Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P06889 (Mol)
 630,302 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Progesterone causes in goblet cells of oviducts of estrogen hormone-stimulated immature quails selectively gene activation without affecting DNA synthesis. This biological model has been used to study the influence of poly ADP-ribosylation during the processes of DNA transcription. Administration of progesterone in vivo causes an increase of the activity of RNA polymerase I and II in isolated nuclei. This increase is accompanied by a marked decrease of the specific activity of poly (ADP-Rib) polymerase. After in vitro ADP-ribosylation of nuclear proteins the template capacity of chromatin for ""exogenous'' RNA synthesis (with E. coli DNA-dependent RNA polymerases) as well as for ""endogenous'' RNA synthesis with DNA dependent RNA polymerases II is not affected, whereas the data presented seem to indicate that the capacity for RNA synthesis mediated by ""endogenous'' DNA-dependent RNA polymerase I might be inhibited after ADP-ribosylation. Evidence is presented to show that a considerable amount of poly (ADP-Rib), synthesized by poly (ADP-Rib) polymerase in isolated nuclei, is linked with RNA polymerase I. The rate of synthesis of poly (ADP-Rib) is dependent on the incubation temperature (optimum at 25 degrees C) and it can be inhibited by the specific inhibitors of poly (ADP-Rib) polymerase nicotineamide, thymidine and formycin B. Poly (ADP-Rib) is probably associated with RNA polymerase I through a covalent linkage. ADP-ribosylated RNA polymerase I has been purified 550 fold with respect to the nuclear extract corresponding to a 4,000 fold purification from the whole cell homogenate. The ratio between poly (ADP-Rib), formed during preincubation of nuclei with NAD, and RNA polymerase I remains almost constant during the purification procedures. The extent of ADP-ribosylation of RNA polymerase I decreases during gene expression. Thus we conclude that poly ADP-ribosylation of this enzyme is one of the regulatory mechanisms by which specificity of DNA transcription is achieved.
Mol Cell Biochem 1976 Sep 30
PMID:Poly ADP-ribosylation of DNA-dependent RNA polymerase I from quail oviduct. Dependence on progesterone stimulation. 18 9

An attempt was made to elucidate possible participation of low molecular weight nuclear RNA's (LMWN RNA's) in the transcription process. For this purpose, we studied the effect of individual fractions of LMWN RNA's, isolated by polyacrylamide gel electrophoresis, on the endogenous RNA synthesis in isolated nuclei. We have found no influence of LMWN RNA's on the incorporation of labeled precursors in the acid-insoluble material under the conditions when RNA polymerase I is predominantly active. The results obtained thus indicate that LMWN RNA's do not participate in the regulation of 45S pre-rRNA synthesis and they do not belong to limiting factors in pre-rRNA synthesis.
Mol Biol (Mosk)
PMID:[Effect of low-molecular nuclear RNA on RNA synthesis in isolated nuclei]. 20 64

A structural gene for sigma factor (rpoD) of DNA-dependent RNA polymerase (RNA nucleotidyltransferase; nucleoside-triphosphate: RNA nucleotidyltransferase, E.C. 2.7.7.6) was mapped precisely by a set of F' factors including those already published (Proc. Natl. Acad. Sci. USA. 74, 1831-1835 (1977)). Based on the result that rpoD is located at the dnaG-uxaAC region, a number of mutants containing a temperature-sensitive mutation at or near the uxaA gene were isolated by localized mutagenesis. One of these mutants was found to produce RNA polymerase altered in both thermostability and optimum salt concentration as a result of structural alteration of sigma factor. This mutation, U303, maps at 66 min on the genetic map of E. coli, near the dnaG locus, and affects normal growth of cells.
Mol Gen Genet 1978 Sep 20
PMID:RNA polymerase mutant with altered sigma factor in Escherichia coli. 36 59

We studied the rate of synthesis of beta-and beta'-subunits of DNA-dependent RNA polymerase and the rate of beta-polypeptide mRNA synthesis in rifampicin-treated bacteria. The chosen antibiotic doses did not significantly inhibit the total RNA and protein synthesis in rifampicin-sensitive bacteria. For RNA-DNA hybridization experiments a pOD162 plasmid was constructed carrying a fragment of the rpoB gene and no other chromosome DNA regions. It was found that low doses of rifampicin cause an absolute and a relative increase in the rate of synthesis of the specific mRNA for the beta-subunit, suggesting a stimulation of the corresponding gene transcription and excluding the possibility of a less pronounced inhibition of the rpoB gene expression compared to that of most other genes. However the relative acceleration of transcription is substantially higher than the absolute one. The stimulating effect of rifampicin on the beta-polypeptide synthesis is also demonstrated in a coupled system of transcription and translation directed by lambda rifd47 DNA. The possible mechanisms of the rifampicin action are discussed.
Mol Gen Genet 1979 May 23
PMID:The effect of rifampicin upon the transcription of RNA polymerase beta-gene in Escherichia coli. 38 37

The interaction of pyridoxal, pyridoxal-5'-mono-, di- and triphosphate with certain enzymes of polynucleotide synthesis (DNA-dependent RNA polymerase, DNA-dependent DNA polymerase I and polynucleotide phosphorylase from Escherichia coli and terminal deoxyribonucleotide transferase from calf thymus) was studied. All compounds tested was found to be reversible and competitive inhibitors of these enzymes. The reduction of the enzyme-inhibitor complex with NaBH4 gives rise to the complete irreversible inhibition of the enzymes under study. The comparison of the inhibition constants for pyridoxal and its phosphorylated derivatives with those for mono-, di- and triphosphates of nucleosides was carried out for the enzymes. The results obtained suggest that the modified epsilon-amino-group of lysine residue should be localized at the catalytic site in the vicinity of the pyrophosphate binding area of an enzyme.
Mol Biol (Mosk)
PMID:[Interaction of oligophosphates of pyridoxal with certain enzymes of polynucleotide synthesis]. 38 98

