SummaryOxygen concentration influences oocyte quality and subsequent embryo development, but it remains unclear whether oxygen concentrations affect the developmental competence and transcriptomic profile of yak oocytes. In this study, we investigated the effects of different oxygen concentrations (5% versus 20%) on the developmental competence, reactive oxygen species (ROS) levels, glutathione (GSH) content, and transcriptomic profile of yak oocytes. The results showed that a low oxygen concentration significantly increased the maturation rate of yak oocytes (81.2 ± 2.2% vs 75.9 ± 1.3%) and the blastocyst quality of yak in vitro fertilized embryos. Analysis of ROS and GSH showed that a low oxygen concentration reduced ROS levels and increased the content of GSH (75.05 ± 7.1 ng/oocyte vs 50.63 ± 5.6 ng/oocyte). Furthermore, transcriptomic analysis identified 120 differentially expressed genes (DEGs) between the two groups of oocytes. Gene enrichment analysis of the DEGs indicated multiple cellular processes, including oxidative phosphorylation, transcription regulation, mitochondrial regulation, oestrogen signalling pathway, HIF-1 signalling pathway, TNF signalling pathway, were involved in the response to oxygen concentration alterations. Taken together, these results indicated that a low oxygen concentration improved the developmental competence of yak oocytes.

中文翻译：

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氧浓度对牦牛卵母细胞发育能力和转录组谱的影响

摘要氧浓度影响卵母细胞质量和随后的胚胎发育，但尚不清楚氧浓度是否会影响牦牛卵母细胞的发育能力和转录组学特征。在这项研究中，我们研究了不同氧气浓度（5% 对 20%）对牦牛卵母细胞发育能力、活性氧 (ROS) 水平、谷胱甘肽 (GSH) 含量和转录组谱的影响。结果表明，低氧浓度显着提高了牦牛卵母细胞的成熟率（81.2±2.2% vs 75.9±1.3%）和牦牛的囊胚质量。体外受精的胚胎。对 ROS 和 GSH 的分析表明，低氧浓度降低了 ROS 水平并增加了 GSH 的含量（75.05 ± 7.1 ng/卵母细胞对 50.63 ± 5.6 ng/卵母细胞）。此外，转录组分析确定了两组卵母细胞之间的 120 个差异表达基因 (DEG)。DEGs的基因富集分析表明，氧化磷酸化、转录调控、线粒体调控、雌激素信号通路、HIF-1信号通路、TNF信号通路等多个细胞过程参与了对氧浓度变化的反应。总之，这些结果表明低氧浓度提高了牦牛卵母细胞的发育能力。