Meiotic chromosome distribution in Drosophila oocytes: roles of two kinesin-related proteins.

Recent new information regarding the proteins required for proper distribution of chromosomes in meiosis has come from studies of Drosophila mutants. These studies reveal that proteins related to the microtubule motor protein, kinesin, function in meiotic chromosome segregation in Drosophila females. The two proteins identified thus far are likely to play very different roles in the process. The ncd protein is a spindle motor in meiosis but may perform a different role in the early mitotic divisions of the embryo. nod functions earlier in meiosis than ncd, prior to the meiotic divisions, and may be either chromosome or spindle associated. The identification of nod as a kinesin protein raises new questions regarding the distributive model of meiotic chromosome segregation.