The Drosophila lissencephaly1 (DLis1) gene is required for nuclear migration

Nuclear movement is critical for several developmental processes in eukaryo tes. Drosophila oogenesis provides a paradigmatic example in which localiza tion of the nucleus generates a source of cellular asymmetry that is used i n patterning both the anterior-posterior and the dorsal-ventral axes of the oocyte. In this study we show that mutations in the Drosophila Lissencepha ly1 (DLis1) gene result in partial ventralization of the eggshell. DLis1 mu tations affect the localization of gurken mRNA and protein in the oocyte. T hese defects are correlated with incorrect positioning of the oocyte nucleu s, suggesting that DLis1 is required for nuclear migration. DLis1 shows sig nificant sequence conservation across the evolutionary spectrum. Fungal cog nates of DLis1 are involved in nuclear migration while homologs in humans a nd mice are implicated in neuronal migration. DLis1 shows genetic interacti ons with the Glued and Dynein heavy chain subunits of the dynein/dynactin c omplex, supporting the idea that the Lis1 family of proteins plays a role i n microtubule motor-based nuclear motility. (C) 2000 Academic Press.