Allosteric transcriptional regulation via changes in the overall topology of the core promoter

Abstract

Transcription factor shape-shifts DNA Controlling when a gene is expressed or repressed is vital for cellular metabolism and development. In Escherichia coli , a copper-sensing transcription factor, CueR, can repress or activate expression when bound at exactly the same site in the gene promoter. Philips et al. used x-ray crystallography to show that CueR dramatically changes the topology of the DNA upon binding copper but does not affect protein-DNA contacts. The DNA shape change allows RNA polymerase to bind the promoter and transcribe the gene. Science , this issue p. 877