Structural highlights
Function
MED11_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 (PIC) 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. The essential MED11/22 heterodimer specifically functions in promoting stable PIC formation.[1] [2] [3] [4]
Publication Abstract from PubMed
The X-ray crystal structure of the Head module, one-third of the Mediator of transcriptional regulation, has been determined as a complex with the C-terminal domain (CTD) of RNA polymerase II. The structure reveals multiple points of interaction with an extended conformation of the CTD; it suggests a basis for regulation by phosphorylation of the CTD. Biochemical studies show a requirement for Mediator-CTD interaction for transcription.
Structure of the Mediator Head module bound to the carboxy-terminal domain of RNA polymerase II.,Robinson PJ, Bushnell DA, Trnka MJ, Burlingame AL, Kornberg RD Proc Natl Acad Sci U S A. 2012 Oct 30;109(44):17931-5. doi:, 10.1073/pnas.1215241109. Epub 2012 Oct 15. PMID:23071300[5]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
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
- ↑ 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
- ↑ Esnault C, Ghavi-Helm Y, Brun S, Soutourina J, Van Berkum N, Boschiero C, Holstege F, Werner M. Mediator-dependent recruitment of TFIIH modules in preinitiation complex. Mol Cell. 2008 Aug 8;31(3):337-46. doi: 10.1016/j.molcel.2008.06.021. PMID:18691966 doi:http://dx.doi.org/10.1016/j.molcel.2008.06.021
- ↑ Robinson PJ, Bushnell DA, Trnka MJ, Burlingame AL, Kornberg RD. Structure of the Mediator Head module bound to the carboxy-terminal domain of RNA polymerase II. Proc Natl Acad Sci U S A. 2012 Oct 30;109(44):17931-5. doi:, 10.1073/pnas.1215241109. Epub 2012 Oct 15. PMID:23071300 doi:http://dx.doi.org/10.1073/pnas.1215241109
