Practice question

Acetyl-lysine recognition is mediated by evolutionarily conserved bromodomain, an all-alpha bundle of about 110 amino acids forming hydrophobic pocket that accommodates acetylated side chain via hydrogen bond to conserved asparagine. Found in many transcriptional co-activators including p300, SWI/SNF subunits Brg1 and TAF1, bromodomains anchor complexes to hyperacetylated promoters and enhancers, stabilizing pre-initiation complex assembly. Adjacent bromodomains in BET proteins bind multiple acetyl marks cooperatively. Binding is abolished upon deacetylation by HDACs, highlighting reversible recruitment mechanism coupling acetylation dynamics to gene expression activation and elongation.