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Literaturverzeichnis. Acta Otolaryngol 2009. [DOI: 10.3109/00016487009121245] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Boisnard-Lorig C, Colon-Carmona A, Bauch M, Hodge S, Doerner P, Bancharel E, Dumas C, Haseloff J, Berger F. Dynamic analyses of the expression of the HISTONE::YFP fusion protein in arabidopsis show that syncytial endosperm is divided in mitotic domains. THE PLANT CELL 2001; 13:495-509. [PMID: 11251092 PMCID: PMC135513 DOI: 10.1105/tpc.13.3.495] [Citation(s) in RCA: 283] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2000] [Accepted: 01/05/2001] [Indexed: 05/17/2023]
Abstract
During early seed development, nuclear divisions in the endosperm are not followed by cell division, leading to the development of a syncytium. The simple organization of the Arabidopsis endosperm provides a model in which to study the regulation of the cell cycle in relation to development. To monitor nuclear divisions, we constructed a HISTONE 2B::YELLOW FLUORESCENT PROTEIN gene fusion (H2B::YFP). To validate its use as a vital marker for chromatin in plants, H2B::YFP was expressed constitutively in Arabidopsis. This enabled the observation of mitoses in living root meristems. H2B::YFP was expressed specifically in Arabidopsis syncytial endosperm by using GAL4 transactivation. Monitoring mitotic activity in living syncytial endosperm showed that the syncytium was organized into three domains in which nuclei divide simultaneously with a specific time course. Each mitotic domain has a distinct spatiotemporal pattern of mitotic CYCLIN B1;1 accumulation. The polar spatial organization of the three mitotic domains suggests interactions between developmental mechanisms and the regulation of the cell cycle.
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Affiliation(s)
- C Boisnard-Lorig
- Unité Mixte de Recherche 5667, Centre National de la Recherche Scientifique, Institut National de la Recherche Agronomique, Ecole Nationale Supérieure de Lyon, Université Lyon I, 46 Allée d'Italie, 69364 Lyon Cedex 07, France
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Boisnard-Lorig C, Colon-Carmona A, Bauch M, Hodge S, Doerner P, Bancharel E, Dumas C, Haseloff J, Berger F. Dynamic analyses of the expression of the HISTONE::YFP fusion protein in arabidopsis show that syncytial endosperm is divided in mitotic domains. THE PLANT CELL 2001. [PMID: 11251092 DOI: 10.2307/3871402] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
During early seed development, nuclear divisions in the endosperm are not followed by cell division, leading to the development of a syncytium. The simple organization of the Arabidopsis endosperm provides a model in which to study the regulation of the cell cycle in relation to development. To monitor nuclear divisions, we constructed a HISTONE 2B::YELLOW FLUORESCENT PROTEIN gene fusion (H2B::YFP). To validate its use as a vital marker for chromatin in plants, H2B::YFP was expressed constitutively in Arabidopsis. This enabled the observation of mitoses in living root meristems. H2B::YFP was expressed specifically in Arabidopsis syncytial endosperm by using GAL4 transactivation. Monitoring mitotic activity in living syncytial endosperm showed that the syncytium was organized into three domains in which nuclei divide simultaneously with a specific time course. Each mitotic domain has a distinct spatiotemporal pattern of mitotic CYCLIN B1;1 accumulation. The polar spatial organization of the three mitotic domains suggests interactions between developmental mechanisms and the regulation of the cell cycle.
