Cold-induced elongation and division in radicle cells of Pirus Malus embryos

1990 ◽  
Vol 68 (11) ◽  
pp. 2381-2388
Author(s):  
Mercedes Real ◽  
Michelle Bouvier-Durand
Keyword(s):  
Cell Cycle ◽  
Key Words ◽  
Cold Treatment ◽  
Nuclear Size ◽  
Radicle Growth ◽  
Granular Component ◽  
Nuclear Activation ◽  
Specific Event ◽  
Embryo Dormancy

Mitoses and elongation occurred concomitantly during the first days of germination in apple (Pirus Malus L.) radicle cells only when embryos were previously cold stimulated. The radicle cells in nonstimulated embryos did not elongate or enter the S, G2, and M phases of the cell cycle (the 2C level was estimated to 5 pg per nucleus). Accordingly, nuclear areas did not increase in the absence of cold treatment, whereas they doubled in size when embryos were cold stimulated and cultured to germinate. This increase in nuclear size can be considered a specific event in the pathway to germination. In nonstimulated embryos, nucleoli did not exhibit vacuolation and did not develop a granular component as they did in the germinating embryos after 3 days. Ultrastructural aspects of the chromatin itself were difficult to correlate with germination, since nuclei remained relatively homogeneous in structure during this process as well as during the breaking of dormancy. Key words: Radicle growth, embryo dormancy, microspectrophotometry, cell cycle, nuclear activation, ultrastructure.

Dormancy of apple embryos. Are starch and reserve protein changes related to dormancy breaking?

1984 ◽  
Vol 62 (11) ◽  
pp. 2308-2315 ◽  
Author(s):  
Michelle Bouvier-Durand ◽  
Alina Dawidowicz-Grzegorzewska ◽  
Claudine Thévenot ◽  
Daniel Come
Keyword(s):  
Cold Treatment ◽  
Moderate Temperature ◽  
The Other ◽  
Cold Stratification ◽  
Dormancy Release ◽  
Dormancy Breaking ◽  
Germination Process ◽  
Embryo Dormancy ◽  
Reserve Protein ◽  
Apple Seeds

During cold stratification of apple seeds both dormancy removal and initiation of the germination process occur. To characterize these two processes and to dissociate them from each other, two different cold treatments were used. One of them (cold treatment within the fruits) excluded the germination process, the other corresponded to classical stratification. Control treatments at moderate temperature were also applied. Starch accumulated in the radicle during breaking of embryo dormancy by stratification, whereas it disappeared when dormancy was broken inside the fruits. The comparison of starch changes at 0 and at 20 °C also showed that these changes cannot be related to dormancy release. Moreover, no proteolysis occurred whether dormancy was broken or not. Proteolysis observed during stratification of the embryos seemed to be linked to their imbibition (the first step of the germination). These data refute previous observations on this problem; they demonstrate that neither starch variations nor reserve protein changes can be related to breaking of embryo dormancy.

Sex Chromatin, Nuclear Size and the Cell Cycle

1967 ◽  
Vol 6 (2) ◽  
pp. 120-144 ◽  
Author(s):  
D.E. Comings
Keyword(s):  
Cell Cycle ◽  
Nuclear Size ◽  
Sex Chromatin

Effects of clipping and nitrogen fertilization on tiller development and flowering in Kentucky bluegrass

1993 ◽  
Vol 73 (2) ◽  
pp. 569-575 ◽  
Author(s):  
D. J. Thompson ◽  
K. W. Clark
Keyword(s):  
Key Words ◽  
Nitrogen Fertilization ◽  
Poa Pratensis ◽  
Cold Treatment ◽  
Kentucky Bluegrass ◽  
Shoot Density ◽  
Stem Length ◽  
Seed Harvest ◽  
Seed Field

One hundred cores (10 × 10 × 12 cm) of Kentucky bluegrass (Poa pratensis L. ’Nugget’) were removed from an established seed field, potted, and subjected to two clipping treatments after seed harvest (clipping at 2.5 cm to simulate straw and mechanical stubble removal and clipping at 7.5 cm to simulate straw removal) and two fertilizer treatments (solutions with and without the equivalent of 100 kg ha−1 of N). The plants were then subjected to a cold treatment (98 d at 2.5 °C) to induce flowering. Added N increased the number of large tillers formed before the cold treatment, and produced similar increases in the number of initiated tillers and flowering shoots. Added N resulted in larger inflorescences with more spikelets. Close clipping (2.5 cm) did not affect tillering or flowering shoot density, but reduced stem length and resulted in smaller inflorescences with fewer spikelets. Key words: Kentucky bluegrass, nitrogen, clipping height, tillering and flowering

Cell-cycle, protein content, and nuclear size in acute myeloid leukemia

Cytometry ◽  
1985 ◽  
Vol 6 (1) ◽  
pp. 47-53 ◽  
Author(s):  
M. Ffrench ◽  
P. A. Bryon ◽  
D. Fiere ◽  
H. Vu Van ◽  
O. Gentilhomme ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Acute Myeloid Leukemia ◽  
Protein Content ◽  
Myeloid Leukemia ◽  
Nuclear Size ◽  
Cell Cycle Protein ◽  
Acute Myeloid

