Of the permanent structures revealed by 12G9 immunofluorescence, modifications of the oral crescent (OC) are associated with prior modifications in the development of basal body-containing structures in the secondary oral apparatus. Further, this labeling has shown that the postoral meridional filament is often expressed and the apical band is frequently interrupted on the mid-dorsal surface of janus cells irrespective of whether or not these cells express a "secondary" oral apparatus. 12G9-immunolabeling of janus cells has revealed additional phenotypes, including disorder of ciliary rows. The principal antibody employed, FXXXIX-12G9, immunolabels both transient cortical structures not directly associated with basal bodies (the fission line and the postoral meridional filament) and more permanent structures (apical band and oral crescent) that are associated with basal bodies. This reversal brings about frequent ectopic expression of ventral cortical landmarks, such as a "secondary" oral apparatus, on the dorsal surface. We have employed monoclonal antibodies to reinvestigate the janus mutants of the ciliate Tetrahymena thermophila, which cause reversal of circumferential polarity on the dorsal surface of the cell. The maternal band is reorganized earlier, simultaneously with the oral structure. The differentiation of the band is completed in the final stages of cytokinesis and in the young post-dividing cell. In the posterior daughter cell, the new apical band originates as small clusters of filaments located at the base of the anterior basal bodies of the apical basal body couplets during early anaphase. The labeling of the maternal oral crescent disappears in pre-metaphase cells and reappears during anaphase, concomitantly with differentiation of the new structure in the posterior daughter cell. We followed the sequence of development of these structures during divisional morphogenesis. In Tetrahymena interphase cells, mAb 12G9 localizes to the sites of basal bodies and to the striated ciliary rootlets, to the apical band of filaments and to the fine fibrillar oral crescent. This investigation deals with immunolocalization using light and electron microscopy of filaments labeled by the monoclonal antibody 12G9, which in other ciliates identifies filaments involved in transmission of cellular polarities and marks cell meridians with the highest morphogenetic potential. and Lara, E.: COI Barcoding of Nebelid Testate Amoebae (Amoebozoa: Arcellinida): Extensive Cryptic Diversity and Redefinition of the Hyalospheniidae Schultze – Protist 163, issue 3, 415-434, 2012.The ciliate Tetrahymena thermophila possesses a multitude of cytoskeletal structures whose differentiation is related to the basal bodies the main mediators of the cortical pattern. It is distinguished from the above mentioned species by the presence of wavy lateral margins. Remarks: Nebela meisterfeldi resembles N. The aperture is oval, surrounded by a very thin collar of organic cement.ĭimensions: Length 147-160 µm, breadth 69-85 µm, diameter of aperture 37-42 µm (n=6).Įcology: Sphagnum mosses in a peatland in Strathcona Park, Vancouver Island and from aquatic mosses at the border of a small stream in Grouse Mountain, British Columbia, Canada. Shell composed of small particles likely obtained from preys (i.e. Granoreticulose – Naked amoeboid organisms with branched filopodia over which numerous granules move extremely quickly in both directions and which can form an extensive network (reticulum).ĭiagnosis: The shell is acrostome, elongated pyriform, laterally slightly compressed, with wavy lateral margin, brownish in color.Pseudopodia usually appressed to the substratum. Granules are evenly distributed and move slowly or not at all. Granofilose – Naked amoeboid organisms with granular filose pseudopodia. Filose – Naked amoeboid organisms with filamentous pseudopodia.Some species have subpseudopodia, small extensions of a hyaline anterior zone. Lobose – Naked amoebae with finger-shaped, tubular pseudopodia.Granuloreticulose – Testate amoeboid organisms with branched filopodia over which numerous grains move extremely quickly in both directions and which can form an extensive network (reticulum).Test and pseudopodia appressed to the substratum. Granofilose – Testate amoeboids with granular filose pseudopodia.Filose – Testate amoebae with filose (filamentous) pseudopodia.Lobose – Testate amoebae with finger-shaped, tubular pseudopodia.
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