College of Animal Science and Technology, Nanjing Agricultural University, Nanjing 210095, China.
College of Animal Science and Technology, Nanjing Agricultural University, Nanjing 210095, China.
Biochim Biophys Acta Mol Cell Res. 2018 Feb;1865(2):455-462. doi: 10.1016/j.bbamcr.2017.11.016. Epub 2017 Dec 6.
Arf6 (ADP-ribosylation factor 6) is known to play important roles in membrane dynamics through the regulation of actin filament reorganization for multiple cellular processes such as cytokinesis, phagocytosis, cell migration and tumor cell invasion. However, the functions of Arf6 in mammalian oocyte meiosis have not been clarified. In present study we showed that Arf6 expressed in mouse oocytes and was mainly distributed around the spindle during meiosis. Depletion of Arf6 by morpholino microinjection caused oocytes failing to extrude first polar body. Further analysis indicated that Arf6 knock down caused the aberrant actin distribution, which further induced the failure of meiotic spindle movement. And the loss of oocyte polarity also confirmed this. The regulation of Arf6 on actin filaments in mouse oocytes might be due to its effects on the phosphorylation level of cofilin and the expression of Arp2/3 complex. Moreover, we found that the decrease of Arf6 caused the disruption of spindle formation, indicating the multiple roles of Arf6 on cytoskeleton dynamics in meiosis. In summary, our results indicated that Arf6 was involved in mouse oocyte meiosis through its functional roles in actin-mediated spindle movement and spindle organization.
Arf6（ADP-ribosylation factor 6）通过调节肌动蛋白丝重组，在细胞分裂、吞噬作用、细胞迁移和肿瘤细胞侵袭等多种细胞过程中发挥重要作用。然而，Arf6 在哺乳动物卵母细胞减数分裂中的功能尚未阐明。本研究表明，Arf6 在小鼠卵母细胞中表达，在减数分裂过程中主要分布在纺锤体周围。用 morpholino 显微注射耗尽 Arf6 会导致卵母细胞无法排出第一极体。进一步分析表明，Arf6 敲低导致肌动蛋白分布异常，进而导致减数分裂纺锤体运动失败。卵母细胞极性的丧失也证实了这一点。Arf6 对小鼠卵母细胞中肌动蛋白丝的调节可能与其对丝切蛋白磷酸化水平和 Arp2/3 复合物表达的影响有关。此外，我们发现 Arf6 的减少导致纺锤体形成的破坏，表明 Arf6 在减数分裂细胞骨架动力学中具有多种作用。总之，我们的结果表明，Arf6 通过其在肌动蛋白介导的纺锤体运动和纺锤体组织中的功能作用参与了小鼠卵母细胞减数分裂。
