Mediator of RNA Pol II transcription subunit 23

Accession # and Alternate Nomenclature: AAH60759; Activator-recruited cofactor 130kDa component; cofactor required for Sp1 transcriptional activation subunit3, CRSP complex3, Sur-2 homolog, Vit. D3 receptor interacting protein complex 130kDa component, DRIP130. 

Gene transcription is a multistep process that is triggered by transcription factors.  The Mediator Complex is a multi-protein complex that acts as a molecular bridge linking transcription factors that are gene-specific to the basal transcription machinery.  This bridge is connected through direct interactions with proteins; linking DNA bound transcription factors and RNA polymerase II (Pol II). Mediator subunits control different genes and physiological processes, depending on the different transcription factors that interact with environmental stimuli.  An active mediator complex has been found to be the size of a ribosomal subunit (1).  This surface area is large enough to potentially act as a site for a multitude of different transcriptional regulators having influence on transcription initiation. The Mediator Complex supports the transcription of genes, holding diverse transcription factor initiation sites (2).

MED23 cells-also known as Mediator of RNA polymerase II transcription subunit 23 contains an active mediator complex that supports the transcription of most genes (1).  The mammalian mediator subunit MED23 is key for the Erg1 (early growth response factor 1) transcription factor in mouse embryonic stem cells (2).  The Erg1 transcription factor plays a role in cell growth regulation, cell differentiation, cell transformation and apoptosis (2).  The mediator MED23 subunit has also been found to have a correlation with the ternary complex factor Elk1. Transcript elongation that is made via Pol II is paused at the Erg1 promoter-which is activated via MAPK phosphorylation of Elk1 and the phospho-Elk1 interactions with the mediator occurring through the MED23 subunit (2). The MED23 gene is expressed in multiple spliced variant forms. 

MED23-selective antibodies were generated against unique antigenic peptide taken form the region between amino acids 650-700 in the MED23 protein, the selected peptide sequence is present in all the variants of MED23 but not found in any other protein listed in the gene bank.  The MED23 antibodies were affinity purified over immobilized antigen based chromatography, and the purified immunoglobulins are stabilized in antibody stabilization buffer.  FabGennix Int. Inc., will also provide limited quantities of antigenic blocking peptide for MED23.  Antibodies to several other Glutamate Receptor subunits are available from FabGennix International Inc.  For a complete list of antibodies please visit http://www.fabgennix.com.  FabGennix Inc. will conjugate antibodies with secondary enzymes (alk-Pase or HRP) or fluorescent probes upon request at a nominal cost.  FabGennix Int. Inc., will also provide western blot positive controls for it antibodies in ready-to-use buffer.   Limited quantities of antigenic blocking peptide is available (Please inquire before placing orders).