Probable plus end-directed motor protein that functions in the NACK-PQR (NPK1-NQK1/MEK1-NRK1) MAP kinase signaling pathway, which is essential for somatic cell cytokinesis, especially for the cell-plate formation and its expansion. Regulates the activity and the localization of NPK1 by association through the non-catalytic region of the kinase. Interacts (via C-terminus) with NPK1 (via C-terminus). In interphase and prophase, detected in the nucleus. From prometaphase to metaphase, found in the cytoplasm in patches. At anaphase, distributed around the spindle midzone and on the phragmoplast equator at telophase. During the M phase of the cell cycle (at protein level). Phosphorylated at Thr-145, Thr-675 and Thr-690 by CDKAs and CDKBs. The phosphorylation occurs before metaphase and inhibits the interaction with NPK1 preventing the transition to cytokinesis. Expression of a truncated protein lacking the motor domain causes inhibition of phragmoplast expansion and multinucleate cells. Belongs to the TRAFAC class myosin-kinesin ATPase superfamily. Kinesin family. KIN-7 subfamily.