Location of Golgi membranes with reference to dividing nuclei in syncytial Drosophila embryos.

The role of cytoskeletal elements in thecellularization of syncytial Drosophila embryos is becoming evident; however,the distribution and role of organelles such as the Golgi complex, essential formembrane biogenesis, remain unknown. We have cloned a Golgi-membrane-associatedpolypeptide, beta-COP, from Drosophila. Immunocytochemical studies of syncytialDrosophila embryos with anti-Drosophila beta-COP antibody reveal that Golgimembranes are spatially segregated from the rapidly dividing nuclei. In earlyembryos, the Golgi membranes are located in the embryonic cortex and nuclei areconfined to the core. This distribution of Golgi membranes may serve inpreparation of the embryonic cortex for the accommodation of nuclei upon theireventual migration to the cortex and in biogenesis of the excessive plasmamembrane needed for cellularization of syncytial embryos.