Evidence for the transcription of physiologically inactive rat-liver nucleolar chromatin by Escherichia coli RNA polymerase

1982 ◽  
Vol 2 (3) ◽  
pp. 155-161 ◽  
Author(s):  
Fu-Li Yu ◽  
Annabella Barrett
Keyword(s):  
Escherichia Coli ◽  
Rna Polymerase ◽  
Rat Liver ◽  
Dnase I ◽  
Rna Polymerase I ◽  
E Coli ◽  
Chromatin Template ◽  
Nucleolar Chromatin ◽  
Polymerase I ◽  
Active Genes

Rat-liver nucleoli (10–15 pg DNA) were digested with either 0.6 or 3 units of DNase I for various times (up to 1 h). RNA synthesis was then measured in the absence or presence ol 3 units of Escherichia coli RNA polymerase. It was found that the nucleolar chromatin supporting the endogenous engaged RNA polymerase I transcription was compl-etely destroyed in 3 min with either concentration of DNase I. The nucleolar chromatin template transcribed by E. coli RNA polymerase retained 50% of its original capacity even 60 min alter 3 units of DNase I digestion. When hybridization experiments were conducted, it was found that the DNAs derived from both levels of DNase-Idigested nucleoli were incapable of forming hybrids with the labelled nucleolar RNA synthesized by the engaged RNA polymerase I from the untreated nucleoli. Since the engaged RNA polymerase I transcribes only the physiologically active genes of the nucleolar chromatin, and the RNA transcripts represent active gene product, these data suggest that DNase I digestion has completely destroyed the active genes of the nucleolar chromatin, and E. coli RNA polymerase is able to transcribe the inactive nucleolar chromatin template.

Alterations in DNA-dependent RNA polymerase I from rat liver accompanying ethionine administration

1982 ◽  
Vol 105 (3) ◽  
pp. 799-805 ◽  
Author(s):  
Haruko Yamano ◽  
Yasuko Sawai ◽  
Wen Long Thung ◽  
Fumiyasu Sato ◽  
Kinji Tsukada
Keyword(s):  
Rna Polymerase ◽  
Rat Liver ◽  
Rna Polymerase I ◽  
Polymerase I

Inactivation of rat liver RNA polymerases I and II and yeast RNA polymerase I by pyridoxal 5'-phosphate. Evidence for the participation of lysyl residues at the active site

Biochemistry ◽  
1975 ◽  
Vol 14 (22) ◽  
pp. 4907-4911 ◽  
Author(s):  
Joseph Martial ◽  
Josefina Zaldivar ◽  
Paulina Bull ◽  
Alejandro Venegas ◽  
Pablo Valenzuela
Keyword(s):  
Rna Polymerase ◽  
Rat Liver ◽  
Active Site ◽  
Rna Polymerases ◽  
Rna Polymerase I ◽  
Polymerase I

scholarly journals Nucleolin Is Required for RNA Polymerase I Transcription In Vivo

2006 ◽  
Vol 27 (3) ◽  
pp. 937-948 ◽  
Author(s):  
Brenden Rickards ◽  
S. J. Flint ◽  
Michael D. Cole ◽  
Gary LeRoy
Keyword(s):  
Rna Polymerase ◽  
Rna Polymerase Ii ◽  
Rna Polymerase I ◽  
Rrna Genes ◽  
Accessory Proteins ◽  
Naked Dna ◽  
Nucleolar Chromatin ◽  
Polymerase I

ABSTRACT Eukaryotic genomes are packaged with histones and accessory proteins in the form of chromatin. RNA polymerases and their accessory proteins are sufficient for transcription of naked DNA, but not of chromatin, templates in vitro. In this study, we purified and identified nucleolin as a protein that allows RNA polymerase II to transcribe nucleosomal templates in vitro. As immunofluorescence confirmed that nucleolin localizes primarily to nucleoli with RNA polymerase I, we demonstrated that nucleolin allows RNA polymerase I transcription of chromatin templates in vitro. The results of chromatin immunoprecipitation experiments established that nucleolin is associated with chromatin containing rRNA genes transcribed by RNA polymerase I but not with genes transcribed by RNA polymerase II or III. Knockdown of nucleolin by RNA interference resulted in specific inhibition of RNA polymerase I transcription. We therefore propose that an important function of nucleolin is to permit RNA polymerase I to transcribe nucleolar chromatin.

scholarly journals Tor Pathway Regulates Rrn3p-dependent Recruitment of Yeast RNA Polymerase I to the Promoter but Does Not Participate in Alteration of the Number of Active Genes

