Effect of water extract from leaves of Nerium oleander L. on mitosis

The effect of water extract from leaves of Nerium oleander L. on the mitosis in meristematic cells of Allium cepa L. root tips has been studied. Observations were made on the changes during incubation and postincubation. Significant disturbances were observed in the development of the mitotic spindle leading to the formation of polyploid and hypoploid nuclei capable of further division. Substances contained in the water extract, and causing the disturbances, are water soluble glycosides. Introductory observations under an electron microscope indicate that the glycosides desorganize the continuous fibres of the spindle which can be considered as the direct cause of the observed disturbances.

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Relations between ultrastructure of mitotic spindle and chromosome translocation

Acta Societatis Botanicorum Poloniae ◽

10.5586/asbp.1981.080 ◽

2014 ◽

Vol 50 (4) ◽

pp. 585-594

Author(s):

Jadwiga A. Tarkowska

Keyword(s):

Electron Microscope ◽

Mitotic Spindle ◽

Light Microscope ◽

Chromosome Translocation ◽

Water Soluble ◽

Nerium Oleander ◽

Submicroscopic Structure ◽

Chromosome Arrangement

Dividing endosperm cells of Haemanthus katherinae Bak. treated with an 0.25 per cent mixture of water-soluble glycosides from Nerium oleander were insepected in a light microscope (LM) and severe disturbances were found in all phases of mitosis. The same cells were observed in the electron microscope (EM) and relations were noted and analysed between the chromosome arrangement and the submicroscopic structure of the mitotuc spindle. The successive steps in the disintegration of the formed spindle are described: fragmentatiun of all microtubules (MTs) starting from the poles, disappearance of non-kinetachore MTs and further the external MTs of the kineto,chore bundle. The central (internal) parallel ones remain the longest at the kinerf,ochares. Oleander glycosides cause disintegration of the existing MTs and prevent formation of new ones. The causes of restitution transformations in the successive phases of mitosis are discussed.

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The preprophase band: possible involvement in the formation of the cell wall

Journal of Cell Science ◽

10.1242/jcs.22.2.403 ◽

1976 ◽

Vol 22 (2) ◽

pp. 403-411 ◽

Cited By ~ 1

Author(s):

M.J. Packard ◽

S.M. Stack

Keyword(s):

Cell Wall ◽

Allium Cepa ◽

Cell Walls ◽

Preprophase Band ◽

Adjacent Cell ◽

Root Tips ◽

Meristematic Cells ◽

Narrow Region ◽

The Matrix

Numerous vesicles were observed among the microtubules of the “preprophase” band in prophase cells from root tips of Allium cepa. The content of these vesicles looks similar to the matrix of adjacent cell walls, and these vesicles often appear to be involved in exocytosis. In addition, the cell walls perpendicular to the plane of (beneath) the preprophase band are often differentially thickened compared to the walls lying parallel to the plane of the band. Our interpretation of these observations is that the preprophase band may direct or channel vesicles containing precursors of the cell wall to localized regions of wall synthesis. The incorporation of constituents of the cell wall into a narrow region defined by the position of the preprophase band may be a mechanism that ensures unidirecitonal growth of meristematic cells.

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Influence of extract from shoots of Taxus baccata var. elegantissima on ultrastructure and tubulin cytoskeleton of meristematic cells of Allium cepa L. roots

Acta Societatis Botanicorum Poloniae ◽

10.5586/asbp.2002.025 ◽

2014 ◽

Vol 71 (3) ◽

pp. 211-221 ◽

Cited By ~ 1

Author(s):

Agnieszka Majewska ◽

Mirosława Furmanowa ◽

Kazimierz Głowniak ◽

Joanna Guzewska ◽

Alicja Zobel ◽

...

Keyword(s):

Allium Cepa ◽

Chromatin Condensation ◽

Preprophase Band ◽

Taxus Baccata ◽

Cell Nuclei ◽

Root Tips ◽

Meristematic Cells ◽

Allium Cepa L ◽

Interphase Cells ◽

Average Size

We investigated the influence of extract from Taxus baccata var. Elegantissima (TbE) shoots in 1:8 dilution, containing paclitaxel in concentration of 81,6 µg/g fresh mass on ultrastructure and tubulin cytoskeleton of meristematic cells of Allium cepa L. root tips. Incubation time 3, 6, 12 and 24 h was followed with postincubation in water for 12 and 24 h. During shorter incubation (till 12 h) the surface of the cell nuclei decreased and chromatin became condensed (in comparison to control) but after 24 h the average surface increased and chromatin condensation decreased. In the course of incubation the average size of plastids and vacuoles increased. Moreover, after treatment mitochondria and plastids showed degradation of ultrastructure, which was reversed after 12 h of postincubation. Immunocytochemical assays demonstrated that in the course of incubation in the ThE extract, the tubulin cytoskeleton became partially disorganised. In most interphase cells, cortical microtubules (MTs) lost their oval transverse orientation. The preprophase band (PPB) position in the cell was often asymmetrical. The MTs array of the karyokinetic spindle and phragmoplast was also disturbed. These alterations were completely reversed during postincubation.

