Zinc Dynamics during Drosophila Oocyte Maturation and Egg Activation

• Published in: iScience Vol. 23; no. 7; p. 101275
• Main Authors: Hu, Qinan, Duncan, Francesca E., Nowakowski, Andrew B., Antipova, Olga A., Woodruff, Teresa K., O'Halloran, Thomas V., Wolfner, Mariana F.
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 24.07.2020; Elsevier
• Subjects: Biotechnology; Embryology; Evolutionary Developmental Biology; Biotechnology; Evolutionary Developmental Biology; Embryology
• ISSN: 2589-0042; 2589-0042
• DOI: 10.1016/j.isci.2020.101275

Temporal fluctuations in zinc concentration are essential signals, including during oogenesis and early embryogenesis. In mammals, zinc accumulation and release are required for oocyte maturation and egg activation, respectively. Here, we demonstrate that zinc flux occurs in Drosophila oocytes and activated eggs, and that zinc is required for female fertility. Our synchrotron-based X-ray fluorescence microscopy reveals zinc as the most abundant transition metal in Drosophila oocytes. Its levels increase during oocyte maturation, accompanied by the appearance of zinc-enriched intracellular granules in the oocyte, which depend on transporters. Subsequently, in egg activation, which mediates the transition from oocyte to embryo, oocyte zinc levels decrease significantly, as does the number of zinc-enriched granules. This pattern of zinc dynamics in Drosophila oocytes follows a similar trajectory to that in mammals, extending the parallels in female gamete processes between Drosophila and mammals and establishing Drosophila as a model for dissecting reproductive roles of zinc. [Display omitted] •Dietary zinc is required for Drosophila female fertility•Oocyte zinc levels increase over oogenesis and decrease during egg activation•Zinc is enriched in the oocyte and forms aggregated granules in mature oocytes•Transporters are required for zinc retention and zinc-enriched granules in oocytes Evolutionary Developmental Biology; Biotechnology; Embryology