Construction of TF-lncRNA-miRNA-mRNA Regulatory Network Affecting Sow Reproduction Based on QTLs for Corpus Luteum Number.

The corpus luteum number in sows is a key reproductive indicator for measuring ovulation rate and reproductive efficiency. Its formation is precisely regulated by a complex gene regulatory network composed of multi-level molecular interactions. To systematically elucidate the molecular basis of this trait, this study comprehensively analyzed genes located within QTL for corpus luteum number. This approach identified a series of key regulatory molecules specifically expressed in the ovary, including transcription factors (TFs), long non-coding RNAs (lncRNAs), and microRNAs (miRNAs). Using bioinformatics methods to predict the target genes of candidate miRNAs, combined with functional enrichment analysis, revealed that these target genes were significantly enriched in multiple core reproductive pathways closely related to cell proliferation, differentiation, and hormone regulation, including the ErbB signaling pathway, PI3K-Akt signaling pathway, and TGF-beta signaling pathway. Based on the above findings, this study ultimately constructed a TF-lncRNA-miRNA-mRNA network, which is associated with QTL for corpus luteum number. Furthermore, key genes were validated via quantitative real-time PCR (qRT-PCR). Significant positive correlations were identified between the transcription factor NEUROG2 and lncRNA LOC102167554, along with its potential target gene ESRP1, as well as between transcription factor SNAI2 and lncRNAs (LOC102167554, LOC102167796) and their potential target genes (FXR, ERBB4). In addition, the functional validation results showed that the interference of LOC102167554 significantly reduced the proliferation ability of sGCs. These key genes represent potential targets for genetic improvement of sow reproduction.