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NORSF is a nuclear long noncoding RNA (lncRNA) that contributes to the follicular atresia and restrains 17β‐estradiol (E2) release by granulosa cells (GCs). Importantly, it is also a potential candidate gene in the quantitative trait locus (QTLs) for sow fertility traits. We identified NORSF as a candidate (causal) gene affecting sow fertility traits. A novel G–A variant was discovered at −478 nt of the NORSF promoter and termed as g.−478G>A. Association analysis revealed that this variant was associated with sow fertility traits (e.g., the total number of piglets born, the total number of piglets born alive, and the number of healthy piglets). Mechanistically, the g.−478G>A variant reduced the binding activity of the NORSF promoter to its transcription activator regulatory factor X7 (RFX7), leading to decreased NORSF promoter activity and transcription levels in sow GCs (sGCs), and weakened inhibitory effects on the transcription of CYP19A1, which encodes a rate‐limiting enzyme for E2 synthesis and E2 release by sGCs. In addition, RFX7 is transcriptionally activated by P53, which restrains E2 release from sGCs via the RFX7/NORSF/CYP19A1 pathway. These findings indicate that the lncRNA NORSF is a causal gene in QTLs for sow fertility traits and define the P53/NORSF/CYP19A1 pathway as a new signaling pathway affecting sow reproduction, which provides a new target for improving female fertility. [ABSTRACT FROM AUTHOR]

Sow fertility is an economically important quantitative trait. Hundreds of quantitative trait loci (QTLs) containing tens of thousands of potential candidate genes are excavated. However, among these genes, non‐coding RNAs including long non‐coding RNAs (lncRNAs) are often overlooked. Here, it is reported that NORSF is a novel causal lncRNA for sow fertility traits in QTLs. QTLs are characterized for sow fertility traits at the genome‐wide level and identified 4,630 potential candidate lncRNAs, with 13 differentially expressed during sow follicular atresia. NORSF, a lncRNA that involved in sow granulosa cell (sGC) function, is identified as a candidate gene for sow fertility traits as a G to A transversion at 128 nt in its transcript is shown to be markedly associated with sow fertility traits. Mechanistically, after forming the RNA:dsDNA triplexes with the promoter of Caspase8, NORSF transcript with allele G binds to an RNA‐binding protein (RBP) NR2C1 and recruits it to the promoter of Caspase8, to induce Caspase8 transcription in sGCs. Functionally, this leads to a loss of inducing effect of NORSF on sGC apoptosis by inactivating the death receptor‐mediated apoptotic pathway. This study identified a novel causal lncRNA that can be used for the genetic improvement of sow fertility traits. [ABSTRACT FROM AUTHOR]

Increasing evidence shows that lncRNAs, an important kind of endogenous regulator, are involved in the regulation of follicular development and female fertility, but the mechanism remain largely unknown. In this study, we found that SDNOR, a recently identified antiapoptotic lncRNA, is a potential multifunctional regulator in porcine follicular granulosa cells (GCs) through RNA-seq and multi-dimension analyses. SDNOR-mediated regulatory networks were established and identified that SOX9, a transcription factor inhibited by SDNOR, mediates SDNOR's regulation of the transcription of downstream targets. Functional analyses showed that loss of SDNOR significantly impairs GC morphology, inhibits cell proliferation and viability, reduces E2/P4 index, and suppresses the expression of crucial markers, including PCNA, Ki67, CDK2, CYP11A1, CYP19A1, and StAR. Additionally, after the detection of ROS, SOD, GSH-Px, and MDA, we found that SDNOR elevates the resistance of GCs to oxidative stress (OS) and also inhibits OS-induced apoptosis. Notably, GCs with high SDNOR levels are insensitive to oxidative stress, leading to lower apoptosis rates and higher environmental adaptability. In summary, our findings reveal the regulation of porcine GCs in response to oxidative stress from the perspective of lncRNA and demonstrate that SDNOR is an essential antioxidative lncRNA for maintaining the normal state and function of GCs. [ABSTRACT FROM AUTHOR]

microRNAs (miRNAs) are well known to be important in mammalian female fertility. However, the genetic regulation of miRNAs associated with female fertility remains largely unknown. Here, we report that two single‐nucleotide variants (SNVs) in the miR‐23a promoter strongly influence miR‐23a transcription and function in granulosa cell (GC) apoptosis. Two novel SNVs, g.‐283G>C and g.‐271C>T, were detected in the porcine miR‐23a promoter by pooled‐DNA sequencing. Furthermore, SNVs in the promoter region influenced miR‐23a transcription in porcine GCs by altering its promoter activity. Functionally, SNVs in the promoter strongly influenced miR‐23a regulation of early apoptosis in porcine GCs cultured in vitro. In addition, a preliminary association analysis showed that the combined genotypes of the two SNVs, rather than a single SNV, were tentatively associated with sow fertility traits in a Large White population. Overall, our findings suggest that the SNVs g.‐283G>C and g.‐271C>T in the miR‐23a promoter are causal variants affecting GC apoptosis and miR‐23a may be a potential small‐molecule nonhormonal drug for regulating female fertility. [ABSTRACT FROM AUTHOR]

Objectives: Transforming growth factor β1 (TGF‐β1), an essential cytokine belongs to TGF‐β superfamily, is crucial for female fertility. Increasing evidence show that long noncoding RNAs (lncRNAs) influence the state of granulosa cells (GCs). This study aimed to detect the effects of TGF‐β1 on the lncRNA transcriptome, and investigate whether lncRNAs mediate the functions of TGF‐β1 in GCs. Material and Methods: RNA‐seq and bioinformatics analyses were performed to identify and characterize the differentially expressed lncRNAs (DElncRNAs). The regulatory mechanism of TGF‐β1 to lncRNA transcriptome was analyzed by chromatin immunoprecipitation. The effects of lncRNAs on the antiapoptotic and proproliferative functions of TGF‐β1 were examined by morphological analysis, fluorescence‐activated cell sorting, Cell Counting Kit‐8, and Western blot. Results: A total of 72 DElncRNAs highly sensitive to TGF‐β1 were identified with the criteria of |log2(fold chage)| ≥ 3 and false discovery rate < 0.05. Functional assessment showed that DElncRNAs were enriched in TGF‐β, nuclear factor kappa B, p53, and Hippo pathways which are crucial for the normal state and function of GCs. Importantly, SMAD4 is essential for the regulation of TGF‐β1 to lncRNA transcriptome. In vitro studies confirmed that TGF‐β1 induced TEX14‐IT1 transcription in a SMAD4‐dependent manner, and TEX14‐IT1 mediated the antiapoptotic and proproliferative effects of TGF‐β1 in GCs. Conclusions: Our findings demonstrate that TGF‐β1 alters lncRNA transcriptome in a SMAD4‐dependent manner, and highlight that lncRNAs mediate the functions of TGF‐β1 in GCs, which contribute to a better understanding of the epigenetic regulation of female fertility. [ABSTRACT FROM AUTHOR]