Plus-end directed kinesin-like motor enzyme involved in mitotic spindle assembly. Required for centrosome separation and maintenance of spindle bipolarity during mitosis (By similarity). Homodimer. Dimerization is required for targeting to microtubule minus ends. Found in a complex with tpx2 and microtubules. Its association with microtubules and targeting to microtubule minus ends requires tpx2 (By similarity). Localizes during metaphase on spindle microtubules, with a strong enrichment at spindle poles. Localizes to the minus ends of spindle pole and aster microtubules in a dynein- and dynactin-dependent manner. Detected diffusively in the cytoplasm. Localized at the centrosome during the interphase and throughout mitosis (By similarity). Strongly expressed in testis and weakly in lung (at protein level). Expressed maternally in oocytes and eggs (at protein level). Belongs to the TRAFAC class myosin-kinesin ATPase superfamily. Kinesin family. KLP2 subfamily. Potential poly-A sequence.