Minus end-directed microtubule-dependent motor required for bipolar spindle formation (PubMed:16638812). May contribute to movement of early endocytic vesicles (PubMed:17360972). Regulates cilium formation and structure (PubMed:23807208). Binds NUBP1 and NUBP2 (PubMed:16638812). Interacts with PPP1R42 (PubMed:18237440). Associated with nucleus during interphase, centrosomes in early and spindle in later mitosis. Highly expressed in 14 dpc embryos, spleen and NIH3T3 cells. Also expressed in testis, brain, lung, kidney and cultured astrocytes. Very low levels in skeletal muscle and heart. Highly expressed in hippocampus of 13 dpc embryos declining to low levels by 18 dpc and to undetectable levels in juvenile and adult hippocampus. Centrosome amplification as well as multipolar spindles. Cells overexpressing Kifc1 show a single microtubule aster and growth arrest in prometaphase. Purified early endocytic vesicles bind minus end-directed Kifc1 as well as plus end-directed Kif5b. Addition of anti-Kifc1 antibodies leads to a decrease in minus end-directed vesicle motility in vitro. Belongs to the TRAFAC class myosin-kinesin ATPase superfamily. Kinesin family. NCD subfamily.