Androgens promote maturation and signaling in mouse oocytes independent of transcription: A release of inhibition model for mammalian oocyte meiosis
Androgens promote maturation and signaling in mouse oocytes independent of transcription: A release of inhibition model for mammalian oocyte meiosis
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DOI：
10.1210/me.2003-0326
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发表时间：
2004-01-01
影响因子：
--
通讯作者：
Hammes, SR
中科院分区：
文献类型：
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作者：
Gill, A;Jamnongjit, M;Hammes, SR
女性的正常生育力取决于卵母细胞减数分裂的精确调节。卵母细胞在减数分裂的前期I被阻止，直到排卵之前，这时减数分裂或成熟被触发恢复。尽管性类固醇似乎可以促进鱼类和两栖动物的成熟，但调节哺乳动物卵母细胞成熟的因素仍然不清楚。我们在这里表明，类似于较低的脊椎动物，类固醇激素可能在促进哺乳动物减数分裂抑制的释放中发挥作用。具体来说，睾酮诱导小鼠卵母细胞成熟的减数分裂，以及激活MAPK和细胞周期蛋白依赖性激酶1信号。这些反应似乎是转录独立的，可能涉及通过经典的雄激素受体在卵母细胞中表达的信号。我们的研究结果是第一个表明，性类固醇可以调节哺乳动物卵母细胞减数分裂，并建议一个模型，即占主导地位的哺乳动物卵泡可能会产生足够的雄激素和/或其他类固醇，以克服组成性抑制信号，并允许卵母细胞成熟和随后的排卵发生。
Normal fertility in females depends upon precise regulation of oocyte meiosis. Oocytes are arrested in prophase I of meiosis until just before ovulation, when meiosis, or maturation, is triggered to resume. Whereas sex steroids appear to promote maturation in fish and amphibians, the factors regulating mammalian oocyte maturation have remained obscure. We show here that, similar to lower vertebrates, steroids may play a role in promoting the release of meiotic inhibition in mammals. Specifically, testosterone induced maturation of mouse oocytes arrested in meiosis, as well as activation of MAPK and cyclin-dependent kinase 1 signaling. These responses appeared to be transcription independent and might involve signaling through classical androgen receptors expressed in the oocytes. Our results are the first to show that sex steroids can modulate meiosis in mammalian oocytes and suggest a model whereby dominant ovarian follicles in mammals may produce sufficient androgen and/or other steroids to overcome constitutive inhibitory signals and allow oocyte maturation and subsequent ovulation to occur.