PATHWAYS OF SPINDLE FORMATION IN DROSOPHILA MITOTIC AND MEIOTIC CELLS

Spindle assembly relies on three main classes of microtubules (MTs): MTs nucleated by the centrosomes, MTs nucleated near the chromosomes/kinetochores and MTs nucleated from preexisting MTs through the augmin-based pathway. Here, we review the roles of these microtubule generation pathways in Drosophila spindle assembly. The extant results indicate that female meiotic cells, male meiotic cells, larval brain cells and S2 tissue culture cells exploit specific pathway combinations for generating the MTs necessary for spindle formation. Thus, different Drosophila cell types have specific modes of spindle assembly, which might be related to specific functional and developmental requirements.