Interactions between the Escherichia coli cAMP receptor protein and the C-terminal domain of the alpha subunit of RNA polymerase at class I promoters.

摘要: The Escherichia coli cAMP receptor protein (CRP) is a factor that activates transcription at over 100 target promoters. At Class I CRP-dependent promoters, CRP binds immediately upstream of RNA polymerase and by making direct contacts with the C-terminal domain alpha subunit (alphaCTD). Since alphaCTD also known to interact DNA sequence elements (known as UP elements), we have constructed series semi-synthetic carrying both consensus DNA-binding site for element different positions. We previously showed that, these CRP-alphaCTD interaction CRP-UP contribute independently additively initiation. In this study, show two halves can function independently, in presence element, best location position -69.5. This suggests promoters where located -61.5, alphaCTDs are not optimally positioned. Two experiments test hypothesis presented.