Uncoupling of basal body duplication and cell division in crochu, a mutant of Paramecium hypersensitive to nocodazole

Development ◽  
1998 ◽  
Vol 125 (7) ◽  
pp. 1305-1314
Author(s):  
M. Jerka-Dziadosz ◽  
F. Ruiz ◽  
F. Beisson
Keyword(s):  
Cell Division ◽  
Basal Body ◽  
Cell Shape ◽  
Surface Pattern ◽  
Recessive Mutation ◽  
Basal Bodies ◽  
Wild Type ◽  
In The Wild ◽  
Cortical Cytoskeleton ◽  
Do So

In Paramecium the development of cell shape and surface pattern during division depends on a precise spatial and temporal pattern of duplication of the ciliary basal bodies which are the organizers of the cortical cytoskeleton. According to their localization, basal bodies will duplicate once, more than once or not all and this duplication is coupled with cell division, as is centrosomal duplication in metazoan cells. We describe here a monogenic nuclear recessive mutation, crochu1 (cro1), resulting in abnormal cell shape and cortical pattern and hypersensitivity to nocodazole. The cytological analysis, by immunofluorescence and electron microscopy, demonstrates that the mutation causes hyper duplication of basal bodies and releases both spatial and temporal control of duplication as basal bodies continue to proliferate in interphase and do so at ectopic locations, beneath the surface and in cortical territories where no duplication occurs in the wild type. However, the abnormal surface organization of cro1 cells does not affect the program of basal body duplication during division. By genetic analysis, no interaction was detected with the sm19 mutation which impairs basal body duplication. In contrast, the cro1 mutation suppresses the nocodazole resistance conferred by nocr1, a mutation in a beta-tubulin gene. This interaction suggests that the primary effect of the mutation bears on microtubule dynamics, whose instability, normally increased during division, would persist throughout the interphase and provide a signal for constitutive basal body duplication.

Development of surface pattern during division in Paramecium. II. Defective spatial control in the mutant kin241

Development ◽  
1992 ◽  
Vol 115 (1) ◽  
pp. 319-335 ◽  
Author(s):  
M. Jerka-Dziadosz ◽  
N. Garreau de Loubresse ◽  
J. Beisson
Keyword(s):  
Basal Body ◽  
Major Effect ◽  
The Body ◽  
Cortical Reorganization ◽  
Surface Pattern ◽  
Recessive Mutation ◽  
Wild Type ◽  
Cortical Organization ◽  
Nuclear Reorganization ◽  
In The Wild

kin241 is a monogenic nuclear recessive mutation producing highly pleiotropic effects on cell size and shape, generation time, thermosensitivity, nuclear reorganization and cortical organization. We have analyzed the nature of the cortical disorders and their development during division, using various specific antibodies labelling either one of the cortical cytoskeleton components, as was previously done for analysis of cortical pattern formation in the wild type. Several abnormalities in basal body properties were consistently observed, although with a variable frequency: extra microtubules in either the triplets or in the lumen; nucleation of a second kinetodesmal fiber; abnormal orientation of the newly formed basal body with respect to the mother one. The latter effect seems to account for the major observed cortical disorders (reversal, intercalation of supplementary ciliary rows). The second major effect of the mutation concerns the spatiotemporal map of cortical reorganization during division. Excess basal body proliferation occurs and is correlated with modified boundaries of some of the cortical domains identified in the wild type on the basis of their basal body duplication pattern. This is the first mutant described in a ciliate in which both the structure and duplication of basal bodies and the body plan are affected. The data support the conclusion that the mutation does not alter the nature of the morphogenetic signal(s) which pervade the dividing cell, nor the competence of cytoskeletal structures to respond to signalling, but affects the local interpretation of the signals.

