Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

---

Query: EC:2.7.7.6 (RNA polymerase)
34,946 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The procyclin genes of Trypanosoma brucei encode a family of glycoproteins expressed on the surface of procyclic forms of the parasite. These genes are present at different loci in tandem arrays of two or three copies depending on the strain. It has previously been shown that procyclin genes are transcribed from a promotor immediately upstream of the first procyclin gene in each cluster by an RNA polymerase that is resistant to high levels of alpha-amanitin. Here we show that additional genes, which we term procyclin-associated genes (PAGs), are located downstream of the procyclin genes and belong to the same alpha-amanitin-resistant polycistronic transcription units. A gene in the pro A locus, PAG 1, encodes a polypeptide that is related to the ESAG 6 and 7 proteins encoded in the VSG expression site. An unexpected feature of PAG 1 is that the major open reading frame of 405 amino acids only starts at position 1283 in the cDNA sequence and extends to the poly(A) tail. Sequences related to the 5' untranslated region of PAG 1 are also found downstream of procyclin genes in other loci, but the 3' coding region is unique to Pro A. This suggests that there are related PAGs which are coordinately transcribed with procyclin genes from different loci.
...
PMID:A procyclin-associated gene in Trypanosoma brucei encodes a polypeptide related to ESAG 6 and 7 proteins. 143 65

Yeast RNA polymerase II initiation factor b copurifies with three polypeptides of 85, 73, and 50 kilodaltons and with a protein kinase that phosphorylates the carboxyl-terminal repeat domain (CTD) of the largest polymerase subunit. The gene that encodes the 73-kilodalton polypeptide, designated TFB1, was cloned and found to be essential for cell growth. The deduced protein sequence exhibits no similarity to those of protein kinases. However, the sequence is similar to that of the 62-kilodalton subunit of the HeLa transcription factor BFT2, suggesting that this factor is the human counterpart of yeast factor b. Immunoprecipitation experiments using antibodies to the TFB1 gene product demonstrate that the transcriptional and CTD kinase activities of factor b are closely associated with an oligomer of the three polypeptides. Photoaffinity labeling with 3'-O-(4-benzoyl)benzoyl-ATP (adenosine triphosphate) identified an ATP-binding site in the 85-kilodalton polypeptide, suggesting that the 85-kilodalton subunit contains the catalytic domain of the kinase.
...
PMID:Cloning of a subunit of yeast RNA polymerase II transcription factor b and CTD kinase. 144

1. A protein kinase type II was purified from calf thymus chromatin using ammonium sulphate fractionation, ion exchange chromatography on DEAE and phosphocellulose and affinity chromatography on phosvitin- and casein-sepharose columns. 2. The enzyme moves as a single band in non-denaturing gel electrophoresis at pH 8.3, which coincides with the enzyme activity assayed on gel slices. 3. Sodium dodecyl sulphate gel electrophoresis shows three separate polypeptide chains having M(r) of 40,000, 38,000 and 25,000, respectively. The native M(r) was about 130,000, as measured by HPLC on Superose 12 column, suggesting a subunit structure of alpha, alpha', beta 2 type. The enzyme incubated with [gamma 32P]ATP or [gamma 32P]GTP as phosphoryl donors undergoes autophosphorylation in the M(r) = 25,000 subunit. 4. The enzyme phosphorylates casein (Km = 7 microM) and phosvitin (Km = 5 microM) but not histones and was strongly deactivated by Zn2+ ions (I50 = 0.05 mM) and heparin (I50 = 0.1 micrograms/ml). 5. The enzyme seems to be the major phosphorylating system present in the 0.35 M NaCl chromatin extract of calf thymus. The RNA polymerase II from calf thymus and RNA polymerase from E. coli are both phosphorylated by protein kinase NII. The effect of phosphorylation, which causes a remarkable increase of DNA transcription rate, was studied in vitro and extensively discussed.
...
PMID:Protein kinase NII from calf thymus chromatin. Isolation, characterization and some functional properties. 145 14

