Some histochemical changes underlying shoot initiation in tobacco callus cultures

1970 ◽  
Vol 48 (2) ◽  
pp. 277-285 ◽  
Author(s):  
Trevor A. Thorpe ◽  
Toshio Murashige
Keyword(s):  
Nucleic Acids ◽  
Ribonucleic Acid ◽  
Acid Content ◽  
Deoxyribonucleic Acid ◽  
Histochemical Study ◽  
Callus Cultures ◽  
Tobacco Callus ◽  
Apparent Change ◽  
Shoot Initiation ◽  
Histochemical Changes

A comparative histochemical study of changes in nucleic acids, proteins, and carbohydrates was performed on freeze-substituted samples of tobacco callus, cultured under shoot-forming and non-organ-forming conditions. The DNA (deoxyribonucleic acid) content per cell showed no apparent change, whereas denser staining for RNA (ribonucleic acid) and protein were observed in shoot-forming regions just before and during the initiation of organized structures. The most dramatic finding was the heavy accumulation of starch in shoot-forming tissue; this accumulation preceded any organ formation and was mainly in regions which ultimately gave rise to primordia.

Changes in the nucleic acid content of the uterus of sheep during involution following ovariectomy and following oestrogenic stimulation

1976 ◽  
Vol 27 (5) ◽  
pp. 669 ◽  
Author(s):  
DA Little ◽  
LJ Lambourne
Keyword(s):  
Nucleic Acid ◽  
Nucleic Acids ◽  
Ribonucleic Acid ◽  
Acid Content ◽  
Deoxyribonucleic Acid ◽  
Total Content ◽  
Mean Value ◽  
Nucleic Acid Content ◽  
Uterine Tissue ◽  
Rna Concentration

The concentrations of nucleic acids, deoxyribonucleic acid (DNA) and ribonucleic acid (RNA), in ovine uterine tissue were studied to determine whether the ratio RNA/DNA might be used in the bioassay of oestrogenic activity. As the uterus decreased in size with time after ovariectomy, the concentration of DNA increased markedly, but the total content of DNA in the uterus remained constant (mean value 342 ? 8 (SE) mg). The RNA concentration of the tissue decreased during involution, with the result that a highly significant reduction of 33% in the RNA/DNA ratio occurred within 2 weeks of ovariectomy. The ratio decreased further with time. Other ewes were treated for 3 days with diethylstilboestrol dipropionate (10 µg/day), commencing 2 weeks after ovariectomy; the stage of the oestrous cycle at which the ovaries were removed had no effect on the response to the oestrogen. Changes in the nucleic acid concentrations in the uteri of these ewes, and the results obtained during involution, indicate that the RNA/DNA ratio of uterine tissue in ovariectomized ewes has potential as a basis for the bioassay of materials of low oestrogenic potency.

THE EFFECT OF LARGE DOSES OF THIOUREA ON THE COMPOSITION OF THE LIVER AND URINE OF RATS

1956 ◽  
Vol 13 (2) ◽  
pp. 141-149 ◽  
Author(s):  
F. DOLJANSKI ◽  
Z. ESHKOL ◽  
D. GIVOL ◽  
E. KAUFMANN ◽  
E. MARGOLIASH
Keyword(s):  
Uric Acid ◽  
Urinary Excretion ◽  
Ribonucleic Acid ◽  
Acid Content ◽  
Catalase Activity ◽  
Deoxyribonucleic Acid ◽  
Liver Weight ◽  
Liver Glycogen ◽  
Chemical Changes ◽  
Thiourea Treatment

SUMMARY Following the observation that large daily doses of thiourea induced numerous mitoses in the liver of rats [Rachmilewitz, Rosin & Doljanski, 1950], the concomitant chemical changes in the liver and urine of thiourea-treated rats were investigated. It was found that: (1) The mitogenetic reaction, which occurred on the 3rd day of treatment with the drug, was preceded by (a) a decrease in liver catalase activity to 30–50% of the normal within 12 hr; (b) an increase in total liver weight and concentration of liver ribonucleic acid within 2 days. The enlarged liver was normal with respect to protein, lipid, water and deoxyribonucleic acid content. (2) The concentration of liver glycogen decreased markedly on the 1st day of thiourea treatment but returned to normal by the 2nd or 3rd day. (3) During the period of treatment with thiourea there was an increase in the urinary excretion of uric acid, allantoin, and phosphate, as well as glucosuria and polyuria. There was no change in the excretion of urea and total sulphate. (4) All these changes, both in the liver and the urine, were fully reversible on withdrawing the drug.

scholarly journals Effect of denervation on the synthesis of ribonucleic acid and deoxyribonucleic acid in rat diaphragm muscle

1968 ◽  
Vol 108 (2) ◽  
pp. 177-183 ◽  
Author(s):  
K L Manchester ◽  
E J Harris
Keyword(s):  
Nucleic Acids ◽  
Ribonucleic Acid ◽  
Orotic Acid ◽  
Deoxyribonucleic Acid ◽  
Diaphragm Muscle ◽  
Unit Mass ◽  
Rat Diaphragm ◽  
The Third

1. The effect of unilateral denervation of rat diaphragm muscle on its content of nucleic acids and their incorporation of precursors was investigated. 2. After denervation the paralysed hemidiaphragm hypertrophies and within 3 days its content of RNA increases considerably. The concentration of DNA/unit mass remains fairly constant. 3. During this period there is some increase in the rate of incorporation of [14C]adenine into RNA, whereas there is some diminution in the rate of incorporation of [14C]orotic acid. 4. Incorporation of [14C]adenine and [3H]thymidine into DNA is much increased in the paralysed tissue, reaching its maximum by about the third day, but returning to normal by the tenth. 5. The significance of these results in relation to the hypertrophy after denervation is discussed.

