RNA Polymerase Stimulation: Effect of Aldosterone and Other Adrenocorticoids on RNA Turnover in Rat Kidney

1975 ◽  
Vol 53 (1) ◽  
pp. 70-78 ◽  
Author(s):  
Ram K. Mishra ◽  
L. A. W. Feltham
Keyword(s):  
Endoplasmic Reticulum ◽  
Rna Polymerase ◽  
Smooth Endoplasmic Reticulum ◽  
Rat Kidney ◽  
Polymerase Activity ◽  
Daily Administration ◽  
Aldosterone Receptor ◽  
Rna Polymerase Activity ◽  
Adrenocortical Hormone ◽  
Dna Template

The results of steroid hormone stimulation of aggregate RNA polymerase activity in kidney can be interpreted in terms of either template or enzyme alterations. In order to discover the effect of aldosterone on enzyme or DNA template, the RNA polymerases were purified from kidney nuclei of normal, adrenalectomized or adrenalectomized plus aldosterone treated rats and the activity was determined using different sources of DNA. It was found that the DNA from aldosterone treated rats was transcribed more efficiently than from other sources. Aldosterone does not seem to have a direct effect on the RNA polymerase. Fractionation of ([14C]aldosterone injected) kidney chromatin revealed the presence of radioactivity in the non-histone acidic proteins and DNA, suggesting the possible binding of aldosterone or aldosterone–receptor complex to these chromatin fractions which may result in enhanced template activity.Turnover of RNA was also studied in various subcellular fractions: nuclei, mitochondria, rough endoplasmic reticulum, smooth endoplasmic reticulum, polysomes, ribosomes and sRNA, in normal, adrenalectomized, and adrenalectomized plus adrenocortical hormone treated rat kidney, by following the loss of radioactivity after a single injection of [14C]-orotic acid. Daily administration of aldosterone or deoxycorticosterone reversed the effects of adrenalectomy. Daily administration of corticosterone was without effect.

scholarly journals Mechanism of inhibition of Escherichia coli RNA polymerase by captan

1982 ◽  
Vol 201 (1) ◽  
pp. 145-151 ◽  
Author(s):  
J W Dillwith ◽  
R A Lewis
Keyword(s):  
Escherichia Coli ◽  
Rna Polymerase ◽  
Rna Synthesis ◽  
Polymerase Activity ◽  
Mechanism Of Inhibition ◽  
Dna Binding Site ◽  
Rna Polymerase Activity ◽  
Dna Template ◽  
Template Dna

Captan (N-trichloromethylthiocyclohex-4-ene-1,2-dicarboximide) was shown to inhibit RNA synthesis in vitro catalysed by Escherichia coli RNA polymerase. Incorporation of [gamma-32P]ATP and [gamma-32P]GTP was inhibited by captan to the same extent as overall RNA synthesis. The ratio of [3H]UTP incorporation to that of [gamma-32P]ATP or of [gamma-32P]GTP in control and captan-treated samples indicated that initiation was inhibited, but the length of RNA chains being synthesized was not altered by captan treatment. Limited-substrate assays in which re-initiation of RNA chains did not occur also showed that captan had no effect on the elongation reaction. Studies which measured the interaction of RNA polymerase with template DNA revealed that the binding of enzyme to DNA was inhibited by captan. Glycerol-gradient sedimentation of the captan-treated RNA polymerase indicated that the inhibition of the enzyme was irreversible and did not result in dissociation of its subunits. These data are consistent with a mechanism in which RNA polymerase activity was irreversibly altered by captan, resulting in an inability of the enzyme to bind to the template. This interaction was probably at the DNA-binding site on the polymerase and did not involve reaction of captan with the DNA template.

