Comparative studies on nucleic acid synthesis and virus-induced RNA polymerase activity in mammalian cells infected with certain arboviruses

1971 ◽  
Vol 34 (4) ◽  
pp. 266-277 ◽  
Author(s):  
M. Takehara
Keyword(s):  
Nucleic Acid ◽  
Rna Polymerase ◽  
Comparative Studies ◽  
Mammalian Cells ◽  
Acid Synthesis ◽  
Polymerase Activity ◽  
Nucleic Acid Synthesis ◽  
Rna Polymerase Activity

scholarly journals 8-AZAGUANINE RESISTANCE IN MAMMALIAN CELLS I. HYPOXANTHINE-GUANINE PHOSPHORIBOSYLTRANSFERASE

Genetics ◽  
1972 ◽  
Vol 72 (2) ◽  
pp. 239-252 ◽  
Author(s):  
F D Gillin ◽  
D J Roufa ◽  
A L Beaudet ◽  
C T Caskey
Keyword(s):  
Nucleic Acid ◽  
Mammalian Cells ◽  
Chinese Hamster ◽  
Acid Synthesis ◽  
Ethyl Methanesulfonate ◽  
Nucleic Acid Synthesis ◽  
Wild Type ◽  
Chinese Hamster Cells ◽  
Hypoxanthine Guanine Phosphoribosyltransferase

ABSTRACT Chinese hamster cells were treated with ethyl methanesulfonate or N-methyl-N'-nitro-N-nitrosoguanidine, and mutants resistant to 8-azaguanine were selected and characterized. Hypoxanthine-guanine phosphoribosyltransferase activity of sixteen mutants is extremely negative, making them suitable for reversion to HGPRTase+. Ten of the extremely negative mutants revert at a frequency higher than 10-7 suggesting their point mutational character. The remaining mutants have demonstrable HGPRTase activity and are not useful for reversion analysis. Five of these mutants have < 2% HGPRTase and are presumably also HGPRTase point mutants. The remaining 14 mutants utilize exogenous hypoxanthine for nucleic acid synthesis poorly, and possess 20-150% of wild-type HGPRTase activity in in vitro. Their mechanism of 8-azaguanine resistance is not yet defined.

scholarly journals Transcription of brain chromatin by ribonucleic acid polymerases from brain nucleic and from Escherichia coli

1972 ◽  
Vol 130 (4) ◽  
pp. 1095-1099 ◽  
Author(s):  
Vijendra K. Singh ◽  
S. C. Sung
Keyword(s):  
Escherichia Coli ◽  
Rna Polymerase ◽  
Rna Polymerase Ii ◽  
Mammalian Cells ◽  
Transcriptional Control ◽  
Polymerase Activity ◽  
Control Mechanisms ◽  
E Coli ◽  
Bacterial Enzyme ◽  
Rna Polymerase Activity

1. Transcription of ox brain chromatin by brain nuclear RNA polymerase II and Escherichia coli RNA polymerase was studied. 2. The soluble chromatin prepared from brain nuclei contained DNA, RNA, histone and non-histone proteins. Such chromatin preparations did not display any endogenous RNA polymerase activity, when assayed in the presence of concentrations of KCl as high as 0.4m. 3. The chromatin-templated activity of brain nuclear polymerase II was stimulated by KCl, with an optimum around 0.25m. 4. The template activity of brain chromatin for brain nuclear polymerase II and E. coli enzyme was about 20–25% of that of pure DNA. This greatly repressed templatecapacity of chromatin was probably due to the acid-soluble chromosomal proteins. 5. Brain nuclear polymerase II was 3–4 times more active with dehistonized chromatin than with pure DNA as template, whereas bacterial enzyme was almost equally active with either of these two templates, reflecting the specificity of the transcriptional control mechanisms in mammalian cells.

