College of Animal Science and Technology, Southwest University, Chongqing, 400715, China.
Department of Animal Science, Chungbuk National University, Cheongju, 28644, South Korea.
Sci Rep. 2024 Sep 19;14(1):21849. doi: 10.1038/s41598-024-73166-5.
Damage to the development of porcine gametes and embryos caused by high temperatures (HT) is one of the main reasons for the decline in the economic benefits of the livestock industry. Zygotic genome activation (ZGA) marks the beginning of gene expression programs in mammalian pre-implantation embryos. In pigs, ZGA occurs at the 4-cell (4 C) stage, indicating that correct gene expression at this stage plays an important regulatory role in embryonic development. However, the effect of the HT environment on early porcine embryonic development and the RNA expression profile of ZGA remain unclear. In this study, we compared the RNA transcription patterns of porcine 4 C embryos under normal and HT conditions using RNA-seq and identified 326 differentially expressed genes (DEGs). These changes were mainly related to DNA polymerase activity, DNA replication, and nucleotidyltransferase activity. In addition, entries for reverse transcription and endonuclease activity were enriched, indicating that ZGA interfered under HT conditions. Further comparison of the experimental results with the porcine ZGA gene revealed 39 ZGA genes among the DEGs. KEGG and GSEA analysis showed that the oxidative phosphorylation pathway was significantly enriched and signaling pathways related to energy metabolism were significantly downregulated. We also found that NDUFA6 and CDKN1A were located at the center of the protein-protein interaction network diagram of the DEGs. In summary, HT conditions affect mitochondrial function and oxidative phosphorylation levels, and lead to changes in the expression pattern of ZGA in early porcine embryos, with its hub genes NDUFA6 and CDKN1A.
高温对猪配子和胚胎发育的损伤是畜牧业经济效益下降的主要原因之一。合子基因组激活（ZGA）标志着哺乳动物着床前胚胎基因表达程序的开始。在猪中，ZGA 发生在 4 细胞（4C）阶段，表明该阶段正确的基因表达对胚胎发育起着重要的调控作用。然而，高温环境对早期猪胚胎发育的影响以及 ZGA 的 RNA 表达谱尚不清楚。在这项研究中，我们使用 RNA-seq 比较了正常和高温条件下猪 4C 胚胎的 RNA 转录模式，鉴定出 326 个差异表达基因（DEGs）。这些变化主要与 DNA 聚合酶活性、DNA 复制和核苷酸转移酶活性有关。此外，逆转录和内切酶活性的条目富集，表明 ZGA 在高温条件下受到干扰。进一步将实验结果与猪 ZGA 基因进行比较，在 DEGs 中发现了 39 个 ZGA 基因。KEGG 和 GSEA 分析表明，氧化磷酸化途径显著富集，与能量代谢相关的信号通路显著下调。我们还发现，DEGs 的蛋白质-蛋白质相互作用网络图的中心是 NDUFA6 和 CDKN1A。总之，高温条件会影响线粒体功能和氧化磷酸化水平，导致早期猪胚胎 ZGA 表达模式发生变化，其枢纽基因是 NDUFA6 和 CDKN1A。
