Bromodomain-containing protein 2; Bromodomain-containing protein 3; Bromodomain-containing protein 4 (BRD2; BRD3; BRD4)

Bromodomain-containing protein 2, 3, and 4 (BRD2, BRD3, BRD4) are nuclear, chromatin-associated proteins that read acetylated lysine marks on histones via conserved bromodomains, thereby regulating transcriptional activity, cellular identity, and the cell cycle through recruitment of transcriptional machinery, cofactors, and chromatin modifiers. As members of the BET family, they play pivotal roles in cell proliferation, apoptosis, DNA damage response, and immune regulation. Dysregulation or overexpression of these proteins is strongly associated with cancer progression, inflammatory diseases, and other pathologies, making them high-priority therapeutic targets. Clinically, BET inhibitors (such as JQ1) disrupt their function by blocking bromodomain-histone interactions, suppressing oncogenic transcription such as MYC, but their development is challenged by toxicity and resistance.

Other names

RING3Bromodomain and Extra-Terminal domain proteins

Inhibition of bromodomain-acetylated lysine binding (blocks recruitment of transcriptional regulators to chromatin). Suppression of transcriptional activation of oncogenes (especially MYC and other cell cycle regulators). Disruption of enhancer-promoter communications and super-enhancer assembly.