Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Ciliophora”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 19 recordsLinked to original sources
PubMed1986

Primary structure of the Paramecium tetraurelia small-subunit rRNA coding region: phylogenetic relationships within the Ciliophora.

We have sequenced the coding region for the small-subunit rRNA gene from Paramecium tetraurelia. Similarity comparisons between small-subunit rRNAs from representatives of the Metazoa, the Plantae, the Fungi and four other members of the Ciliophora were used to construct phylogenetic trees. In these phylogenies the Ciliophora diverged from the eukaryotic line of descent as a loose phylogenetic grouping during a radiative period that gave rise to the Fungi, the Plantae and the Metazoa.

Animals↗
PubMed2006

Morphology and cell division of the oxytrichids Architricha indica nov. gen., nov. sp., and Histriculus histrio (Müller, 1773), Corliss, 1960 (Ciliophora, Hypotrichida).

The oxytrichid ciliate Architricha indica nov. gen., nov. sp., isolated from the river Yamuna, Delhi, shows a new combination of characters. It possesses a flexible body, 18 frontal-ventral-transverse (FVT) cirri, 3 right and 2 left marginal cirral rows, 6 dorsal bristle rows and 3 caudal cirri (CC). The FVT cirri arise from 6 primordia, which utilize 6 parental cirri in their origin as is typical of Oxytricha species. Multiple marginal rows (MMR) develop through 5 independent marginal primordia arising "within-row", 1 in each parental marginal row. All the 5 marginal rows are thus morphogenetically active. Such a mode of formation of MMR has not been recorded among oxytrichids and has necessitated separation of A. indica at the generic level. Histriculus, on the other hand, has well-known characteristics, viz. rigid body, confluent marginal rows and absence of CC. The morphogenesis of Histriculus histrio has been described by Berger and Foissner [1997. Cladistic relationships and generic characterization of oxytrichid hypotrichs (Protozoa, Ciliophora). Arch. Protistenkd. 148, 125-155]. Reinvestigation of very early stages of development revealed that (i) the FVT cirral primordia utilize kinetosomes from 5 parental FVT cirri, (ii) the primordium II of the proter is of a composite origin: kinetosomes from the oral primordium merge with the primordium II that originates from the buccal cirrus II/2 and (iii) the FVT primordia V and VI for the 2 daughter cells arise sequentially from the parental cirrus V/4. Thus, the genus Histriculus exhibits a new combination of characters with respect to the origin of FVT cirri, an additional pattern to be added to the known 6 patterns of FVT development in oxytrichids [Berger and Foissner, 1997; Berger, H., 1999. Monograph of the Oxytrichidae (Ciliophora, Hypotrichida), Kluwer Academic Publishers, Dordrecht/Boston/London].

Animals↗
PubMed1999

Unusually high evolutionary rate of the elongation factor 1 alpha genes from the Ciliophora and its impact on the phylogeny of eukaryotes.

The elongation factor 1 alpha (EF-1 alpha) has become widely employed as a phylogenetic marker for studying eukaryotic evolution. However, a disturbing problem, the artifactual polyphyly of ciliates, is always observed. It has been suggested that the addition of new sequences will help to circumvent this problem. Thus, we have determined 15 new ciliate EF-1 alpha sequences, providing for a more comprehensive taxonomic sampling of this phylum. These sequences have been analyzed together with a representation of eukaryotic sequences using distance-, parsimony-, and likelihood-based phylogenetic methods. Such analyses again failed to recover the monophyly of Ciliophora. A study of the substitution rate showed that ciliate EF-1 alpha genes exhibit a high evolutionary rate, produced in part by an increased number of variable positions. This acceleration could be related to alterations of the accessory functions acquired by this protein, likely to those involving interactions with the cytoskeleton, which is very modified in the Ciliophora. The high evolutionary rate of these sequences leads to an artificial basal emergence of some ciliates in the eukaryotic tree by effecting a long-branch attraction artifact that produces an asymmetric topology for the basal region of the tree. The use of a maximum-likelihood phylogenetic method (which is less sensitive to long-branch attraction) and the addition of sequences to break long branches allow retrieval of more symmetric topologies, which suggests that the asymmetric part of the tree is most likely artifactual. Therefore, the sole reliable part of the tree appears to correspond to the apical symmetric region. These kinds of observations suggest that the general eukaryotic evolution might have consisted of a massive radiation followed by an increase in the evolutionary rates of certain groups that emerge artificially as early branches in the asymmetric base of the tree. Ciliates in the case of the EF-1 alpha genes would offer clear evidence for this hypothesis.

