Mediator of RNA polymerase II transcription subunit 22 is an enzyme that in humans is encoded by the MED22 gene. This gene is located in the surfeit gene cluster, a group of very tightly linked housekeeping genes that do not share sequence similarity. The gene is oriented in a head-to-head fashion with RPL7A (SURF3) and the two genes share a bidirectional promoter. The encoded proteins are localized to the cytoplasm. Two alternative transcript variants encoding different isoforms have been identified for this gene. [provided by RefSeq].
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.