Nucleic Acid Synthesis and the Mitotic Cycle in Mammalian Cells Treated with Nitrogen Mustard in Culture

Nature ◽  
1965 ◽  
Vol 207 (4997) ◽  
pp. 608-610 ◽  
Author(s):  
A. G. LEVIS ◽  
G. A. DANIELI ◽  
E. PICCINNI
Keyword(s):  
Nucleic Acid ◽  
Mammalian Cells ◽  
Mitotic Cycle ◽  
Nitrogen Mustard ◽  
Acid Synthesis ◽  
Nucleic Acid Synthesis

scholarly journals NAD+, ADP-ribosylation and transcription in permeabilized mammalian cells

1981 ◽  
Vol 199 (3) ◽  
pp. 813-817 ◽  
Author(s):  
J Walker ◽  
C K Pearson
Keyword(s):  
Rna Polymerase ◽  
Mammalian Cells ◽  
Inhibitory Effect ◽  
Polymerase Activity ◽  
Rna Polymerase I ◽  
Permeabilized Cells ◽  
Adp Ribosylation ◽  
Deoxyribonuclease I ◽  
Rna Polymerase Activity ◽  
Polymerase I

When permeabilized hamster fibroblasts were incubated with 4 mM-NAD+, the substrate for poly(ADP-ribose) polymerase, RNA polymerase I activity was inhibited by about 85%. This inhibition was not relieved by prior incubation of cells with 3-aminobenzamide, a potent inhibitor of the poly(ADP-ribose) polymerase. Digestion of cells with pancreatic deoxyribonuclease I resulted in the inhibition of RNA polymerase I by 80% and the activation of poly(ADP-ribose) polymerase by up to 300%; prior incubation with 3-aminobenzamide did not prevent the inhibition of the RNA polymerase activity. No radioactivity was found associated with RNA polymerase I during later stages of purification of this enzyme from permeabilized cells previously incubated with [14C]NAD+. The inhibitory effect of NAD+ on RNA polymerase I was not specific for NAD+, as other small, negatively charged molecules with a nuclear location also inhibited the enzyme. The results do not support the concept of a role for ADP-ribosylation in transcription catalysed by RNA polymerase I.

scholarly journals Influence of irofulven, a transcription-coupled repair-specific antitumor agent, on RNA polymerase activity, stability and dynamics in living mammalian cells

2008 ◽  
Vol 121 (8) ◽  
pp. 1275-1283 ◽  
Author(s):  
A. E. Escargueil ◽  
V. Poindessous ◽  
D. G. Soares ◽  
A. Sarasin ◽  
P. R. Cook ◽  
...  
Keyword(s):  
Rna Polymerase ◽  
Mammalian Cells ◽  
Antitumor Agent ◽  
Polymerase Activity ◽  
Rna Polymerase Activity ◽  
Transcription Coupled Repair

A Possible Role of Lipids in RNA Polymerase from Mammalian Cells

1972 ◽  
Vol 50 (7) ◽  
pp. 807-812 ◽  
Author(s):  
I. A. Menon
Keyword(s):  
Rna Polymerase ◽  
Phospholipase D ◽  
Mammalian Cells ◽  
Polymerase Activity ◽  
Ionic Concentration ◽  
Phospholipase A ◽  
Rat Tissues ◽  
Rna Polymerase Activity ◽  
Liver Nuclei

The effects of treatment with phospholipases and extraction with solvents on the activities of RNA polymerases from several rat tissues were studied. The RNA polymerase activity of particulate enzyme from rat liver nuclei was decreased by pretreatment of the enzyme with phospholipase A. The phospholipase decreased the RNA polymerase activity in presence of Mg2+ but not that in presence of Mn2+. The effect of phospholipase A was observed only at low ionic concentration. When the RNA polymerase activity was determined in presence of ammonium sulfate, KCl, or NaCl, phospholipase A did not decrease the RNA polymerase activity. Extraction of the RNA polymerase with ether or iso-octane decreased the RNA polymerase activity to approximately the same extent as the pretreatment with phospholipase A. Phospholipase C produced similar changes as phospholipase A but phospholipase D and lipase did not have any effect on the RNA polymerase activity. Treatment with phospholipase A as well as extraction with solvents enhanced the activity of chromatin-bound RNA polymerase from rat brain, and the RNA polymerase activities of similar preparations from spleen, kidney, heart, and lung were affected only to a relatively smaller extent.

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