scholarly journals Estrogen-induced modification of uterine RNA polymerase activity depends on localization of the estrogen receptor

2007 ◽  
Vol 59 (2) ◽  
pp. 105-112
Author(s):  
Zorica Zakula ◽  
Esma Isenovic ◽  
Mojca Stojiljkovic ◽  
G. Koricanac ◽  
Snezana Tepavcevic ◽  
...  
Keyword(s):  
Estrogen Receptor ◽  
Rna Polymerase ◽  
Rna Polymerase Ii ◽  
Polymerase Activity ◽  
Rna Polymerase I ◽  
Female Rats ◽  
Cytosol Fraction ◽  
Ovx Rats ◽  
Rna Polymerase Activity ◽  
Polymerase I

The aim of this study was to examine the effects of estradiol (E2) on activity of RNA polymerase I and RNA polymerase II in uterine nuclei of ovariectomized (OVX) female rats. The obtained results show that estrogen-receptor (E-R) complexes in 30 min induced an increase of polymerase II activity. A second increase of polymerase II activity was observed after 3 h-incubation of nuclei with the E-R complex formed in the cytosol fraction. However, activity of polymerase I was increased 2 h after the start of incubation, with highest activity detected at 3 h in nuclei incubated with E-R complexes. On the contrary, no stimulatory effect on either polymerase I or polymerase II activity was observed in nuclei incubated with E2 alone. These results indicate that E2 stimulates the cytosolic estrogen receptor (ER), which in turn causes uterotrophic responses in OVX rats. In addition, they suggest that in order to provoke uterotrophic responses E-R complexes formed in the cytosol need to be retained in the nucleus for a longer period of time. .

scholarly journals Nuclear binding of progesterone in chick oviduct. Multiple binding sites in vivo and transcriptional response

1976 ◽  
Vol 156 (2) ◽  
pp. 391-398 ◽  
Author(s):  
T C Spelsberg
Keyword(s):  
Rna Polymerase ◽  
Rna Polymerase Ii ◽  
Binding Sites ◽  
Polymerase Activity ◽  
Rna Polymerase I ◽  
Target Tissue ◽  
Functional Sites ◽  
Nuclear Binding ◽  
Polymerase I

1. Varied doses of labelled or unlabelled progesterone were injected into immature chicks which had previously been stimulated with oestrogen. The concentrations of nuclear bound [3H]progesterone were correlated with the effects of the hormone on endogenous RNA polymerase I and II activities in isolated oviduct nuclei. 2. The extent of nuclear localization of [3H]progesterone in oviduct (a progesterone target tissue) was shown to be much greater than in lung (non-target tissue). The conccentration of bivalent cations in solvents used in the nuclei isolations has a marked effect on the amount of bound hormone in the nuclei. 3. Evidence for the existence of several classes of binding sites for progesterone in the oviduct nuclei is given. These classes represent about 1000) 10000 and 100000 molecules of the hormone per cell nucleus and are saturated by injecting approx. 10, 100 and 1000 mug of progesterone respectively. 4. When saturation of the first (highest affinity) class of nuclear sites occurs, a marked inhibition in RNA polymerase II (but not RNA polymerase I) activity was observed. When the second class of sites was saturated, alterations in both RNA polymerase I and II activities were observed. Binding to the third class of nuclear binding sites was not accompained by further changes in polymerase activity. It is suggested that the first two classes of nuclear binding sites may represent functional sites for progesterone action in the chick oviduct.

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.

Activity of purified and chromatin-associated mouse TLT hepatoma RNA polymerases on homologous whole chromatin and euchromatin-enriched segments isolated from homologous chromatin

1977 ◽  
Vol 55 (3) ◽  
pp. 227-238 ◽  
Author(s):  
Ralph J. Smith ◽  
Jacob D. Duerksen
Keyword(s):  
Rna Polymerase ◽  
Gradient Centrifugation ◽  
Distribution Patterns ◽  
Polymerase Activity ◽  
Rna Polymerase I ◽  
Glycerol Gradient ◽  
Rna Polymerase Activity ◽  
Gradient Fractionation ◽  
Polymerase I ◽  
Diffuse Distribution

