Figure 7. Yeast bromodomain and extra-terminal domain (BET) proteins regulate transcription initiation and elongation.
Yeast BET proteins bind to regions of the genome highly acetylated at histone H4. Together with sequence-specific transcription factors (TFs), they provide a nucleation center for dynamic recruitment of TFIID and Mediator to the promoter-proximal nuclear territory. In turn, TFIID and Mediator create a platform that facilitates preinitiation complex (PIC) assembly and stimulates transcription initiation. Yeast BET proteins also affect early elongation serving as negative regulatory factors at coactivator-redundant (CR) genes and positive regulatory factors at TFIID-dependent genes.