Localization of a 210-kDa microtubule-interacting protein in the yeast Saccharomyces cerevisiae

1992 ◽  
Vol 38 (2) ◽  
pp. 149-152 ◽  
Author(s):  
J. Hašek ◽  
J. Jochová ◽  
P. Dráber ◽  
V. Viklický ◽  
E. Streiblová
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Cell Cycle ◽  
Monoclonal Antibody ◽  
Plasma Membrane ◽  
Key Words ◽  
Budding Yeast ◽  
Yeast Saccharomyces Cerevisiae ◽  
Double Labeling ◽  
Interacting Protein ◽  
Cytoplasmic Microtubules

Using the monoclonal antibody MA-01, which recognizes a 210-kDa protein in cell-free extracts, spindle and cytoplasmic microtubules were visualized in budding yeast, Saccharomyces cerevisiae. In additional, a spot-like staining was found beneath the plasma membrane, revealing in part correlation with F-actin distribution. This pattern was common for cells of all cell-cycle stages. The interaction of the protein recognized by MA-01 with microtubules was confirmed in the double labeling with a polyclonal antitubulin antibody and by the sensitivity of intranuclear structures stained by MA-01 to the microtubule disrupting drug nocodazole. Key words: immunoblotting, immunofluorescence, microtubule-interacting protein, Saccharomyces cerevisiae.

Nuclear size, shape, and density in endometrial carcinoma

2004 ◽  
Vol 14 (1) ◽  
pp. 138-144
Author(s):  
J. Miller ◽  
J. P. Geisler ◽  
K. J. Manahan ◽  
H. E. Geisler ◽  
G. A. Miller ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Image Analysis ◽  
Endometrial Carcinoma ◽  
Optical Density ◽  
Nuclear Size ◽  
Prognostic Indicators ◽  
Depth Of Invasion ◽  
Prognostic Features ◽  
Entire Cell

ObjectiveThe authors, using image analysis, previously demonstrated nuclear size and summed optical density to be independent prognostic indicators of recurrence in patients with endometrial carcinoma. The same tumors were analyzed by studying the optical features in the G0–G1 peak to see if this changed the values found as well as their importance as prognostic features at greater than 5 years of follow-up.MethodsTumors from 74 consecutive patients, surgically treated, with endometrial cancer, were evaluated. Survival, depth of invasion, lymphvascular space invasion, FIGO stage, grade, histology were analyzed. DNA index, progesterone receptor status, as well as nuclear size (NUSZ), shape (NUSH), and summed optical density (NUSD) were evaluated. NUSZ, NUSH, and NUSD were quantified using image analysis.ResultsFifteen patients died from disease during the observation period of the study. Mean follow-up was 82 months with a median of 84 months. Forty-nine patients had stage I cancers, five stage II, 17 stage III, and three stage IV. NUSZ and NUSD were all significantly different between the original (entire cell cycle) and the re-measured (G0G1 only) values (both P < 0.001). Multivariate analysis showed both the original (P = 0.0001) and G0G1-only (P = 0.046) NUSZ and the original (P = 0.0002) and G0G1-only (P = 0.018) NUSD to be independent prognosticators of survival.ConclusionImage analysis is able to quantify cellular and nuclear parameters not otherwise quantifiable. NUSD and NUSZ correlated with traditional prognostic indicators, were demonstrated independent predictors of survival at over 5 years of follow-up. Although the re-measured NUSZ and NUSD from only the G0–G1 peak were significantly different from the original NUSZ and NUSD, they were not as valuable as prognostic factors. Nuclear size and summed optical density measured from the entire cell cycle are independent prognostic indicators of survival at greater than 5 years of follow-up. Measuring nuclear morphometric features in the G0–G1 peak only does not add any new prognostic information.

Effect of transfection manipulations on mouse cell cycle progression

1991 ◽  
Vol 69 (9) ◽  
pp. 665-669 ◽  
Author(s):  
Carol A. K. McBroom ◽  
Rose Sheinin
Keyword(s):  
Cell Cycle ◽  
Calcium Phosphate ◽  
Dna Synthesis ◽  
Key Words ◽  
Cell Cycle Progression ◽  
Mouse Cell ◽  
Temperature Sensitive ◽  
Cycle Progression ◽  
Cellular Dna ◽  
Duplication Cycle

BalB/C-3T3 mouse fibroblasts and a temperature-sensitive derivative, ts 2e, were transfected by the calcium phosphate-dimethyl sulphoxide procedure to examine the effect of this manipulation on cell cycle progression. Cells were synchronized by growth to confluence in the presence of [2-14C]thymidine to generally label cellular DNA, and then subcultured from the G0 state. Plasmid pSV3-neo or pSV2-neo DNA was added to cells at 24 h post-plating, at peak Sphase. At designated intervals prior to, during, and after the transfection procedure, cells were labelled with [methyl-H]thymidine for 1 h to monitor nascent DNA synthesis and thereby assess cell cycle position. In all experiments performed, irrespective of the time of DNA addition, the transfection manipulations resulted in a reproducible, transient interruption of cell cycle progression, of about 5 h, and manifested as a delay in movement across the subsequent G1–S interface. Thereafter, the cycle resumed normally. The results indicated that the temporal sequence of the cell duplication cycle is altered when cells are exposed to exogenous DNA:Ca3 (PO4)2.Key words: transfection, cell cycle progression.

scholarly journals Cell cycle-dependent changes in the dynamics of MAP 2 and MAP 4 in cultured cells.

