Acetyllysine-binding and function of bromodomain-containing proteins in chromatin

Acetylated histones are generally associated with active chromatin. The bro modomain has recently been identified as a protein module capable of bindin g to acetylated lysine residues, and hence is able to mediate the recruitme nt of factors to acetylated chromatin. Functional studies of bromodomain-co ntaining proteins indicate how this domain contributes to the activity of a number of nuclear factors including histone acetyltransferases and chromat in remodelling complexes. Here, we review the characteristics of acetyllysi ne-binding by bromodomains, discuss associated domains found in these prote ins, and address the function of the bromodomain in the context of chromati n. Finally, the modulation of bromodomain binding by neighbouring post-tran slational modifications within histone tails might provide a mechanism thro ugh which combinations of covalent marks could exert control on chromatin f unction.