Effects of tocopherol depletion on muscle nucleic acid and creatine levels in the frog

1963 ◽  
Vol 204 (1) ◽  
pp. 168-170 ◽  
Author(s):  
Ross A. Gortner ◽  
Ann F. Milano

Groups of adult male frogs were force fed on diets either devoid of fat and tocopherols or containing "stripped" corn oil with or without added α-tocopherol for 120 days. At the end of this period histological examinations of the gastrocnemius muscles and testes revealed no signs of degeneration in any dietary group. Biochemical studies on the muscle gave no reflection of tocopherol deficiency in the levels or proportions of total ribonucleic acid and deoxyribonucleic acid but did show a marked lowering of total muscle creatine in frogs on the tocopherol-free diets. The deficient animals subjected to considerable amounts of the polyunsaturated corn oil exhibited the lowest creatine levels. It is concluded that the adult frog has a dietary requirement for vitamin E and that more prolonged deprivation probably would result in the dystrophic symptoms commonly noted in other species.

1962 ◽  
Vol 203 (4) ◽  
pp. 693-696 ◽  
Author(s):  
Thomas F. Necheles

Myeloid marrow was rapidly removed from femurs of fasting young rabbits, sectioned, and incubated in Krebs-bicarbonate-CO2-oxygen buffer with appropriate C14-labeled precursors. All manipulations were designed to preserve the architecture of the tissue. After 1 hr the protein or nucleic acid-adenine was isolated and purified. Insulin, 0.01 U/ml added in vitro, stimulated histidine-2(ring)-C14 incorporation into protein by 26 ± 1.4%; alkali-treated insulin was inactive. Thyroxin elicited a 49.4 ± 2.1% stimulation at an optimum concentration of 10–7 m. Triiodothyronine, but not diiodothyronine, also had a significant effect. Insulin increased incorporation of carbon from adenosine-8-C14 into adenine of ribonucleic acid and deoxyribonucleic acid. Thyroxin, on the other hand, was without consistent effect on this process. Thyroxin stimulated significantly the incorporation of C14 of glycine-2-C14 into adenine. The possibility that part of the anabolic effect of thyroxin on bone marrow may arise from a stimulus to incorporation of precursors into purines is suggested.


1962 ◽  
Vol s3-103 (61) ◽  
pp. 25-35
Author(s):  
H. WALLACE

A larval lethal mutant of Xenopus laevis lacks true nucleoli but possesses analogous intranuclear organelles, here termed blobs, which are smaller and more numerous than nucleoli. Cytochemical tests reveal that blobs (like nucleoli) contain ribonucleic acid (RNA), arginine, and alkaline phosphatase, but probably no Feulgen-positive material. Anucleolate larvae are deficient in cytoplasmic RNA. By biochemical methods the nucleic acid content of anucleolate embryos is found to be normal at the tail-bud stage, but does not increase after this. By the time they hatch, anucleolate larvae are deficient in both RNA and deoxyribonucleic acid (DNA). The implications of this and related mutations on the formation and function of the nucleolus are considered. The term ‘blob’ is justified in that it would be misleading to regard such organelles as nucleoli produced by normally latent organizers.


1959 ◽  
Vol 16 (4) ◽  
pp. 421-428 ◽  
Author(s):  
Vera M. Creelman ◽  
Neil Tomlinson

The quantity of ribonucleic acid phosphorus (RNA-P) and deoxyribonucleic acid phosphorus (DNA-P) in various tissues of the sockeye salmon has been determined at three points in its spawning migration. During migration a net decrease in RNA-P and a net increase in DNA-P occurred in the whole fish of both sexes. Major losses in RNA-P occurred in the flesh, alimentary tract and milt, while major gains in DNA-P occurred in the milt and roe. In the combined head, skin, bones and tail large gains in both RNA-P and DNA-P took place.


1976 ◽  
Vol 27 (5) ◽  
pp. 669 ◽  
Author(s):  
DA Little ◽  
LJ Lambourne

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.


1962 ◽  
Vol 25 (2) ◽  
pp. 183-NP ◽  
Author(s):  
W. B. JOLLEY ◽  
W. E. MARTIN ◽  
J. W. BAMBERGER ◽  
L. W. STEARNS

SUMMARY Oestradiol-17β at a concentration of 3 × 10−3 m inhibits cleavage in sea urchin (Strongylocentrotus purpuratus) embryos. This inhibition is accompanied by a reduction in deoxyribonucleic acid (DNA) synthesis and little change in ribonucleic acid (RNA). The effects of oestradiol-17β upon the incorporation of glycine-1-14C and glycine-2-14C into the purines of DNA and RNA and the incorporation of glycine-2-14C into serine were studied. The incorporation of glycine-1-14C and glycine-2-14C into RNA was reduced, but the incorporation of glycine-2-14C into DNA was increased considerably over that of the controls. The incorporation of glycine-2-14C into serine was also accelerated by oestradiol. A possible explanation of the action of oestradiol-17β is offered. The moderate effect upon RNA is not surprising because there is little or no synthesis of this compound from the time of fertilization to blastulation under normal conditions.


Author(s):  
A B McAllan ◽  
G D Braithwaite

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.


1956 ◽  
Vol 13 (4) ◽  
pp. 429-432 ◽  
Author(s):  
BARBARA J. GRAY

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.


Nucleotides are organic molecules, which are monomer units that form polymers of nucleic acid „deoxyribonucleic acid (DNA)‟ and „ribonucleic acid (RNA)‟. The four nucleotides A, T, G and C get connected by phosphodiester bonds to form strands. Strand formation depends on innumerable factors related to inter and intra cellular parameters and functions. One cannot precisely say that a particular strand gets formed using such and such rules. The infinite possibilities of strand formation cannot be determined experimentally or in the framework of classical genetics. One can alternatively formulate a notion of the “Language of Genomes” wherein one can finitely specify infinite strands. This paper introduces a novel prediction algorithm, which generates possible strands based on available nucleotides statistics.


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