earticle

영어

Zinc (Zn2+) is one of essential factors during mammalian oocyte maturation and fertilization. Previous studies showed that depletion of cellular Zn by metalion chelator impair asymmetric division of oocyte. But the detailed mechanism of these phenomena is unclear. We found that depletions of zinc by cell-permeable heavy metal chelator N,N,N',N'- tetrakis(2-pyridylmethyl)ethane-1,2-diamine (TPEN) caused the decrease of cytoplasmic actin mesh level. Spire2-GFP is co-localized with zinc at the cortex and intracellular vesicle. By the treatment of TPEN, number of Spire2-GFP decorated vesicle is drastically decreased, indicating that Zn2+ is essential for the localization of the spire in mouse oocyte. Two putative zinc-binding regions were located in the C-terminal part of Spire2. Mutations of zinc binding site on spire abolish its localization at the intracellular vesicle. Over expression of C-terminal region containing zinc binding site of spire impair oocyte maturations and decrease cytoplasmic actin mesh. Taken together, these results suggest that intracellular zinc is crucial for the proper localizations of spire in the mouse oocyte, and unraveling the novel regulatory mode of actin nucleator spire by Zn2+.