Clinic of Reproductive Medicine, Department for Farm Animals, Vetsuisse Faculty Zurich, University of Zurich, Lindau (ZH), Switzerland.
Present address: Department for Farm Animals and Veterinary Public Health, Clinical Unit for Herd Health Management in Ruminants, University of Veterinary Medicine, Vienna, Austria.
BMC Genomics. 2021 May 22;22(1):377. doi: 10.1186/s12864-021-07701-3.
Subfertility is a major problem in modern horse breeding. Especially, mares without clinical signs of reproductive diseases, without known uterine pathogens and no evidence of inflammation but not becoming pregnant after several breeding attempts are challenging for veterinarians. To obtain new insights into the cause of these fertility problems and aiming at improving diagnosis of subfertile mares, a comparative analysis of the intrauterine transcriptome in subfertile and fertile mares was performed. Uterine cytobrush samples were collected during estrus from 57 mares without clinical signs of uterine diseases. RNA was extracted from the cytobrush samples and samples from 11 selected subfertile and 11 fertile mares were used for Illumina RNA-sequencing.
The cytobrush sampling was a suitable technique to isolate enough RNA of high quality for transcriptome analysis. Comparing subfertile and fertile mares, 114 differentially expressed genes (FDR = 10%) were identified. Metascape enrichment analysis revealed that genes with lower mRNA levels in subfertile mares were related to 'extracellular matrix (ECM)', 'ECM-receptor interaction', 'focal adhesion', 'immune response' and 'cytosolic calcium ion concentration', while DEGs with higher levels in subfertile mares were enriched for 'monocarboxyl acid transmembrane transport activity' and 'protein targeting'.
Our study revealed significant differences in the uterine transcriptome between fertile and subfertile mares and provides leads for potential uterine molecular biomarkers of subfertility in the mare.
不孕是现代马种繁育中的一个主要问题。特别是那些没有生殖系统疾病临床症状、没有已知子宫病原体、没有炎症迹象，但在多次配种尝试后仍未能怀孕的母马，对兽医来说是一个挑战。为了深入了解这些生育问题的原因，并旨在改善不孕母马的诊断，对不孕和正常受配母马的子宫转录组进行了比较分析。在发情期，从 57 匹没有子宫疾病临床症状的母马中采集子宫细胞刷样本。从细胞刷样本中提取 RNA，选择 11 匹不孕和 11 匹正常受配母马的样本进行 Illumina RNA 测序。
细胞刷采样是一种从样本中分离足够高质量 RNA 进行转录组分析的有效方法。将不孕和正常受配母马进行比较，鉴定出 114 个差异表达基因（ FDR = 10%）。Metascape 富集分析表明，不孕母马中 mRNA 水平较低的基因与“细胞外基质（ECM）”、“ECM-受体相互作用”、“黏附斑”、“免疫反应”和“细胞质钙离子浓度”有关，而不孕母马中 mRNA 水平较高的 DEGs 则富集于“单羧酸跨膜转运活性”和“蛋白质靶向”。
本研究揭示了正常受配和不孕母马之间的子宫转录组存在显著差异，并为母马不孕的潜在子宫分子生物标志物提供了线索。
