Involvement of satellite I noncoding RNA in regulation of chromosome segregation

Human centromeres consist of repetitive sequences from which satellite I noncoding RNA s are transcribed. We found that knockdown of satellite I RNA causes abnormal chromosome segregation and generation of nuclei with a grape‐shape phenotype. Co‐immunoprecipitation experiments showed that satellite I RNA associates with Aurora B , a component of the chromosome passenger complex ( CPC ) regulating proper attachment of microtubules to kinetochores, in mitotic HeLa cells. Satellite I RNA was also shown to associate with INCENP , another component of the CPC . In addition, depletion of satellite I RNA resulted in up‐regulation of kinase activity of Aurora B and delocalization of the CPC from the centromere region. These results suggest that satellite I RNA is involved in chromosome segregation through controlling activity and centromeric localization of Aurora B kinase.