p300CREBbinding

The p300 CREB binding domain, often abbreviated as CBP/p300, refers to a region within the CREB-binding protein (CBP) and its paralog p300. CBP and p300 are large transcriptional coactivators that play critical roles in regulating gene expression. They possess intrinsic histone acetyltransferase (HAT) activity, meaning they can acetylate histone proteins, which in turn influences chromatin structure and gene accessibility.

The CREB binding domain specifically interacts with the transcription factor CREB (cAMP response element-binding protein). CREB is a key regulator of cellular responses to various extracellular signals, including hormones, neurotransmitters, and growth factors, often mediated by cyclic AMP (cAMP). When activated, CREB binds to specific DNA sequences called cAMP response elements (CREs) in the promoter regions of target genes.

The interaction between the p300/CBP CREB binding domain and CREB is crucial for its transcriptional function. This binding event recruits the coactivator complex, including CBP/p300, to the CRE-containing promoters. The HAT activity of CBP/p300 then acetylates histones, promoting a more open chromatin structure that facilitates the assembly of the transcription machinery and leads to increased gene transcription. This interaction is therefore fundamental for numerous cellular processes, including learning, memory, and cellular survival.