title: Meiotic spindle organization in fertilized Drosophila oocyte: presence of centrosomal components in the meiotic apparatus.
abstract: We examined spindle reorganization during the completion of meiosis in fertilized and unfertilized oocytes of Drosophila using indirect immunofluorescence and laser scanning confocal microscopy. The results defined a complex pathway of spindle assembly during resumption of meiosis, and revealed a transient array of microtubules radiating from the equatorial region of the spindle towards discrete foci in the egg cortex. A monastral array of microtubules was observed between twin metaphase II spindles in fertilized and unfertilized eggs. The microtubules originated from disk-shaped material stained with Rb188 antibody specific for an antigen associated with the centrosome of Drosophila embryos. The Drosophila egg, therefore, contains a maternal pool of centrosomal components undetectable in mature inactivated oocytes. These components nucleate microtubules in a monastral array after activation, but are unable to organize bipolar spindles.
authors: Department of Evolutionary Biology, University of Siena, Italy.
authors: M G
authors: MG
authors: Riparbelli
authors: G
authors: G
authors: Callaini
mesh_terms: D000818:Animals; D018385:Centrosome / Q000648:ultrastructure*; D004331:Drosophila melanogaster / Q000235:genetics*; D005306:Fertilization; D008297:Male; D008540:Meiosis / Q000235:genetics*; D009865:Oocytes / Q000648:ultrastructure*; D013094:Spermatozoa / Q000502:physiology; D008941:Spindle Apparatus