scholarly journals Characterization of two populations of statin and the relationship of their syntheses to the state of cell proliferation.

1990 ◽  
Vol 110 (2) ◽  
pp. 255-261 ◽  
Author(s):  
G Ching ◽  
E Wang
Keyword(s):  
Nuclear Envelope ◽  
Present Report ◽  
Human Fibroblasts ◽  
Quiescent State ◽  
Serum Stimulation ◽  
Cellular Expression ◽  
G0 Phase ◽  
Triton X ◽  
Relationship Of ◽  
Two Populations

Statin has previously been identified to be a 57-kD protein present in the nuclei of quiescent and senescent human fibroblasts, but not in their replicating counterparts (Wang, E. 1985. J. Cell Biol. 100: 545-551). In the present report we demonstrate by immunoprecipitation analysis of fractionated cellular extracts the existence of two populations of statin. The Triton X-100-soluble statin is found in replicating sparse cultures as well as in quiescent confluent cultures and quiescent serum-starved cultures of young human fibroblasts, but the Triton X-100-insoluble, nuclear envelope-localized statin is present only in the quiescent cultures. Two-dimensional gel analysis of the immunoprecipitated cellular fractions reveals that both populations of statin have an isoelectric point of 5.3. Pulse-chase experiments show that statin is synthesized as a 57-kD polypeptide and is not processed from a precursor of different molecular mass. Experiments on serum stimulation of quiescent cells show that synthesis of the Triton X-100-insoluble statin decreases rapidly during the transition from the G0 to S phase, and that this decrease is accompanied by a slower reduction in synthesis of the Triton X-100-soluble statin. These results suggest that the cellular expression of the two populations of statin may be associated with the mechanisms controlling the transition between the growing state and the quiescent state and confirm the previous finding that the Triton X-100-insoluble, nuclear envelope-localized statin could be used as a marker for cells arrested at the G0 phase of the cell cycle.

Intra-Task Reliability and Specificity of Individual Consistency

1970 ◽  
Vol 30 (2) ◽  
pp. 583-587 ◽  
Author(s):  
Albert V. Carron
Keyword(s):  
Motor Response ◽  
Present Report ◽  
Motor Task ◽  
Response Component ◽  
Linear Movement ◽  
The Mean ◽  
Individual Consistency ◽  
Response Consistency ◽  
Relationship Of ◽  
The Relationship

The present report is based on reanalysis of data of Marisi (1969) in order to examine the relationship of consistency of motor response among the component responses of a single motor task. 120 high school Ss were tested on a special task, the rho. A single trial on this motor task can be logically separated into three component motor responses: reaction time, a short circular movement, and a short linear movement. The results indicated that consistency of motor response was moderately reliable within the response components but tended to be response-component specific. Further, both the reliability and specificity of motor-response consistency were independent of the size of the mean performance scores.

scholarly journals A Structure−Permeability Relationship of Ultrathin Nanoporous Silicon Membrane:  A Comparison with the Nuclear Envelope

2008 ◽  
Vol 130 (13) ◽  
pp. 4230-4231 ◽  
Author(s):  
Eunkyoung Kim ◽  
Hui Xiong ◽  
Christopher C. Striemer ◽  
David Z. Fang ◽  
Philippe M. Fauchet ◽  
...  
Keyword(s):  
Nuclear Envelope ◽  
Silicon Membrane ◽  
Nanoporous Silicon ◽  
Relationship Of

An endogenous carbohydrate-binding protein of baby hamster kidney (BHK21 C13) cells. Temporal changes in cellular expression in the developing kidney

1990 ◽  
Vol 97 (1) ◽  
pp. 139-148
Author(s):  
L. Foddy ◽  
S.C. Stamatoglou ◽  
R.C. Hughes
Keyword(s):  
Cell Line ◽  
Kidney Development ◽  
Immunofluorescent Staining ◽  
Carbohydrate Binding ◽  
Baby Hamster Kidney ◽  
Cellular Expression ◽  
Established Cell ◽  
Developing Kidney ◽  
Triton X ◽  
Newborn Hamster

