MED23

The activation of gene transcription is a multistep process that is triggered by factors that recognize transcriptional enhancer sites in DNA. These factors work with co-activators to direct transcriptional initiation by the RNA polymerase II apparatus. The protein encoded by this gene is a subunit of the CRSP (cofactor required for SP1 activation) complex, which, along with TFIID, is required for efficient activation by SP1. This protein is also a component of other multisubunit complexes e.g. thyroid hormone receptor-(TR-) associated proteins which interact with TR and facilitate TR function on DNA templates in conjunction with initiation factors and cofactors. This protein also acts as a metastasis suppressor. Several alternatively spliced transcript variants encoding different isoforms have been described for this gene.

Full Name

Mediator Complex Subunit 23

Function

Required for transcriptional activation subsequent to the assembly of the pre-initiation complex (By similarity).

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 pre-initiation complex with RNA polymerase II and the general transcription factors. Required for transcriptional activation by adenovirus E1A protein. Required for ELK1-dependent transcriptional activation in response to activated Ras signaling.

Biological Process

Positive regulation of gene expression Source: GO_Central
Positive regulation of transcription elongation from RNA polymerase II promoter Source: ComplexPortal
Positive regulation of transcription initiation from RNA polymerase II promoter Source: ComplexPortal
Regulation of transcription, DNA-templated Source: MGI
Regulation of transcription by RNA polymerase II Source: GO_Central
RNA polymerase II preinitiation complex assembly Source: ComplexPortal
Transcription initiation from RNA polymerase II promoter Source: ProtInc

Cellular Location

Nucleus

Involvement in disease

Intellectual developmental disorder, autosomal recessive 18, with or without epilepsy (MRT18):
A disorder characterized by significantly below average general intellectual functioning associated with impairments in adaptive behavior and manifested during the developmental period.