Summary information and primary citation

PDB-id
4wls; SNAP-derived features in text and JSON formats; DNAproDB
Class
transcription regulator-DNA
Method
X-ray (2.105 Å)
Summary
Crystal structure of the metal-free (repressor) form of e. coli cuer, a copper efflux regulator, bound to copa promoter DNA
Reference
Philips SJ, Canalizo-Hernandez M, Yildirim I, Schatz GC, Mondragon A, O'Halloran TV (2015): "Allosteric transcriptional regulation via changes in the overall topology of the core promoter." Science, 349, 877-881. doi: 10.1126/science.aaa9809.
Abstract
Many transcriptional activators act at a distance from core promoter elements and work by recruiting RNA polymerase through protein-protein interactions. We show here how the prokaryotic regulatory protein CueR both represses and activates transcription by differentially modulating local DNA structure within the promoter. Structural studies reveal that the repressor state slightly bends the promoter DNA, precluding optimal RNA polymerase-promoter recognition. Upon binding a metal ion in the allosteric site, CueR switches into an activator conformation. It maintains all protein-DNA contacts but introduces torsional stresses that kink and undertwist the promoter, stabilizing an A-form DNA-like conformation. These factors switch on and off transcription by exerting dynamic control of DNA stereochemistry, reshaping the core promoter and making it a better or worse substrate for polymerase.

Cartoon-block schematics in six views (download the tarball)

PyMOL session file Download PDB file View in 3Dmol.js