Aurora B belongs to Serine/threonine kinase family, Aurora subfamily. Predicted molecular weight 39 kD. This kinase is highly expressed in thymus and many cancers and is also expressed in the spleen, lung, testis, colon, placenta and fetal liver. Aurora B is expressed during S and G2/M phase and is up regulated in cancer cells during M phase. Aurora B localizes to centromeres in early mitosisand then the spindle midzone in anaphase and is required for histoneH3 phosphorylation, chromosome alignment, centrosome maturation, activation of the spindle assembly checkpoint and cytokinesis. The Poly6361 antibody recognizes human phospho-Aurora B (Thr232) and has been shown to be useful for immunoflorence staining.