Regulates centrosome duplication and mitotic spindle dynamics (PubMed:20230755, PubMed:31907206). Also involved in controlling the size of dendritic arbors (PubMed:24643112). May act as co-chaperone for Hsp83 (PubMed:31907206). During mitotic spindle assembly, regulates microtubule (MT) dynamics by binding to MTs and promoting MT polymerisation (PubMed:31907206). Promotes the elongation and retraction of terminal branches in response to changes in body size, possibly acting downstream of the TORC2 pathway to enable proportional scaling of dendritic arbors (PubMed:24643112). Interacts with Hsp83. In syncytial embryos, mostly cytoplasmic during interphase, with enrichment in the perinuclear area and a weak nuclear localization. Upon nuclear envelope breakdown, localizes to the spindles and remains associated with the spindle microtubules throughout mitosis. Expressed in embryos (PubMed:31907206). Expressed in larvae (PubMed:24643112). Results in centrosome amplification and lethality (PubMed:20230755). Cells become polyploid or undergo apoptosis (PubMed:20230755). Homozygotes died as third instar larvae (PubMed:20230755). RNAi-mediated knockdown in neuronal cells, results in severe mitotic defects in the larval brain and is lethal at the third-instar stage (PubMed:31907206). RNAi-mediated knockdown in the female germline, results in embryos failing to hatch due to various mitotic defects such as abnormal chromosome condensation and adherent spindle formation (PubMed:31907206). However, in contrast to RNAi-mediated knockdown in the brain, embryos do not exhibit centrosome amplification (PubMed:31907206).