The RNA polymerase (EC 2.7.7.6) activity of mouse TLT hepatoma nuclei is separable into three forms, I, IIA, and IIB; each of these partially purified enzymes demonstrates characteristics generally similar to those reported for these enzymes of other systems. All three forms of TLT hepatoma RNA polymerase show a considerable preference for single-stranded DNA. The full expression of the endogenous RNA polymerase activity of mouse TLT hepatoma chromatin is dependent on the salt concentration. No additional template activity to added RNA polymerase I or II is available. Physical shearing decreased endogenous RNA polymerase activity and increased template capacity to the added enzymes. Glycerol-gradient fractionation of physically sheared chromatin gave a fairly diffuse distribution of the endogenous RNA polymerase activity to the marginally euchromatin-enriched fractions. However, enzymatic shearing of TLT hepatoma chromatin by Mg,Ca-dependent autodigestion results in a distribution of endogenous RNA polymerase activity to the highly euchromatin-enriched fractions similar to that obtained for nascent RNA (Paul, I. J. &Duerksen, J. D. (1976) Biochem. Biophys. Res. Commun. 68, 97–105). The distribution patterns of template capacity determined with added RNA polymerase I and II differed somewhat from the above distributions and varied with the length of autodigestion. Shearing by autodigestion is preferred, and followed by glycerol-gradient centrifugation permits a considerable enrichment for euchromatic segments.

scholarly journals Feedback regulation of vitamin D metabolism by 1,25-dihydroxycholecalciferol

1977 ◽  
Vol 164 (1) ◽  
pp. 83-89 ◽  
Author(s):  
K W Colston ◽  
I M A Evans ◽  
T C Spelsberg ◽  
I MacIntyre
Keyword(s):  
Vitamin D ◽  
Rna Polymerase ◽  
Rna Polymerase Ii ◽  
Gene Transcription ◽  
Subcutaneous Administration ◽  
Feedback Regulation ◽  
Rna Polymerase I ◽  
Hydroxylase Activity ◽  
Vitamin D Metabolism ◽  
Polymerase I

Many factors influence the production of 1,25(OH)2D3 (1,25-dihydroxycholecalciferol) by the kidney. One important factor seems to be feedback regulation by 1,25(OH)2D3 itself. Administration of 1,25(OH)2D3 to vitamin D-deficient chicks abolishes renal 25(OH)D3(25-hydroxycholecalciferol)1-hydroxylase activity and induces the appearance of 25(OH)D3 24-hydroxylase activity. It is likely that these effects are mediated via a nuclear effect, as they are prevented by pretreatment with actinomycin D and alpha-amanitin. Further, 1,25(OH)2D3 has a marked effect on gene transcription in the kidney cell, as assessed by measurement of RNA polymerase activities. RNA polymerase I and II activities are 80-90% inhibited by 12.5nmol of 1,25(OH)2D3 within 30min of subcutaneous administration, indicating an immediate and massive decrease in total gene transcription. By 4h RNA polymerase II activity has returned to control values, but RNA polymerase I activity is markedly enhanced. These results are consistent with the view that regulation of cholecalciferol metabolism in the kidney is associated with an effect of the active metabolite on the kidney nucleus.

scholarly journals Assembly and Functional Organization of the Nucleolus: Ultrastructural Analysis ofSaccharomyces cerevisiaeMutants

2000 ◽  
Vol 11 (6) ◽  
pp. 2175-2189 ◽  
Author(s):  
Stéphanie Trumtel ◽  
Isabelle Léger-Silvestre ◽  
Pierre-Emmanuel Gleizes ◽  
Frédéric Teulières ◽  
Nicole Gas
Keyword(s):  
Rna Polymerase ◽  
Rna Polymerase Ii ◽  
Functional Organization ◽  
Ultrastructural Localization ◽  
Rna Polymerase I ◽  
Wild Type ◽  
Rdna Transcription ◽  
Nucleolar Structure ◽  
Fibrillar Component ◽  
Polymerase I

Using Saccharomyces cerevisiae strains with genetically modified nucleoli, we show here that changing parameters as critical as the tandem organization of the ribosomal genes and the polymerase transcribing rDNA, although profoundly modifying the position and the shape of the nucleolus, only partially alter its functional subcompartmentation. High-resolution morphology achieved by cryofixation, together with ultrastructural localization of nucleolar proteins and rRNA, reveals that the nucleolar structure, arising upon transcription of rDNA from plasmids by RNA polymerase I, is still divided in functional subcompartments like the wild-type nucleolus. rRNA maturation is restricted to a fibrillar component, reminiscent of the dense fibrillar component in wild-type cells; a granular component is also present, whereas no fibrillar center can be distinguished, which directly links this latter substructure to rDNA chromosomal organization. Although morphologically different, the mininucleoli observed in cells transcribing rDNA with RNA polymerase II also contain a fibrillar subregion of analogous function, in addition to a dense core of unknown nature. Upon repression of rDNA transcription in this strain or in an RNA polymerase I thermosensitive mutant, the nucleolar structure falls apart (in a reversible manner), and nucleolar constituents partially relocate to the nucleoplasm, indicating that rRNA is a primary determinant for the assembly of the nucleolus.

