Promotes ATP-dependent removal of tubulin dimers from microtubules. Regulates the turnover of microtubules at the kinetochore and functions in chromosome segregation during mitosis (PubMed:8548824). May play a role in chromosome congression and may be required for the lateral to end-on conversion of the chromosome-microtubule attachment (By similarity). Belongs to the TRAFAC class myosin-kinesin ATPase superfamily. Kinesin family. MCAK/KIF2 subfamily.