Inhibition of RNA polymerase from Bacillus thuringiensis and Escherichia coli by β-exotoxin

1978 ◽  
Vol 24 (5) ◽  
pp. 537-543 ◽  
Author(s):  
Donovan E. Johnson
Keyword(s):  
Escherichia Coli ◽  
Bacillus Thuringiensis ◽  
Rna Polymerase ◽  
Polymerase Activity ◽  
Growth Stages ◽  
E Coli ◽  
Synthetic Dna ◽  
Rna Polymerase Activity ◽  
Normal Sensitivity ◽  
Dna Template

The characteristics of exotoxin inhibition of deoxyribonucleic acid (DNA) dependent ribonucleic acid (RNA) polymerase isolated from Escherichia coli and Bacillus thuringiensis were investigated. RNA polymerase isolated from a variety of growth stages was partially purified and assayed using several different native and synthetic DNA templates, and exotoxin inhibition patterns were recorded for each. Although 8 to 20-h RNA polymerase extracts of E. coli retained normal sensitivity to exotoxin (50% inhibition at a concentration of 7.5 × 10−6 M exotoxin), RNA polymerase isolated from late exponential and ensuing stationary-phase cultures of B. thuringiensis were nearly 50% less sensitive than exponential RNA polymerase activity. Inhibition patterns relating culture age at the time of RNA polymerase extraction to exotoxin inhibition suggested a direct correlation between diminishing exotoxin sensitivity and sporulation. Escherichia coli RNA polymerase could be made to mimic the B. thuringiensis exotoxin inhibition pattern by removal of sigma from the holoenzyme. After passage through phosphocellulose, exotoxin inhibition of the core polymerase was 30% less than the corresponding inhibition of E. coli holoenzyme. Heterologous enzyme reconstruction and assay were not possible due to loss of activity from the B. thuringiensis preparation during phosphocellulose chromatography, apparently from the removal of magnesium. In enzyme velocity studies, inhibition with exotoxin was noncompetitive with respect to the DNA template in the RNA polymerase reaction.

scholarly journals Effect of Phenylhydrazine-induced Hemolytic Anemia on Nuclear RNA Polymerase Activity of the Mouse Spleen

Blood ◽  
1973 ◽  
Vol 42 (2) ◽  
pp. 257-266 ◽  
Author(s):  
Jerry L. Spivak ◽  
Dennis Toretti ◽  
Herbert W. Dickerman
Keyword(s):  
Ionic Strength ◽  
Rna Polymerase ◽  
Hemolytic Anemia ◽  
Nuclear Dna ◽  
Polymerase Activity ◽  
Tenfold Increase ◽  
Rna Polymerase Activity ◽  
Low Ionic Strength ◽  
Dna Template ◽  
Nuclear Rna Polymerase

Abstract The DNA-dependent RNA polymerase of nuclei from lymphoid-rich and erythroid-rich mouse spleens was compared in regard to requirements and conditions of the reactions. The inhibition by either actinomycin D or pancreatic DNase indicated that a DNA template was required for the observed reactions. Following the induction of a hemolytic anemia by the administration of phenylhydrazine, there was a tenfold increase in the nuclear polymerase activity per milligram nuclear DNA of the developing erythropoietic spleen when the assays were done at low ionic strength and more than a threefold increase at high ionic strength. The peak rise in polymerase activity precedes the maximal development of the erythropoietic spleen by 3 days.

Pharmaceutical interference of the EWS-FLI1-driven transcriptome by co-targeting H3K27ac and RNA polymerase activity in Ewing Sarcoma

2021 ◽  
pp. molcanther.MCT-20-0489-A.2020
Author(s):  
Daniel A. R. Heisey ◽  
Sheeba Jacob ◽  
Timonthy L Lochmann ◽  
Richard Kurupi ◽  
Maninderjit S. Ghotra ◽  
...  
Keyword(s):  
Rna Polymerase ◽  
Ewing Sarcoma ◽  
Polymerase Activity ◽  
Rna Polymerase Activity

