Microtubules and Microfilaments as Major Components of a Phagocytic Apparatus: the Cytopharyngeal Basket of the Ciliate Pseudomicrothorax dubius

Hausmann, Klaus; Peck, Robert K.

doi:10.1111/j.1432-0436.1978.tb00979.x

Cited by 39 publications

(18 citation statements)

References 12 publications

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“…while types I and 111 occur in other ciliate orders (5,32). The function of microtubule ribbons is probably guidance and transport of food during ingestion (24)(25)(26)(43)(44)(45) and their role in the ophryoscolecids is discussed elsewhere (1 [8][9][10][11][12][13][14][15][16][17][18][19][20].…”

Section: Resultsmentioning

confidence: 99%

The Functional and Evolutionary Significance of the Ultrastructure of the Ophryoscolecidae (Order Entodiniomorphida)¹

Furness

Butler

1988

The Journal of Protozoology

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ABSTRACT. Ophryoscolecid ciliates from the order Entodiniomorphida show a series of morphological types which have been interpreted as an evolutionary lineage. In this study, ultrastructural information from three species—the ancestral Entodinium, intermediate Eudiplodinium maggii, and the advanced Epidinium—has been evaluated in terms of ophryoscolecid evolution. The infraciliature, nuclei, contractile vacuoles, cortex, and cytoplasm are all very similar and sometimes indistinguishable among the three species, suggesting a close relationship. The cytoalimentary system, however, shows considerable interspecific variation. The cytopharynx differs in position and extent of microtubules and microfilaments, varying in appearance from a microtubular to a microfilament‐based mechanism while retaining similar component structures. The esophagus, a zone of cytoplasm extending from the cytopharynx and delimited by a microtubular/fibrillar wall, is rudimentary in Entodinium, sac‐like in Eudiplodinium, and tube‐like in Epidinium, where it also has convoluted walls and a sheath of fibrous material that suggest an expansible‐contractile structure. These variations have been related to type of food particle ingested. The capability of the cytoalimentary systems seems to be increased so that the more advanced forms can exploit a food resource, in the form of large plant fragments in the ruminal fluid, not available to the simpler, ancestral forms, which tend to ingest small particles such as bacteria and starch grains. The original evolutionary lineage based on morphological studies using light microscopy is supported by our observations, in these three forms, of ultrastructural variations in the cytopharynx and in their relationship with diet via possible ingestion mechanisms. Additional support for this evolutionary analysis comes from preliminary studies of other ophryoscolecids in which the cytoalimentary organization is consistent with their positions relative to one another in the evolutionary scheme.

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Section: Resultsmentioning

confidence: 99%

The Functional and Evolutionary Significance of the Ultrastructure of the Ophryoscolecidae (Order Entodiniomorphida)¹

Furness

Butler

1988

The Journal of Protozoology

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“…dubius ingests filamentous blue-green algae using its tube-shaped cytopharyngeal basket, the walls of which are made up of 20-25 rods (nemadesmata) composed of tightly packed microtubules (Fig. 2a, b, c, f, 9). During phagocytosis the nemadesmal lamellae, sheet-like rows of single microtubules each connected to a nemadesmos (Fig.…”

Section: Resultsmentioning

confidence: 99%

“…The culture of Pseudomicrothorax dubius and the conventional electron microscopic techniques used are described elsewhere [9,151. ATPase activity was demonstrated with a technique originally developed by Sundstrom and Mornstad [20] and modified as follows: Cells were collected by gentle centrifugation and fixed in an ice bath in 2% formaldehyde (freshly prepared from paraformaldehyde at 70" C in a water bath) with or without 1% glutaraldehyde for 5-20min.…”

Section: Methodsmentioning

confidence: 99%

Electron Microscopic Localization of ATPase Activity in the Cytopharyngeal Basket of the Ciliate Pseudomicrothorax dubius

Hauser

Hausmann

1982

Differentiation

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“…A strain of unidentified species of cyanobacterium Phormidium named Ph2 in our previous papers (Fiałkowska & Pajdak‐Stós, , ) and clones of Pseudomicrothorax dubius, Furgasonia blochmanni, Euplotes octocarinatus and rotifer Philodina roseola were used in the experiments. The ciliates P. dubius and F. blochmanni are highly specialised in feeding on filamentous Cyanobacteria , thanks to special oral apparatus called cythopharygeal basket (Hausmann & Peck, ; Vigues et al ., ). Euplotes octocarinatus feeds on unicellular algae and bacteria, but never on filamentous Cyanobacteria .…”

Section: Methodsmentioning

confidence: 99%

Chemical and mechanical signals in inducingPhormidium(Cyanobacteria) defence against their grazers

Fiałkowska

Pajdak‐Stós

2014

FEMS Microbiol Ecol

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The nature of stimuli evoking cyanobacterium defence was investigated in experiments on Phormidium sp. strain able to defend itself against ciliate grazers. Limited dispersion of trichomes in reaction to Pseudomicrothorax dubius separated from cyanobacterium with a mesh insert indicates the existence of a chemical cue originating from the ciliates. Grazers released into the wells where trichomes' dispersion was already limited by the cue initially had no difficulty finding food, but started to starve 24 h later. Similar situation was observed in control wells. Direct observations of trichomes attacked by the ciliates showed a distinct difference between the trichomes previously subjected to mesh-separated ciliate and the control ones. The former withdrew more frequently into a rigid sheath, whereas the latter usually withdrew into elastic tubes. This suggests that both chemical and mechanical stimuli are necessary to express cyanobacterium defence to the fullest extent. Further investigations showed that ciliates specialised in ingesting filamentous Cyanobacteria limit trichomes' dispersion, whereas filter-feeding Euplotes and Cyanobacteria-feeding rotifer do not. The cyanobacterium can detect grazer presence even without direct contact and modify its morphology in a way enabling full expression of defence reaction. This is the first report on ciliate-cyanobacterium chemical mediation.

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Microtubules and Microfilaments as Major Components of a Phagocytic Apparatus: the Cytopharyngeal Basket of the Ciliate Pseudomicrothorax dubius

Cited by 39 publications

References 12 publications

The Functional and Evolutionary Significance of the Ultrastructure of the Ophryoscolecidae (Order Entodiniomorphida)¹

The Functional and Evolutionary Significance of the Ultrastructure of the Ophryoscolecidae (Order Entodiniomorphida)¹

Electron Microscopic Localization of ATPase Activity in the Cytopharyngeal Basket of the Ciliate Pseudomicrothorax dubius

Chemical and mechanical signals in inducingPhormidium(Cyanobacteria) defence against their grazers

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Microtubules and Microfilaments as Major Components of a Phagocytic Apparatus: the Cytopharyngeal Basket of the Ciliate Pseudomicrothorax dubius

Cited by 39 publications

References 12 publications

The Functional and Evolutionary Significance of the Ultrastructure of the Ophryoscolecidae (Order Entodiniomorphida)1

The Functional and Evolutionary Significance of the Ultrastructure of the Ophryoscolecidae (Order Entodiniomorphida)1

Electron Microscopic Localization of ATPase Activity in the Cytopharyngeal Basket of the Ciliate Pseudomicrothorax dubius

Chemical and mechanical signals in inducingPhormidium(Cyanobacteria) defence against their grazers

Contact Info

Product

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The Functional and Evolutionary Significance of the Ultrastructure of the Ophryoscolecidae (Order Entodiniomorphida)¹

The Functional and Evolutionary Significance of the Ultrastructure of the Ophryoscolecidae (Order Entodiniomorphida)¹