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. In the complex, it may be required to direct the CPC to centromeric DNA (By similarity). May form homooligomers and homodimers. Component of the chromosomal passenger complex (CPC) composed of at least BIRC5/survivin, CDCA8/borealin, INCENP, AURKB or AURKC; in the complex forms a triple-helix bundle-based subcomplex with INCENP and BIRC5. Interacts with SENP3, UBE2I and RANBP2. Interacts (phosphorylated) with SGO1 and SGO2; the association is dependent on CDK1 (By similarity). Localizes on chromosome arms and inner centromeres from prophase through metaphase and then transferring to the spindle midzone and midbody from anaphase through cytokinesis. The C-terminal region (aa 215-288) represents the dimerization motif. Phosphorylated by TTK, essentially at Thr-88 and Thr-94. Phosphorylation (probably by CDK1) promotes targeting of the CPC to centromeric DNA. Sumoylated by UBE2I and RANBP2. Desumoylated by SENP3 through the removal of SUMO2 and SUMO3 (By similarity). Citrullinated by PADI4. Belongs to the borealin family.