Development of surface pattern during division in Paramecium. I. Mapping of duplication and reorganization of cortical cytoskeletal structures in the wild type

Development ◽  
1989 ◽  
Vol 105 (2) ◽  
pp. 191-211 ◽  
Author(s):  
F. Iftode ◽  
J. Cohen ◽  
F. Ruiz ◽  
A.T. Rueda ◽  
L. Chen-Shan ◽  
...  
Keyword(s):  
Basal Body ◽  
Surface Pattern ◽  
Basal Bodies ◽  
Wild Type ◽  
Cell Level ◽  
Local Constraints ◽  
Whole Cell ◽  
Cortical Unit ◽  
Asymmetrical Pattern ◽  
In The Wild

The shape of a Paramecium is determined by the organization of its cortex which constitutes most of the cell cytoskeleton. These structures and networks are organized in relation to the approx. 4000 ciliary basal bodies present at the surface. Each basal body is the centre of a polarized and asymmetrical cortical unit. At the whole-cell level, all units are tandemly arranged in parallel rows and form a defined asymmetrical pattern with dorsoventral and anteroposterior polarities. During division, the cortex is the site of the major morphogenetic processes. In order to analyse how the surface pattern and the shape of the cell are reconstructed at each division, we have used specific immunological and cytological probes to map, in space and time, the reorganization of each of the major cytoskeletal cortical components: basal bodies and microtubules, kinetodesmal fibres, epiplasm and outer lattice. This cytological dissection demonstrates that the surface of the dividing cell is progressively invaded by morphogenetic waves which successively and individually trigger the duplication, assembly or reorganization of each structure and which all spread from the same epicentre (oral apparatus and fission furrow) with the same shape. Furthermore, the response of units to the morphogenetic waves depends on their position on the cell. It thus appears that despite the structural local constraints within units, the development of surface pattern is controlled in an integrated manner by transcellular signals.

Cytoskeletal discontinuities in the cell body cortex initiate basal body assembly and oral development in the ciliate Stentor

Development ◽  
1985 ◽  
Vol 87 (1) ◽  
pp. 249-257
Author(s):  
Nöel De Terra
Keyword(s):  
Cell Division ◽  
Cell Surface ◽  
Cell Body ◽  
Basal Body ◽  
Basal Bodies ◽  
Mass Assembly ◽  
Oral Development ◽  
Cortical Cytoskeleton

My previous work has shown that disconnecting the oral apparatus of Stentor into two parts induces mass assembly of basal bodies on the ventral cell surface and thus initiates oral development. This operation severs the extensive microtubule tracts joining the oral membranelles at their bases. To determine whether basal body assembly and oral development are also induced by permanently disconnecting the longitudinal microtubule fibre tracts (mt fibre tracts) of the cell body cortex, I interposed a ring of inverted (heteropolar) cortex between the anterior and posterior halves of interphase stentors. When successful, this operation made it impossible for these fibre tracts to rejoin at the heteropolar boundaries and always induced basal body assembly and oral development in the graft complex. By contrast, tripartite homopolar graft complexes rarely initiated oral development; when they did, it was apparently in response to the presence of disproportionately small oral structures, which is the normal stimulus for oral development in Stentor. The mt fibre tracts of tripartite homopolar grafts also eventually became continuous. These results support the hypothesis that permanent, extensive discontinuities anywhere within the cortical cytoskeleton can trigger basal body assembly and oral development. Since the onset of these processes is known to initiate cell division in Stentor, the results also suggest that development of discontinuities within the cortical cytoskeleton during interphase growth may be the endogenous stimulus initiating cell division in Stentor.

scholarly journals The ultrastructure of cell division in Euglena gracilis

1978 ◽  
Vol 31 (1) ◽  
pp. 25-35
Author(s):  
M.A. Gillott ◽  
R.E. Triemer
Keyword(s):  
Cell Division ◽  
Nuclear Envelope ◽  
Basal Body ◽  
Euglena Gracilis ◽  
Equatorial Region ◽  
Basal Bodies ◽  
Cleavage Furrow ◽  
Free Zone ◽  
Prophase Nucleus

