Measuring murine chromosome orientation in interphase nuclei

The uptake of tritiated thymine into cells of a heterogeneous population of Prorocentrum micans was investigated using light-microscope and electron-microscope autoradiography. Specificity of thymine uptake into DNA was demonstrated by the specific removal of label from wax-embedded material using DNase and by the high degree of localization of nuclear label to chromosomes in the electron-microscope autoradiographs. All nuclei, including both dividing and non-dividing cells, showed a substantial uptake of label, indicating that nuclear DNA synthesis in Prorocentrum micans is a continuous process. The level of DNA synthesis does show considerable variation, however, with very high levels in some interphase nuclei. The continuous replication of nuclear DNA provides further evidence of dinoflagellate affinity to the prokaryotes, and indicates that Prorocentrum micans is a very primitive eukaryote cell.

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Fine structure of the haplosporidan Kernstab, a persistent, intranuclear mitotic apparatus

Journal of Cell Science ◽

10.1242/jcs.18.2.327 ◽

1975 ◽

Vol 18 (2) ◽

pp. 327-346

Author(s):

F.O. Perkins

Keyword(s):

Fine Structure ◽

Nuclear Envelope ◽

Light Microscope ◽

Spindle Pole Body ◽

Spindle Pole ◽

Interphase Nuclei ◽

Mitotic Apparatus ◽

Pole Body

The fine structure of the haplosporidan mitotic apparatus is described from observations of plasmodial nuclei of Minchinia nelsoni, M. costalis, Minchinia sp., and Urosporidium crescens. The apparatus, which is the Kernstab of light-microscope studies, consists of a bundle of microtubules terminating in a spindle pole body (SPB) at each end of the bundle. A few microtubules extend from SPB to SPB, but most either extend from an SPB and terminate in the nucleoplasm or lie in the nucleoplasm, free of either SPB. The bundle lengthens during mitosis, increasing the SPB-to-SPB distance by a factor of 2 to 3 as compared to interphase nuclei. SPBs are not in contact with the nuclear envelope, being found always in the nucleoplasm which is delimited by the nuclear envelope throughout mitosis. The mitotic apparatus is persistent through interphase, at least in a form which is not significantly different from that found in mitotic nuclei.

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The Synthesis and Migration of Nuclear Proteins during Mitosis and differentiation of Cells in Rats

Journal of Cell Science ◽

10.1242/jcs.s3-106.75.229 ◽

1965 ◽

Vol s3-106 (75) ◽

pp. 229-240

Author(s):

R. T. SIMS

Keyword(s):

Granular Cell ◽

Nuclear Proteins ◽

Photographic Emulsion ◽

Metaphase Chromosomes ◽

Interphase Nuclei ◽

Cell Layers ◽

The Difference ◽

Mitotic Figures ◽

And Migration ◽

Silver Grains

Hooded rats were given an intraperitoneal injection of 3H-tyrosine, and killed in pairs 10 min, 30 min, 12 h, 36 h, 7 days, and 30 days later. A piece of skin with white growing hair, and the tongue, were taken from each animal and radioautographs were prepared. Silver grains were counted over whole nuclei and whole mitotic figures of the germinal cells and whole nuclei of differentiating cells of both tissues. It was found that the interphase nuclei have significantly more silver grains over them than the chromosomes at all stages of mitosis and there are virtually no grains over metaphase, anaphase, and early telophase chromosomes in both tissues of all the animals killed up to 36 h after the injection. The difference between the grain counts over the interphase nuclei and the chromosomes of dividing cells is at least 20-fold at 30 min in the hair matrix, at least 5-fold at 30 min in the tongue and at 36 h in both tissues. It was established that the differences observed between the radioactivities of the nuclei and chromosomes of mitotic figures are real from estimates of: the radioactivity of the cell cytoplasm, volumes of the metaphase chromosomes and interphase nuclei within 1µ of the photographic emulsion, and the volumes of cytoplasm separating the photographic emulsion and these structures. No protein synthesis was demonstrable in the chromosomes during metaphase, anaphase, and early telophase. Nuclear proteins leave the chromosomes during prophase and prometaphase and return to the nucleus during late telophase. The cells in the matrix and upper bulb of the growing hair follicle and those in the germinal, prickle, and granular cell layers of the tongue are in different functional states; 30 min after injection of 3H-tyrosine they have different amounts of it in their nuclear proteins. It is suggested that the amount incorporated into each nucleus is related to the rate at which proteins are being synthesized by the cell.