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Affiliation(s)
- C Boisnard-Lorig
- Unité Mixte de Recherche 5667, Centre National de la Recherche Scientifique, Institut National de la Recherche Agronomique, Ecole Nationale Supérieure de Lyon, Université Lyon I, 46 Allée d'Italie, 69364 Lyon Cedex 07, France
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Belmont AS, Bruce K. Visualization of G1 chromosomes: a folded, twisted, supercoiled chromonema model of interphase chromatid structure. J Cell Biol 1994; 127:287-302. [PMID: 7929576 PMCID: PMC2120203 DOI: 10.1083/jcb.127.2.287] [Citation(s) in RCA: 226] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
We have used light microscopy and serial thin-section electron microscopy to visualize intermediates of chromosome decondensation during G1 progression in synchronized CHO cells. In early G1, tightly coiled 100-130-nm "chromonema" fibers are visualized within partially decondensed chromatin masses. Progression from early to middle G1 is accompanied by a progressive uncoiling and straightening of these chromonema fibers. Further decondensation in later G1 and early S phase results in predominantly 60-80-nm chromonema fibers that can be traced up to 2-3 microns in length as discrete fibers. Abrupt transitions in diameter from 100-130 to 60-80 nm along individual fibers are suggestive of coiling of the 60-80-nm chromonema fibers to form the thicker 100-130-nm chromonema fiber. Local unfolding of these chromonema fibers, corresponding to DNA regions tens to hundreds of kilobases in length, reveal more loosely folded and extended 30-nm chromatin fibers. Kinks and supercoils appear as prominent features at all observed levels of folding. These results are inconsistent with prevailing models of chromosome structure and, instead, suggest a folded chromonema model of chromosome structure.
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Affiliation(s)
- A S Belmont
- Department of Cell and Structural Biology, University of Illinois, Champaign-Urbana 61801
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Kantor GJ, Hull DR. An effect of ultraviolet light on RNA and protein synthesis in nondividing human diploid fibroblasts. Biophys J 1979; 27:359-70. [PMID: 95567 PMCID: PMC1328594 DOI: 10.1016/s0006-3495(79)85223-6] [Citation(s) in RCA: 38] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Nondividing human diploid fibroblasts maintained in medium containing 0.5% calf serum do not survive when exposed to low doses of UV (254 nm). The extent of killing is dose and strain dependent. DNA excision repair-proficient cells are more resistant than excision repair-deficient cells. Results of measurements of the effect of UV on RNA and protein synthesis in repair-proficient and -deficient (XP12BE) cells are reported. UV causes an immediate and equal depression of the RNA synthesis rate in both kinds of cells. A recovery to control rates was observed only at low (5 J/m2) doses in repair-deficient cells and at higher doses (20 J/m2) in repair-proficient cells. No recovery was observed at doses that cause substantial reductions in survival (greater than 5 J/m2 for XP12BE; greater than 40 J/m2 for repair-proficient populations). No initial effect on rate of protein synthesis was detected at doses less than 20 J/m2. However, in XP12BE populations, a decreased rate first evident at 15-30 h post-UV and before any cell degeneration and loss was observed for doses as low at 7 J/m2. This delayed effect was not observed in repair-proficient populations. The results are consistent with the hypothesis that the lethal action of UV in nondividing cells is one on DNA that leads to an inhibition of required protein synthesis by preventing RNA transcription.
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Melero JA, Fincham V. Enhancement of the synthesis of specific cellular polypeptides in a temperature-sensitive Chinese hamster cell line (K12) defective for entry into S phase. J Cell Physiol 1978; 95:295-306. [PMID: 649666 DOI: 10.1002/jcp.1040950307] [Citation(s) in RCA: 29] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Temperature-sensitive Chinese hamster cells (K12) have been shown to be defective for the initiation of new rounds of DNA replication when incubated at the restrictive temperature (40.5 degrees). By temperature shift experiments with synchronous cultures, we have marked out the step at which the mutation is expressed as the four hours preceding the initiation of DNA synthesis. The block imposed by the mutation has been shown to be irreversible. In order to approach the biochemical characterization of the temperature-sensitive function in K12 cells, we have analyzed the cellular proteins synthesized under permissive (35 degrees) and restrictive temperatures. The synthesis of three polypeptides is markedly enhanced when K12 cells are incubated at 40.5 degrees. One of them (band B) has turned out to be a useful biochemical marker of the expression of K12 mutation since its synthesis is not affected in other ts-mutants or in hybrids in which K12 mutation is complemented. In addition, the alteration in band B synthesis is irreversible and occurs during the same stage of the cell cycle at which the mutated function is expressed.
