DROSOPHILA CENTROSOMIN PROTEIN IS REQUIRED FOR MALE MEIOSIS AND ASSEMBLY OF THE FLAGELLAR AXONEME

Centrosomes and microtubules play crucial roles during cell division a nd differentiation. Spermatogenesis is a useful system for studying ce ntrosomal function since it involves both mitosis and meiosis, and als o transformation of the centriole into the sperm basal body. Centrosom in is a protein localized to the mitotic centrosomes in Drosophila mel anogaster. We have found a novel isoform of centrosomin expressed duri ng spermatogenesis. Additionally, an anticentrosomin antibody labels b oth the mitotic and meiotic centrosomes as well as the basal body. Mut ational analysis shows that centrosomin is required for spindle organi zation during meiosis and for organization of the sperm axoneme, These results suggest that centrosomin is a necessary component of the meio tic centrosomes and the spermatid basal body.