Differential expression and prediction of function of lncRNAs in the ovaries of low and high fecundity Hanper sheep

Abstract

Contents 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.

LncRNA‐412.25 activates the LIF/STAT3 signaling pathway in ovarian granulosa cells of Hu sheep by sponging miR‐346

“…Moreover, some DELs were enriched in several signaling pathways involved in female reproduction, including steroid biosynthesis, 33 prolactin, 34 Jak–STAT, 35 and Wnt signaling pathways, 36 suggesting that the DELs have specific roles in the regulation of follicular development and fecundity in Hu sheep. This observation is supported by the results of previous studies in which lncRNAs were shown to be possibly associated with fecundity in sheep or goats 10–14,16,17,19,37 …”

“…This observation is supported by the results of previous studies in which lncRNAs were shown to be possibly associated with fecundity in sheep or goats. [10][11][12][13][14]16,17,19,37 In the current study, we characterized a novel transcript, lncRNA-412.25 (from >5 mm healthy follicles), which was expressed at significantly higher levels in the HPBB group than in the LPB+ or LPBB groups. A different expression pattern was observed in different-sized healthy follicles from Hu sheep.…”

“…9 However, few lncRNAs have been identified in domestic animals. Although the expression profiles of lncRNAs in the ovary, uterus, and pituitary glands of sheep (small tail Han sheep, Dorset sheep, Hanper sheep, and Hu sheep breeds) [10][11][12][13][14][15][16][17][18] and goats (Anhui white goats) 19 with different prolificacy indicate their importance in determining fecundity, the mechanisms underlying the effect of lncRNAs on fecundity in Hu sheep have not been elucidated.…”

Differential Expression and Functional Analysis of CircRNA in the Ovaries of Low and High Fecundity Hanper Sheep

“…Through miRNA and lncRNA analysis of FecB BB Small Tail Han sheep and FecB++ Dorset sheep, it was found the differentially expressed genes on cell apoptosis and proliferation were affected by gene mutation [2,3] and participated in progesterone mediated steroid biosynthesis and oocyte meiosis pathway [4]. Xist (loc101112291) and Gtl2 (loc101123329) were found to be highly expressed in Hanper sheep, suggesting the regulation of follicular development through methylation processes [5]. Mir-6404 and mir-29c are involved in the regulation of high and low fecundity in goats [6].…”

A single-cell atlas of the single versus multiple parous Hu Sheep ovary

“…Cells have different functions in the specific biological cycle of the ovary and contribute to the maturation of follicles [7]. Previous studies have taken the ovary as a whole [8,9]. Few studies have been conducted to investigate the effect of different cells in the ovary on reproductive performance.…”