Akt expression in mouse oocytes matured in vivo and in vitro
Akt expression in mouse oocytes matured in vivo and in vitro
复制标题
DOI：
10.1016/j.rbmo.2009.10.011
复制
发表时间：
2010-01-01
影响因子：
4
通讯作者：
Macchiarelli, Guido
中科院分区：
文献类型：
--
作者：
Cecconi, Sandra;Rossi, Gianna;Macchiarelli, Guido
为了提高体外成熟卵母细胞的发育能力，可以在培养液中添加次黄嘌呤(HX)和卵泡刺激素(FSH)或表皮生长因子(EGF)，以激活调控减数分裂恢复和进展的必要信号通路。由于丝氨酸/苏氨酸激酶Akt参与了减数分裂细胞周期的调节，本研究分析了在体内或体外成熟的卵母细胞中，在HX-FSH或HX-EGF存在下，Akt在减数分裂纺锤体中的表达水平和定位。与所采用的培养条件无关，Akt mRNA的浓度从生发泡到中期I(MI)没有变化，在MII时白色。体内成熟的卵母细胞和HX-EGF刺激的卵母细胞Akt1 mRNA浓度显著降低(P<；0.05)。不同MI组卵母细胞的光短化Akt蛋白含量相似，但体内成熟卵母细胞和体外成熟的HX-EGF卵母细胞在MII期光短化Akt蛋白含量均降低。Ser-473磷酸化Akt在90%以上的卵母细胞中均定位于减数分裂纺锤体。这些结果表明，在小鼠卵母细胞中，Akt的表达在体内和体外成熟过程中受到不同的调节，提示EGF可能是卵母细胞减数分裂成熟的正向调节因子，甚至比FSH更强。(C)2009，爱思唯尔有限公司出版。版权所有。
To improve developmental competence of in vitro matured oocytes, culture medium can be supplemented with hypoxanthine (Hx) and FSH or epidermal growth factor (EGF) to trigger the activation of essential signalling pathways regulating meiotic resumption and progression. Since the serine/threonine kinase, Akt, contributes to the regulation of the meiotic cell cycle, this study analysed its expression level and localization at the meiotic spindle in oocytes matured in vivo or in vitro in the presence of Hx-FSH or Hx-EGF. Independently of culture conditions adopted, Akt mRNA concentration did not vary from germinal vesicle to metaphase I (MI), white at MII a significant decrease in Akt1 mRNA concentration was recorded in oocytes matured in vivo and in those stimulated by Hx-EGF (P < 0.05). Phoshorylated Akt protein content was similar in the different groups of MI oocytes, but it decreased at MII in oocytes matured either in vivo or in vitro with Hx-EGF. Ser-473-phosphorytated Akt was localized uniformly to the meiotic spindle in more than 90% of oocytes. These results indicate that, in mouse oocytes, Akt expression is differentially regulated during in vivo and in vitro maturation and suggest that EGF could be a positive modulator, even stronger than FSH, of oocyte meiotic maturation. (C) 2009, Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.