scholarly journals The solution to the cytological paradox of isomorphy.

1987 ◽  
Vol 104 (3) ◽  
pp. 739-748 ◽  
Author(s):  
L J Goff ◽  
A W Coleman
Keyword(s):  
Cell Size ◽  
Dna Content ◽  
Nuclear Dna ◽  
Nuclear Dna Content ◽  
Plastid Dna ◽  
Diploid Cell ◽  
Red Alga ◽  
Haploid Nucleus ◽  
Two Generations ◽  
A Cell

Cells with polyploid nuclei are generally larger than cells of the same organism or species with nonpolyploid nuclei. However, no such change of cell size with ploidy level is observed in those red algae which alternate isomorphic haploid with diploid generations. The results of this investigation reveal the explanation. Nuclear DNA content and other parameters were measured in cells of the filamentous red alga Griffithsia pacifica. Nuclei of the diploid generation contain twice the DNA content of those of the haploid generation. However, all cells except newly formed reproductive cells are multinucleate. The nuclei are arranged in a nearly perfect hexagonal array just beneath the cell surface. When homologous cells of the two generations are compared, although the cell size is nearly identical, each nucleus of the diploid cell is surrounded by a region of cytoplasm (a "domain") nearly twice that surrounding a haploid nucleus. Cytoplasmic domains associated with a diploid nucleus contain twice the number of plastids, and consequently twice the amount of plastid DNA, than is associated with the domain of a haploid nucleus. Thus, doubling of ploidy is reflected in doubling of the size and organelle content of the domain associated with each nucleus. However, cell size does not differ between homologous cells of the two generations, because total nuclear DNA (sum of the DNA in all nuclei in a cell) per cell does not differ. This is the solution to the cytological paradox of isomorphy.

Developmental variability within and between mouse expanding blastocysts and their ICMs

Development ◽  
1985 ◽  
Vol 86 (1) ◽  
pp. 311-336
Author(s):  
Julia C. Chisholm ◽  
Martin H. Johnson ◽  
Paul D. Warren ◽  
Tom P. Fleming ◽  
Susan J. Pickering
Keyword(s):  
Cell Cycle ◽  
Cell Size ◽  
Dna Content ◽  
Nuclear Dna ◽  
Nuclear Dna Content ◽  
Cell Number ◽  
Developmental Potential ◽  
Present Evidence ◽  
Cell Cycling

We have attempted to reduce the developmental heterogeneity amongst populations of mouse blastocysts by synchronizing embryos to the first visible signs of blastocoel formation. Using embryos timed in this way, we have examined the extent of variation of inside and outside cell number and of inside cell size, nuclear DNA content and developmental potential, between and within embryos of a similar age postcavitation. The overall impression gained is one of wide heterogeneity in inside:outside cell number ratios and in cell cycling and its relation to cavitation among embryos of similar age postcavitation. However, the simplest explanation of our results suggests that cavitation generally begins at a time when most outside cells are in their sixth developmental cell cycle and that outside cells, as a population, are a little ahead of inside cells in their cell cycling. Additionally we present evidence that, within at least some individual inner cell masses (ICM), there is intraembryo variation in the time at which inside cell developmental potential becomes restricted.

scholarly journals Measurement of DNA content in single cells morphologically identified on smears.

1986 ◽  
Vol 34 (10) ◽  
pp. 1253-1255 ◽  
Author(s):  
N Maruo ◽  
T Nakabo ◽  
M Kondo
Keyword(s):  
Dna Content ◽  
Nuclear Dna ◽  
Single Cells ◽  
Green Light ◽  
Nuclear Dna Content ◽  
Absolute Methanol ◽  
Cell Populations ◽  
Bone Marrow Smear ◽  
Measuring Cell ◽  
A Cell

A method was developed for measuring the nuclear DNA content in single cells previously identified on a bone marrow smear stained by the Wright-Giemsa method. The smear was first photographed and the location of individual cells, identified by morphology, was recorded on a cell map. The smear was then bleached with 50% acid ethanol and absolute methanol, and re-stained by the Feulgen method in 0.05% pararosaniline Schiff's reagent (pH 2.3) at 7 degrees C for 10 min. Nuclear red fluorescence was observed and the intensity of this fluorescence was proportional to the amount of DNA after prior irradiation of smears with green light for 9 hr. The method is useful for measuring cell DNA content in heterogeneous cell populations when morphological cell identification is required.

Cannibals of Oxytricha bifaria (Ciliata, Hypotrichida). Macro- and micro-nuclear DNA content

1987 ◽  
Vol 65 (4) ◽  
pp. 847-851 ◽  
Author(s):  
Daniela C. Riggio ◽  
Nicola Ricci ◽  
Rosalba Banchetti ◽  
Hans Martin Seyfert
Keyword(s):  
Cell Differentiation ◽  
Giant Cell ◽  
Cell Size ◽  
Dna Content ◽  
Nuclear Dna ◽  
Physiological State ◽  
Nuclear Dna Content ◽  
Nuclear Size ◽  
Normal Value

Investigation of cell differentiation led us to study the giants of Oxytricha bifaria. Here we report systematic variations in nuclear DNA content. Comparing giants, controls starved for 10–14 days, and controls we conclude that (i) the amount of DNA is indicative of the occurrence of cell differentiation, while cell size or nuclear size is not; (ii) the macronuclear DNA content of a giant is about 3.7 times that of the controls; and (iii) the micronuclear DNA content of a giant is about 1.8 times that of the controls. The macronuclear DNA content declines throughout the four successive divisions which typically lead a giant cell back to the normal morpho-physiological state: the amount decreases steadily from a level of about 3.7 times the macronuclear DNA content of the controls to 2.57 and to 1.77 before dropping to 1.08, the normal value.

scholarly journals Nuclear DNA Content Varies with Cell Size across Human Cell Types

2015 ◽  
Vol 7 (7) ◽  
pp. a019091 ◽  
Author(s):  
James F. Gillooly ◽  
Andrew Hein ◽  
Rachel Damiani
Keyword(s):  
Cell Size ◽  
Human Cell ◽  
Dna Content ◽  
Nuclear Dna ◽  
Nuclear Dna Content ◽  
Cell Types

Prognostic value of nuclear DNA content in papillary and follicular thyroid cancer

1988 ◽  
Vol 12 (4) ◽  
pp. 503-507 ◽  
Author(s):  
Jaap F. Hamming ◽  
Lodewijk J. D. M. Schelfhout ◽  
Cees J. Cornelisse ◽  
Cornelis J. H. van de Velde ◽  
Bernard M. Goslings ◽  
...  
Keyword(s):  
Thyroid Cancer ◽  
Dna Content ◽  
Prognostic Value ◽  
Nuclear Dna ◽  
Nuclear Dna Content ◽  
Follicular Thyroid Cancer
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