LOCATION OF GOLGI MEMBRANES WITH REFERENCE TO DIVIDING NUCLEI IN SYNCYTIAL DROSOPHILA EMBRYOS

The role of cytoskeletal elements in the cellularization of syncytial Drosophila embryos is becoming evident; however, the distribution and role of organelles such as the Golgi complex, essential for membrane b iogenesis, remain unknown. We have cloned a Golgi-membrane-associated polypeptide, beta-COP, from Drosophila. Immunocytochemical studies of syncytial Drosophila embryos with anti-Drosophila beta-COP antibody re veal that Golgi membranes are spatially segregated from the rapidly di viding nuclei. In early embryos, the Golgi membranes are located in th e embryonic cortex and nuclei are confined to the core. This distribut ion of Golgi membranes may serve in preparation of the embryonic corte x for the accommodation of nuclei upon their eventual migration to the cortex and in biogenesis of the excessive plasma membrane needed for cellularization of syncytial embryos.