Amino Acid Sequence↗
PubMed2000

Trichodinid ectoparasites (Ciliophora: Peritrichida) of some River Nile fish, Egypt.

Four species of trichodinid ectoparasites (Ciliophora: Peritrichida) were collected from the gills of the following River Nile fish in Egypt: Hydrocynus forskalii, Mormyrus kannume, Schilbe mystus. These species are: Trichodina heterodentata Duncan, 1977, Trichodina fahaka sp. n., Trichodinella epizootica Raabe, 1950, Tripartiella dactylodentata sp. n. Photomicrographs and morphometric data are presented for each species.

Animals↗
PubMed2001

Phylogenetic relationships within the class Spirotrichea (Ciliophora) inferred from small subunit rRNA gene sequences.

The small subunit rDNAs of five species belonging to the Euplotidae and eight species of the Oxytrichidae were sequenced to obtain a more detailed picture of the phylogenetic relationships within the Spirotrichea (Ciliophora). Various tree reconstruction algorhythms yielded nearly identical topologies. All Euplotidae were separated from the other Spirotrichea by a deep split. Further, a large genetic distance between the marine genus Moneuplotes and the freshwater species of Euplotoides was found. Differences between the methods used occurred only within the Oxytrichidae. Whereas the monophyly of the Stylonychinae was supported in all trees, the monophyly of the Oxytrichinae was not. However, the molecular data support the morphological and ontogenetic evidence that the pattern of 18 frontal-ventral-transversal cirri evolved in the stemline of the Oxytrichidae and was modified several times independently. Our results are also in agreement with taxonomic revisions: the separation of both Sterkiella nova from Oxytricha and Tetmemena pustulata from Stylonychia.

Animals↗
PubMed2005

Spirostomum spp. (Ciliophora, Protista), a suitable system for endocytobiosis research.

Among ciliate genera, only Paramecium and Euplotes species have been studied extensively as host organisms of bacterial endocytobionts. In this article, we show that members of the genus Spirostomum may also serve as a suitable system for endocytobiosis research. Two strains of Spirostomum minus (Heterotrichea, Ciliophora) collected in Germany and Italy, respectively, were found to harbor different types of bacterial infections. Bacteria of various sizes and shapes were observed in the cytoplasm or in the nuclei of the ciliates. The bacteria in the cytoplasm were either surrounded by a peribacterial membrane or lay naked. One of the bacterial species was found in the vicinity of the contractile fibrillar system (myonemes) of the ciliates. In rare cases, another type of bacteria was observed associated with mitochondria. The macronuclei of both the Italian and the German strains were crowded with endocytobionts. The endonuclear bacteria in the two S. minus strains differed with respect to their cytoplasmic structures but they were of similar size and both were rod shaped. According to the results of in situ hybridization, the endonuclear bacteria of the Italian strain belong to the subgroup of alphaproteobacteria, whereas the bacteria associated with the fibrillar system appeared to be gram-positive bacteria with high G+C content. While both the German and the Italian strains were found to permanently maintain their endocytobionts, they were at least partly colonized by different bacteria. This is taken as an indication that geographically separated populations of ciliates may be stably infected by different endocytobionts, possibly due to different ecological conditions. For S. minus and S. ambiguum a total of 7 different bacterial endocytobionts have now been recorded. We recommend the members of the genus Spirostomum as a suitable system for endocytobiosis research.

Animals↗
PubMed1990

A new species of Trichodina (Ciliophora: Peritrichia) from the intestine of the surgeonfish Acanthurus xanthopterus.

