Gene Ontology Help

Core mediator complex Overview

GO Annotations consist of four mandatory components: a gene product, a term from one of the three Gene Ontology (GO) controlled vocabularies (Molecular Function, Biological Process, and Cellular Component), a reference, and an evidence code.

Plays an essential role in gene expression regulation by acting as a bridge between DNA-binding transcription factors and the RNA polymerase II (RNAPII) transcription machinery, serving as a central scaffold within the pre-initiation complex. The Mediator complex is also targeted by sequence-specific, DNA-binding transcription factors and appears to regulate RNAPII at both the initiation and elongation stages of transcription. The Mediator complex, having a compact conformation in its free form, is recruited to promoters by direct interactions with regulatory proteins and unfolds to an extended conformation and partially surrounds RNAPII specifically interacting with the unphosphorylated form of its C-terminal domain. The Mediator complex dissociates from the RNA polymerase II holoenzyme and stays at the promoter when transcriptional elongation begins. Reversibly associates with the CKM complex (CPX-1853). Mediator lacking the CKM complex has a stimulatory effect on basal transcription. In contrast, Mediator containing the sub-complex represses basal transcription.
GO Slim Terms

The yeast GO Slim terms are higher level terms that best represent the major S. cerevisiae biological processes, functions, and cellular components. The GO Slim terms listed here are the broader parent terms for the specific terms to which this gene product is annotated, and thus represent the more general processes, functions, and components in which it is involved.

protein-macromolecule adaptor activity, cellular component assembly, protein-containing complex assembly, nucleus, organelle