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

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

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.

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

DNA Content and Size of Sex Chromatin Positive Female Nuclei During the Cell Cycle

1967 ◽  
Vol 6 (1) ◽  
pp. 1-19 ◽  
Author(s):  
H.P. Klinger ◽  
H.G. Schwarzacher ◽  
Jane Weiss
Keyword(s):  
Cell Cycle ◽  
Dna Content ◽  
Sex Chromatin

Epo/Epor Signaling Critically Regulates Maturation of the Primitive Erythroid Lineage In the Mammalian Embryo

Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 813-813
Author(s):  
Jeffrey Malik ◽  
James Palis
Keyword(s):  
Cell Cycle ◽  
Cell Size ◽  
Target Genes ◽  
Yolk Sac ◽  
Nuclear Size ◽  
Wild Type ◽  
Erythroid Progenitors ◽  
Mammalian Embryo ◽  
Transcript Levels ◽  
Erythroid Precursors

Abstract Abstract 813 Erythropoiesis in both the embryo and the adult is characterized by the progressive maturation of lineage-specific progenitors through morphologically identifiable precursors that enucleate to form mature erythrocytes. In the adult, erythropoietin (Epo) binds its homodimeric receptor (EpoR) and activates the Jak2-Stat5 pathway to inhibit apoptosis and mediate the proliferation of definitive erythroid progenitors. Similar responses to Epo have also been reported in neurons, cardiomyocytes, and several cancer cell types. However, little is known regarding the function of Epo/EpoR in the first erythroid cells of the developing embryo, the yolk sac-derived, primitive erythroblasts that emerge from a transient wave of progenitors and mature as a synchronous cohort in the fetal vasculature. We have previously determined that EpoR transcripts are present in yolk-sac blood islands beginning at E7.5 (McGann et al., Exp Hem, 1997). Here, we examine the function of Epo/EpoR in embryonic erythropoiesis. Using a colony-forming assay, we found normal levels of primitive erythroid progenitor activity in E8.5 Epor-null embryos. However, these colonies were composed of markedly fewer cells, suggesting a defect in the erythroid precursor maturation. Consistent with these in vitro results, we found that E10.5 Epor-null embryos contain 60% fewer primitive erythroblasts compared to wild-type littermates. Cell cycle analysis revealed a block at the transition from G1- to S-phase with a greater than 2-fold increase in the proportion of erythroblasts in G1-phase in Epor-null versus wild-type embryos. Furthermore, utilizing multi-spectral imaging flow cytometry, we found that E10.5 and E11.5 Epor-null primitive erythroblasts exhibit decreased cell size, nuclear size, and RNA content. Transcriptional analysis revealed a higher εy:βH1 expression ratio in Epor-null erythroblasts consistent with a more rapid maturational globin switch. Most strikingly, we detected a 10-fold reduction in CD71 (transferrin receptor) cell surface expression, which led us to investigate its transcript levels along with other known Stat5-target genes. CD71, Myc, and Bcl-xl transcript levels were all reduced significantly in Epor-null compared to wild-type erythroblasts. Furthermore, we found robust phosphorylation of Stat5 in primitive erythroid precursors that increased upon exposure to Epo. Taken together, our findings indicate that Epo/EpoR signaling is not required for the specification or emergence of primitive erythroid progenitors. However, the subsequent proliferative maturation of primitive erythroid precursors is highly dependent on Epo/EpoR signaling and modulation of Stat5-target genes. The marked reduction of primitive erythroid precursors in Epor-null embryos is associated with cell cycle defects. Furthermore, Epor-null primitive erythroblasts exhibit a phenotype of premature maturation, characterized by decreased cell size, nuclear size, RNA content, and altered globin switching. Finally, the drastic reduction of CD71 expression supports the concept that Epo regulates iron metabolism through Stat5-mediated signaling. We conclude that erythropoietin is a critical regulator of primitive erythropoiesis in the mammalian embryo. However, unlike definitive erythropoiesis, Epo/EpoR primarily regulates the primitive lineage at the precursor rather than the progenitor stage of maturation. Disclosures: No relevant conflicts of interest to declare.

