Structure of a RSC–nucleosome complex and insights into chromatin remodeling

Publisher Website
Google Scholar
Abstract
The ATP-dependent chromatin-remodeling complexes are involved in repositioning, evicting and restructuring nucleosomes. The EM reconstruction of the RSC remodeler in complex with a nucleosome gives structural insights into remodeling. ATP-dependent chromatin-remodeling complexes, such as RSC, can reposition, evict or restructure nucleosomes. A structure of a RSC–nucleosome complex with a nucleosome determined by cryo-EM shows the nucleosome bound in a central RSC cavity. Extensive interaction of RSC with histones and DNA seems to destabilize the nucleosome and lead to an overall ATP-independent rearrangement of its structure. Nucleosomal DNA appears disordered and largely free to bulge out into solution as required for remodeling, but the structure of the RSC–nucleosome complex indicates that RSC is unlikely to displace the octamer from the nucleosome to which it is bound. Consideration of the RSC–nucleosome structure and published biochemical information suggests that ATP-dependent DNA translocation by RSC may result in the eviction of histone octamers from adjacent nucleosomes.