Bromo domain

B. Bromo Domain-Containing Proteins Function in Modifiers... 

New evidence indicates that the major mediators in remodeler recruitment may be bromo and chromo domain-containing proteins. Bromo domains mediate protein binding to acetyl-lysines in histones and other proteins (Jacobson et al., 2000), and chromo domains have been shown to bind methyl-lysines (Jacobs et al., 2002). For instance, TAF1, a component of TFIID, contains two tandem bromo domains that bind selectively to multiply acetylated H4 peptides (Jacobson et al., 2000). Furthermore, the Gcn5 bromo domain preferentially binds acetylated H4 K16 (Owen et al., 2000). 

Bromo domains are found in multiple additional proteins implicated in transcriptional activation, including the RSC (remodels the structure of chromatin) complex proteins Sthl, Rscl, and Rsc2. Deletion of either bromo domain in double-bromo domain proteins Rscl and Rsc2 causes different phenotypic effects (Cairns et al., 1999). This finding indicates that all bromo domains are not alike and that they may mediate distinct biological functions even when found within the same protein. 

Fig. 1. Illustrates a model of processive nucleosomal acetylation via the Gcn5 bromo domain.

Finding the bromo domain in so many chromatin-regulating proteins reveals a potential central regulation mechanism that mediates... 

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