In vitro transcriptional analysis of TyrR-mediated activation of the mtr and tyrP+3 promoters of Escherichia coli.
AUTOR(ES)
Yang, J
RESUMO
In order to understand the mechanism by which the TyrR protein activates transcription from the mtr and tyrP+3 promoters, we have carried out in vitro transcription experiments with supercoiled DNA templates. We have shown that addition of the histone-like protein HU or integration host factor (IHF) greatly inhibited the transcription from the mtr and tyrP+3 promoters. In the presence of phenylalanine, the wild-type TyrR protein, but not a mutant TyrR protein (activation negative), was able to relieve the HU- or IHF-mediated inhibition of transcription. In contrast, the alleviation of the HU- or IHF-mediated transcription inhibition by the wild-type TyrR protein did not occur when a mutant RNA polymerase with a C-terminally truncated alpha subunit was used to carry out the transcription reaction.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=178520Documentos Relacionados
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