Lis1, the Drosophila homolog of a human lissencephaly disease gene, is required for germline cell division and oocyte differentiation

Lissencephaly is a severe congenital brain malformation resulting from inco mplete neuronal migration. One causal gene, LIS1, is homologous to nudF, a gene required for nuclear migration in A. nidulans. We have characterized t he Drosophila homolog of LIS1 (Lis1) and show that Lis1 is essential for Ay development. Analysis of ovarian Lis1 mutant clones demonstrates that Lis1 is required in the germline for synchronized germline cell division, fusom e integrity and oocyte differentiation. Abnormal packaging of the cysts was observed in Lis1 mutant clones. Our results indicate that LIS1 is importan t for cell division and differentiation and the function of the membrane cy toskeleton. They support the notion that LIS1 functions with the dynein com plex to regulate nuclear migration or cell migration.