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Cone CD, Tongier M, Cone CM. DNA content of daughter nuclei from ouabain-induced nuclear divisions in central nervous system neurons. Exp Neurol 1977; 57:396-408. [PMID: 908380 DOI: 10.1016/0014-4886(77)90075-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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Swartzendruber DE. Microfluorometric analysis of cellular DNA following incorporation of bromodeoxyuridine. J Cell Physiol 1977; 90:445-53. [PMID: 67119 DOI: 10.1002/jcp.1040900308] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Bromodeoxyuridine (BrdU) incorporation into cellular DNA has a differential effect on the cell-associated fluorescence of several DNA-specific dyes. After cells were treated with BrdU, flow microfluorometry was used to study the relative increase or decrease influorescence of stained cells. Bromodeoxyuridine incorporation into CHO cells increased the fluorescence of mithramycin-, olivomycin-, or chromomycin-stained cells, decreased that of propidium iodide-stained cells, and had little, if any, effect on the fluorescence of acriflavine Feulgen-stained cells. Changes in relative fluorescence of cell associated dyes are due to changes in the amounts of dye bound to cells with BrdU-substituted DNA. Colorimetric and absorbance measurement of DNA content showed that BrdU does not alter the diploid DNA content of CHO cells; however, BrdU induces perturbations in the distribution of cells about the cell cycle which cause an increase in average DNA content.
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Robinson JH, Smith JA, Totty NF, Riddle PN. Transition probability and the hormonal and density-dependent regulation of cell proliferation. Nature 1976; 262:298-300. [PMID: 958375 DOI: 10.1038/262298a0] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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Noland BJ, Walters RA, Tobey RA, Hardin JM, Shepherd GR. Effects of ionizing radiation upon intracellular levels of soluble microtubule protein in cultured mammalian cells. Exp Cell Res 1974; 85:234-8. [PMID: 4857153 DOI: 10.1016/0014-4827(74)90122-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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Walters RA, Tobey RA, Ratliff RL. Cell-cycle-dependent variations of deoxyribonucleoside triphosphate pools in Chinese hamster cells. BIOCHIMICA ET BIOPHYSICA ACTA 1973; 319:336-47. [PMID: 4795783 DOI: 10.1016/0005-2787(73)90173-1] [Citation(s) in RCA: 122] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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Tobey RA. Production and characterization of mammalian cells reversibly arrested in G1 by growth in isoleucine-deficient medium. Methods Cell Biol 1973; 6:67-112. [PMID: 4585084 DOI: 10.1016/s0091-679x(08)60048-5] [Citation(s) in RCA: 59] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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Gurley LR, Walters RA, Tobey RA. The metabolism of histone fractions. VI. Differences in the phosphorylation of histone fractions during the cell cycle. Arch Biochem Biophys 1973; 154:212-8. [PMID: 4734724 DOI: 10.1016/0003-9861(73)90051-9] [Citation(s) in RCA: 58] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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Gurley LR, Walters RA. The metabolism of histone fractions. V. The relationship between histone and DNA synthesis after x-irradiation. Arch Biochem Biophys 1972; 153:304-11. [PMID: 4675448 DOI: 10.1016/0003-9861(72)90449-3] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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OHTSUKI H, AMANO M. RNA SYNTHESIS IN THE DIFFERENT PHASES OF CELL CYCLE OF CHICK EMBRYO CELLS. Dev Growth Differ 1972. [DOI: 10.1111/j.1440-169x.1972.00197.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Tobey RA. Arrest of Chinese hamster cells in G 2 following treatment with the anti-tumor drug bleomycin. J Cell Physiol 1972; 79:259-66. [PMID: 4112708 DOI: 10.1002/jcp.1040790210] [Citation(s) in RCA: 46] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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Gurley LR, Walters RA, Tobey RA. The metabolism of histone fractions. IV. Synthesis of histones during the G1-phase of the mammalian life cycle. Arch Biochem Biophys 1972; 148:633-41. [PMID: 5063077 DOI: 10.1016/0003-9861(72)90182-8] [Citation(s) in RCA: 63] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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Emerson CP. Regulation of the