The chromatin remodeler RSC prevents ectopic CENP-A assembly at pericentromeric heterochromatin

Centromeres of fission yeast consist of a central kinetochore domain and the surrounding heterochromatic domains. The boundaries between these domains are strictly fixed. However, the mechanism of establishment and maintenance of the boundaries remains elusive. Here, we report that mutation of sfh1, which encodes a core subunit of RSC chromatin remodeling complex, induced ectopic CENP-A assembly at pericentromeric heterochromatin, resulting in misloading kinetochore proteins and a chromosome segregation defect. Because ectopic CENP-A deposition was restricted to pericentromeric heterochromatin, CENP-A at the central domain spread into the pericentromeric region across the boundary. These observations indicate that RSC prevents the propagation of inappropriate kinetochore domains into pericentromeric domains.