Architecture of the Mediator head module.

ABSTRACT: Mediator is a key regulator of eukaryotic transcription, connecting activators and repressors bound to regulatory DNA elements with RNA polymerase II (Pol II). In the yeast Saccharomyces cerevisiae, Mediator comprises 25 subunits with a total mass of more than one megadalton (refs 5, 6) and is organized into three modules, called head, middle/arm and tail. Our understanding of Mediator assembly and its role in regulating transcription has been impeded so far by limited structural information. Here we report the crystal structure of the essential Mediator head module (seven subunits, with a mass of 223 kilodaltons) at a resolution of 4.3 ångströms. Our structure reveals three distinct domains, with the integrity of the complex centred on a bundle of ten helices from five different head subu

SUBMITTER: Imasaki T 

PROVIDER: S-EPMC4109712 | biostudies-literature | 2011 Jul

REPOSITORIES: biostudies-literature