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 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.

scholarly journals Nucleolar TFIIE plays a role in ribosomal biogenesis and performance

2020 ◽  
Author(s):  
Tamara Phan ◽  
Pallab Maity ◽  
Christina Ludwig ◽  
Lisa Streit ◽  
Jens Michaelis ◽  
...  
Keyword(s):  
Rna Polymerase ◽  
Rna Polymerase Ii ◽  
Ribosome Biogenesis ◽  
Initiation Site ◽  
Rna Polymerase I ◽  
Ribosomal Biogenesis ◽  
Protein Coding ◽  
Degenerative Disorder ◽  
And Performance ◽  
Polymerase I

Ribosome biogenesis is a highly energy-demanding process in eukaryotes which requires the concerted action of all three RNA polymerases. In RNA polymerase II transcription, the general transcription factor TFIIH is recruited by TFIIE to the initiation site of protein-coding genes. Distinct mutations in TFIIH and TFIIE give rise to the degenerative disorder trichothiodystrophy (TTD). Here we uncovered an unexpected role of TFIIE in ribosomal RNA synthesis by RNA polymerase I. With high resolution microscopy we detected TFIIE in the nucleolus where TFIIE binds to actively transcribed rDNA. Mutations in TFIIE affects gene-occupancy of RNA polymerase I, rRNA maturation, ribosomal assembly and performance. In consequence, the elevated translational error rate with imbalanced protein synthesis and turnover results in an increase in heat-sensitive proteins. Collectively, mutations in TFIIE - due to impaired ribosomal biogenesis and translational accuracy - lead to a loss of protein homeostasis (proteostasis) which can partly explain the clinical phenotype in TTD.

Human ribosomal DNA fragments amplified in hamster cells are transcribed only by RNA polymerase II and are not silver stained

1987 ◽  
Vol 7 (3) ◽  
pp. 1289-1292
Author(s):  
V N Dhar ◽  
D A Miller ◽  
A B Kulkarni ◽  
O J Miller
Keyword(s):  
Rna Polymerase ◽  
Rna Polymerase Ii ◽  
Ribosomal Dna ◽  
Chinese Hamster ◽  
Rna Polymerase I ◽  
Rrna Gene ◽  
Methotrexate Resistance ◽  
Selection For ◽  
Polymerase I ◽  
Chromosome Regions

Cloned human rRNA gene fragments that included the promoter region were introduced into Chinese hamster dihydrofolate reductase-deficient (dhfr-) cells by cotransformation with a dhfr minigene and amplified by selection for methotrexate resistance. The human ribosomal DNA was transcribed by RNA polymerase II, not RNA polymerase I or III. The metaphase chromosome regions containing the transcriptionally active human ribosomal DNA failed to show silver staining.

scholarly journals Deoxyribonucleic acid-dependent ribonucleic acid polymerase activity in rat liver after protein restriction

1975 ◽  
Vol 148 (1) ◽  
pp. 49-56 ◽  
Author(s):  
G M Andersson ◽  
A von der Decken
Keyword(s):  
Rna Polymerase ◽  
Dietary Protein ◽  
Deoxyribonucleic Acid ◽  
Specific Activity ◽  
Polymerase Activity ◽  
Rna Polymerase I ◽  
High Quality ◽  
Sephadex Column ◽  
High Quality Protein ◽  
Polymerase I

Rats were fed for 6 days on a diet containing either 3 or 20% high-quality protein. Nuclei were isolated from liver and DNA-dependent RNA polymerases (EC 2.7.7.6) extracted with 1 M-(NH4)2SO4. The proteins were then precipitated with 3.5 M-(NH4)2SO4 and after dialysis applied to a DEAE-Sephadex column. The column was developed with a gradient of (NH4)2SO4. Polymerase I separated well from α-amanitin-sensitive polymerase II. The enzyme activities were compared between the two dietary groups. Rats that had received 3% protein showed a lower polymerase I activity per g wet wt. of liver, per mg of DNA and per mg of protein. Polymerase II was lower in activity per g wet wt. of liver and per mg of DNA, but was higher per mg of protein. Polyacrylamide-gel electrophoretograms showed a higher proportion of contaminating proteins in polymerase II fractions isolated from 20%-protein-fed rats. The data explain the lower activity obtained per mg of protein in these rats. It is concluded that a decrease in dietary protein content from 20 to 3% induces a fall in content and specific activity of RNA polymerase I and II in liver.

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