The transition from a transcriptionally active state (GV) to a transcriptionally inactive state (mature MII oocytes) is required for the acquisition of oocyte developmental competence. We hypothesize that the expression of specific genes at the in vivo matured (MII) stage could be modulated by posttranscriptional mechanisms, particularly regulation of alternative splicing (AS). In this study, we examined the transcriptional activity of GV oocytes after ovarian stimulation followed by oocyte pick-up and the landscape of alternatively spliced isoforms in human MII oocytes. Individual oocytes were processed and analyzed for transcriptional activity (GV), gene expression (GV and MII), and AS signatures (GV and MII) on HTA 2.0 microarrays. Samples were grouped according to maturation stage, and then subgrouped according to women's age and antral follicular count (AFC); array results were validated by quantitative polymerase chain reaction. Differentially expressed genes between GV and MII oocytes clustered mainly in biological processes related to mitochondrial metabolism. Interestingly, 16 genes that were related to the regulation of transcription and mitochondrial translation showed differences in alternatively spliced isoform profiles despite not being differentially expressed between groups. Altogether, our results contribute to our understanding of the role of AS in oocyte developmental competence acquisition.

中文翻译：

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人类卵母细胞减数分裂成熟与可变剪接转录亚型的特定特征有关

从转录活性状态 (GV) 到转录非活性状态（成熟的 MII 卵母细胞）的转变是获得卵母细胞发育能力所必需的。我们假设体内成熟（MII）阶段特定基因的表达可以通过转录后机制进行调节，特别是选择性剪接（AS）的调节。在这项研究中，我们检查了 GV 卵母细胞在卵巢刺激后取卵后的转录活性，以及​​人类 MII 卵母细胞中可变剪接同种型的景观。在 HTA 2.0 微阵列上处理和分析单个卵母细胞的转录活性 (GV)、基因表达 (GV 和 MII) 和 AS 特征 (GV 和 MII)。样本根据成熟阶段分组，然后根据女性的亚组 s 年龄和窦卵泡计数 (AFC)；阵列结果通过定量聚合酶链反应进行验证。GV和MII卵母细胞之间差异表达的基因主要聚集在与线粒体代谢相关的生物过程中。有趣的是，尽管在组间没有差异表达，但与转录和线粒体翻译调控相关的 16 个基因在可变剪接异构体谱中显示出差异。总之，我们的结果有助于我们理解 AS 在卵母细胞发育能力获得中的作用。尽管在组间没有差异表达，但与转录和线粒体翻译调控相关的 16 个基因在可变剪接异构体谱中显示出差异。总之，我们的结果有助于我们理解 AS 在卵母细胞发育能力获得中的作用。尽管在组间没有差异表达，但与转录和线粒体翻译调控相关的 16 个基因在可变剪接异构体谱中显示出差异。总之，我们的结果有助于我们理解 AS 在卵母细胞发育能力获得中的作用。