Life After Secretion—Yersinia enterocolitica Rapidly Toggles Effector Secretion and Can Resume Cell Division in Response to Changing External Conditions

VII. Further experiments and histological investigations on intumescences, with some observations on nuclear division in pathological tissues

Philosophical Transactions of the Royal Society of London Series B Containing Papers of a Biological Character (1896-1934) ◽

10.1098/rstb.1906.0007 ◽

1906 ◽

Vol 198 (239-250) ◽

pp. 221-263 ◽

Cited By ~ 1

Keyword(s):

Cell Division ◽

Nuclear Division ◽

The Other ◽

No Formation ◽

Other Hand ◽

External Conditions ◽

Stems And Leaves ◽

Pathological Tissues

In a paper published in 1900 a description was given of certain pathological outgrowths, first called intumescences by Sorauer, but known as œdemata to American writers, occurring spontaneously on Hibiscus vitifolius , Linn. The paper is mainly anatomical , and the various modifications of intumescences found on the stems and leaves are described. On the stem the outgrowths originate by cell division, which is followed by the elongation of the cells concerned. At a later stage the stem intumescence is cut off by cork, so that the cells above the layer of cork die and collapse. In leaf intumescences there is less cell division and no formation of cork. Preliminary experiments were made to determine the conditions under which intumescences arise, and showed the importance of changes in the external conditions in connection with the question of the formation of outgrowths. Strong and healthy plants, grown in the open air , did not develop intumescences, nor did very weakly plants grown in a cool and poorly lighted, though damp, greenhouse. On the other hand, plants grown in warm, damp, well-lighted greenhouses produced intumescences in varying number and degree.

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The Ultrastructure of the Nuclear Events of Binary Fission in Paramecium bursaria and the Effects of Colchicine on Cell Division

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100051396 ◽

1974 ◽

Vol 32 ◽

pp. 276-277

Author(s):

L. M. Lewis

Keyword(s):

Cell Division ◽

Nuclear Envelope ◽

Condensed Chromatin ◽

Binary Fission ◽

Paramecium Bursaria ◽

Nuclear Events ◽

Division Axis

The effects of colchicine on extranuclear microtubules associated with the macronucleus of Paramecium bursaria were studied to determine the possible role that these microtubules play in controlling the shape of the macronucleus. In the course of this study, the ultrastructure of the nuclear events of binary fission in control cells was also studied.During interphase in control cells, the micronucleus contains randomly distributed clumps of condensed chromatin and microtubular fragments. Throughout mitosis the nuclear envelope remains intact. During micronuclear prophase, cup-shaped microfilamentous structures appear that are filled with condensing chromatin. Microtubules are also present and are parallel to the division axis.

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Stimulated Virus Production in Vinblastine and Cytochalasin-Induced Multinucleate Cells

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100067923 ◽

1970 ◽

Vol 28 ◽

pp. 186-187

Author(s):

Krishan Awtar

Keyword(s):

Cell Division ◽

Normal Cell ◽

Virus Production ◽

Multinucleate Cells ◽

Daughter Cells ◽

Cell Divisions ◽

Nuclear Membranes ◽

Division 2 ◽

Vinblastine Sulfate

Exposure of cells to low sublethal but mitosis-arresting doses of vinblastine sulfate (Velban) results in the initial arrest of cells in mitosis followed by their subsequent return to an “interphase“-like stage. A large number of these cells reform their nuclear membranes and form large multimicronucleated cells, some containing as many as 25 or more micronuclei (1). Formation of large multinucleate cells is also caused by cytochalasin, by causing the fusion of daughter cells at the end of an otherwise .normal cell division (2). By the repetition of this process through subsequent cell divisions, large cells with 6 or more nuclei are formed.

