The bromodomain: A regulator of ATP-dependent chromatin remodeling?

In eukaryotes, processes requiring access to DNA are inhibited by the struc tural packaging of the genome. A number of specialized ATP-dependent chroma tin remodeling enzymes have evolved to overcome this inhibition. One subset of these enzymes, SWI/SNF, plays a critical role in the regulation of tran scription, often functioning in concert with nuclear histone acetyltransfer ases (HATs). It remains unknown how these activities are coordinated. Howev er, recent results revealing that the bromodomain, a motif common in these remodeling factors, constitutes an acetyl-lysine binding domain might provi de insight into this process. Bromodomains may serve a role analogous to th e signal transduction SH2 domain, by providing a means to recruit remodelin g complexes to acetylated chromatin regions or to allosterically modify the ir function post-recruitment.