Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:2.7.7.6 (RNA polymerase)
 34,946 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The promoter-specific binding of Escherichia coli RNA polymerase to the T7-A3 and the lacUV5 promoters at 0 degrees C was analyzed by DNase I footprinting. At 37 degrees C, the footprint from RNA polymerase bound to the A3 promoter is essentially the same as that reported by Galas, D.J., and Schmitz, A., (1978) Nucleic Acids Res. 5, 3157-3170 for the lacUV5 promoter. At 0 degrees C, the footprint for the A3 promoter is well defined but reduced in size. The principal difference between the 0 and 37 degrees C footprints is a region from -2 to +18 which is protected by polymerase at the higher but not at the lower temperature. In contrast, the 0 degree C footprint for the lacUV5 promoter differs substantially in character from the footprint for A3 at 0 degree C. The footprint is similar to the pattern of DNase I digestion of DNA bound to a surface; alternating regions of sensitive and protected DNA are spaced at intervals of about 10 base pairs. This region of DNase I-sensitive and -resistant DNA has the same boundaries as the 0 degree C footprint on T7-A3. Temperature shift experiments confirmed the sequence specificity of the RNA polymerase interaction with UV5 at 0 degree C. These results indicate that RNA polymerase binds specifically to each promoter sequence in a closed complex. The increased time and amounts of RNA polymerase required to form the 0 degree C footprint on the lacUV5 promoter indicate that it binds RNA polymerase more weakly than does the T7-A3 promoter. Therefore there is a correlation between the binding constant for closed complex formation estimated from kinetic measurements and the formation of the 0 degree C footprint. The -35 region of the promoter may be more important in establishing the 0 degree C footprint because the T7-A3 promoter is a better match to the consensus sequence. Conversely, the -10 region seems less important because lacUV5 is a perfect match to the consensus, whereas the T7-A3 promoter matches at only five out of seven positions. The 0 degree C footprints encompass both regions along with the spacer; the combination of these regions rather than an individual region may determine the character of the footprint and the magnitude of the binding constant.
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PMID:The 0 degree C closed complexes between Escherichia coli RNA polymerase and two promoters, T7-A3 and lacUV5. 330 80

A factor necessary for the accurate transcription of cloned Xenopus 5S genes in vitro has been isolated from soluble extracts of X. laevis ovaries. The activity of the factor was monitored by its ability to facilitate transcription of exogenous 5S genes in unfertilized egg extracts which are otherwise incompetent for 5S gene transcription. The factor was purified via ion exchange chromatography, and apparently consists of a 37,000 dalton polypeptide. This factor is necessary for the transcription of both the oocyte-type and somatic-type 5S genes of Xenopus, but is not required for, and has no detectable effect upon, the transcription of a cloned Xenopus tRNA1Met gene. The site of action of the factor has been investigated using the "footprinting" method of Galas and Schmitz (1978). The factor binds specifically to intragenic regions extending, approximately, from nucleotide positions 45 to 96 on both somatic and oocyte-type 5S genes. Additionally, this binding occurs independently of, and is not altered by, the presence of purified RNA polymerase III or unfertilized egg extracts. The probable role of this factor in transcription initiation is discussed.
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PMID:Specific interaction of a purified transcription factor with an internal control region of 5S RNA genes. 615 31

The specific binding of one or several Saccharomyces cerevisiae proteins to a segment of genes that code for different yeast tRNAs has been demonstrated with the use of the DNase I-protection "footprint" assay of Galas and Schmitz. The analyzed binding occurs near the 3' ends of the genes and is centered on an 11-base-pair DNA sequence that has been well conserved among eukaryotic tRNA genes. Others have shown the involvement of this sequence in initiating the transcription of tRNA genes by RNA polymerase III. The adenovirus gene that codes for VAI RNA also contains this conserved sequence element, and we detect binding of yeast protein(s) to this gene. Competition experiments show that a common set of proteins binds to different tRNA genes. The DNA-protein complex is quite stable at 20 degrees C and low ionic strength.
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PMID:Specific interactions of Saccharomyces cerevisiae proteins with a promoter region of eukaryotic tRNA genes. 675 66