synthesis and the stability of ribosomal RNA during contact inhibition of growth. NATURE: NEW BIOLOGY 1971; 232:101-6. [PMID: 5284943 DOI: 10.1038/newbio232101a0] [Citation(s) in RCA: 120] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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Melera PW. Nucleic Acid Metabolism in Germinating Onion: I. Changes in Root Tip Nucleic Acid during Germination. PLANT PHYSIOLOGY 1971; 48:73-81. [PMID: 16657739 PMCID: PMC396804 DOI: 10.1104/pp.48.1.73] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Nucleic acid synthesis in the G(1) cell population of the 1-millimeter apex of the Allium cepa embryo was studied during the initial 73 hours of germination. Quantitative data indicate that the total amount of RNA per cell began to increase after 18 hours of germination while the initial DNA per cell increase did not occur until some 20 hours later. Polyacrylamide gel electrophoresis patterns of (3)H-uridine-labeled total nucleic acid samples indicated that synthesis of all detectable RNA fractions present in the pre-emergent 1-millimeter apex (i.e., cytoplasmic and "chloroplast-like" RNA) began at approximately the same time (18 hours). Synthesis of the various cytoplasmic RNA fractions continued throughout the germination period. Data indicating synthesis of the "chloroplast-like" RNA were obtained only for the initial 36 hours of germination. Specific radioactivity of (3)H-uridine-labeled total nucleic acid increased during the first 41.5 hours of germination but then decreased while the accumulation of RNA per cell continued to increase throughout the 73-hour period. In addition, a method is described which reduced the bacterial contamination of Allium seed to a level not detectable by incorporation of radioactive precursors into bacterial ribosomal RNA.
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Affiliation(s)
- P W Melera
- Botany Department, University of Georgia, Athens, Georgia 30601
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Blomquist CH, Gregg CT, Tobey RA. Enzyme and coenzyme levels, oxygen uptake and lactate production in synchronized cultures of Chinese hamster cells. Exp Cell Res 1971; 66:75-80. [PMID: 4397277 DOI: 10.1016/s0014-4827(71)80013-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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Johnson RT, Rao PN. Nucleo-cytoplasmic interactions in the acheivement of nuclear synchrony in DNA synthesis and mitosis in multinucleate cells. Biol Rev Camb Philos Soc 1971; 46:97-155. [PMID: 4399534 DOI: 10.1111/j.1469-185x.1971.tb01180.x] [Citation(s) in RCA: 95] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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Maden B. The structure and formation of ribosomes in animal cells. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 1971. [DOI: 10.1016/0079-6107(71)90007-1] [Citation(s) in RCA: 105] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Burdon RH. Ribonucleic acid maturation in animal cells. PROGRESS IN NUCLEIC ACID RESEARCH AND MOLECULAR BIOLOGY 1971; 11:33-79. [PMID: 5145747 DOI: 10.1016/s0079-6603(08)60325-6] [Citation(s) in RCA: 81] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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Abstract
The capacity of cells to produce interferon has been found to depend on the phase in the cell cycle at which virus infection took place. Monolayer cultures of L cells were synchronized by the double thymidine-block method. Such synchronously growing cultures were used to study the ability of cells to produce interferon when they were infected with ultraviolet-inactivated Newcastle disease virus (UV-NDV) at different phases of the cell cycle. In all instances, interferon was detected early and reached a maximum at about 16 hr after infection. However, the levels of interferon found in medium of cultures infected at early post-deoxyribonucleic acid (DNA) synthetic (G2) and to some extent at late G2 phases of the cell cycle were comparatively lower than those found in cultures infected at the early DNA synthetic (S) phase. There appeared also in these infected growing cultures a transient period when interferon production was apparently delayed. This period corresponded interestingly with the time of mitotic burst. Infection of thymidine- or 1-beta-d-arabino-furanosylcytosine-inhibited cultures with UV-NDV also led to similar interferon response as that observed in growing cultures infected at early S. However, no transient delay of interferon production was demonstrated in these cultures.