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Confocal microscopy of the cytoskeleton in living plant cells following microinjection of fluorescent probes

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100146497 ◽

1993 ◽

Vol 51 ◽

pp. 130-131

Author(s):

Ann Cleary

Keyword(s):

Cell Division ◽

Fluorescent Probes ◽

Actin Filaments ◽

Intracellular Transport ◽

Cell Structure ◽

Plant Cells ◽

Cell Plate ◽

Cell Cortex ◽

Living Plant ◽

Rhodamine Phalloidin

Microinjection of fluorescent probes into living plant cells reveals new aspects of cell structure and function. Microtubules and actin filaments are dynamic components of the cytoskeleton and are involved in cell growth, division and intracellular transport. To date, cytoskeletal probes used in microinjection studies have included rhodamine-phalloidin for labelling actin filaments and fluorescently labelled animal tubulin for incorporation into microtubules. From a recent study of Tradescantia stamen hair cells it appears that actin may have a role in defining the plane of cell division. Unlike microtubules, actin is present in the cell cortex and delimits the division site throughout mitosis. Herein, I shall describe actin, its arrangement and putative role in cell plate placement, in another material, living cells of Tradescantia leaf epidermis.The epidermis is peeled from the abaxial surface of young leaves usually without disruption to cytoplasmic streaming or cell division. The peel is stuck to the base of a well slide using 0.1% polyethylenimine and bathed in a solution of 1% mannitol +/− 1 mM probenecid.

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Electronmicroscopic localization of ribonucleic acids in ciliate Bursaria truncatella during cell division

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100158200 ◽

1990 ◽

Vol 48 (3) ◽

pp. 132-133

Author(s):

Vladimir Popenko ◽

Natalya Cherny ◽

Maria Yakovleva

Keyword(s):

Cell Division ◽

High Specificity ◽

Longitudinal Axis ◽

Gold Complexes ◽

Somatic Nucleus ◽

Ribonucleic Acids ◽

Biological Meaning ◽

Bivalent Cations ◽

Lowicryl K4m ◽

Short Time

Highly polyploid somatic nucleus (macronucleus) of ciliate Bursaria truncatella under goes severe changes in morphology during cell division. At first, macronucleus (Ma) condences, diminishes in size and turns perpendicular to longitudinal axis of the cell. After short time, Ma turns again, elongates and only afterwards the process of division itself occurs. The biological meaning of these phenomena is not clear.Localization of RNA in the cells was performed on sections of ciliates B. truncatella, embedded in “Lowicryl K4M” at various stages: (1) before cell division (Figs. 2,3); (11) at the stage of macronucleus condensation; (111) during elongation of Ma (Fig.4); (1111) in young cells (0-5min. after division). For cytochemical labelling we used RNaseAcolloidal gold complexes (RNase-Au), which are known to bind to RNA containing cell ularstructures with high specificity. The influence of different parameters on the reliability and reproducibility of labelling was studied. In addition to the factors, discussed elsewhere, we found that the balance of mono- and bivalent cations is of great significance.

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Centromere assembly and non-random sister chromatid segregation in stem cells

Essays in Biochemistry ◽

10.1042/ebc20190066 ◽

2020 ◽

Vol 64 (2) ◽

pp. 223-232 ◽

Cited By ~ 1

Author(s):

Ben L. Carty ◽

Elaine M. Dunleavy

Keyword(s):

Stem Cells ◽

Cell Division ◽

Cell Fate ◽

Sister Chromatid ◽

Asymmetric Cell Division ◽

Protein A ◽

Germline Stem Cells ◽

Sister Chromatids ◽

Centromere Protein A ◽

Oocyte Meiosis

Abstract Asymmetric cell division (ACD) produces daughter cells with separate distinct cell fates and is critical for the development and regulation of multicellular organisms. Epigenetic mechanisms are key players in cell fate determination. Centromeres, epigenetically specified loci defined by the presence of the histone H3-variant, centromere protein A (CENP-A), are essential for chromosome segregation at cell division. ACDs in stem cells and in oocyte meiosis have been proposed to be reliant on centromere integrity for the regulation of the non-random segregation of chromosomes. It has recently been shown that CENP-A is asymmetrically distributed between the centromeres of sister chromatids in male and female Drosophila germline stem cells (GSCs), with more CENP-A on sister chromatids to be segregated to the GSC. This imbalance in centromere strength correlates with the temporal and asymmetric assembly of the mitotic spindle and potentially orientates the cell to allow for biased sister chromatid retention in stem cells. In this essay, we discuss the recent evidence for asymmetric sister centromeres in stem cells. Thereafter, we discuss mechanistic avenues to establish this sister centromere asymmetry and how it ultimately might influence cell fate.

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