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Sodium cacodylate as antimitotic agent

Acta Societatis Botanicorum Poloniae ◽

10.5586/asbp.1988.032 ◽

2014 ◽

Vol 57 (3) ◽

pp. 329-340

Author(s):

Jadwiga A. Tarkowska

Keyword(s):

Allium Cepa ◽

Mitotic Spindle ◽

Sodium Cacodylate ◽

Antimitotic Agent ◽

Ultrastructural Studies ◽

Meristematic Cells ◽

Cacodylate Buffer ◽

Root Meristematic Cells ◽

Dividing Cells

The effect of pure sodium cacodylate on dividing cells was studied. The root meristematic cells of Allium cepa L. (the roots were squashed in acetoorcein) and endosperm cells of Haemanthus katherinae Bak. (in vitro observations) were used. Serious disturbances in karyokinesis and cytokinesis were found that led most often to the formation of polyploid or multinucleate (A. cepa) cells. These results point to damage of the mitotic spindle and phragmoplast. Careful use of cacodylate buffer in ultrastructural studies of microtubules is advised.

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Influence of hypoxia on protoplast structure in the plant cell

Acta Societatis Botanicorum Poloniae ◽

10.5586/asbp.1975.033 ◽

2015 ◽

Vol 44 (3) ◽

pp. 369-376

Author(s):

Maria Podbielkowska ◽

Bożena Borys

Keyword(s):

Endoplasmic Reticulum ◽

Nucleic Acids ◽

Allium Cepa ◽

Plant Cell ◽

Rough Endoplasmic Reticulum ◽

Sodium Azide ◽

Root Tips ◽

Respiratory Inhibitors ◽

Meristematic Cells ◽

Parallel Structures

An influence of hypoxia on the protoplast’s structure in the root tips meristematic cells of onion (Allium cepa L.) and of Tradescantia bracteata Small has been investigated. Hypoxia was caused either by respiratory inhibitors (sodium azide, 2,4-dinitrophenol), phosfon-D or by anaeroibic conditions. In both cases characteristic membranization of cytoplasm was observed. It appeared as spherical and parallel structures of rough endoplasmic reticulum. The observed hypertrophy was not connected with the increase of nucleic acids and proteins synthesis. In the examined cells the membranization was accompanied by an increase of the lipids content.

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Effects of water soluble oncostatic fraction from Rheum officinale Baill. rhizomes on Allium cepa root meristem. III. Morphological changes in cytoplasm

Acta Societatis Botanicorum Poloniae ◽

10.5586/asbp.1976.040 ◽

2015 ◽

Vol 45 (4) ◽

pp. 453-458

Author(s):

A. Dawidowicz-Grzegorzewska

Keyword(s):

Allium Cepa ◽

Metabolic Activity ◽

Light Microscope ◽

Root Meristem ◽

Morphological Changes ◽

Root Apex ◽

Water Soluble ◽

Prolonged Treatment ◽

Defence Reaction ◽

Meristematic Cells

Spiral concentric and linear configurations of membraneous structures were observed in the cytoplasm of fixed meristematic cells from the root apex of Allium cepa under the light microscope. They appeared after incubation in sublethal and lethal conditions in Rheum ofiicinale rhizome extracts. During postincubation these structures disappeared. They were interpreted as ER membranes. On the basis of literature data the physiological significance of these structures is discussed. It would seem that they are an indication of enhanced metabolic activity evoked either exogenously by various injuries as a form of defence reaction of the protoplast or endogenously during cytodifferentiation. Prolonged treatment in ,noxious conditions causes the ER membranes to transform into inactive myelin structures

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Cytological effects of medicinal plants in Qatar. II. Mitotic effect of water extract of Teucrium pilosum on Allium cepa.

CYTOLOGIA ◽

10.1508/cytologia.45.57 ◽

1980 ◽

Vol 45 (1/2) ◽

pp. 57-64 ◽

Cited By ~ 6

Author(s):

A. S. Shehab

Keyword(s):

Medicinal Plants ◽

Allium Cepa ◽

Water Extract ◽

Effect Of Water

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Effects of water soluble oncostatic fraction from Rheum officinale Baill. rhizomes on Allium cepa root meristem. I. The mitotic activity

Acta Societatis Botanicorum Poloniae ◽

10.5586/asbp.1976.038 ◽

2015 ◽

Vol 45 (4) ◽

pp. 429-443

Author(s):

A. Dawidowicz-Grzegorzewska

Keyword(s):

Allium Cepa ◽

Root Meristem ◽

Soluble Fraction ◽

Water Soluble ◽

Total Water ◽

Lower Intensity ◽

Interphase Nuclei ◽

Meristematic Cells ◽

Dna And Rna ◽

Inhibition Of Dna Synthesis

The effects of the oncostatic extracts from Rheum officinale rhizomes on the activity of meristematic cells from Allium cepa roots were investigated. A statistically significant decrease of the IM value was noted as well as of the total number of mitoses during incubation. The disturbances in the course of mitosis and cytokinesis are described and discussed. The kind of disturbances during postincubation points to damage of the S and G2 phases of the interphase nuclei. Cytochemical and autoradiographic studies demonstrated a diminished intensity of staining of DNA and RNA and inhibition of DNA synthesis during incubation, this leading in tum to a lower intensity of protein staining in postincubation. Disturbances in mitosis and cytokinesis after treatment wth 2,6-dihydroxyantraquinone, supposed to be the antimitotically active compound of the extract, are the same as those produced by the total water soluble fraction.

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