title: Interaction of the mediator head module with RNA polymerase II.
abstract: Mediator, a large (21 polypeptides, MW ∼1 MDa) complex conserved throughout eukaryotes, plays an essential role in control of gene expression by conveying regulatory signals that influence the activity of the preinitiation complex. However, the precise mode of interaction between Mediator and RNA polymerase II (RNAPII), and the mechanism of regulation by Mediator remain elusive. We used cryo-electron microscopy and reconstituted in vitro transcription assays to characterize a transcriptionally-active complex including the Mediator Head module and components of a minimum preinitiation complex (RNAPII, TFIIF, TFIIB, TBP, and promoter DNA). Our results reveal how the Head interacts with RNAPII, affecting its conformation and function.
authors.affiliation: Department of Cell Biology, The Scripps Research Institute, La Jolla, CA 92037, USA.
authors.forename: Gang
authors.initials: G
authors.lastname: Cai
authors.forename: Yuriy L
authors.initials: YL
authors.lastname: Chaban
authors.forename: Tsuyoshi
authors.initials: T
authors.lastname: Imasaki
authors.forename: Julio A
authors.initials: JA
authors.lastname: Kovacs
authors.forename: Guillermo
authors.initials: G
authors.lastname: Calero
authors.forename: Pawel A
authors.initials: PA
authors.lastname: Penczek
authors.forename: Yuichiro
authors.initials: Y
authors.lastname: Takagi
authors.forename: Francisco J
authors.initials: FJ
authors.lastname: Asturias
mesh_terms: D001665:Binding Sites; D020285:Cryoelectron Microscopy; D056892:Mediator Complex / Q000737:chemistry* / Q000378:metabolism / Q000648:ultrastructure; D011401:Promoter Regions, Genetic; D012319:RNA Polymerase II / Q000737:chemistry* / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000737:chemistry / Q000378:metabolism; D013329:Structure-Activity Relationship; D019473:Transcription Factors, TFII / Q000737:chemistry / Q000378:metabolism
chemical_list: D056892:Mediator Complex; D029701:Saccharomyces cerevisiae Proteins; D019473:Transcription Factors, TFII; D012319:RNA Polymerase II