Centriole and Centrosome Dynamics during the Embryonic Cell Cycles That Follow the Formation of the Cellular Blastoderm inDrosophila

• Published in: Experimental cell research 1997-07, Vol.234 (1), p.183-190
• Main Authors: Callaini, Giuliano, Whitfield, William G.F., Riparbelli, Maria Giovanna
• Format: Article
• Language: English
• ISSN: 0014-4827; 1090-2422
• DOI: 10.1006/excr.1997.3618

We have used immunofluorescence and electron microscopy to examine centrosome dynamics during the first postblastodermic mitoses in theDrosophilaembryo. The centrosomal material, as recognized by antibodies against CP190 and γ-tubulin, does not show the typical shape changes observed in syncytial embryos, but remains compact throughout mitosis. Centrioles, however, behave as during the syncytial mitoses, with each daughter cell inheriting two separated centrioles at the end of telophase. During interphase in epithelial cells that have a distinct G1 phase, two isolated centrioles are found, suggesting that the separation of sister centrioles is tightly coupled to a mitotic oscillator in both the “abbreviated” and the “complete” embryonic division cycles. The centrioles of theDrosophilaembryo sharply differed from the sperm basal body, having a cartwheel structure with nine microtubular doublets and a central tubule. This “immature” centriolar morphology was shown to persist throughout embryonic development, clearly demonstrating that these centrioles are able to replicate despite their apparently neotenic structure.