2hzm
From Proteopedia
|
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 with PO4 as ligand. 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 Wed Nov 21 12:04:13 2007
