Summary information and primary citation
- PDB-id
- 1xs9; SNAP-derived features in text and JSON formats;
DNAproDB
- Class
- transcription-DNA
- Method
- NMR
- Summary
- A model of the ternary complex formed between mara, the alpha-ctd of RNA polymerase and DNA
- Reference
- Dangi B, Gronenborn AM, Rosner JL, Martin RG (2004): "Versatility of the carboxy-terminal domain of the alpha subunit of RNA polymerase in transcriptional activation: use of the DNA contact site as a protein contact site for MarA." Mol.Microbiol., 54, 45-59. doi: 10.1111/j.1365-2958.2004.04250.x.
- Abstract
- The transcriptional activator, MarA, interacts with RNA polymerase (RNAP) to activate promoters of the mar regulon. Here, we identify the interacting surfaces of MarA and of the carboxy-terminal domain of the alpha subunit of RNAP (alpha-CTD) by NMR-based chemical shift mapping. Spectral changes were monitored for a MarA-DNA complex upon titration with alpha-CTD, and for alpha-CTD upon titration with MarA-DNA. The mapping results were confirmed by mutational studies and retention chromatography. A model of the ternary complex shows that alpha-CTD uses a '265-like determinant' to contact MarA at a surface distant from the DNA. This is unlike the interaction of alpha-CTD with the CRP or Fis activators where the '265 determinant' contacts DNA while another surface of the same alpha-CTD molecule contacts the activator. These results reveal a new versatility for alpha-CTD in transcriptional activation.
