Laboratorio di Biologia dello Sviluppo, Dipartimento di Biologia e Biotecnologie Lazzaro Spallanzani, Universita' degli Studi di Pavia, Pavia, Italy.
BMC Genomics. 2013 Jun 7;14:380. doi: 10.1186/1471-2164-14-380.
The cumulus cells (CCs) enveloping antral and ovulated oocytes have been regarded as putative source of non-invasive markers of the oocyte developmental competence. A number of studies have indeed observed a correlation between CCs gene expression, embryo quality, and final pregnancy outcome. Here, we isolated CCs from antral mouse oocytes of known developmental incompetence (NSN-CCs) or competence (SN-CCs) and compared their transcriptomes with the aim of identifying distinct marker transcripts.
Global gene expression analysis highlighted that both types of CCs share similar transcriptomes, with the exception of 422 genes, 97.6% of which were down-regulated in NSN-CCs vs. SN-CCs. This transcriptional down-regulation in NSN-CCs was confirmed by qRT-PCR analysis of CC-related genes (Has2, Ptx3, Tnfaip6 and Ptgs2). Only ten of the 422 genes were up-regulated with Amh being the most up-regulated in NSN-CCs, with an average 4-fold higher expression when analysed by qRT-PCR.
The developmental incompetence (NSN) or competence (SN) of antral oocytes can be predicted using transcript markers expressed by their surrounding CCs (i.e., Has2, Ptx3, Tnfaip6, Ptgs2 and Amh). Overall, the regulated nature of the group of genes brought out by whole transcriptome analysis constitutes the molecular signature of CCs associated either with developmentally incompetent or competent oocytes and may represent a valuable resource for developing new molecular tools for the assessment of oocyte quality and to further investigate the complex bi-directional interaction occurring between CCs and oocyte.
围绕着腔前卵泡和排卵卵母细胞的卵丘细胞（CCs）一直被认为是卵母细胞发育能力的非侵入性标志物的潜在来源。事实上，许多研究已经观察到 CCs 基因表达、胚胎质量和最终妊娠结局之间存在相关性。在这里，我们从已知发育能力不足（NSN-CCs）或有能力（SN-CCs）的腔前卵泡小鼠卵母细胞中分离 CCs，并比较它们的转录组，旨在鉴定出不同的标记转录本。
全基因表达分析突出表明，两种类型的 CCs 具有相似的转录组，除了 422 个基因，其中 97.6%在 NSN-CCs 中下调与 SN-CCs。通过对 CC 相关基因（Has2、Ptx3、Tnfaip6 和 Ptgs2）的 qRT-PCR 分析，证实了 NSN-CCs 中的这种转录下调。在 422 个基因中，只有 10 个上调，其中 NSN-CCs 中 Amh 上调最明显，qRT-PCR 分析显示其表达水平平均高出 4 倍。
可以使用周围 CCs 表达的转录标记物来预测腔前卵泡卵母细胞的发育能力（即 Has2、Ptx3、Tnfaip6、Ptgs2 和 Amh）。总体而言，全转录组分析中所涉及的基因的调节性质构成了与发育能力不足或有能力的卵母细胞相关的 CCs 的分子特征，并且可能代表了开发用于评估卵母细胞质量的新分子工具和进一步研究 CCs 与卵母细胞之间复杂双向相互作用的有价值资源。