scholarly journals EFFECT OF METABOLIC INHIBITORS ON NUCLEAR PORE FORMATION DURING THE HELA S3 CELL CYCLE

1973 ◽  
Vol 59 (3) ◽  
pp. 669-676 ◽  
Author(s):  
Helmut M. Maul ◽  
Betty Yee Li Hsu ◽  
Thaddeus M. Borun ◽  
Gerd G. Maul
Keyword(s):  
Cell Cycle ◽  
Pore Formation ◽  
Atp Synthesis ◽  
Nuclear Size ◽  
Size Increase ◽  
Metabolic Inhibitors ◽  
Nuclear Pore ◽  
Nuclear Surface ◽  
Etching Technique ◽  
Hela S3

The effect of various antimetabolites on nuclear pore formation was studied in synchronized HeLa S3 cells. The nuclear size was determined by light microscopy and the pore number per unit area of nuclear surface by the freeze-etching technique and electron microscopy. It was found that the inhibition of DNA replication or ribosomal RNA synthesis has no effect on nuclear size increase or pore formation. However, the inhibition of ATP synthesis effectively stops nuclear pore formation. Cycloheximide blocks nuclear pore formation at the same time during G1 phase of the cell cycle when nuclear size increase is blocked by high concentrations of actinomycin D. This suggests that certain proteins or other factors leading to pore formation and nuclear size increase are transcribed and synthesized at about 3–4 h after mitosis, i.e., about 1–2 h before S phase begins.

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.

Maytansine-Induced Mitotic Arrest in Human Lymphoblasts

1977 ◽  
Vol 35 ◽  
pp. 460-461
Author(s):  
Tai-Te Chao ◽  
John Sullivan ◽  
Awtar Krishan
Keyword(s):  
Electron Microscopy ◽  
Cell Cycle ◽  
Transmission Electron Microscopy ◽  
Tubulin Polymerization ◽  
Vinca Alkaloids ◽  
Antimitotic Activity ◽  
Transmission Electron ◽  
Flow Microfluorometry ◽  
Brain Tubulin

Maytansine, a novel ansa macrolide (1), has potent anti-tumor and antimitotic activity (2, 3). It blocks cell cycle traverse in mitosis with resultant accumulation of metaphase cells (4). Inhibition of brain tubulin polymerization in vitro by maytansine has also been reported (3). The C-mitotic effect of this drug is similar to that of the well known Vinca- alkaloids, vinblastine and vincristine. This study was carried out to examine the effects of maytansine on the cell cycle traverse and the fine struc- I ture of human lymphoblasts.Log-phase cultures of CCRF-CEM human lymphoblasts were exposed to maytansine concentrations from 10-6 M to 10-10 M for 18 hrs. Aliquots of cells were removed for cell cycle analysis by flow microfluorometry (FMF) (5) and also processed for transmission electron microscopy (TEM). FMF analysis of cells treated with 10-8 M maytansine showed a reduction in the number of G1 cells and a corresponding build-up of cells with G2/M DNA content.

Fibronexus-Like Adhesion Sites are Present at the Invasive Zones of Human Epidermoid Carcinomas

1982 ◽  
Vol 40 ◽  
pp. 106-109
Author(s):  
Irwin I. Singer
Keyword(s):  
Cell Cycle ◽  
Serum Concentration ◽  
Substrate Binding ◽  
High Serum ◽  
Adhesion Sites ◽  
Substrate Adhesion ◽  
Focal Contacts ◽  
Adhesion Complex ◽  
Low Serum

Our previous results indicate that two types of fibronectin-cytoskeletal associations may be formed at the fibroblast surface: dorsal matrixbinding fibronexuses generated in high serum (5% FBS) cultures, and ventral substrate-adhering units formed in low serum (0.3% FBS) cultures. The substrate-adhering fibronexus consists of at least vinculin (VN) and actin in its cytoplasmic leg, and fibronectin (FN) as one of its major extracellular components. This substrate-adhesion complex is localized in focal contacts, the sites of closest substratum approach visualized with interference reflection microscopy, which appear to be the major points of cell-tosubstrate adhesion. In fibroblasts, the latter substrate-binding complex is characteristic of cultures that are arrested at the G1 phase of the cell cycle due to the low serum concentration in their medium. These arrested fibroblasts are very well spread, flattened, and immobile.

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