Proper capturing of chromosomes by spindle microtubules is important for faithful chromosome segregation. Condensation of chromosome arms prevents chromosome entanglement in separation. Condensin, a widely conserved protein complex, is known to execute this condensation. Although Aurora B kinase is also involved in condensing mitotic chromosomes, its crucial substrates remain elusive. The present study reveals that condensin localized at kinetochores forms a rigid structure to prevent erroneous microtubule attachment. Moreover, this study discovers that histone H2A acts as a chromatin receptor of condensin, and that condensin phosphorylation by Aurora B promotes the interaction between condensin and histone H2A. During chromosome separation, Aurora B redistributes from centromeres to chromosome arm regions, thereby spatiotemporally promoting condensin association and chromosome shaping.

Program member
Yoshinori Watanabe (Institute of Molecular Cellular Biosciences)