2004 ◽  
Vol 15 (2) ◽  
pp. 946-956 ◽  
Author(s):  
Jonathan A. Claypool ◽  
Sarah L. French ◽  
Katsuki Johzuka ◽  
Kristilyn Eliason ◽  
Loan Vu ◽  
...  
Keyword(s):  
Rna Polymerase ◽  
Stationary Phase ◽  
Rna Polymerase I ◽  
Rrna Synthesis ◽  
Synthesis Rate ◽  
Transcription Rate ◽  
Signaling System ◽  
Tor Signaling ◽  
Polymerase I ◽  
Active Genes

Yeast cells entering into stationary phase decrease rRNA synthesis rate by decreasing both the number of active genes and the transcription rate of individual active genes. Using chromatin immunoprecipitation assays, we found that the association of RNA polymerase I with the promoter and the coding region of rDNA is decreased in stationary phase, but association of transcription factor UAF with the promoter is unchanged. Similar changes were also observed when growing cells were treated with rapamycin, which is known to inhibit the Tor signaling system. Rapamycin treatment also caused a decrease in the amount of Rrn3p-polymerase I complex, similar to stationary phase. Because recruitment of Pol I to the rDNA promoter is Rrn3p-dependent as shown in this work, these data suggest that the decrease in the transcription rate of individual active genes in stationary phase is achieved by the Tor signaling system acting at the Rrn3p-dependent polymerase recruitment step. Miller chromatin spreads of cells treated with rapamycin and cells in post-log phase confirm this conclusion and demonstrate that the Tor system does not participate in alteration of the number of active genes observed for cells entering into stationary phase.

scholarly journals Effects of glucocorticoid and cycloheximide on the activity and amount of RNA polymerase I in nuclei of rat liver

1986 ◽  
Vol 235 (3) ◽  
pp. 699-705 ◽  
Author(s):  
H Matsui ◽  
H Yazawa ◽  
N Suzuki ◽  
T Hosoya
Keyword(s):  
Rna Polymerase ◽  
Rna Polymerase Ii ◽  
Rat Liver ◽  
Protein S ◽  
Rna Polymerase I ◽  
Free Form ◽  
Precursor Synthesis ◽  
Liver Nuclei ◽  
Polymerase I ◽  
Adrenalectomized Rats

The activity of the template-engaged form of RNA polymerase I from livers of adrenalectomized rats was about 50-60% of that of normal control rats, and increased about 2-fold at 6 h after the administration of dexamethasone. However, no change was found in the activity of the ‘free’ form of RNA polymerase I or the template-engaged form of RNA polymerase II. Immunochemical studies using guinea-pig anti-(RNA polymerase I) serum disclosed that the total number of RNA polymerase I molecules did not vary during the treatment with dexamethasone. Cycloheximide caused a rapid decrease in the template-engaged form of RNA polymerase I activity in normal rats and in dexamethasone-treated (6 h) adrenalectomized rats, to the value in adrenalectomized rats, but affected it only slightly in adrenalectomized rats. The elongation rate of rRNA-precursor synthesis in liver nuclei was not affected by a change in the concentration of circulating dexamethasone. From these results, it is concluded that about half the rRNA-precursor synthesis in rat liver is regulated by glucocorticoids, probably through the synthesis of short-lived protein(s) which may play a role in conversion of the ‘dormant’ form of RNA polymerase I into the ‘engaged’ form.

scholarly journals Changes in the number of binding sites for ribonucleic acid polymerase in chromatin of WI-38 fibroblasts stimulated to proliferate

1974 ◽  
Vol 141 (1) ◽  
pp. 27-34 ◽  
Author(s):  
Bridget T. Hill ◽  
Renato Baserga
Keyword(s):  
Escherichia Coli ◽  
Cell Division ◽  
Rna Polymerase ◽  
Ribonucleic Acid ◽  
Binding Sites ◽  
Template Activity ◽  
E Coli ◽  
Human Diploid Fibroblasts ◽  
Chromatin Template ◽  
Number Of Binding Sites

1. When WI-38 human diploid fibroblasts form confluent monolayers, DNA synthesis and cell division almost completely cease. A change of medium causes these density-inhibited cells to proliferate and within 1h after the application of the stimulus there is an increase in template activity of the chromatin isolated from stimulated cells. 2. The number of binding sites for Escherichia coli RNA polymerase was determined on chromatin from WI-38 cells by two different methods, i.e. incorporation of [3H]UTP into RNA in the absence of reinitiation, and incorporation of [γ-32P]GTP into chain termini. 3. Both methods indicate that the capacity of chromatin to bind E. coli RNA polymerase is increased in WI-38 cells stimulated to proliferate. 4. The increase in the number of binding sites for E. coli RNA polymerase parallels the increase in chromatin template activity and suggests that the latter reflects an increase in the number of initiation sites, rather than an increase in the rate of transcription.

Sign in / Sign up

Export Citation Format

Share Document