Mediator complex (Mediator)

The Mediator complex is a large, evolutionarily conserved **multiprotein complex** that acts as a transcriptional coactivator in all eukaryotes[1]. It serves as a critical regulatory hub by physically bridging specific DNA-bound transcription factors with the general RNA polymerase II transcription machinery, thereby enabling regulated expression of nearly all protein-coding genes[1][5][7]. The Mediator complex is structurally modular, comprising at least three main modules (Head, Middle, Tail) and a reversible kinase module (CDK8, MED12, MED13, and Cyclin C) that modulates its activity[3][6][8]. It has both basal and regulatory functions in gene transcription, integrating diverse signaling pathways and effecting epigenetic regulation, mRNA processing, and super-enhancer function[5][7]. Mutations and dysregulation of Mediator subunits are implicated in a range of diseases, including cancer and developmental disorders, highlighting its essential biological and clinical relevance[5][7]. There are currently no approved small molecules or biologics that specifically target the Mediator complex for therapeutic purposes.

Other names

Mediator (coactivator)Mediator transcriptional coactivator complexMED complex

Not applicable, as there are no clinically approved drugs directly targeting the Mediator complex.