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 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 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 Species-specific rDNA transcription is due to promoter-specific binding factors.

1984 ◽  
Vol 4 (2) ◽  
pp. 221-227 ◽  
Author(s):  
R Miesfeld ◽  
N Arnheim
Keyword(s):  
Rna Polymerase ◽  
Transcriptional Control ◽  
Specific Binding ◽  
Rna Polymerase I ◽  
Rdna Transcription ◽  
Nucleolar Dominance ◽  
Cell Extracts ◽  
Species Specific ◽  
Polymerase I

RNA polymerase I transcription factors were purified from HeLa and mouse L cell extracts by phosphocellulose chromatography. Three fractions from each species were found to be required for transcription. One of these fractions, virtually devoid of RNA polymerase I activity, was found to form a stable preinitiation complex with small DNA fragments containing promoter sequences from the homologous but not the heterologous species. These species-specific DNA-binding factors can explain nucleolar dominance in vivo in mouse-human hybrid somatic cells and species specificity in cell-free, RNA polymerase I-dependent transcription systems. The evolution of species-specific transcriptional control signals may be the natural outcome of a special relationship that exists between the RNA polymerase I transcription machinery and the multigene family coding for rRNA.

scholarly journals Stimulation of the mouse rRNA gene promoter by a distal spacer promoter.

1995 ◽  
Vol 15 (8) ◽  
pp. 4648-4656 ◽  
Author(s):  
M H Paalman ◽  
S L Henderson ◽  
B Sollner-Webb
Keyword(s):  
Rna Polymerase ◽  
Gene Promoter ◽  
Rna Polymerase I ◽  
Rrna Gene ◽  
Transcriptional Terminator ◽  
Wide Range ◽  
Polymerase I ◽  
Enhancer Sequences ◽  
Stimulation Of

We show that the mouse ribosomal DNA (rDNA) spacer promoter acts in vivo to stimulate transcription from a downstream rRNA gene promoter. This augmentation of mammalian RNA polymerase I transcription is observed in transient-transfection experiments with three different rodent cell lines, under noncompetitive as well as competitive transcription conditions, over a wide range of template concentrations, whether or not the enhancer repeats alone stimulate or repress expression from the downstream gene promoter. Stimulation of gene promoter transcription by the spacer promoter requires the rDNA enhancer sequences to be present between the spacer promoter and gene promoter and to be oriented as in native rDNA. Stimulation also requires that the spacer promoter be oriented toward the enhancer and gene promoter. However, stimulation does not correlate with transcription from the spacer promoter because the level of stimulation is not altered by either insertion of a functional mouse RNA polymerase I transcriptional terminator between the spacer promoter and enhancer or replacement with a much more active heterologous polymerase I promoter. Further analysis with a series of mutated spacer promoters indicates that the stimulatory activity does not reside in the major promoter domains but requires the central region of the promoter that has been correlated with enhancer responsiveness in vivo.

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 Novel Assay to Detect RNA Polymerase I Activity In Vivo

2017 ◽  
Vol 15 (5) ◽  
pp. 577-584 ◽  
Author(s):  
Gunes Guner ◽  
Paul Sirajuddin ◽  
Qizhi Zheng ◽  
Baoyan Bai ◽  
Alexandra Brodie ◽  
...  
Keyword(s):  
Rna Polymerase ◽  
Rna Polymerase I ◽  
Polymerase I

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 In vivo evidence that TATA-binding protein/SL1 colocalizes with UBF and RNA polymerase I when rRNA synthesis is either active or inactive.

1996 ◽  
Vol 133 (2) ◽  
pp. 225-234 ◽  
Author(s):  
P Jordan ◽  
M Mannervik ◽  
L Tora ◽  
M Carmo-Fonseca
Keyword(s):  
Rna Polymerase ◽  
Actinomycin D ◽  
Binding Protein ◽  
Tata Binding Protein ◽  
Rna Polymerase I ◽  
Rrna Genes ◽  
Rrna Synthesis ◽  
Rrna Transcription ◽  
Polymerase I

Here we show that the TATA-binding protein (TBP) is localized in the nucleoplasm and in the nucleolus of mammalian cells, consistent with its known involvement in transcription by RNA polymerase I, II, and III. In the nucleolus of actively growing cells, TBP colocalizes with upstream binding factor (UBF) and RNA polymerase I at the sites of rRNA transcription. During mitosis, when rRNA synthesis is down-regulated, TBP colocalizes with TBP-associated factors for RNA polymerase I (TAF(I)s), UBF, and RNA polymerase I on the chromosomal regions containing the rRNA genes. Treatment of cells with a low concentration of actinomycin D inhibits rRNA synthesis and causes a redistribution of the rRNA genes that become concentrated in clusters at the periphery of the nucleolus. A similar redistribution was observed for the major components of the rRNA transcription machinery (i.e., TBP, TAF(I)s, UBF, and RNA polymerase I), which still colocalized with each other. Furthermore, anti-TBP antibodies are shown to coimmunoprecipitate TBP and TAF(I)63 in extracts prepared from untreated and actinomycin D-treated cells. Collectively, the data indicate that in vivo TBP/promoter selectivity factor, UBF, and RNA polymerase I remain associated with both active and inactive rRNA genes.

Sign in / Sign up

Export Citation Format

Share Document