Figure 2.

A, Transcriptional complex components. Ac, acetylated lysine; BRD4, bromodomain and extraterminal protein 4; P, phosphorylation; PTEFb, positive transcription elongation factor b; RNA Pol II, RNA polymerase II; TF, transcription factor. B, At typical enhancers, BRD4 binds its ligand, Ac, and becomes a scaffold for recruiting Mediator, transcription factors, and PTEFb to phosphorylate RNA Pol II at the target gene promoter, thereby initiating transcription. C, Latent and super‐enhancers are densely packed with transcriptional complex components. The abundance of transcriptional machinery and BRD4 result in elevated levels of gene transcription [Color figure can be viewed at wileyonlinelibrary.com]