Nucleic Acids in Grass and Grass Silage

1988 ◽  
Vol 1988 ◽  
pp. 86-86
Author(s):  
A B McAllan ◽  
G D Braithwaite
Keyword(s):  
Nucleic Acid ◽  
Nucleic Acids ◽  
Protein Content ◽  
Ribonucleic Acid ◽  
Protein Fraction ◽  
Dry Matter ◽  
Deoxyribonucleic Acid ◽  
Total N ◽  
Grass Silage ◽  
Microbial N

Little attention has been directed at defining the ‘protein’ fraction of silages. This component is normally estimated by fractionation based on solubility characteristics and under the conditions most commonly used, nucleic acids (ribonucleic acid (RNA) and deoxyribonucleic acid (DNA)) would appear in the protein fraction. Grasses and legumes can contain appreciable amounts of nucleic acids ranging from 11-29 and 19-53 g/kg dry matter respectively (McAllan, 1982). No information is available as to the effects of ensilage on these nucleic acids. Microbes also contain appreciable amounts of nucleic acids which can account for 150-200 gN/kg total-N of the cell and these amounts may vary according to the stage of growth. It has been suggested (Ullrich, 1982) that microbial-N contribution to the total-N content of silage is as much as 220-280 g/kg. Thus the total amount of silage ‘protein-N’ present in the form of nucleic acid-N (from both plant and microbes) could be appreciable leading to a considerable overestimation of the ‘protein’ content of the silage.

THE INFLUENCE OF GROWTH HORMONE ON THE NUCLEIC ACID CONTENT OF RAT LIVER AND MUSCLE

1956 ◽  
Vol 13 (4) ◽  
pp. 429-432 ◽  
Author(s):  
BARBARA J. GRAY
Keyword(s):  
Skeletal Muscle ◽  
Growth Hormone ◽  
Nucleic Acid ◽  
Rat Liver ◽  
Ribonucleic Acid ◽  
Acid Content ◽  
Deoxyribonucleic Acid ◽  
Female Rats ◽  
Nucleic Acid Content ◽  
Pituitary Growth Hormone

SUMMARY Adult female rats were treated with purified pituitary growth hormone for 9 days, and the nucleic acid content of the liver and skeletal muscle determined. An increase was observed in the concentration of muscle ribonucleic acid, expressed per gram of nitrogen, as a result of the treatment. There were no changes in the ribonucleic acid concentration of liver. No changes were observed in the concentration of deoxyribonucleic acid in muscle or liver.

Composition of Methanospirillum hungatii GP1 during growth on different media

1980 ◽  
Vol 26 (5) ◽  
pp. 577-582 ◽  
Author(s):  
C. Breuil ◽  
G. B. Patel
Keyword(s):  
Protein Content ◽  
Ribonucleic Acid ◽  
Acid Content ◽  
Deoxyribonucleic Acid ◽  
Synthetic Medium ◽  
Density Measurement ◽  
Dry Weight ◽  
Weight Basis ◽  
Total Carbohydrate ◽  
Mineral Salts

Growth of Methanospirillum hungatii GP1 as determined by optical density measurement was comparable to growth assessed by cell dry weight, ribonucleic acid content, and deoxyribonucleic acid content. Cultivation of M. hungatii on synthetic medium containing mineral salts, vitamins, and acetic acid indicated that, on a dry weight basis, cell constituents such as protein (71%), ribonucleic acid (15.8%), deoxyribonucleic acid (1.6%), and total carbohydrate (3.2%) did not vary significantly with the growth phase. Cells grown in the synthetic medium supplemented with yeast extract and tryptone had slightly higher protein content (76%), but the concentrations of the other cell constituents were similar and did not fluctuate much during growth. Nitrogen limiting growth resulted in somewhat lower ribonucleic acid content as well as slightly higher protein content than that in cells grown in nonlimiting medium. Methanospirillum hungatii did not accumulate any of the commonly known reserve materials under nitrogen or carbon and hydrogen limiting growth.

scholarly journals Nucleic Acids and the Biosynthesis of Collagen

1957 ◽  
Vol 10 (3) ◽  
pp. 398 ◽  
Author(s):  
PH Springell
Keyword(s):  
Nucleic Acids ◽  
Ribonucleic Acid ◽  
Deoxyribonucleic Acid ◽  
Protein Fractions ◽  
Marked Inhibition ◽  
In Vitro Incubation ◽  
Skin Protein ◽  
Pre Treatment ◽  
Salt Fractionation

The study of skin protein fractions obtained by salt fractionation indicates that collagen is associated to a greater extent with the ribonucleoprotein fraction than with the deoxyribonucleoprotein fraction. The gelatin derived from the ribonucleoprotein fraction following in vitro incubation of foetal lambskin in the presence of glycine-2-14C was appreciably radioactive. Pre-treatment of the skin with crystalline ribonuclease resulted in a marked inhibition of glycine incorporation into total gelatin. whereas crystalline deoxyribonuclease had little effect. It is therefore concluded that ribonucleic acid rather than deoxyribonucleic acid is associated with the biosynthesis of collagen.

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