RNA polymerase activity in virions from Ustilago maydis

1984 ◽  
Vol 4 (1) ◽  
pp. 188-194
Author(s):  
B S Ben-Tzvi ◽  
Y Koltin ◽  
M Mevarech ◽  
A Tamarkin
Keyword(s):  
Rna Polymerase ◽  
Viral Genome ◽  
Ustilago Maydis ◽  
Polymerase Activity ◽  
Reaction Products ◽  
Double Stranded Rna ◽  
Rna Molecules ◽  
Rna Transcripts ◽  
Rna Polymerase Activity

RNA polymerase activity is associated with the double-stranded RNA virions of Ustilago maydis. The reaction products of the polymerase activity are single-stranded RNA molecules. The RNA molecules synthesized are homologous to the three classes of double-stranded RNA molecules that typify the viral genome. The single-stranded RNA synthesized is released from the virions. The molecular weight of the single-stranded RNA transcripts is about half the size of the double-stranded RNA segments, and thus, it appears that in the in vitro reaction, full-length transcripts can be obtained.

scholarly journals HDAC6 Restricts Influenza A Virus by Deacetylation of the RNA Polymerase PA Subunit

2018 ◽  
Vol 93 (4) ◽  
Author(s):  
Huan Chen ◽  
Yingjuan Qian ◽  
Xin Chen ◽  
Zhiyang Ruan ◽  
Yuetian Ye ◽  
...  
Keyword(s):  
Life Cycle ◽  
Rna Polymerase ◽  
Influenza A Virus ◽  
Influenza A ◽  
Molecular Mechanisms ◽  
Polymerase Activity ◽  
Negative Regulator ◽  
Host Protein ◽  
Spectrometric Analysis ◽  
Rna Polymerase Activity

ABSTRACT The life cycle of influenza A virus (IAV) is modulated by various cellular host factors. Although previous studies indicated that IAV infection is controlled by HDAC6, the deacetylase involved in the regulation of PA remained unknown. Here, we demonstrate that HDAC6 acts as a negative regulator of IAV infection by destabilizing PA. HDAC6 binds to and deacetylates PA, thereby promoting the proteasomal degradation of PA. Based on mass spectrometric analysis, Lys(664) of PA can be deacetylated by HDAC6, and the residue is crucial for PA protein stability. The deacetylase activity of HDAC6 is required for anti-IAV activity, because IAV infection was enhanced due to elevated IAV RNA polymerase activity upon HDAC6 depletion and an HDAC6 deacetylase dead mutant (HDAC6-DM; H216A, H611A). Finally, we also demonstrate that overexpression of HDAC6 suppresses IAV RNA polymerase activity, but HDAC6-DM does not. Taken together, our findings provide initial evidence that HDAC6 plays a negative role in IAV RNA polymerase activity by deacetylating PA and thus restricts IAV RNA transcription and replication. IMPORTANCE Influenza A virus (IAV) continues to threaten global public health due to drug resistance and the emergence of frequently mutated strains. Thus, it is critical to find new strategies to control IAV infection. Here, we discover one host protein, HDAC6, that can inhibit viral RNA polymerase activity by deacetylating PA and thus suppresses virus RNA replication and transcription. Previously, it was reported that IAV can utilize the HDAC6-dependent aggresome formation mechanism to promote virus uncoating, but HDAC6-mediated deacetylation of α-tubulin inhibits viral protein trafficking at late stages of the virus life cycle. These findings together will contribute to a better understanding of the role of HDAC6 in regulating IAV infection. Understanding the molecular mechanisms of HDAC6 at various periods of viral infection may illuminate novel strategies for developing antiviral drugs.

RNA polymerase activity in germinating onion seeds

1972 ◽  
Vol 11 (11) ◽  
pp. 3105-3110 ◽  
Author(s):  
J.F. Payne ◽  
Arya K. Bal
Keyword(s):  
Rna Polymerase ◽  
Polymerase Activity ◽  
Rna Polymerase Activity
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