Interaction of the mediator head module with RNA polymerase II

Structure. 2012 May 9;20(5):899-910. doi: 10.1016/j.str.2012.02.023.

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.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Binding Sites
  • Cryoelectron Microscopy
  • Mediator Complex / chemistry*
  • Mediator Complex / metabolism
  • Mediator Complex / ultrastructure
  • Promoter Regions, Genetic
  • RNA Polymerase II / chemistry*
  • RNA Polymerase II / metabolism*
  • Saccharomyces cerevisiae Proteins / chemistry
  • Saccharomyces cerevisiae Proteins / metabolism
  • Structure-Activity Relationship
  • Transcription Factors, TFII / chemistry
  • Transcription Factors, TFII / metabolism

Substances

  • Mediator Complex
  • Saccharomyces cerevisiae Proteins
  • Transcription Factors, TFII
  • RNA Polymerase II