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Tobey RA, Ley KD. Regulation of initiation of DNA synthesis in Chinese hamster cells. I. Production of stable, reversible G1-arrested populations in suspension culture. J Cell Biol 1970; 46:151-7. [PMID: 5460461 PMCID: PMC2108064 DOI: 10.1083/jcb.46.1.151] [Citation(s) in RCA: 120] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Suspension cultures of Chinese hamster cells (line CHO) were grown to stationary phase (approximately 8-9 x 10(5) cells/ml) in F-10 medium. Cells remained viable (95%) for at least 80 hr in stationary phase, and essentially all of the cells were in G(1) Upon resuspension or dilution with fresh medium, the cells were induced to resume traverse of the life cycle in in synchrony, and the patterns of DNA synthesis and division were similar to those observed in cultures prepared by mitotic selection. Immediately after dilution, the rates of synthesis of RNA and protein increased threefold. This system provides a simple technique for production of large quantities of highly synchronized cells and may ultimately provide information on the biochemical mechanisms regulating cell-cycle traverse.
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Anderson EC, Petersen DF, Tobey RA. Density invariance of cultured Chinese hamster cells with stage of the mitotic cycle. Biophys J 1970; 10:630-45. [PMID: 5465290 PMCID: PMC1367787 DOI: 10.1016/s0006-3495(70)86325-1] [Citation(s) in RCA: 60] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Isopycnic banding of Chinese hamster line CHO cells in Ficoll gradients shows that a population in balanced, exponential growth is very homogeneous with respect to density, the coefficient of variation of the density distribution spectrum being less than 5% of the mean reduced density (i.e. density minus one). Similar measurements on synchronized cultures indicate that reduced density varies by less than 2% around the life cycle. The mean density of CHO cells in F-10 growth medium is calculated to be 1.051 after correction for osmotic effects of the Ficoll gradient.
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Pagoulatos GN, Darnell JE. A comparison of the heterogeneous nuclear RNA of HeLa cells in different periods of the cell growth cycle. J Cell Biol 1970; 44:476-83. [PMID: 5415232 PMCID: PMC2107977 DOI: 10.1083/jcb.44.3.476] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
HeLa cells synthesize heterogeneous nuclear RNA (HnRNA) in the G(1), S, and G(2) portions of the cell cycle. HnRNA prepared from these various periods was compared by RNA-DNA hybridization experiments. The results indicated that some of the HnRNA molecules were equivalent at all times in the cell cycle, but limitations in the sensitivity of the hydridization reactions, as well as in the spectrum of hybridizing molecules, restrict the conclusions that can be drawn from these comparisons.
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Gurley LR, Hardin JM. The metabolism of histone fractions. 3. Synthesis and turnover of histone f1. Arch Biochem Biophys 1970; 136:392-401. [PMID: 5461615 DOI: 10.1016/0003-9861(70)90210-9] [Citation(s) in RCA: 43] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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Abstract
The interval between mitosis and initiation of DNA synthesis (G(1)) varied over a fourfold range for Chinese hamster ovary cells, an established line. This was not because of size differences. Synchlronous cells of different sizes began DNA synthesis at similar times after mitosis. A novel technique of centrifugation for separating cells according to size is described.
