Yin, Yikai, Zhang, Jian, Li, Xindi, Duan, Mengqi, Zhao, Mingxuan, Zhang, Feifan, Chamba, Yangzom, and Shang, Peng
Simple Summary: The problem of low fertility in Tibetan pigs has a long history. In order to solve the problem of low fertility in Tibetan pigs, in this study, we successfully constructed cDNA libraries of the transcriptome from ovarian tissues of Tibetan and Yorkshire pigs using RNA-Seq technology, analyzed and screened the genes significantly enriched in the pathways closely related to the regulation of reproduction, and finally identified AR, CYP11A1, CYP17A1, INHBA, ARRB2, EGFR, ETS1, HSD17B1, IGF1R, MIF, SCARB1, and SMAD4 as important candidate genes. The 12 differentially expressed genes screened in relation to reproduction were validated using RT-qPCR. The results showed that six genes were highly significantly (p < 0.01) higher in expression in Tibetan pigs than in Yorkshire pigs, i.e., AR, CYP17A1, EGFR, ETS1, IGF1R, and SMAD4; on the other hand, six genes were highly significantly (p < 0.01) lower in expression in Tibetan pigs than in Yorkshire pigs, i.e., CYP11A1, INHBA, ARRB2, HSD17B, MIF, SCARB1. This study provides a theoretical basis for improving the regulatory genes in Tibetan pigs. The purpose of this study was to explore and verify genes that regulate the reproductive traits of Tibetan pigs at the mRNA level. The ovarian tissues of Tibetan pigs (TPs) and Yorkshire pigs (YPs) were selected as research objects, and cDNA libraries of the ovarian tissue transcripts of Tibetan pigs and Yorkshire pigs were successfully constructed by the RNA-Seq technique. A total of 651 differentially expressed genes (DEGs) were screened, including 414 up-regulated genes and 237 down-regulated genes. Through GO and KEGG enrichment analysis, it was found that these differentially expressed genes were significantly enriched in cell process, reproductive process, reproduction, cell proliferation, binding, and catalytic activity, as well as oxidative phosphorylation, endocrine resistance, thyroid hormone, Notch, and other signal transduction pathways. Genes significantly enriched in pathways closely related to reproductive regulation were analyzed and selected, and the AR, CYP11A1, CYP17A1, INHBA, ARRB2, EGFR, ETS1, HSD17B1, IGF1R, MIF, SCARB1, and SMAD4 genes were identified as important candidate genes. Twelve differentially expressed genes related to reproduction were verified by RT-qPCR. The results showed that the expression of the AR, CYP17A1, EGFR, ETS1, IGF1R, and SMAD4 genes was significantly higher in Tibetan pigs than in Yorkshire pigs, while the expression of the CYP11A1, INHBA, ARRB2, HSD17B, MIF, and SCARB1 genes in Tibetan pigs was significantly lower than in Yorkshire pigs. The purpose of this study is to provide a theoretical basis for exploring the molecular mechanism of reproductive trait effect genes and the application of molecular breeding in Tibetan pigs. [ABSTRACT FROM AUTHOR]