2hzm
From Proteopedia
| |||||||
| , resolution 2.4Å | |||||||
|---|---|---|---|---|---|---|---|
| Ligands: | |||||||
| Gene: | SRB2, HRS2, MED20 (Saccharomyces cerevisiae), SRB5, MED18 (Saccharomyces cerevisiae) | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
Structure of the Mediator head subcomplex Med18/20
Overview
The Mediator head module stimulates basal RNA polymerase II (Pol II) transcription and enables transcriptional regulation. Here we show that the head subunits Med8, Med18 and Med20 form a subcomplex (Med8/18/20) with two submodules. The highly conserved N-terminal domain of Med8 forms one submodule that binds the TATA box-binding protein (TBP) in vitro and is essential in vivo. The second submodule consists of the C-terminal region of Med8 (Med8C), Med18 and Med20. X-ray analysis of this submodule reveals that Med18 and Med20 form related beta-barrel folds. A conserved putative protein-interaction face on the Med8C/18/20 submodule includes sites altered by srb mutations, which counteract defects resulting from Pol II truncation. Our results and published data support a positive role of the Med8/18/20 subcomplex in initiation-complex formation and suggest that the Mediator head contains a multipartite TBP-binding site that can be modulated by transcriptional activators.
About this Structure
2HZM is a Protein complex structure of sequences from Saccharomyces cerevisiae. Full crystallographic information is available from OCA.
Reference
Structure and TBP binding of the Mediator head subcomplex Med8-Med18-Med20., Lariviere L, Geiger S, Hoeppner S, Rother S, Strasser K, Cramer P, Nat Struct Mol Biol. 2006 Oct;13(10):895-901. Epub 2006 Sep 10. PMID:16964259
Page seeded by OCA on Thu Mar 20 17:23:38 2008