The ultrastructure of mitosis in Euglena gracilis was investigated. At preprophase the nucleus migrates anteriorly and associates with the basal bodies. Flagella and basal bodies replicate at preprophase. Cells retain motility throughout division. The reservoir and the prophase nucleus elongate perpendicular to the incipient cleavage furrow. One basal body pair surrounded by a ribosome-free zone is found at each of the nuclear poles. The spindle forms within the intact nuclear envelope- Polar fenestrae are absent. At metaphase, the endosome is elongated from pole to pole, and chromosomes are loosely arranged in the equatorial region. Distinct, trilayered kinetochores are present. Spindle elongates as chromosomes migrate to the poles forming a dumb-bell shaped nucleus by telophase. Daughter nuclei are formed by constriction of the nuclear envelope. Cytokinesis is accomplished by furrowing. Cell division in Euglena is compared with that of certain other algae.

The cell division cycle of Trypanosoma brucei brucei : timing of event markers and cytoskeletal modulations

1989 ◽  
Vol 323 (1218) ◽  
pp. 573-588 ◽  
Keyword(s):  
Cell Cycle ◽  
Cell Division ◽  
Trypanosoma Brucei ◽  
Basal Body ◽  
Single Copy ◽  
Cell Division Cycle ◽  
Basal Bodies ◽  
Division Plane ◽  
Transmission Electron ◽  
Single Nucleus

We have analysed the timing and order of events occurring within the cell division cycle of Trypanosoma brucei . Cells in the earliest stages of the cell cycle possess a single copy of three major organelles: the nucleus, the kinetoplast and the flagellum. The first indication of progress through the cell cycle is the elongation of the pro-basal body lying adjacent to the mature basal body subtending the flagellum. This newly elongated basal body occupies a posterior position within the cell when it initiates growth of the new daughter flagellum. Genesis of two new pro-basal bodies occurs only after growth of the new daughter flagellum has been initiated. Extension of the new flagellum, together with the paraflagellar rod, then continues throughout a major portion of the cell cycle. During this period of flagellum elongation, kinetoplast division occurs and the two kinetoplasts, together with the two flagellar basal bodies, then move apart within the cell. Mitosis is then initiated and a complex pattern of organelle positions is achieved whereby a division plane runs longitudinally through the cell such that each daughter ultimately receives a single nucleus, kinetoplast and flagellum. These events have been described from observations of whole cytoskeletons by transmission electron microscopy together with detection of particular organelles by fluorescence microscopy. The order and timing of events within the cell cycle has been derived from analyses of the proportion of a given cell type occurring within an exponentially growing culture.

Role of f-box factor foxj1 in differentiation of ciliated airway epithelial cells

2004 ◽  
Vol 286 (4) ◽  
pp. L650-L657 ◽  
Author(s):  
Yingjian You ◽  
Tao Huang ◽  
Edward J. Richer ◽  
Jens-Erik Harboe Schmidt ◽  
Joseph Zabner ◽  
...  
Keyword(s):  
Epithelial Cell ◽  
Epithelial Cells ◽  
Basal Body ◽  
Ciliated Cell ◽  
Airway Epithelial Cells ◽  
Cell Phenotype ◽  
Basal Bodies ◽  
Airway Epithelial ◽  
Ciliated Cells ◽  
Wild Type

