The Rab6-binding kinesin, Rab6-KIFL, is required for cytokinesis

The Rab6-binding kinesin, Rab6-KIFL, was identified in a two-hybrid screen for proteins that interact with Rab6, a small GTPase involved in membrane t raffic through the Golgi apparatus, We find that Rab6-KIFL accumulates in m itotic cells where it localizes to the midzone of the spindle during anapha se, and to the cleavage furrow and midbody during telophase. Overexpression of Rab6-KIFL causes a cell division defect resulting in cell death. Microi njection of antibodies to Rab6-KTFL results in the cells becoming binucleat e after one cell cycle, and time-lapse microscopy reveals that this is due to a defect in cleavage furrow formation and thus cytokinesis. These data s how that endogenous Rab6-KIFL functions in cell division during cleavage fu rrow formation and cytokinesis, in addition to its previously described rol e in membrane traffic.