College of Animal Science and Technology, Hebei Agricultural University, Baoding, China.
Discipline of Obstetrics and Gynaecology, School of Medicine, Robinson Research Institute, University of Adelaide, Adelaide, SA, Australia.
Reprod Domest Anim. 2021 Apr;56(4):604-620. doi: 10.1111/rda.13898. Epub 2021 Jan 27.
Litter size is an important trait that determines the production efficiency of sheep bred for meat. Its detailed investigation can reveal the molecular mechanisms that control the fecundity of sheep and possibly accelerate the breeding process of new varieties of sheep that have high prolificacy. Long non-coding RNAs (lncRNAs) have proven to be an important factor in the regulation of follicular development. However, the mechanisms by which lncRNAs regulate litter size in sheep remain unclear. In the present study, ovarian tissues from the follicular (F) or luteal phase (L) of Hanper sheep that were either monotocous (M) or polytocous (P; FM, FP, LM and LP groups) were collected and sequenced to identify differentially expressed lncRNAs and predict their function. The results indicate that the number of up- and down-regulated lncRNAs in the follicular phase (FM vs. FP) was 95 and 111 and 109 and 49, respectively, in the luteal phase (LM vs. LP). The functional enrichment of the different lncRNAs coexpressed with mRNA was analysed. The results demonstrated that the KISS1-GnRH-LH/FSH-E2 and EGF-EGFR-RAS-PI3K signalling pathways promoted the initiation of the primordial period, follicular development and ovulation in the follicular phase (FM vs. FP). During the luteal phase (LM vs. LP), the production and development of the corpus luteum in ewes was influenced by the KITLG-KIT/FGF-FGFR/HGF-MET-RAS-ERK signalling pathway. STEM clustering functional enrichment analysis of the differentially expressed lncRNAs indicated that profile11 was principally enriched in the Cytokine-Jak-STAT, PDGF-PDGFR-PI3K and KITLG-KIT-RAS-ERK signalling pathways. By analysis of the differential expression of the lncRNAs and their expression in each group, lncRNAs Xist (loc101112291) and Gtl2 (loc101123329) were found to be highly expressed, suggesting that regulation of follicular development was mediated through methylation processes.
产仔数是决定用于肉用绵羊生产效率的重要性状。详细研究可以揭示控制绵羊繁殖力的分子机制，并可能加速具有高繁殖力的新绵羊品种的培育过程。长链非编码 RNA（lncRNA）已被证明是调节卵泡发育的重要因素。然而，lncRNA 调节绵羊产仔数的机制尚不清楚。本研究采集了处于卵泡期（F）或黄体期（L）的单胎（M）或多胎（P；FM、FP、LM 和 LP 组）汉普绵羊的卵巢组织进行测序，以鉴定差异表达的 lncRNA 并预测其功能。结果表明，在卵泡期（FM 与 FP）中，上调和下调的 lncRNA 数分别为 95 和 111，以及 109 和 49；在黄体期（LM 与 LP）中，上调和下调的 lncRNA 数分别为 111 和 49，以及 109 和 49。分析了与 mRNA 共表达的不同 lncRNA 的功能富集。结果表明，KISS1-GnRH-LH/FSH-E2 和 EGF-EGFR-RAS-PI3K 信号通路促进了原始卵泡期、卵泡发育和排卵的启动（FM 与 FP）。在黄体期（LM 与 LP）中，KITLG-KIT/FGF-FGFR/HGF-MET-RAS-ERK 信号通路影响了母羊黄体的产生和发育。差异表达 lncRNA 的 STEM 聚类功能富集分析表明，profile11 主要富集于细胞因子-Jak-STAT、PDGF-PDGFR-PI3K 和 KITLG-KIT-RAS-ERK 信号通路。通过分析 lncRNA 的差异表达及其在各组中的表达，发现 lncRNA Xist（loc101112291）和 Gtl2（loc101123329）表达水平较高，提示卵泡发育的调节是通过甲基化过程介导的。