Yeast RNA polymerase II initiation factor e was purified to homogeneity and identified by biochemical criteria as the counterpart of human transcription factor IIB. Factor e was essential for initiation of transcription from yeast and mammalian promoters in a reconstituted yeast transcription system. Activity resided in a single polypeptide of approximately 41 kDa, identified by peptide sequence analysis as the product of the SUA7 gene. Factor e interacted specifically with RNA polymerase II, consistent with a proposed role in determining the start site of transcription.
...
PMID:Yeast RNA polymerase II initiation factor e: isolation and identification as the functional counterpart of human transcription factor IIB. 145 10

The Saccharomyces cerevisiae RNA polymerase III transcription factor (TF)IIIB has been assembled from three components. An assembly pathway of these polypeptides, which specifies their interactions, has been determined. The TATA-binding protein, TBP, and the TFIIB-related BRF1 gene product BRF, together reconstitute the transcription factor activity and TFIIC-dependent DNA-binding activity of the B' component of TFIIIB. BRF alone weakly binds to a TFIIIC-tRNA gene complex; TBP greatly stabilizes this interaction. B" transcription factor activity is recovered with its previously identified 90 kd polypeptide from SDS-polyacrylamide gels. Incorporation of the 90 kd B" protein into the transcription complex requires TBP. The heparin-resistant TFIIIB-DNA complex retains all three of its constituent proteins, TBP, BRF, and B".
...
PMID:The role of the TATA-binding protein in the assembly and function of the multisubunit yeast RNA polymerase III transcription factor, TFIIIB. 145 36

In the enteric bacterium, Escherichia coli, acyl coenzyme A synthetase (fatty acid:CoA ligase (AMP-forming) EC 6.2.1.3) activates exogenous long-chain fatty acids concomitant with their transport across the inner membrane into metabolically active CoA thioesters. These compounds serve as substrates for acyl-CoA dehydrogenase in the first step in the process of beta-oxidation. The acyl-CoA synthetase structural gene, fadD, has been identified on clone 6D1 of the Kohara E. coli gene library and by a process of subcloning and complementation analyses shown to be contained on a 2.2-kilobase NcoI-ClaI fragment of genomic DNA. The polypeptide encoded within this DNA fragment was identified following T7 RNA polymerase-dependent induction and estimated to be M(r) = 62,000 using SDS-polyacrylamide gel electrophoresis. The N-terminal amino acid sequence of acyl-CoA synthetase was determined by automated sequencing to be Met-Lys-Lys-Val-Trp-Leu-Asn-Arg-Tyr-Pro. Sequence analysis of the 2.2-kilobase NcoI-ClaI fragment revealed a single open reading frame encoding these amino acids as the first 10 residues of a protein with a molecular weight of 62,028. The initiation codon for methionine was TTG. Primer extension of total in vivo mRNA from two fadD-specific oligonucleotides defined the transcriptional start at an adenine residue 60 base pairs upstream from the predicted translational start site. Two FadR operator sites of the fadD gene were identified at positions -13 to -29 (OD1) and positions -99 to -115 (OD2) by DNase I footprinting. Comparisons of the predicted amino acid sequence of the E. coli acyl-CoA synthetase to the deduced amino acid sequences of the rat and yeast acyl-CoA synthetases and the firefly luciferase demonstrated that these enzymes shared a significant degree of similarity. Based on the similar reaction mechanisms of these four enzymes, this similarity may define a region required for the same function.
...
PMID:Cloning, sequencing, and expression of the fadD gene of Escherichia coli encoding acyl coenzyme A synthetase. 146 45

