Microtubule motor protein that binds to microtubules with high affinity through each tubulin heterodimer and has an ATPase activity (By similarity). Plays a role in many processes like cell division; cytokinesis and also in cell proliferation and apoptosis (PubMed:24784001; PubMed:16648480). During cytokinesis; targets to central spindle and midbody through its interaction with PRC1 and CIT respectively (PubMed:16431929). Regulates cell growth through regulation of cell cycle progression and cytokinesis (PubMed:24854087). During cell cycle progression acts through SCF-dependent proteasomal ubiquitin-dependent protein catabolic process which controls CDKN1B degradation; resulting in positive regulation of cyclins; including CCNE1; CCND1 and CCNB1 (PubMed:24854087). During late neurogenesis; regulates the cerebellar; cerebral cortex and olfactory bulb development through regulation of apoptosis; cell proliferation and cell division (By similarity). Also is required for chromosome congression and alignment during mitotic cell cycle process (PubMed:15843429). Regulates cell spreading; focal adhesion dynamics; and cell migration through its interaction with RADIL resulting in regulation of RAP1A-mediated inside-out integrin activation by tethering RADIL on microtubules (PubMed:23209302). {ECO:0000250|UniProtKB:L0N7N1; ECO:0000269|PubMed:15843429; ECO:0000269|PubMed:16431929; ECO:0000269|PubMed:16648480; ECO:0000269|PubMed:23209302; ECO:0000269|PubMed:24784001; ECO:0000269|PubMed:24854087}.