Asialofetuin (ASF) coupled to Sepharose has been used to isolate a Mr 30,000 protein from Triton X-100 extracts of the baby hamster kidney cell line BHK21 C13. Binding to ASF-Sepharose was specific for terminal beta-galactosyl residues. The lectin requires detergent for optimal solubilization and binding is independent of Ca2+ or reducing reagents. The lectin was labelled in a lactoperoxidase-catalysed iodination of intact BHK21 C13 cells, suggesting that it is associated with the cell surface. Antibodies to the lectin identify in Western blotting cross-reactive components in established cell lines of kidney (MDCK, NRK) and non-kidney (L, CHO, 3T3) origin. In young adult hamsters, the lectin is expressed in colon and duodenum and in lesser amounts in ileum, stomach, lung, liver and testes but is absent in kidney. The lectin is expressed in late embryonic and newborn hamster kidney but expression declines during 14 days after birth. Immunofluorescent staining of cryostat sections of newborn hamster kidney and intestine show that the lectin is expressed at apical epithelial surfaces. The presence of the lectin at the luminal surface of kidney tubules suggests a tubular origin for the BHK21 C13 cell line. Possible functions of the Mr 30,000 lectin in kidney development are discussed.

scholarly journals Molecular cloning of a novel mitogen-inducible nuclear protein with a Ran GTPase-activating domain that affects cell cycle progression.

1995 ◽  
Vol 15 (1) ◽  
pp. 552-560 ◽  
Author(s):  
M Hattori ◽  
N Tsukamoto ◽  
M S Nur-e-Kamal ◽  
B Rubinfeld ◽  
K Iwai ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Cell Cycle Progression ◽  
Nuclear Protein ◽  
Interleukin 2 ◽  
Quiescent State ◽  
Cycle Progression ◽  
Ran Gtpase ◽  
G0 Phase ◽  
Nih 3T3

We have cloned a novel cDNA (Spa-1) which is little expressed in the quiescent state but induced in the interleukin 2-stimulated cycling state of an interleukin 2-responsive murine lymphoid cell line by differential hybridization. Spa-1 mRNA (3.5 kb) was induced in normal lymphocytes following various types of mitogenic stimulation. In normal organs it is preferentially expressed in both fetal and adult lymphohematopoietic tissues. A Spa-1-encoded protein of 68 kDa is localized mostly in the nucleus. Its N-terminal domain is highly homologous to a human Rap1 GTPase-activating protein (GAP), and a fusion protein of this domain (SpanN) indeed exhibited GAP activity for Rap1/Rsr1 but not for Ras or Rho in vitro. Unlike the human Rap1 GAP, however, SpanN also exhibited GAP activity for Ran, so far the only known Ras-related GTPase in the nucleus. In the presence of serum, stable Spa-1 cDNA transfectants of NIH 3T3 cells (NIH/Spa-1) hardly overexpressed Spa-1 (p68), and they grew as normally as did the parental cells. When NIH/Spa-1 cells were serum starved to be arrested in the G1/G0 phase of the cell cycle, however, they, unlike the control cells, exhibited progressive Spa-1 p68 accumulation, and following the addition of serum they showed cell death resembling mitotic catastrophes of the S phase during cell cycle progression. The results indicate that the novel nuclear protein Spa-1, with a potentially active Ran GAP domain, severely hampers the mitogen-induced cell cycle progression when abnormally and/or prematurely expressed. Functions of the Spa-1 protein and its regulation are discussed in the context of its possible interaction with the Ran/RCC-1 system, which is involved in the coordinated nuclear functions, including cell division.

