relationships between testate amoebae morphology and environmental factors in four neo...
journal_title：European journal of protistology
pub_type： 杂志文章
doi：10.1016/j.ejop.2016.08.006
更新日期：2016-10-01 00:00:00
