1Z3E

Crystal Structure of Spx in Complex with the C-terminal Domain of the RNA Polymerase Alpha Subunit

Summary for 1Z3E

• Entry DOI: 10.2210/pdb1z3e/pdb
• Descriptor: Regulatory protein spx, DNA-directed RNA polymerase alpha chain, SULFATE ION, ... (4 entities in total)
• Functional Keywords: bacterial transcription regulation, disulfide stress, transcription
• Biological source: Bacillus subtilis; More
• Cellular location: Cytoplasm : O31602
• Total number of polymer chains: 2
• Total formula weight: 24455.99

Authors

Newberry, K.J.,Nakano, S.,Zuber, P.,Brennan, R.G. (deposition date: 2005-03-11, release date: 2005-10-11, Last modification date: 2024-10-30)

Primary citation

Newberry, K.J.,Nakano, S.,Zuber, P.,Brennan, R.G.
Crystal structure of the Bacillus subtilis anti-alpha, global transcriptional regulator, Spx, in complex with the {alpha} C-terminal domain of RNA polymerase
Proc.Natl.Acad.Sci.Usa, 102:15839-15844, 2005

PubMed Abstract: Spx, a global transcription regulator in Bacillus subtilis, interacts with the C-terminal domain of the alpha subunit (alphaCTD) of RNA polymerase to control gene expression under conditions of disulfide stress, which is sensed by disulfide bond formation between Spx residues C10 and C13. Here, we describe the crystal structure of the B. subtilis alphaCTD bound to oxidized Spx. Analysis of the complex reveals interactions between three regions of "anti-alpha" Spx and helix alpha1 and the "261" determinant of alphaCTD. The former contact could disrupt the interaction between alphaCTD and activator proteins or alter the DNA-bound conformation of alphaCTD, thereby repressing activator-stimulated transcription. Binding to the 261 determinant would prevent interaction between alphaCTD and region 4 of sigma(A). Intriguingly, the Spx disulfide bond is far from the alphaCTD-Spx interface, suggesting that Spx regulates transcription allosterically or through the redox-dependent creation or destruction of binding sites for additional components of the transcription machinery.

PubMed: 16249335
DOI: 10.1073/pnas.0506592102

Experimental method

X-RAY DIFFRACTION (1.5 Å)