Component of the Mediator complex, a coactivator involved in the regulated transcription of nearly all RNA polymerase II-dependent genes. Mediator functions as a bridge to convey information from gene-specific regulatory proteins to the basal RNA polymerase II transcription machinery. Mediator is recruited to promoters by direct interactions with regulatory proteins and serves as a scaffold for the assembly of a functional preinitiation complex with RNA polymerase II and the general transcription factors.Furumoto T., Submitted (APR-2003) to the EMBL/GenBank/DDBJ databases.Submitted (APR-2003) to the EMBL/GenBank/DDBJ databases.Gregory S.G., Nature 441:315-321(2006).