MED1
Function
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 (PubMed:10406464, PubMed:11867769, PubMed:12037571, PubMed:12218053, PubMed:12556447, PubMed:14636573, PubMed:15340084, PubMed:15471764, PubMed:15989967, PubMed:16574658, PubMed:9653119). Acts as a coactivator for GATA1-mediated transcriptional activation during erythroid differentiation of K562 erythroleukemia cells (PubMed:24245781).
Post-translational modifications
Phosphorylated by MAPK1 or MAPK3 during G2/M phase which may enhance protein stability and promote entry into the nucleolus (PubMed:16314496). Phosphorylation increases its interaction with PSIP1 (PubMed:29997176).
Sequence Similarities
Belongs to the Mediator complex subunit 1 family.
Tissue Specificity
Ubiquitously expressed.
Cellular localization
- Nucleus
- A subset of the protein may enter the nucleolus subsequent to phosphorylation by MAPK1 or MAPK3.
Alternative names
ARC205, CRSP1, CRSP200, DRIP205, DRIP230, PBP, PPARBP, PPARGBP, RB18A, TRAP220, TRIP2, MED1, Mediator of RNA polymerase II transcription subunit 1, Activator-recruited cofactor 205 kDa component, Mediator complex subunit 1, Peroxisome proliferator-activated receptor-binding protein, Thyroid hormone receptor-associated protein complex 220 kDa component, Thyroid receptor-interacting protein 2, Vitamin D receptor-interacting protein complex component DRIP205, p53 regulatory protein RB18A, PPAR-binding protein, Trap220, TR-interacting protein 2, TRIP-2