Fig. 1: Transcriptional enhancers and super-enhancers activate gene transcription.
From: Super-enhancers and the super-enhancer reader BRD4: tumorigenic factors and therapeutic targets
A, B The BET bromodomain protein BRD4 recognizes acetylated (Ac) histone H3 lysine 27, binds to and activates enhancers (A) and super-enhancers (B). BRD4 recruits the positive transcription elongation factor b (P-TEFb) and Mediator, leading to RNA Polymerase II (RNA Pol II) activation and binding to enhancer- and super-enhancer-associated gene promoter, transcriptional activation and target gene over-expression. As super-enhancers are bound by much larger clusters of BRD4 proteins, super-enhancer-associated oncogenes are transcribed at substantially higher levels than enhancer-associated genes.
