Zinc Availability Regulates Exit from Meiosis in Maturing Mammalian Oocytes
نویسندگان
چکیده
Cellular metal ion fluxes are known in alkali and alkaline earth metals but are not well documented in transition metals. Here we describe major changes in the zinc physiology of the mammalian oocyte as it matures and initiates embryonic development. Single-cell elemental analysis of mouse oocytes by synchrotron-based X-ray fluorescence microscopy (XFM) revealed a 50% increase in total zinc content within the 12-14-h period of meiotic maturation. Perturbation of zinc homeostasis with a cell-permeable small-molecule chelator blocked meiotic progression past telophase I. Zinc supplementation rescued this phenotype when administered before this meiotic block. However, after telophase arrest, zinc triggered parthenogenesis, suggesting that exit from this meiotic step is tightly regulated by the availability of a zinc-dependent signal. These results implicate the zinc bolus acquired during meiotic maturation as an important part of the maternal legacy to the embryo.
منابع مشابه
Zinc Availability Regulates Exit from Meiosis in Maturing Mammalian Oocytes Perturbation of Intracellular Zinc Disrupts Asymmetric Division
I ron, copper and zinc are three of the most abundant transition metals in biology and are essential components of most cells 1–3. They play many well-established roles as structural and catalytic components of a myriad of proteins and may also have intracellular signaling functions 4,5 akin to those performed by the alkaline earth metal calcium. The intracellular availability of these transiti...
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