Serine/threonine-protein kinase which mediates both meiotic and mitotic chromosome segregation. Required for histone H3 'Ser-10' phosphorylation. Phosphorylates mei-S332 within residues 124-126 and stabilizes its association with centromeres during meiosis. ATP + L-seryl-[protein] = ADP + H(+) + O-phospho-L-seryl-[protein] ATP + L-threonyl-[protein] = ADP + H(+) + O-phospho-L-threonyl-[protein] Interacts with Incenp and Cdc37. Meiotic and mitotic chromosomes. During each division, relocates to the midbody microtubules. Ubiquitously expressed at very high levels in embryo. Expressed at low levels during larval stages, and at higher levels in female adults (at protein level). Belongs to the protein kinase superfamily. Ser/Thr protein kinase family. Aurora subfamily.