A population of a trichodinid (Ciliophora: Peritrichia) was found in the gut of the surgeonfish Acanthurus xanthopterus collected from Hawaii, South Africa and New Guinea and described as a new species. This is only the second record of a trichodinid from the intestine of a marine fish. In all the fish specimens examined, the micro-fauna normally found in other species of the fish family. Acanthuridae was absent and replaced entirely by the trichodinid population.

Animals↗
PubMed1991

Parasitism of newly-hatched Aedes sierrensis (Diptera: Culicidae) larvae by Lambornella clarki (Ciliophora: Tetrahymenidae) following habitat flooding.

Host-parasite interactions between Lambornella clarki (Ciliophora: Tetrahymenidae) and its natural host, Aedes sierrensis (Diptera: Culicidae), were studied in newly flooded treeholes in northern California between 1986 and 1989. First instar host larvae hatched within 1 to 4 hr of flooding, while free-living trophonts of L. clarki appeared between 7 and 24 hr. As early as 24 hr after flooding, ciliates initiated the first parasite cycle by forming cuticular cysts on first instar larvae; by 64 hr, cysts were observed on larvae collected from all positive holes during all years. While larvae with as many as 12 cysts were observed, most supported only 1 cyst, and successful infections were established by the entry of a single ciliate into the host's hemocoel. Among treehole populations, the proportion of larvae with L. clarki cysts ranged from 2 to 100% at 48 hr indicating that enzootics and epizootics develop rapidly in newly flooded treeholes. Average attack rates from all holes by year ranged between 17.0 and 44.4%. Ciliates began entering hosts 48 to 72 hr after flooding, but some larvae escaped parasitization by molting to the second instar before ciliates penetrated the cuticle. In some treeholes, opportunistic microorganisms entered larvae with the invading ciliates and killed both the host and parasite.

Aedes↗
PubMed1975

Nuclear characteristics and phylogeny in the protistan phylum Ciliophora.

Ciliates possess a number of nuclear characteristics which, in combination, are unique among the Protista. Nevertheless, attempts to understand the origin - presumably from a flagellate ancestry - of the Ciliophora as a phylum must be made, as well as efforts to elucidate phylogenetic pathways within the large and diverse assemblage represented by its present-day forms. The macronucleus may provide an important clue to early ciliate phylogeny, since we still have, among extant species, groups of distinct "karyological relicts" exhibiting the very features expected in hypothetical forms corresponding to postulated stages in macronuclear origin and evolution. The relationship of the groups of "relict" species to the predominant polyploid-macronucleate forms, with a direct impact on the classification system as well as ciliate evolution and phylogeny in general, is discussed in some detail. Arguments are presented for taxonomic separation of the relatively primitive homokaryotic and diploid-macronucleate forms, which also share other features in common related to their being members of the interstitial fauna, from the more advanced ciliates. The problem is complicated by the non-nuclear structural complexities of these sand-dwelling forms, apparently secondarily-derived specializations which, by convergence, have come to resemble certain non-homologous features of the allegedly more highly evolved groups.

Biological Evolution↗
PubMed1985

Cortical ultrastructure of Coleps bicuspis Noland, 1925 and the phylogeny of the class Prostomatea (Ciliophora).

The ultrastructure of Coleps bicuspis Noland, 1925 is described. The ciliate is a typical prostomate: the somatic kinetid is a monokinetid with a postciliary ribbon at triple 9, a kinetodesmal fibril originating near triplets 5, 6, 7 and an apparently radial transverse ribbon at triplet 4. The oral area is circular and has three brosse kineties associated with it. The brosse kineties are composed of dikinetids whose anterior kinetosome bears a tangential transverse ribbon and whose posterior kinetosome bears the fibrillar associates typical of a somatic monokinetid. The oral dikinetids are oriented parallel to the circumference of the oral cavity, which is surrounded by oral papillae and oral ridges. Pairs of nematodesmata, originating from oral dikinetid kinetosomes, are typically triangular in transection. A phylogeny of rhabdophoran ciliates is presented using the mixed parsimony algorithm and is discussed with reference to the systematic revisions of the phylum Ciliophora.

Animals↗
PubMed1988

An update on the systematics of the phylum Ciliophora doflein, 1901: the implications of kinetid diversity.

