Structural highlights
Function
[RPC1_LAMBD] Repressor protein CI allows phage lambda to reside inactively in the chromosome of its host bacterium. This lysogenic state is maintained by binding of regulatory protein CI to the OR and OL operators, preventing transcription of proteins necessary for lytic development. [Q9EZJ8_THEAQ] Sigma factors are initiation factors that promote the attachment of RNA polymerase to specific initiation sites and are then released (By similarity).[RuleBase:RU000715]
Evolutionary Conservation
Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.
Publication Abstract from PubMed
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.
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[1]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
See Also
References
- ↑ Jain D, Nickels BE, Sun L, Hochschild A, Darst SA. Structure of a ternary transcription activation complex. Mol Cell. 2004 Jan 16;13(1):45-53. PMID:14731393
