CBP (also known as CREB-binding protein and CBP/p300) is a widely expressed nuclear protein that contains a bromodomain, a ZZ-type zinc domain, and TAZ-type zinc fingers. This 265 kD acetyltransferase enzyme, acetylates histones and non-histone proteins like NCOA3 coactivator and mediates c-AMP gene regulating by binding to phosphorylated CREB. CBP and phosphorylated CREB activates transcription of c-AMP responsive genes; defects in CBP result in Rubinstein-Taybi syndrome (mental retardation, craniofacial defects, heart defects). CBP is activated by TCR signaling and is involved in TNF-alpha gene expression and plays a central role in regulating gene responses to hypoxia. This protein is acetylated at multiple sites. CBP has been shown to interact with NCOA6, androgen receptor, STAT6, SRC1, Csk, FKHR, and c-jun and to form a complex with NCOA2, NCOA3, IKKA, IKKB, and IKBKG. In addition, CBP probably forms a complex with HIF1A and EP300. The Poly6064 antibody has been shown to be useful for Western blotting of the human and mouse CBP protein.