Multitasking protein that has dual roles in promoting cell proliferation and preventing apoptosis (  ). Component of a chromosome passage protein complex (CPC) which is essential for chromosome alignment and segregation during mitosis and cytokinesis . Acts as an important regulator of the localization of this complex; directs CPC movement to different locations from the inner centromere during prometaphase to midbody during cytokinesis and participates in the organization of the center spindle by associating with polymerized microtubules . Involved in the recruitment of CPC to centromeres during early mitosis via association with histone H3 phosphorylated at 'Thr-3' (H3pT3) during mitosis . The complex with RAN plays a role in mitotic spindle formation by serving as a physical scaffold to help deliver the RAN effector molecule TPX2 to microtubules . May counteract a default induction of apoptosis in G2/M phase . The acetylated form represses STAT3 transactivation of target gene promoters . May play a role in neoplasia . Inhibitor of CASP3 and CASP7 . Essential for the maintenance of mitochondrial integrity and function . Isoform 2 and isoform 3 do not appear to play vital roles in mitosis (, ). Isoform 3 shows a marked reduction in its anti-apoptotic effects when compared with the displayed wild-type isoform .
Subcellular locations: Cytoplasm, Nucleus, Chromosome, Chromosome, Centromere, Cytoplasm, Cytoskeleton, Spindle, Chromosome, Centromere, Kinetochore, Midbody
Localizes at the centromeres from prophase to metaphase, at the spindle midzone during anaphase and a the midbody during telophase and cytokinesis. Accumulates in the nucleus upon treatment with leptomycin B (LMB), a XPO1/CRM1 nuclear export inhibitor (By similarity). Localizes on chromosome arms and inner centromeres from prophase through metaphase. Localizes to kinetochores in metaphase, distributes to the midzone microtubules in anaphase and at telophase, localizes exclusively to the midbody . Colocalizes with AURKB at mitotic chromosomes . Acetylation at Lys-129 directs its localization to the nucleus by enhancing homodimerization and thereby inhibiting XPO1/CRM1-mediated nuclear export .
Expressed only in fetal kidney and liver, and to lesser extent, lung and brain . Abundantly expressed in adenocarcinoma (lung, pancreas, colon, breast, and prostate) and in high-grade lymphomas (, ). Also expressed in various renal cell carcinoma cell lines . Expressed in cochlea including the organ of Corti, the lateral wall, the interdental cells of the Limbus as well as in Schwann cells and cells of the cochlear nerve and the spiral ganglions (at protein level). Not expressed in cells of the inner and outer sulcus or the Reissner's membrane (at protein level) (, ).