Recent classifications of the phylum Ciliophora are compared with the system proposed by Small and Lynn in 1981 and revised in 1985. The classes COLPODEA, PHYLLOPHARYNGEA, OLIGOHYMENOPHOREA and NASSOPHOREA sensu Small & Lynn are considered monophyletic by a number of researchers. The classes LITOSTOMATEA and PROSTOMATEA sensu Small & Lynn are not as well accepted. Some divergence of opinion arises in recognition of the categories included in the classes KARYORELICTEA and SPIROTRICHEA sensu Small & Lynn, in which the great diversity of cortical ultrastructure is still not recognized in the taxonomy. Numerous minor groups, for example the phacodiniids, plagiopylids and schizocaryids, present taxonomic problems that may not be solved by ultrastructural examination. This is also true of the subphyletic divisions where there are substantial differences of opinion about relationships among the classes.

Animals↗
PubMed1988

The quest for the ancestor of the Ciliophora: a brief review of the continuing problem.

Although the assumption has long been made that the Ciliophora arose from flagellates, limited progress has been made in determining exactly what extant group - flagellate or other - may best resemble the ancestral "preciliate" assemblage. The distinctiveness of the ciliates and of the many protist phyla containing flagellated stages in their life cycles makes the recognition of potentially homologous features difficult. The suggestion that there may be a phylogenetic relationship between dinoflagellates and ciliates, while seeming unlikely from consideration of a number of specialized characters, is attracting increased attention. This is because some basic similarities (possibly shared derived characters) are characteristic of many species from both groups: cortical alveoli, tubular mitochondrial cristae, kinetidal systems, acentric mitoses with persisting nuclear envelope, functional cytostome, extrusomes (mucocytsts and explosive trichocysts), locomotory organelles, and small subunit rRNAs (close structural similarity values). But many questions remain unanalyzed or unanswered, and caution is still advisable in drawing any firm conclusions about the evolutionary closeness of ciliates and dinoflagellates.

Animals↗
PubMed2002

Taxonomy of trichodinids from the gills of marine fishes in coastal regions of the Yellow Sea, with descriptions of two new species of Trichodina Ehrenberg, 1830 (Protozoa: Ciliophora: Peritrichia).

Seven species of marine fishes from coastal regions of the Yellow Sea were examined for ectoparasitic trichodinids (Protozoa, Ciliophora). A total of seven species belonging to the genus Trichodina Ehrenberg, 1830, including two new species, occurred as gill parasites. These were T. rectispina n. sp., T. circinantis n. sp., T. frequentis Shtein, 1979, T. jarmilae Lom & Laird, 1969, T. hexagrammi Zhukov, 1964, T. minima Shtein, 1979 and T. ovonucleata Raabe, 1958. Each was investigated following silver nitrate and protargol impregnation. Morphometric data and comparative descriptions of these trichodinids are provided along with details of their prevalence and intensity of infestation.

Animals↗
PubMedDate not supplied

Phylogenetic relationships of the Nassulida within the phylum Ciliophora inferred from the complete small subunit rRNA gene sequences of Furgasonia blochmanni, Obertrumia georgiana, and Pseudomicrothorax dubius.

Using comparisons of complete small subunit rRNA sequences from the ciliated protozoans Furgasonia blochmanni, Obertrumia georgiana, and Pseudomicrothorax dubius we inferred the phylogenetic position of the Nassulida (Class Nassophorea) within the Ciliophora. In distance matrix analyses the Nassulida share a common ancestry with the colpodean ciliate Colpoda inflata. Distance matrix and parsimony methods convincingly demonstrate that the Nassulida plus Colpodida are members of a complex ciliate assemblage that also includes the oligohymenophorans and phyllopharyngeans. These phylogenetic inferences are largely congruent with recent analyses of 23S-like rRNA gene sequences and morphogenetic features. Groups traditionally thought to represent ancestral lineages now appear as highly derived ciliates. In contrast, heterotrichs which were considered to represent a highly evolved group, diverge at the base of the ciliates.

Animals↗
PubMedDate not supplied

Phylogenetic position of Licnophora, Lechriopyla, and Schizocaryum, three unusual ciliates (phylum Ciliophora) endosymbiotic in echinoderms (phylum Echinodermata).