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Kraus H, Doennig G. [Cytophotometric RNA and protein determination in the membranous labyrinth of guinea pigs as a basis for the evaluation of protein metabolism and streptomycin ototoxicity]. ARCHIV FUR KLINISCHE UND EXPERIMENTELLE OHREN- NASEN- UND KEHLKOPFHEILKUNDE 1969; 194:551-7. [PMID: 4190291] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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Cytophotometrische RNA- und Eiweißbestimmungen am häutigen Innenohr des Meerschweinchens als Grundlagen zur Beurteilung des Eiweißstoffwechsels und der Streptomycin-Ototoxicität. Eur Arch Otorhinolaryngol 1969. [DOI: 10.1007/bf02594536] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Klevecz RR. Temporal order in mammalian cells. I. The periodic synthesis of lactate dehydrogenase in the cell cycle. J Cell Biol 1969; 43:207-19. [PMID: 5344146 PMCID: PMC2107853 DOI: 10.1083/jcb.43.2.207] [Citation(s) in RCA: 71] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Chinese hamster cells were synchronized by the Colcemid-selection system. In cells with a division cycle time of 11.5-12 hr, the activity of the enzyme lactate dehydrogenase (LDH) underwent marked oscillations with a 3.5-hr period. Precipitation of labeled LDH enzyme with specific antibody indicated that the enzyme activity changes were the result of intermittent enzyme synthesis and relatively constant degradation. Inhibition of normal DNA replication with 4 mM of thymidine, while reducing the amount of new enzyme synthesized, did not prevent oscillations from occurring. Similarly, actinomycin D (AcD) added at the time of synchronization allowed some new enzyme synthesis to proceed in an oscillatory manner. LDH synthesis went on at nearly normal rates when AcD was added in the middle of S phase. However, addition of cycloheximide to cultures at any time in the cycle caused an immediate drop in levels of activity and in enzyme protein. The half-life of LDH, calculated either from loss of enzyme activity or precipitable radioactivity in cycloheximide-treated cultures, was between 2 and 2.5 hr.
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Feinendegen LE, Zajdela F. Synchrony of restricted gene transcription in mammalian sister cells in culture. VIRCHOWS ARCHIV. B, CELL PATHOLOGY 1969; 3:51-76. [PMID: 4977670 DOI: 10.1007/bf02901926] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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Enger MD, Tobey RA. RNA synthesis in Chinese hamster cells. II. Increase in rate of RNA synthesis during G1. J Cell Biol 1969; 42:308-15. [PMID: 5795885 PMCID: PMC2107561 DOI: 10.1083/jcb.42.1.308] [Citation(s) in RCA: 49] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
Cultures of mitotic Chinese hamster cells, prepared by mechanical selection, were pulse-labeled with methionine-methyl-(14)C or with uridine-(3)H at different stages in the life cycle. The rate of (14)C incorporation into 18S RNA was measured, as was the rate of uridine-(3)H incorporation into total RNA for both monolayer and suspension cultures. The rate of incorporation increased continuously throughout interphase in a fashion inconsistent with a gene-dosage effect upon RNA synthesis.
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Gurley LR, Hardin JM. The metabolism of histone fractions. II. Conservation and turnover of histone fractions in mammalian cells. Arch Biochem Biophys 1969; 130:1-6. [PMID: 5778638 DOI: 10.1016/0003-9861(69)90002-2] [Citation(s) in RCA: 47] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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Gurley LR, Hardin JM. The metabolism of histone fractions. I. Synthesis of histone fractions during the life cycle of mammalian cells. Arch Biochem Biophys 1968; 128:285-92. [PMID: 5748825 DOI: 10.1016/0003-9861(68)90034-9] [Citation(s) in RCA: 95] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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Enger MD, Saponara AG. Incorporation of 14C from [2-14C]methionine into 18 s but not 28 s RNA of Chinese hamster cells. J Mol Biol 1968; 33:319-22. [PMID: 5646651 DOI: 10.1016/0022-2836(68)90298-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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