Energy-dependent chromatin remodelers: complex complexes and their components.

Chromatin structure is dynamically regulated such that it can be modified by a number of factors in response to a variety of signals. One class of factors that can mediate changes in chromatin structure is the ATP-dependent nucleosome remodeling complexes. Genetic and biochemical evidence supports the idea that a family of related multisubunit complexes hydrolyzes ATP in order to facilitate the rearrangement of chromatin structure. These complexes are conserved from yeast to mammals and apparently have diverse functions in modifying chromatin structure; ATP-dependent chromatin remodelers have been implicated in nucleosome deposition, nucleosome assembly, and disruption of nucleosome structure to facilitate transcriptional activation. In addition, individual components of these complexes have been linked to control of cell growth, cell cycle regulation, development, and differentiation, and they may also be targets for viral regulatory proteins. The diversity of subunit functions likely relates to effects on chromatin structure, suggesting that the regulation of chromatin structure by ATP-dependent remodelers is important in many different aspects of cellular metabolism.