Various echinoderms are colonized by species from several classes of the Phylum Ciliophora, indicating that the echinoderm "habitat" has been invaded independently on numerous occasions throughout evolutionary history. Two "echinoderm" ciliates whose phylogenetic positions have been problematic are Licnophora macfarlandi Stevens, 1901 and Schizocaryum dogieli Poljansky and Golikova, 1957. Licnophora macfarlandi is an endosymbiont of the respiratory trees of holothuroids, and S. dogieli is found in the esophagus of echinoids. A third species, Lechriopyla mystax Lynch, 1930, is a plagiopylid ciliate found in the intestine of echinoids. Host echinoderms were collected near the Friday Harbor Laboratories, San Juan Island, WA. Specimens of S. dogieli and L. mystax were obtained from the esophagus and intestine, respectively, of the sea urchin Strongylocentrotus pallidus. Specimens of L. macfarlandi were collected from the fluid obtained from the respiratory trees of Parastichopus californicus. Using small subunit ribosomal RNA (SSrRNA) sequences of these three ciliates and a global alignment of SSrRNA sequences of other ciliates, we established the following. 1) Licnophora is a spirotrich ciliate, clearly related to the hypotrichs and stichotrichs; this is corroborated by its possession of macronuclear replication bands. 2) Lechriopyla is the sister genus to Plagiopyla and is a member of the Class Plagiopylea, which was predicted based on its cytology. 3) Schizocaryum clusters in the Class Oligohymenophorea and is most closely related to the scuticociliates; there are currently no morphological features known to relate Schizocaryum to the scuticociliates.

Animals↗
PubMed1991

Phylogenetic relationships within the class Oligohymenophorea, phylum Ciliophora, inferred from the complete small subunit rRNA gene sequences of Colpidium campylum, Glaucoma chattoni, and Opisthonecta henneguyi.

Phylogenetic relationships within the class Oligohymenophorea, phylum Ciliophora, were investigated by determining the complete small subunit rRNA (SSrRNA) gene sequences for the hymenostomes Colpidium campylum, Glaucoma chattoni, and the peritrich Opisthonecta henneguyi. The affiliations of the oligohymenophoreans were assessed using both distance matrix (DM) and maximum parsimony (MP) analyses. Variations do exist in the phylogenies created by the two methods. However, the basic tree topologies are consistent. In both the DM and MP analyses the hymenostomes (C. campylum, G. chattoni, and the tetrahymenas) all form a very tight group associated with the peritrich O. henneguyi. The Tetrahymena lineage was monophyletic whereas Colpidium and Glaucoma were more closely related to each other than either was to the tetrahymenas. The monophyly of the genus Tetrahymena in the present analysis supports the phylogenies determined from morphological data and molecular sequence data from the histone H3II/H4II region of the genome. The perplexing and controversial phylogenetic position of the peritrichs is once again depicted in the present analysis. The distinctiveness of the peritrich Opisthonecta from both hymenostome and nassophorean ciliates based on evolutionary distances suggests that the elevation of the peritrichs to a higher taxonomic rank should be reconsidered.

Animals↗
PubMed1999

Phylogenetic relationships of orders within the class colpodea (Phylum ciliophora) inferred from small subunit rRNA gene sequences

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.

Journal Article↗
PubMed1981

A new macrosystem for the phylum Ciliophora doflein, 1901.

A new macrosystem for the phylum Ciliophora is described. It is based primarily on the concept of the structural conservatism of the cortical fibrillar structures. Three subphyla, the Postciliodesmatophora, Rhabdophora, and Cyrtophora, are described. These three subphyla are divided respectively into the following classes: (1) the Postciliodesmatophora, into the Karyorelictea and Spirotrichea; (2) Rhabdophora, into the Prostomea and the Litostomea n, nov.; and (3) Cyrtophorea, into the Nassophorea n. nov., Phyllopharyngea, Coipodea, and Oligohymenophorea. The subclass divisions of these eight classes are briefly discussed. Problem areas are indicated where further research will test the relationship proposed by this new macrosystem.

Animals↗