Two hundred strains of Saccharomyces cerevisiae temperature sensitive for RNA synthesis were selected and screened in crude extracts for DNA-dependent RNA polymerase activities. One strain was isolated which had only residual in vitro RNA polymerase B activity. In normal growth conditions total RNA, poly A+ RNA and protein synthesis were indistinguishable from those of the wild type strain at 23 degrees C and after shift to 37 degrees C. A temperature sensitive phenotype was detected only when rpoB containing strains were grown in adverse conditions. The mutant character showed mendelian segregation and was coexpressed with the wild type character in heterozygous diploids. Residual enzyme activity was characterised in crude extracts using synthetic polymers and natural templates in different ionic conditions.
Mol Gen Genet 1979 Jun 07
PMID:Isolation and characterisation of a strain of Saccharomyces cerevisiae deficient in in vitro RNA polymerase B(II) activity. 38 33

We studied the rate of synthesis of beta- and beta'-subunits of DNA-dependent RNA polymerase and the rate of beta-polypeptide mRNA synthesis in rifampicin-treated bacteria. The antibiotic doses used did not significantly inhibit the total RNA and protein synthesis in rifampicin-sensitive bacteria. For RNA-DNA hybridization experiments a pOD162 plasmid was constructed carrying a fragment of the rpoB gene and no other chromosome DNA regions. It is found that low doses of rifampicin cause an absolute and differential increase in the rate of synthesis of the specific mRNA for the beta-subunit, suggesting a stimulation of the corresponding gene transcription. However the absolute transcription stimulation does not fully correlate with the relative acceleration of beta-mRNA and the corresponding polypeptide synthesis. The stimulating effect of rifampicin on the beta-polypeptide synthesis was demonstrated also in a coupled system of transcription and translation directed by lambda rifd 47 DNA. The possible mechanisms of the rifampicin action are discussed.
Mol Biol (Mosk)
PMID:[Effect of rifampicin on the synthesis of bacterial RNA polymerase mRNA by means of hybrid plasmids]. 38 90

DNA-dependent RNA polymerase has been found to be preferentially released at 43 degrees C from the folded nucleoids of an E. coli dnaAts mutant when compared with the same nucleoids at 30 degrees C or with nucleoids of a dnaA+ strain at either 30 degrees or 43 degrees C. The polypeptides released are identical in molecular weight with those of the beta and beta' constituent polypeptides of the core enzyme of a known E. coli RNA polymerase. In addition, these polypeptides are precipitated by specific anti-RNA polymerase rabbit IgG. The implications of the interactions of RNA polymerase with the dnaA gene product are discussed.
Mol Gen Genet 1979 Sep
PMID:Temperature dependent release of beta-beta' subunits of DNA dependent RNA polymerase from the folded chromosome of a dnaAts mutant of Escherichia coli. 39 Mar 10

Synthesis of malic enzyme was rapidly and markedly stimulated by the addition of triiodothyronine to chick embryo liver cells in culture. Alpha-Amanitin, an inhibitor of DNA-dependent RNA polymerase II, blocked induction. The kinetics of induction and de-induction of malic enzyme synthesis suggested that the most stable event in triiodothyronine induction had a half-life of 18 to 20 h. However, malic enzyme synthesis decayed with a half-life of 2,4 h when transcription was inhibited with alpha-amanitin. Thus a long-lived event in thyroid hormone stimulation of malic enzyme synthesis occurred prior to transcription of a specific messenger RNA (mRNA), presumably malic enzyme mRNA. Malic enzyme synthesis decayed with a half-life of about 2 h when glucagon was added to pre-induced liver cells. The similarity of decay rates after inhibition of transcription with alpha-amanitin or inhibition of malic enzyme synthesis by glucagon suggests that glucagon may inhibit the transcription or processing of a specific mRNA required for malic enzyme synthesis.
Mol Cell Endocrinol 1978 Jun
PMID:Regulation of malic enzyme synthesis by thyroid hormone and glucagon: inhibitor and kinetic experiments. 56 41

As an effort to elucidate the control of quality and quantity of the DNA-dependent RNA polymerase in Escherichia coli, the rate of synthesis of the individual subunits was determined during shift-up and -down of nutrients. When the strain B/r grown in a succinate medium was imposed to a shift-up by adding a mixture of glucose and amino acids, rapid rise was observed of the differential rates of the synthesis of alpha, beta and beta' subunits, the constituents of core enzyme, leading to the increase of core polymerase concentration. The differential rates decreased thereafter to the level characteristic of the post-shift rate of cell growth. Compared to the strain B/r, the adaptation was slow in the strain K12 W3350. On the other hand, upon transfer of the strain B/r from a glucose-amino acids medium to a glucose medium lacking amino acids, the differential rate of core polymerase synthesis decreased rapidly and then regained the rate characteristic of the new growth rate. Similar control was also observed on the rate of ribosomal protein synthesis suggesting the coordinate expression of genes for the core polymerase subunits and ribosomal proteins. Thus, the intracellular concentration of RNA polymerase as well as of ribosomes might be one of the most important factors that affect the rate of bacterial growth. The rate of alpha subunit synthesis, however, exhibited little change during the shift-up but a considerable decrease was observed during the shift-down.
Mol Gen Genet 1975 Dec 23
PMID:Biosynthesis of RNA polymerase in Escherichia coli. II. control of RNA polymerase synthesis during nutritional shift up and down. 76 37


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