Mediator Complex

**Semantic type:** Amino Acid, Peptide, or Protein

**Definition:** A protein complex that is involved in the initiation of transcription. This complex is composed of over 30 protein subunits, which binds to the RNA polymerase II holoenzyme complex and facilitates the interaction of transcription factors with the polymerase.

**Synonyms:** - Mediator - Mediator Coactivator - Mediator Coactivator Complex - Mediator of Activation - Mediator of RNA Polymerase II Transcription