Factors required for commitment of an undifferentiated airway epithelial cell to a ciliated cell are unknown. Cell ultrastructure analysis indicates ciliated cell commitment activates a multistage program involving synthesis of cilia precursor proteins and assembly of macromolecular complexes. Foxj1 is an f-box transcription factor expressed in ciliated cells and shown to be required for cilia formation by gene deletion in a mouse model. To identify a specific role for foxj1 in directing the ciliated cell phenotype, we evaluated the capacity of foxj1 to induce ciliogenesis and direct cilia assembly. In a primary culture model of wild-type mouse airway epithelial cells, foxj1 expression preceded the appearance of cilia and in cultured foxj1 null cells cilia did not develop. Delivery of foxj1 to polarized epithelial cell lines and primary cultured alveolar epithelial cells failed to promote ciliogenesis. Similarly, delivery of foxj1 to wild-type airway epithelial cells did not enhance the total number of ciliated cells. In contrast, delivery of foxj1 to null cells resulted in the appearance of cilia. Analysis revealed that, in the absence of foxj1, null cells contained cilia precursor basal bodies, indicating prior commitment to ciliogenesis. However, the basal bodies were disorganized within the apical compartment and failed to dock with the apical membrane. Reconstitution of foxj1 in null cells restored normal basal body organization, resulting in axoneme growth. Thus foxj1 functions in late-stage ciliogenesis to regulate programs promoting basal body docking and axoneme formation in cells previously committed to the ciliated cell phenotype.

Evidence for the presence of DNA at basal body sites in Tetrahymena pyriformis

1965 ◽  
Vol 162 (989) ◽  
pp. 473-491 ◽  
Keyword(s):  
Cell Division ◽  
Basal Body ◽  
Mitotic Cycle ◽  
Tritiated Thymidine ◽  
Tetrahymena Pyriformis ◽  
Cell Cortex ◽  
Basal Bodies ◽  
Temperature Shock ◽  
Large Numbers ◽  
Order Of Magnitude

The reasons that have led to a search for DNA in the basal body of Tetrahymena pyriformis are twofold: the well-known property of proliferation of this organelle and the possibility that basal body DNA might be involved in its morphogenesis. After a brief review of earlier work the methods employed in this paper are described. To ensure large numbers of cells in a particular state of development organisms were grown in synchronized culture. Animals required for autoradiographic studies were appropriately treated with tritiated thymidine. All investigations were made on the cell cortex or 'ghost’ in order to avoid confusion from cell contents. In addition to autoradiography of ghosts, tests were made with acridine orange in the fluorescence microscope. It is concluded from fluorescence tests that basal bodies of T. pyriformis strain S contain DNA . This DNA is not detectable for the first 2h of the temperature-shock cycle, but is detect­able thereafter until cell division. The presence of DNA is confirmed by the autoradiography experiments. The amount of DNA per basal body is estimated very roughly in order of magnitude as 2 × 10 -16 g. The origin of basal body DNA is discussed and the possibilities and consequences of the existence of DNA in the homologous centriole are examined in terms of the mitotic cycle, the amoeba-flagellate transformation in Naegleria , and artificial parthenogenesis. The paper concludes with a brief discussion of the genetic implications of basal body DNA .

scholarly journals Branching of sporogenic aerial hyphae in sflA and sflB mutants of Streptomyces coelicolor correlates to ectopic localization of DivIVA and FtsZ in time and space

2020 ◽  
Author(s):  
Le Zhang ◽  
Joost Willemse ◽  
Paula Yagüe ◽  
Ellen de Waal ◽  
Dennis Claessen ◽  
...  
Keyword(s):  
Cell Division ◽  
Streptomyces Coelicolor ◽  
Constitutive Expression ◽  
Hyphal Growth ◽  
Lateral Wall ◽  
Specific Cell ◽  
Wild Type ◽  
Aerial Hyphae ◽  
In The Wild ◽  
Z Ring

ABSTRACTBacterial cytokinesis starts with the polymerization of the tubulin-like FtsZ, which forms the cell division scaffold. SepF aligns FtsZ polymers and also acts as a membrane anchor for the Z-ring. While in most bacteria cell division takes place at midcell, during sporulation of Streptomyces many septa are laid down almost simultaneously in multinucleoid aerial hyphae. The genomes of streptomycetes encode two additional SepF paralogs, SflA and SflB, which can interact with SepF. Here we show that the sporogenic aerial hyphae of sflA and sflB mutants of Streptomyces coelicolor frequently branch, a phenomenon never seen in the wild-type strain. The branching coincided with ectopic localization of DivIVA along the lateral wall of sporulating aerial hyphae. Constitutive expression of SflA and SflB largely inhibited hyphal growth, further correlating SflAB activity to that of DivIVA. SflAB localized in foci prior to and after the time of sporulation-specific cell division, while SepF co-localized with active septum synthesis. Foci of FtsZ and DivIVA frequently persisted between adjacent spores in spore chains of sflA and sflB mutants, at sites occupied by SflAB in wild-type cells. This may be caused by the persistance of SepF multimers in the absence of SflAB. Taken together, our data show that SflA and SflB play an important role in the control of growth and cell division during Streptomyces development.

