| Structural highlights
2hzm is a 8 chain structure with sequence from Atcc 18824. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
| | Ligands: | |
| Related: | 1zp2, 1yke, 1ykh, 2hzs |
| Gene: | SRB2, HRS2, MED20 (ATCC 18824), SRB5, MED18 (ATCC 18824) |
| Resources: | FirstGlance, OCA, PDBe, RCSB, PDBsum |
Function
[MED20_YEAST] Component of the Mediator complex, a coactivator involved in the regulated transcription of nearly all RNA polymerase II-dependent genes. Mediator functions as a bridge to convey information from gene-specific regulatory proteins to the basal RNA polymerase II transcription machinery. The Mediator complex, having a compact conformation in its free form, is recruited to promoters by direct interactions with regulatory proteins and serves for the assembly of a functional preinitiation complex with RNA polymerase II and the general transcription factors. The Mediator complex unfolds to an extended conformation and partially surrounds RNA polymerase II, specifically interacting with the unphosphorylated form of the C-terminal domain (CTD) of RNA polymerase II. The Mediator complex dissociates from the RNA polymerase II holoenzyme and stays at the promoter when transcriptional elongation begins.[1] [2] [3] [4] [MED18_YEAST] Component of the Mediator complex, a coactivator involved in the regulated transcription of nearly all RNA polymerase II-dependent genes. Mediator functions as a bridge to convey information from gene-specific regulatory proteins to the basal RNA polymerase II transcription machinery. The Mediator complex, having a compact conformation in its free form, is recruited to promoters by direct interactions with regulatory proteins and serves for the assembly of a functional preinitiation complex with RNA polymerase II and the general transcription factors. The Mediator complex unfolds to an extended conformation and partially surrounds RNA polymerase II, specifically interacting with the unphosphorylated form of the C-terminal domain (CTD) of RNA polymerase II. The Mediator complex dissociates from the RNA polymerase II holoenzyme and stays at the promoter when transcriptional elongation begins.[5] [6] [7] [8] [9] [10]
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 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.
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[11]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
See Also
References
- ↑ Nair D, Kim Y, Myers LC. Mediator and TFIIH govern carboxyl-terminal domain-dependent transcription in yeast extracts. J Biol Chem. 2005 Oct 7;280(40):33739-48. Epub 2005 Aug 2. PMID:16076843 doi:http://dx.doi.org/M506067200
- ↑ van de Peppel J, Kettelarij N, van Bakel H, Kockelkorn TT, van Leenen D, Holstege FC. Mediator expression profiling epistasis reveals a signal transduction pathway with antagonistic submodules and highly specific downstream targets. Mol Cell. 2005 Aug 19;19(4):511-22. PMID:16109375 doi:http://dx.doi.org/10.1016/j.molcel.2005.06.033
- ↑ Takagi Y, Kornberg RD. Mediator as a general transcription factor. J Biol Chem. 2006 Jan 6;281(1):80-9. Epub 2005 Nov 1. PMID:16263706 doi:http://dx.doi.org/M508253200
- ↑ Takagi Y, Calero G, Komori H, Brown JA, Ehrensberger AH, Hudmon A, Asturias F, Kornberg RD. Head module control of mediator interactions. Mol Cell. 2006 Aug 4;23(3):355-64. PMID:16885025 doi:http://dx.doi.org/S1097-2765(06)00412-6
- ↑ Holstege FC, Jennings EG, Wyrick JJ, Lee TI, Hengartner CJ, Green MR, Golub TR, Lander ES, Young RA. Dissecting the regulatory circuitry of a eukaryotic genome. Cell. 1998 Nov 25;95(5):717-28. PMID:9845373
- ↑ Kang JS, Kim SH, Hwang MS, Han SJ, Lee YC, Kim YJ. The structural and functional organization of the yeast mediator complex. J Biol Chem. 2001 Nov 9;276(45):42003-10. Epub 2001 Sep 12. PMID:11555651 doi:http://dx.doi.org/10.1074/jbc.M105961200
- ↑ Nair D, Kim Y, Myers LC. Mediator and TFIIH govern carboxyl-terminal domain-dependent transcription in yeast extracts. J Biol Chem. 2005 Oct 7;280(40):33739-48. Epub 2005 Aug 2. PMID:16076843 doi:http://dx.doi.org/M506067200
- ↑ van de Peppel J, Kettelarij N, van Bakel H, Kockelkorn TT, van Leenen D, Holstege FC. Mediator expression profiling epistasis reveals a signal transduction pathway with antagonistic submodules and highly specific downstream targets. Mol Cell. 2005 Aug 19;19(4):511-22. PMID:16109375 doi:http://dx.doi.org/10.1016/j.molcel.2005.06.033
- ↑ Takagi Y, Kornberg RD. Mediator as a general transcription factor. J Biol Chem. 2006 Jan 6;281(1):80-9. Epub 2005 Nov 1. PMID:16263706 doi:http://dx.doi.org/M508253200
- ↑ Takagi Y, Calero G, Komori H, Brown JA, Ehrensberger AH, Hudmon A, Asturias F, Kornberg RD. Head module control of mediator interactions. Mol Cell. 2006 Aug 4;23(3):355-64. PMID:16885025 doi:http://dx.doi.org/S1097-2765(06)00412-6
- ↑ Lariviere L, Geiger S, Hoeppner S, Rother S, Strasser K, Cramer P. Structure and TBP binding of the Mediator head subcomplex Med8-Med18-Med20. Nat Struct Mol Biol. 2006 Oct;13(10):895-901. Epub 2006 Sep 10. PMID:16964259 doi:10.1038/nsmb1143
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