Serine/threonine-protein kinase component of the chromosomal passenger complex (CPC), a complex that acts as a key regulator of mitosis (  ). The CPC complex has essential functions at the centromere in ensuring correct chromosome alignment and segregation and is required for chromatin-induced microtubule stabilization and spindle assembly (  ). Involved in the bipolar attachment of spindle microtubules to kinetochores and is a key regulator for the onset of cytokinesis during mitosis . Required for central/midzone spindle assembly and cleavage furrow formation (, ). Key component of the cytokinesis checkpoint, a process required to delay abscission to prevent both premature resolution of intercellular chromosome bridges and accumulation of DNA damage: phosphorylates CHMP4C, leading to retain abscission-competent VPS4 (VPS4A and/or VPS4B) at the midbody ring until abscission checkpoint signaling is terminated at late cytokinesis (, ). AURKB phosphorylates the CPC complex subunits BIRC5/survivin, CDCA8/borealin and INCENP ( ). Phosphorylation of INCENP leads to increased AURKB activity ( ). Other known AURKB substrates involved in centromeric functions and mitosis are CENPA, DES/desmin, GPAF, KIF2C, NSUN2, RACGAP1, SEPTIN1, VIM/vimentin, HASPIN, and histone H3 (   ). A positive feedback loop involving HASPIN and AURKB contributes to localization of CPC to centromeres . Phosphorylation of VIM controls vimentin filament segregation in cytokinetic process, whereas histone H3 is phosphorylated at 'Ser-10' and 'Ser-28' during mitosis (H3S10ph and H3S28ph, respectively) (, ). AURKB is also required for kinetochore localization of BUB1 and SGO1 (, ). Phosphorylation of p53/TP53 negatively regulates its transcriptional activity . Key regulator of active promoters in resting B- and T-lymphocytes: acts by mediating phosphorylation of H3S28ph at active promoters in resting B-cells, inhibiting RNF2/RING1B-mediated ubiquitination of histone H2A and enhancing binding and activity of the USP16 deubiquitinase at transcribed genes (By similarity). Acts as an inhibitor of CGAS during mitosis: catalyzes phosphorylation of the N-terminus of CGAS during the G2-M transition, blocking CGAS liquid phase separation and activation, and thereby preventing CGAS-induced autoimmunity . Phosphorylates KRT5 during anaphase and telophase (By similarity).
Subcellular locations: Nucleus, Chromosome, Chromosome, Centromere, Chromosome, Centromere, Kinetochore, Cytoplasm, Cytoskeleton, Spindle, Midbody
Localizes on chromosome arms and inner centromeres from prophase through metaphase and then transferring to the spindle midzone and midbody from anaphase through cytokinesis . Colocalized with gamma tubulin in the midbody . Proper localization of the active, Thr-232-phosphorylated form during metaphase may be dependent upon interaction with SPDYC . Colocalized with SIRT2 during cytokinesis with the midbody . Localization (and probably targeting of the CPC) to the inner centromere occurs predominantly in regions with overlapping mitosis-specific histone phosphorylations H3pT3 and H2ApT12 .
High level expression seen in the thymus. It is also expressed in the spleen, lung, testis, colon, placenta and fetal liver. Expressed during S and G2/M phase and expression is up-regulated in cancer cells during M phase.
Not expressed in normal liver, high expression in metastatic liver.