scholarly journals Identification of a gene that shortens clonal life span of Paramecium tetraurelia.

Genetics ◽  
1989 ◽  
Vol 123 (4) ◽  
pp. 749-754 ◽  
Author(s):  
Y Takagi ◽  
K Izumi ◽  
H Kinoshita ◽  
T Yamada ◽  
K Kaji ◽  
...  
Keyword(s):  
Cell Division ◽  
Life Span ◽  
Recessive Mutation ◽  
Supporting Evidence ◽  
Paramecium Tetraurelia ◽  
Wild Type ◽  
Fission Rate ◽  
Cellular Life ◽  
Controlling Mechanism ◽  
Pleiotropic Gene

Abstract We have isolated a Paramecium tetraurelia mutant that divides slowly in daily reisolation cultures and repeats short clonal life spans after successive autogamies. Here we show, using breeding analysis, that a recessive mutation is responsible for the low fission rate and that this low rate is closely related to the short clonal life span. We conclude that a single pleiotropic gene controls these traits and have named it jumyo. In an attempt to further characterize the jumyo mutant, we have revealed that it has a culture life span similar to that of the wild-type cells and that, when mass cultured, it can divide as rapidly as wild-type cells. There was strong evidence that the mutant cells excreted into culture medium some substance that promotes their cell division. These findings may not only present supporting evidence for the hypothesis that the cellular life span is genetically programmed but also give a material basis for the study of the controlling mechanism of cell division in relation to the clonal life span.

scholarly journals Three-dimensional Organization of Basal Bodies from Wild-Type and δ-Tubulin Deletion Strains of Chlamydomonas reinhardtii

2003 ◽  
Vol 14 (7) ◽  
pp. 2999-3012 ◽  
Author(s):  
Eileen T. O'Toole ◽  
Thomas H. Giddings ◽  
J. Richard McIntosh ◽  
Susan K. Dutcher
Keyword(s):  
Chlamydomonas Reinhardtii ◽  
Basal Body ◽  
Electron Tomography ◽  
Three Dimensional ◽  
Specimen Preparation ◽  
Basal Bodies ◽  
Wild Type ◽  
Tubulin Isoforms ◽  
Striated Fiber ◽  
And Function

Improved methods of specimen preparation and dual-axis electron tomography have been used to study the structure and organization of basal bodies in the unicellular alga Chlamydomonas reinhardtii. Novel structures have been found in both wild type and strains with mutations that affect specific tubulin isoforms. Previous studies have shown that strains lacking δ-tubulin fail to assemble the C-tubule of the basal body. Tomographic reconstructions of basal bodies from the δ-tubulin deletion mutant uni3-1 have confirmed that basal bodies contain mostly doublet microtubules. Our methods now show that the stellate fibers, which are present only in the transition zone of wild-type cells, repeat within the core of uni3-1 basal bodies. The distal striated fiber is incomplete in this mutant, rootlet microtubules can be misplaced, and multiflagellate cells have been observed. A suppressor of uni3-1, designated tua2-6, contains a mutation in α-tubulin. tua2-6; uni3-1 cells build both flagella, yet they retain defects in basal body structure and in rootlet microtubule positioning. These data suggest that the presence of specific tubulin isoforms in Chlamydomonas directly affects the assembly and function of both basal bodies and basal body-associated structures.

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