Although our knowledge regarding oocyte quality and development has improved significantly, the molecular mechanisms that regulate and determine oocyte developmental competence are still unclear. Therefore, the objective of this study was to identify and analyze the transcriptome profiles of porcine oocytes derived from large or small follicles using RNA high-throughput sequencing technology. RNA libraries were constructed from oocytes of large (LO; 3-6 mm) or small (SO; 1.5-1.9 mm) ovarian follicles and then sequenced in an Illumina HiSeq4000. Transcriptome analysis showed a total of 14,557 genes were commonly detected in both oocyte groups. Genes related to the cell cycle, oocyte meiosis, and quality were among the top highly expressed genes in both groups. Differential expression analysis revealed 60 up- and 262 downregulated genes in the LO compared with the SO group. BRCA2, GPLD1, ZP3, ND3, and ND4L were among the highly abundant and highly significant differentially expressed genes (DEGs). The ontological classification of DEGs indicated that protein processing in endoplasmic reticulum was the top enriched pathway. In addition, biological processes related to cell growth and signaling, gene expression regulations, cytoskeleton, and extracellular matrix organization were among the highly enriched processes. In conclusion, this study provides new insights into the global transcriptome changes and the abundance of specific transcripts in porcine oocytes in correlation with follicle size.

中文翻译：

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猪卵母细胞的整体转录组分析与卵泡大小相关。

尽管我们对卵母细胞质量和发育的了解已大大提高，但调节和确定卵母细胞发育能力的分子机制仍不清楚。因此，本研究的目的是使用RNA高通量测序技术鉴定和分析来自大卵泡或小卵泡的猪卵母细胞的转录组谱。从大卵泡（LO; 3-6 mm）或小卵泡（SO; 1.5-1.9 mm）的卵母细胞构建RNA文库，然后在Illumina HiSeq4000中测序。转录组分析显示，在两个卵母细胞组中通常共检测到14,557个基因。与细胞周期，卵母细胞减数分裂和质量相关的基因是两组中表达最强的基因之一。差异表达分析显示，与SO组相比，LO中有60个上调基因和262个下调基因。BRCA2，GPLD1，ZP3，ND3和ND4L属于高度丰富且高度重要的差异表达基因（DEG）。DEG的本体分类表明，内质网中的蛋白质加工是最富集的途径。此外，与细胞生长和信号传导，基因表达调控，细胞骨架和细胞外基质组织有关的生物学过程也是高度丰富的过程。总之，这项研究为猪卵母细胞中与卵泡大小相关的整体转录组变化和特定转录本的丰富性提供了新的见解。ND4L和ND4L是高度丰富和高度重要的差异表达基因（DEG）之一。DEG的本体分类表明，内质网中的蛋白质加工是最富集的途径。此外，与细胞生长和信号传导，基因表达调控，细胞骨架和细胞外基质组织有关的生物学过程也是高度丰富的过程。总之，这项研究为猪卵母细胞中与卵泡大小相关的整体转录组变化和特定转录本的丰富性提供了新的见解。ND4L和ND4L是高度丰富和高度重要的差异表达基因（DEG）之一。DEG的本体分类表明，内质网中的蛋白质加工是最富集的途径。此外，与细胞生长和信号传导，基因表达调控，细胞骨架和细胞外基质组织有关的生物学过程也是高度丰富的过程。总之，这项研究为猪卵母细胞中与卵泡大小相关的整体转录组变化和特定转录本的丰富性提供了新的见解。基因表达调控，细胞骨架和细胞外基质组织是高度富集的过程。总之，这项研究为猪卵母细胞中与卵泡大小相关的整体转录组变化和特定转录本的丰富性提供了新的见解。基因表达调控，细胞骨架和细胞外基质组织是高度富集的过程。总之，这项研究为猪卵母细胞中与卵泡大小相关的整体转录组变化和特定转录本的丰富性提供了新的见解。