The Degradation of Newly Synthesized RNA in Ehrlich Ascites Tumor Cells

1973 ◽  
Vol 51 (5) ◽  
pp. 495-505 ◽  
Author(s):  
Richard G. von Tigerstrom
Keyword(s):  
Tumor Cells ◽  
Rna Synthesis ◽  
Actinomycin D ◽  
Ehrlich Ascites Tumor ◽  
Ehrlich Ascites Tumor Cells ◽  
Ascites Tumor ◽  
Ehrlich Ascites ◽  
Ehrlich Ascites Cells ◽  
The Stability

The stability of rapidly labelled RNA in Ehrlich ascites tumor cells under in vitro conditions was investigated. [2-14C]Uridine was effectively incorporated into RNA and 90% of the acid-insoluble isotope was associated with the nucleus after 30 min labelling. When RNA synthesis was inhibited by actinomycin D or when [14C]uridine was chased with [12C]uridine at this time, a rapid degradation of approximately 50% of the labelled RNA could be observed. The rates of degradation, the extent of degradation under certain incubation conditions, and the classes of RNA from which the isotope was released were almost identical when the two chase techniques were compared. The concentration of uridine used during the chase did not inhibit RNA synthesis significantly as judged from incorporation of [8-14C]guanine. The results indicated that the degradation of the newly synthesized RNA in Ehrlich ascites cells occurred naturally and was not induced by actinomycin D.

Effects of Actinomycin D on Purine Ribonucleotide Metabolism in Ehrlich Ascites Tumor Cells In Vitro

1974 ◽  
Vol 52 (3) ◽  
pp. 263-267 ◽  
Author(s):  
Floyd F. Snyder ◽  
J. Frank Henderson
Keyword(s):  
Tumor Cells ◽  
Actinomycin D ◽  
De Novo ◽  
Acid Synthesis ◽  
Purine Metabolism ◽  
Ehrlich Ascites Tumor ◽  
Ehrlich Ascites Tumor Cells ◽  
Ascites Tumor ◽  
Ehrlich Ascites

Actinomycin D treatment of Ehrlich ascites tumor cells in vitro causes slight to moderate inhibition of purine ribonucleotide synthesis de novo and from purine bases, and strong inhibition of inosinate dehydrogenase activity. These effects have the same dose–response relationship as inhibition of RNA synthesis by this drug. Daunomycin has similar effects on purine metabolism at a concentration that substantially inhibits nucleic acid synthesis. Actinomycin D treatment leads to elevated intracellular concentrations of ATP and GTP, and the effects of this drug on purine metabolism are believed to be mediated by these purine ribonucleoside triphosphates.

Effects of Bikaverin on purine nucleotide synthesis and catabolism in ehrlich ascites tumor cells in vitro

1977 ◽  
Vol 26 (21) ◽  
pp. 1973-1977 ◽  
Author(s):  
J.Frank Henderson ◽  
Mary L. Battell ◽  
George Zombor ◽  
Jan Fuska ◽  
P. Nemec
Keyword(s):  
Tumor Cells ◽  
Ehrlich Ascites Tumor ◽  
Purine Nucleotide ◽  
Ehrlich Ascites Tumor Cells ◽  
Ascites Tumor ◽  
Nucleotide Synthesis ◽  
Ehrlich Ascites

NUCLEIC ACTD METABOLISM IN INTESTINAL MUCOSA: IV. THE EFFECT OF GLUCOSE ON INCORPORATION OF C14-FORMATE INTO PURINES AND PYRIMIDINES IN VITRO

1963 ◽  
Vol 41 (1) ◽  
pp. 1557-1564
Author(s):  
Beryl E. Stewart ◽  
S. H. Zbarsky
Keyword(s):  
Tumor Cells ◽  
Ehrlich Ascites Tumor ◽  
Ehrlich Ascites Tumor Cells ◽  
Ascites Tumor ◽  
Rat Intestine ◽  
Maximal Stimulation ◽  
Ehrlich Ascites ◽  
Effect Of Glucose ◽  
Rna And Dna

Slices of rat intestine were incubated in Krebs–Ringer phosphate buffer in the presence of C14-formate. The addition of glucose to the buffer stimulated the incorporation of radioactivity into the purines and, in some instances, the pyrimidines of the acid-soluble fraction and nucleic acids of the tissue. With Ehrlich ascites tumor cells studied under similar conditions, the increase in uptake of C14-formate into the purines was somewhat greater. The data suggest also that maximal stimulation with slices of intestine is obtained at glucose concentrations somewhat higher than that required with Ehrlich ascites tumor cells. A finding of interest was the increased incorporation of C14-formate into the thymine of the intestinal DNA in the presence of glucose. This result has not been observed with Ehrlich ascites tumor cells. Slices of rat intestine incubated for 2 hours in the presence of glucose had a higher content of RNA and DNA than tissue not exposed to added glucose.

Growth acceleration of Ehrlich ascites tumor cells treated by proteinase in vitro

1989 ◽  
Vol 25 (12) ◽  
pp. 1837-1841 ◽  
Author(s):  
Irenäus A. Adamietz ◽  
Fritz Kurfürst ◽  
Ulrich Müller ◽  
Karlheinz Renner ◽  
Manfred Rimpler
Keyword(s):  
Tumor Cells ◽  
Ehrlich Ascites Tumor ◽  
Ehrlich Ascites Tumor Cells ◽  
Ascites Tumor ◽  
Ehrlich Ascites

ENHANCEMENT OF RIBONUGLEOSIDE SYNTHESIS IN EHRLICH ASCITES TUMOR CELLS BY ARSENATE AND IODOACETATE

1965 ◽  
Vol 43 (10) ◽  
pp. 1693-1700 ◽  
Author(s):  
A. R. P. Paterson ◽  
A. I. Simpson
Keyword(s):  
Tumor Cells ◽  
Incubation Medium ◽  
Ehrlich Ascites Tumor ◽  
Ehrlich Ascites Tumor Cells ◽  
Ascites Tumor ◽  
Rapid Exchange ◽  
Ribose Phosphate ◽  
Ehrlich Ascites ◽  
Lactate Formation

Ehrlich ascites tumor ceils in vitro synthesize ribonucleosides, which appear mainly in the incubation medium, by the transfer of ribose from a donor ribonucleoside to an acceptor base. In the present study, it was found that the rates of synthesis of inosine and uridine in this system were markedly enhanced in the presence of arsenate or iodoacetate. The exchange of isotope between extracellular inosine and hypoxanthine-8-C14 was similarly enhanced by arsenate, but the more rapid exchange between uridine and uracil-2-C14 was unaffected. Arsenate did not cause changes in the rates of uridine breakdown that would account for the enhanced rate of nucleoside synthesis and did not promote the release of nucleoside-synthesizing enzymes from the tumor cells into the incubation medium. Because lactate formation during the uridine-supported synthesis of inosine was markedly inhibited by arsenate and iodoacetate, the increase in ribonucleoside synthesis appears to be indirect and to be related to inhibition of ribose phosphate catabolism.

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