scholarly journals Incidence of the Common Forms of Human Leukemia

Blood ◽  
1956 ◽  
Vol 11 (10) ◽  
pp. 871-881 ◽  
Author(s):  
BRIAN MACMAHON ◽  
DUNCAN CLARK
Keyword(s):  
White Cell Count ◽  
Cell Types ◽  
Human Leukemia ◽  
Death Certificates ◽  
Hospital Records ◽  
White Males ◽  
Lymphatic Leukemia ◽  
Younger Age ◽  
Relationship Of ◽  
Two Populations

Abstract From hospital records and from death certificates, an attempt was made to assemble data on all residents of the Borough of Brooklyn diagnosed as having leukemia in the period 1943-52. A total of 1792 abstracts of hospital records and 1830 death certificates gave information on 1709 patients. The mean Brooklyn population over the same period is used to express incidences of the various forms of leukemia in relation to color, sex and age. The incidence of leukemia in white males and females was 71.3 and 57.7 per million per annum respectively. Corresponding rates for Negroes were 46.5 and 30.6. The white-Negro difference was decreased but not eliminated by standardization to allow for differences in the age distributions of the two populations. Sex ratios were lower for the acute forms of the disease than for the chronic forms, and, in both acute and chronic forms, for myeloid than for lymphatic cell types. No relationship of sex ratio with age at diagnosis or initial white cell count was found. Each pathologic variety of leukemia has its own distinct age incidence curve. The lymphatic forms appear to be more sharply associated with the extremes of life than do the myeloid varieties. That is, acute lymphatic leukemia appears at a younger age than does acute myeloid leukemia and the chronic lymphatic form appears at an older average age than the chronic myeloid variety.

scholarly journals Distribution of ABL and BCR Genes in Cell Nuclei of Normal and Irradiated Lymphocytes

Blood ◽  
1997 ◽  
Vol 89 (12) ◽  
pp. 4537-4545 ◽  
Author(s):  
S. Kozubek ◽  
E. Lukášová ◽  
L. Rýznar ◽  
M. Kozubek ◽  
A. Lišková ◽  
...  
Keyword(s):  
Chromatin Structure ◽  
Human Fibroblasts ◽  
Physical Distance ◽  
Gene Arrangement ◽  
Cell Nuclei ◽  
Interphase Nuclei ◽  
Γ Radiation ◽  
Shortest Distance ◽  
G0 Phase

Abstract Using dual-color fluorescence in situ hybridization (FISH) combined with two-dimensional (2D) image analysis, the locations of ABL and BCR genes in cell nuclei were studied. The center of nucleus-to-gene and mutual distances of ABL and BCR genes in interphase nuclei of nonstimulated and stimulated lymphocytes as well as in lymphocytes stimulated after irradiation were determined. We found that, after stimulation, the ABL and BCR genes move towards the membrane, their mutual distances increase, and the shortest distance between heterologous ABL and BCR genes increases. The distribution of the shortest distances between ABL and BCR genes in the G0 phase of lymphocytes corresponds to the theoretical distribution calculated by the Monte-Carlo simulation. Interestingly, the shortest ABL-BCR distances in G1 and S(G2 ) nuclei are greater in experiment as compared with theory. This result suggests the existence of a certain regularity in the gene arrangement in the G1 and S(G2 ) nuclei that keeps ABL and BCR genes at longer than random distances. On the other hand, in about 2% to 8% of lymphocytes, the ABL and BCR genes are very close to each other (the distance is less than ∼0.2 to 0.3 μm). For comparison, we studied another pair of genes, c-MYC and IgH, that are critical for the induction of t(8; 14) translocation that occurs in the Burkitt's lymphoma. We found that in about 8% of lymphocytes, c-MYC and IgH are very close to each other. Similar results were obtained for human fibroblasts. γ-Radiation leads to substantial changes in the chromatin structure of stimulated lymphocytes: ABL and BCR genes are shifted to the nuclear center, and mutual ABL-BCR distances become much shorter in the G1 and S(G2 ) nuclei. Therefore, we hypothesize that the changes of chromatin structure in the irradiated lymphocytes might increase the probability of a translocation during G1 and S(G2 ) stages of the cell cycle. The fact that the genes involved in the t(8; 14) translocation are also located close together in a certain fraction of cells substantiates the hypothesis that physical distance plays an important role in the processes leading to the translocations that are responsible for oncogenic transformation of cells.

