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1rio
From Proteopedia
Structure of bacteriophage lambda cI-NTD in complex with sigma-region4 of Thermus aquaticus bound to DNA
Overview
The cI protein of bacteriophage lambda (lambdacI) activates transcription by binding a DNA operator just upstream of the promoter and interacting with the RNA polymerase sigma subunit domain 4 (sigma(4)). We determined the crystal structure of the lambdacI/sigma(4)/DNA ternary complex at 2.3 A resolution. There are no conformational changes in either protein, which interact through an extremely small interface involving at most 6 amino acid residues. The interactions of the two proteins stabilize the binding of each protein to the DNA. The results provide insight into how activators can operate through a simple cooperative binding mechanism but affect different steps of the transcription initiation process.
About this Structure
1RIO is a Protein complex structure of sequences from Enterobacteria phage lambda and Thermus aquaticus. Full crystallographic information is available from OCA.
Reference
Structure of a ternary transcription activation complex., Jain D, Nickels BE, Sun L, Hochschild A, Darst SA, Mol Cell. 2004 Jan 16;13(1):45-53. PMID:14731393 Page seeded by OCA on Sat May 3 07:32:44 2008
