Abstract
Background:
Reproduction traits are crucial for livestock breeding and represent key economic indicators in the domestic goat (Capra hircus) industry. The oviduct, a critical organ in female mammals, plays a pivotal role in several reproductive processes; however, its molecular mechanisms remain largely unknown. Non-coding RNA and mRNAs are essential regulatory elements in reproductive processes; yet their specific roles and regulatory networks in goat oviducts remain unclear.
Results:
In this study, we conducted small RNA sequencing of the oviduct in high- and low-fecundity goats during the follicular (FH and FL groups, n = 10) and luteal (LH and LL groups, n = 10) phase, profiling 20 tissue samples. Combinatorial whole-transcriptome expression profiles were applied to the same samples to uncover the competitive endogenous RNA (ceRNA) regulation network associated with goat fecundity. RT-qPCR was employed to validate the miRNA profiling results, and ceRNA regulatory networks were analyzed through luciferase assay. Gene set enrichment analysis (GSEA) confirmed that the cytokine-cytokine receptor interaction and TGF-β signaling pathway, both related to embryonic development, were enriched in DEM target genes. Additionally, miR-328-3p, a core miRNA, targets SMAD3 and BOP1, which are involved in the negative regulation of cell growth and embryonic development. TOB1 and TOB2, targeted by miR-204-3p, regulate cell proliferation via the protein kinase C-activating G-protein coupled receptor signaling pathway. Analyses of ceRNA regulatory networks revealed that LNC_005981 - miR-328-3p - SMAD3 and circ_0021923 - miR-204-3p - DOT1L may affect goats' reproduction, findings that were validated using luciferase assay.
Conclusion:
Analysis of whole-transcriptome profiling of goat oviducts identified several key miRNAs and ceRNAs that may regulate oocyte maturation, embryo development, and the interactions between the oviduct and gametes/early embryos, providing insights into the molecular mechanisms of reproductive regulatory networks.
Keywords:
Goat; Oviduct; Reproduction trait; ceRNA regulatory network; microRNA.