Functional dissection of Escherichia coli promoters: information in the transcribed region is involved in late steps of the overall process
Kammerer, W.; Deuschle, U.; Gentz, R.; Bujard, H.
EMBO Journal 5(11): 2995-3000
1986
ISSN/ISBN: 0261-4189 PMID: 3539590 Document Number: 285436
After binding to a promoter Escherichia coli RNA polymerase is in contact with a region of about 70 bp. Around 20 bp of this sequence are transcribed. Information encoded within this transcribed region is involved in late steps of the functional program of a promoter. By changing such 'downstream' sequences promoter strength in vivo can be varied more than 10-fold. By contrast, information for early steps of the promoter program such as recognition by the enzyme and formation of a stable complex resides in a central core region of about 35 bp. Our data show that the strength of a promoter can be limited at different levels of the overall process. Consequently prmoters of identical strength can exhibit different structures due to an alternate optimization of their program.