A CHROMATIN-ASSOCIATED KINESIN-RELATED PROTEIN REQUIRED FOR NORMAL MITOTIC CHROMOSOME SEGREGATION IN DROSOPHILA

The tiovivo (tie) gene of Drosophila encodes a kinesin-related protein , KLP38B, that colocalizes with condensed chromatin during cell divisi on. Wild-type function of the tio gene product KLP38B is required for normal chromosome segregation during mitosis. Mitotic cells in tio lar val brains displayed circular mitotic figures, increased ploidy, and a bnormal anaphase figures, KLP38B mRNA is maternally provided and expre ssed in cells about to undergo division. We propose that KLP38B, perha ps redundantly with other chromosome-associated microtubule motor prot eins, contributes to interactions between chromosome arms and microtub ules important for establishing bipolar attachment of chromosomes and assembly of stable bipolar spindles.