Studies for molecular mechanism of meiotic-competence-acquisition in porcine growing oocytes

哺乳动物生长中的卵母细胞不能恢复cdc2活性介导的减数分裂成熟，即使它们生长到最终大小的90%。本研究以猪卵母细胞为研究对象，分析了这一缺陷的分子机制。结果表明，生长中的猪卵母细胞的减数分裂成熟受到两种机制的抑制，一种是CDC2数量不足，另一种是通过调节PKA定位抑制CDC2的激活。此外，PKA调控亚单位（PKA- rs）和A激酶锚定蛋白（AKAPs）参与PKA定位的控制，在完全发育和生长的卵母细胞之间存在差异。本研究为卵母细胞生长过程中PKA调控机制的改变是哺乳动物卵母细胞获得减数分裂能力的原理提供了新的认识。

Mammalian growing oocytes cannot resume CDC2-activity-mediated meiotic maturation, even if they are grown up to 90% of their final size. In the present study, the molecular mechanisms of this incompetence were analyzed using porcine oocytes.As the results, it was revealed that porcine growing oocytes was inhibited their meiotic maturation by the two mechanisms, one was the insufficient CDC2 amount and the another one was the suppression of CDC2 activation by the regulation of PKA localization. In addition, the differences of PKA regulatory subunits (PKA-Rs) and A kinase anchoring proteins (AKAPs), which were involved in the control of PKA localization, were suggested between fully-grown and growing oocytes. I provided new insight that the change of PKA regulation mechanism during oocyte growth phase was the principle for the acquisition of meiotic competence in mammalian growing oocytes.