Autoregulation of the Escherichia coli melR promoter: repression involves four molecules of MelR.
The Escherichia coli MelR protein is a transcription activator that autoregulates its own promoter by repressing transcription initiation. Optimal repression requires MelR binding to a site that overlaps the melR transcription start point and to upstream sites. In this work, we have investigated the different determinants needed for optimal repression and their spatial requirements. We show that repression requires a complex involving four DNA-bound MelR molecules, and that the global CRP regulator plays little or no role.
Samarasinghe
Shivanthi
S
School of Biosciences, The University of Birmingham, Edgbaston, Birmingham B15 2TT, UK.
El-Robh
Mohamed Samir
MS
Grainger
David C
DC
Zhang
Wenke
W
Soultanas
Panos
P
Busby
Stephen J W
SJ
D001665:Binding Sites; D002373:Cyclic AMP Receptor Protein / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000235:genetics* / Q000378:metabolism / Q000648:ultrastructure; D004926:Escherichia coli / Q000235:genetics*; D029968:Escherichia coli Proteins / Q000235:genetics* / Q000378:metabolism / Q000648:ultrastructure; D015964:Gene Expression Regulation, Bacterial; D006706:Homeostasis; D018625:Microscopy, Atomic Force; D011401:Promoter Regions, Genetic; D012097:Repressor Proteins / Q000235:genetics* / Q000378:metabolism / Q000648:ultrastructure; D015534:Trans-Activators / Q000235:genetics* / Q000378:metabolism / Q000648:ultrastructure; D014157:Transcription Factors / Q000378:metabolism
D002373:Cyclic AMP Receptor Protein; D004268:DNA-Binding Proteins; D029968:Escherichia coli Proteins; C077649:MelR protein, E coli; D012097:Repressor Proteins; D015534:Trans-Activators; D014157:Transcription Factors; C481662:crp protein, E coli