The nucleotide sequence of the gene coding for the plastid-encoded alpha subunit of DNA-dependent RNA polymerase from the cryptomonad alga Pyrenomonas salina was determined. The deduced amino-acid sequence, corresponding to a 35.2 kDa polypeptide, was compared to homologues from other organisms. Evolutionary relationships were analyzed in detail by the parsimony method together with bootstrap analysis. The deduced phylogenetic tree shows that the cryptomonad gene is the most ancient type of known plastid-encoded RNA polymerase.
...
PMID:Evolutionary analysis of the plastid-encoded gene for the alpha subunit of the DNA-dependent RNA polymerase of Pyrenomonas salina (Cryptophyceae). 147 79

The molecular characterization of an additional DNA species (pAL2-1) which was identified previously in a long-lived extrachromosomal mutant (AL2) of Podospora anserina revealed that this element is a mitochondrial linear plasmid. pAL2-1 is absent from the corresponding wild-type strain, has a size of 8395 bp and contains perfect long terminal inverted repeats (TIRs) of 975 bp. Exonuclease digestion experiments indicated that proteins are covalently bound at the 5' termini of the plasmid. Two long, non-overlapping open reading frames, ORF1 (3,594 bp) and ORF2 (2847 bp), have been identified, which are located on opposite strands and potentially encode a DNA and an RNA polymerase, respectively. The ORF1-encoded polypeptide contains three conserved regions which may be responsible for a 3'-5' exonuclease activity and the typical consensus sequences for DNA polymerases of the D type. In addition, an amino-acid sequence motif (YSRLRT), recently shown to be conserved in terminal proteins from various bacteriophages, has been identified in the amino-terminal part of the putative protein. According to these properties, this first linear plasmid identified in P. anserina shares all characteristics with invertrons, a group of linear mobile genetic elements.
...
PMID:The linear mitochondrial plasmid pAL2-1 of a long-lived Podospora anserina mutant is an invertron encoding a DNA and RNA polymerase. 147 81

Incubation of the E. coli RNA polymerase with a polypeptide factor from the protozoan Tetrahymena reduces the affinity of the holoenzyme for DNA. SDS-polyacrylamide gel electrophoresis of the peptide-treated RNA polymerase showed that the band pattern of the polymerase subunits was strongly altered. The three large subunits, beta', beta and sigma, disappear and a high number of rapidly migrating bands appeared. However, a brief heat treatment of the samples almost restored the original RNA polymerase subunit composition, and in addition a high molecular weight protein band approximately 240 kDa appeared. It is suggested that the Tetrahymena peptide specifically binds to the RNA polymerase and changes the structures of the large subunits.
...
PMID:A peptide from Tetrahymena disrupts subunit organization of E. coli RNA polymerase. 147 89

The P2 ogr gene encodes a 72-amino-acid protein required for P2 late gene expression. This gene was defined originally by a class of compensatory mutations which overcome the block to P2 late transcription imposed by a host mutation, rpoA109, in the gene encoding the alpha subunit of Escherichia coli RNA polymerase. Spontaneous compensatory ogr mutations substitute a Cys for a Tyr residue at amino acid 42 in the Ogr polypeptide. Using suppression of an ogr amber mutation and site-directed oligonucleotide mutagenesis, we have studied the effect of amino acid substitutions at this position in Ogr. Substitution of charged residues at this site renders Ogr protein inactive, in rpoA+ and rpoA109 strains. While 11 different amino acids are capable of replacing the wild-type Tyr-42 to allow P2 growth to varying degrees in a wild-type E. coli strain, only three of these allow phage growth in strains carrying the rpoA109 mutation. Phages carrying Cys or Ala in place of Tyr-42 gave burst sizes at least as high as P2 ogr+ in a rpoA+ strain; a Gly substitution also allowed P2 to grow in either a rpoA+ or rpoA109 background, but markedly reduced the burst size. These results are consistent with a direct interaction between Ogr and the alpha subunit of E. coli RNA polymerase in positive control of P2 late transcription, and indicate that the block imposed by the rpoA109 mutation is due to steric hindrance.
...
PMID:Site-directed mutagenesis of an amino acid residue in the bacteriophage P2 ogr protein implicated in interaction with Escherichia coli RNA polymerase. 148 87


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>

---