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Characterization of eight species of Aloe (Asphodelaceae) from the nucleolar organizing region

Rodriguésia ◽

10.1590/2175-7860201869208 ◽

2018 ◽

Vol 69 (2) ◽

pp. 363-372

Author(s):

Ysbelia Sánchez-G ◽

María B. Raymúndez ◽

José Imery ◽

M. Cristina Acosta ◽

Eduardo Moscone

Keyword(s):

Subtelomeric Region ◽

Interphase Nuclei ◽

Nucleolar Organizing Region ◽

Subtelomeric Regions

Abstract Nucleolar organizing region of eight species of Aloe was analyzed in somatic metaphases and interphase nuclei. All species showed a uniform 2n=14, with eight large chromosomes and six small chromosomes. Satellites were observed on the long arm of one or two pairs of large chromosomes and/or on the short arm of one of the small pairs. The silver-stained nucleolus organizing regions were located on the subtelomeric region of the long arm of one or two pairs of large chromosomes, except for Aloe dichotoma and Aloe maculata, which the AgNORs were located at a short arm of one of their small chromosomes. In most studied species, the active AgNOR number was four. However, this number changing from one to eight. For all species, the interphase number of nucleoli can be one or two, while, in Aloe excelsa, this number can be changing from one to eight. Polymorphism of active AgNORs and the number of interphase nucleoli were revealed, except for Aloe petricola, which active AgNORs were located only in the subtelomeric regions at the long arm of one of the L2 chromosomes, as well as in the L4 pair, which is agrément with the maximum number (three) of interphase nucleoli.

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Nuclear proteins of quiescent and mitotically active cells in shoot meristems of Tradescantia paludosa

Canadian Journal of Botany ◽

10.1139/b74-263 ◽

1974 ◽

Vol 52 (9) ◽

pp. 2049-2053 ◽

Cited By ~ 5

Author(s):

R. S. Tobin ◽

Kyu-Byung Yun ◽

J. M. Naylor

Keyword(s):

Nuclear Proteins ◽

Zone Of Inhibition ◽

Interphase Nuclei ◽

Lateral Buds ◽

Dye Binding ◽

Tradescantia Paludosa ◽

Shoot Meristems

In inhibited lateral buds of Tradescantia paludosa, interphase nuclei in the apical zone of inhibition contain higher levels of arginine per unit DNA than those of mitotically active cells in interphase or prophase. Supplementary dye-binding experiments suggest that this reflects a corresponding difference between the composition of the histone complement of chromatin in the two cells populations. The possible implications of this phenomenon are discussed.

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Demonstration of the translocation der(16)t(1;16)(q12;q11.2) in interphase nuclei of ewing tumors

Genes Chromosomes and Cancer ◽

10.1002/(sici)1098-2264(199611)17:3<141::aid-gcc1>3.0.co;2-4 ◽

1996 ◽

Vol 17 (3) ◽

pp. 141-150 ◽

Cited By ~ 27

Author(s):

Claudia M. Hattinger ◽

Silvia Rumpler ◽

Inge M. Ambros ◽

Sabine Strehl ◽

Thomas Lion ◽

...

Keyword(s):

Interphase Nuclei ◽

Ewing Tumors

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Mitotic chromatin condensation in vitro using somatic cell extracts and nuclei with variable levels of endogenous topoisomerase II.

The Journal of Cell Biology ◽

10.1083/jcb.111.6.2839 ◽

1990 ◽

Vol 111 (6) ◽

pp. 2839-2850 ◽

Cited By ~ 101

Author(s):

E R Wood ◽

W C Earnshaw

Keyword(s):

Topoisomerase Ii ◽

Condensation Reaction ◽

Chromatin Condensation ◽

Condensation Process ◽

Interphase Nuclei ◽

Culture Cells ◽

Cell Extracts ◽

Topo Ii ◽

Species Specific

We report the development of a new method for producing mitotic extracts from tissue culture cells. These extracts reproducibly promote the condensation of chromatin in vitro when incubated with purified interphase nuclei. This condensation reaction is not species specific, since nuclei from chicken, human, and hamster cell lines all undergo chromatin condensation upon incubation with the extract. We have used this extract to investigate the role of DNA topoisomerase II (topo II) in the chromosome condensation process. Chromatin condensation does not require the presence of soluble topo II in the mitotic extract. However, the extent of formation of discrete chromosome-like structures correlates with the level of endogenous topo II present in the interphase nuclei. Our results further suggest that chromatin condensation in this extract may involve two processes: chromatin compaction and resolution into discrete chromosomes.

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