Tokumoto T, Tokumoto M, Seto K, Horiguchi R, Nagahama Y, Yamada S, Ishikawa K, Lohka M J
Faculty of Science, Shizuoka University, Shizuoka, 422-8529, Japan.
Exp Cell Res. 1999 Mar 15;247(2):313-9. doi: 10.1006/excr.1998.4357.
We have prepared polyclonal antibodies against Xenopus 20S proteasomes. The antibodies cross-react with several proteins that are common to 20S and 26S proteasomes and with at least two proteins that are unique to 26S proteasomes. The antibodies were used to analyze changes in the components of proteasomes during oocyte maturation and early development of Xenopus laevis. A novel protein with a molecular weight of 48 kDa, p48, was clearly detected in immature oocytes, but was found at very low levels in mature oocytes and ovulated eggs. p48 was reduced to low levels during oocyte maturation, after maturation-promoting factor was activated. The amount of p48 in eggs remained low during early embryonic development, but increased again after the midblastula transition. These results show that at least one component of 26S proteasomes changes during oocyte maturation and early development and suggest that alterations in proteasome function may be important for the regulation of developmental events, such as the rapid cell cycles, of the early embryo.
我们制备了针对非洲爪蟾20S蛋白酶体的多克隆抗体。这些抗体与20S和26S蛋白酶体共有的几种蛋白质发生交叉反应，并与至少两种26S蛋白酶体特有的蛋白质发生交叉反应。这些抗体被用于分析非洲爪蟾卵母细胞成熟和早期发育过程中蛋白酶体成分的变化。在未成熟卵母细胞中清晰检测到一种分子量为48 kDa的新蛋白质p48，但在成熟卵母细胞和排卵卵中含量极低。在促成熟因子激活后，卵母细胞成熟过程中p48水平降低。在早期胚胎发育过程中，卵中p48的含量一直很低，但在囊胚中期转变后又再次升高。这些结果表明，26S蛋白酶体的至少一种成分在卵母细胞成熟和早期发育过程中发生变化，并提示蛋白酶体功能的改变可能对早期胚胎发育事件（如快速细胞周期）的调节很重要。