scholarly journals Localization of oxidized nocotinamide–adenine dinucleotide glycohydrolase in the mouse liver nuclear envelope

1979 ◽  
Vol 178 (2) ◽  
pp. 467-473 ◽  
Author(s):  
P Tamulevicius ◽  
C Streffer ◽  
O Roscic ◽  
E Hubert
Keyword(s):  
Electron Microscopy ◽  
Enzyme Activity ◽  
Nuclear Envelope ◽  
Mouse Liver ◽  
Residual Activity ◽  
Latent Form ◽  
Nad Glycohydrolase ◽  
Nuclear Membranes ◽  
Deoxyribonuclease I ◽  
Triton X

NAD+ glycohydrolase activity located in the nuclear envelope was maximally solubilized by treatment with 0.1–0.2% Triton X-100. The residual activity largely represents the chromatin-associated NAD+ glycohydrolase. Under these conditions the phospholipids were extensively solubilized (over 90%) while leaving the nuclei physically stable, although the nuclear membranes were removed, as shown by electron microscopy. After Triton X-100 treatment, deoxyribonuclease I did not significantly affect the residual NAD+ glycohydrolase activity, although the DNA was completely broken down. This enzyme activity can be released from the nuclear pellet by incubation with phospholipase C. For comparative studies, the glucose 6-phosphatase activity, known to be present in the nuclear envelope, was investigated. Treatment with 0.01% Triton X-100 released 10–20% of the phospholipids, but without solubilizing either glucose 6-phosphatase or NAD+ glycohydrolase. Higher Triton X-100 concentrations (0.1–1.0%) inhibited glucose 6-phosphatase, but not NAD+ glycohydrolase activity. NAD+ glycohydrolase is apparently present in a latent form in the nuclear envelope. Glucose 6-phosphatase, However, shows no such latency.

Constitutive expression of the E2F1 transcription factor in fibroblasts alters G0 and S phase transit following serum stimulation

1996 ◽  
Vol 74 (1) ◽  
pp. 21-28 ◽  
Author(s):  
Thomas J. Logan ◽  
Kelly L. Jordan ◽  
David J. Hall
Keyword(s):  
Cell Cycle ◽  
Transcription Factor ◽  
Cell Lines ◽  
Constitutive Expression ◽  
S Phase ◽  
G1 Phase ◽  
Serum Starvation ◽  
Serum Stimulation ◽  
G0 Phase ◽  
E2f1 Transcription Factor

The E2F1 transcription factor was constitutively expressed in NIH3T3 fibroblasts to determine its effect on the cell cycle. These E2F1 cell lines were not tightly synchronized in G0 phase of the cell cycle following serum starvation, as are normal fibroblasts. Instead, the cells are spread throughout G0 and G1 phase with a portion of the population initiating DNA synthesis. Upon serum stimulation, the remaining cells in G0/G1 begin to enter S phase immediately but with a reduced rate. Constitutive expression of E2F1 appears to primarily affect the G0 phase, since transit of proliferating E2F1 cell lines through G1 phase is the same as control cells. Consistent with a shortened G0 phase, the E2F1 cell lines have a significantly reduced cellular volume. Additionally, the first S phase after serum stimulation, but not subsequent S phases, is nearly doubled in the E2F1 cell lines compared with control cells. Cell lines expressing a deletion mutant of E2F1 (termed E2F1d87), known to significantly affect cell shape, have cell cycle and volume characteristics similar to the E2F1 expressing cells. However, all S phase durations are considerably lengthened and the cells demonstrate delayed growth after plating.Key words: cell cycle, E2F1 transcription factor, G0/G1 phase.

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