Tokmakov Alexander A, Sato Ken-Ichi
Faculty of Biology-Oriented Science and Technology, KinDai University, 930 Nishimitani, Kinokawa City 649-6493, Japan.
Faculty of Life Sciences, Kyoto Sangyo University, Kamigamo-Motoyama, Kita-ku, Kyoto 603-8555, Japan.
Int J Mol Sci. 2025 Apr 27;26(9):4163. doi: 10.3390/ijms26094163.
In many vertebrates, mature ovulated eggs are arrested at metaphase II prior to fertilization. The eggs exit meiotic arrest after fertilization-induced or parthenogenetic activation, followed by embryo development or egg degradation, respectively. Calcium-dependent activation of meiotically-arrested eggs has been thoroughly investigated in various species. In addition, several recent studies have detailed the excessive activation of ovulated frog eggs, so-called overactivation. This overview highlights the major events of overactivation observed in mature ovulated eggs of the African clawed frog with a focus on similarities and differences between spontaneous, oxidative stress-induced, and mechanical stress-induced overactivation. The dramatically different cell death scenarios that unfold in activated and overactivated eggs are also exposed in the article.
在许多脊椎动物中，成熟的排卵卵在受精前停滞于减数分裂中期II。受精诱导或孤雌生殖激活后，卵母细胞退出减数分裂停滞，随后分别进行胚胎发育或卵母细胞降解。减数分裂停滞的卵母细胞的钙依赖性激活已在各种物种中得到深入研究。此外，最近的几项研究详细描述了排卵蛙卵的过度激活，即所谓的超激活。本综述重点介绍了在非洲爪蟾成熟排卵卵中观察到的超激活的主要事件，重点关注自发、氧化应激诱导和机械应激诱导的超激活之间的异同。文章还揭示了激活和过度激活的卵母细胞中截然不同的细胞死亡情况。