1989 ◽  
Vol 109 (1) ◽  
pp. 211-223 ◽  
Author(s):  
J B Olmsted ◽  
D L Stemple ◽  
W M Saxton ◽  
B W Neighbors ◽  
J R McIntosh
Keyword(s):  
Cell Cycle ◽  
Cultured Cells ◽  
Cold Treatment ◽  
Light Level ◽  
Microtubule Associated Proteins ◽  
Interphase Cells ◽  
Associated Proteins ◽  
Cycle Dependent ◽  
And Control

To examine the behavior of microtubule-associated proteins (MAPs) in living cells, MAP 4 and MAP 2 have been derivatized with 6-iodoacetamido-fluorescein, and the distribution of microinjected MAP has been analyzed using a low light level video system and fluorescence redistribution after photobleaching. Within 1 min following microinjection of fluoresceinated MAP 4 or MAP 2, fluorescent microtubule arrays were visible in interphase or mitotic PtK1 cells. After cold treatment of fluorescent MAP 2-containing cells (3 h, 4 degrees C), microtubule fluorescence disappeared, and the only fluorescence above background was located at the centrosomes; microtubule patterns returned upon warming. Loss of microtubule immunofluorescence after nocodozole treatment was similar in MAP-injected and control cells, suggesting that injected fluorescein-labeled MAP 2 did not stabilize microtubules. The dynamics of the MAPs were examined further by FRAP. FRAP analysis of interphase cells demonstrated that MAP 2 redistributed with half-times slightly longer (60 +/- 25 s) than those for MAP 4 (44 +/- 20 s), but both types of MAPs bound to microtubules in vivo exchanged with soluble MAPs at rates exceeding the rate of tubulin turnover. These data imply that microtubules in interphase cells are assembled with constantly exchanging populations of MAP. Metaphase cells at 37 degrees C or 26 degrees C showed similar mean redistribution half-times for both MAP 2 and MAP 4; these were 3-4 fold faster than the interphase rates (MAP 2, t1/2 = 14 +/- 6 s; MAP 4, t1/2 = 17 +/- 5 s). The extent of recovery of spindle fluorescence in MAP-injected cells was to 84-94% at either 26 or 37 degrees C. Although most metaphase tubulin, like the MAPs, turns over rapidly and completely under physiologic conditions, published work shows either reduced rates or extents of turnover at 26 degrees C, suggesting that the fast mitotic MAP exchange is not simply because of fast tubulin turnover. Exchange of MAP 4 bound to telophase midbodies occurred with dynamics comparable to those seen in metaphase spindles (t1/2 = approximately 27 s) whereas midbody tubulin exchange was slow (greater than 300 s). These data demonstrate that the rate of MAP exchange on microtubules is a function of time in the cell cycle.

scholarly journals Nuclear size, nuclear pore number and cell cycle

Nucleus ◽  
2011 ◽  
Vol 2 (2) ◽  
pp. 113-118 ◽  
Author(s):  
Kazuhiro Maeshima ◽  
Haruki Iino ◽  
Saera Hihara ◽  
Naoko Imamoto
Keyword(s):  
Cell Cycle ◽  
Nuclear Size ◽  
Nuclear Pore ◽  
Pore Number

scholarly journals Shortening the Dormancy Period and Improving Germination in American Ginseng Seed

HortScience ◽  
1995 ◽  
Vol 30 (4) ◽  
pp. 867E-867
Author(s):  
Marilyn H.Y. Hovius ◽  
John T.A. Proctor ◽  
Richard Reeleder
Keyword(s):  
Primary Source ◽  
Growing Season ◽  
American Ginseng ◽  
Zygotic Embryos ◽  
Radicle Growth ◽  
Immature Zygotic Embryos ◽  
Period Increase ◽  
Dormancy Period ◽  
Embryo Dormancy ◽  
Percent Germination

American ginseng seed is important as the primary source of propagation. Little is known about ginseng seed stratification and germination. The green seeds are harvested in August/September and stratified in boxes outdoors for 12 to 14 months. Then the after-ripened seeds are field-seeded; they germinate in the spring. Ginseng seeds undergo long dormancy periods caused by embryo dormancy and impermeable seedcoats. The objectives of this research are to shorten the dormancy period, increase the percent germination, and study the changes that occur during stratification using growth regulator and temperature treatments. Seeds stored at 15C from harvest to January and treated with 1000 ppm gibberellic acid (GA3) resulted in the most embryo growth, highest percent germination, and best growth after one growing season compared to 20C and no GA3. Tissue culturing immature zygotic embryos showed a requirement for GA3 (3–5 μM). Radicle growth may need an attached suspensor for development.

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