Acetylated Histone Tail Peptides Induce Structural Rearrangements in the RSC Chromatin Remodeling Complex*
- ↵2 To whom correspondence should be addressed: Dept. of Cell Biology, Harvard Medical School, 240 Longwood Ave., Boston, MA 02115. Tel.: 617-432-4090; Fax: 617-432-1144; E-mail: twalz{at}hms.harvard.edu.
Abstract
Post-translational acetylation of histone tails is often required for the recruitment of ATP-dependent chromatin remodelers, which in turn mobilize nucleosomes on the chromatin fiber. Here we show that the lower lobe of the ATP-dependent chromatin remodeler RSC exists in a dynamic equilibrium and can be found extended away or retracted against the tripartite upper lobe of the complex. Extension of the lower lobe increases the size of a central cavity that has been proposed to be the nucleosome binding site. We show that the presence of acetylated histone 3 N-terminal tail peptides stabilizes the lower lobe of RSC in the retracted state, suggesting that domains recognizing the acetylated histone tails reside at the interface between the two lobes. Based on three-dimensional reconstructions, we propose a model for the interaction of RSC with acetylated nucleosomes.
- Received April 27, 2007.
- Revision received May 21, 2007.
- The American Society for Biochemistry and Molecular Biology, Inc.
