Integrated Analysis of miRNA-mRNA Network Reveals Different Regulatory Patterns in the Endometrium of Meishan and Duroc Sows during Mid-Late Gestation

Abstract

Embryo loss is a major factor affecting profitability in the pig industry. Embryonic mortality occurs during peri-implantation and mid-late gestation in pigs. Previous investigations have shown that the embryo loss rate in Meishan pigs is significantly lower than in commercial breeds. Most studies have focused on embryonic mortality during early gestation, but little is known about losses during mid-late gestation. In this study, we performed a transcriptome analysis of endometrial tissue in mid-late gestation sows (gestation days 49 and 72) sampled from two breeds (Meishan (MS) and Duroc (DU)) that have different embryo loss rates. We identified 411, 1113, 697, and 327 differentially expressed genes, and 14, 36, 57, and 43 differentially expressed miRNAs in four comparisons (DU49 vs. DU72, DU49 vs. MS49, DU72 vs. MS72, and MS49 vs. MS72), respectively. Subsequently; seven differentially expressed mRNAs and miRNAs were validated using qPCR. Functional analysis suggested the differentially expressed genes and miRNAs target genes mainly involved in regulation of hormone levels, blood vessel development, developmental process involved in reproduction, embryonic placenta development, and the immune system. A network analysis of potential miRNA-gene interactions revealed that differentially expressed miRNAs in Meishan pigs are involved in the response to estradiol and oxygen levels, and affect angiogenesis and blood vessel development. The binding site on ssc-miR-503 for epidermal growth factor (EGF) and the binding site on ssc-miR-671-5p for estrogen receptor α (ESR1) were identified using a dual luciferase assay. The results of this study will enable further exploration of miRNA-mRNA interactions important in pig pregnancy and will help to uncover molecular mechanisms affecting embryonic mortality in pigs during mid-late gestation.

Identification of Differentially Expressed MicroRNAs and Their Potential Target Genes in Adipose Tissue from Pigs with Highly Divergent Backfat Thickness

“…We detected 403 known mature miRNAs among the six libraries using RNA-seq, which is a higher number than the previously reported numbers of miRNAs detected in porcine adipose tissue by RNA-seq (namely, 172 [27], 222 [28], 227 [15], 239 [14], 283 [12], and 309 [16]), but lower than the number (409) obtained by Davoli et al [17]. Although miRBase does have some weaknesses, it has been used widely for identifying porcine miRNA and is a popular and reliable platform for miRNA researches [16,17,29,30]. Although MiRgeneDB (https://mirgenedb.org/) [31] and miRCarta (https://mircarta.cs.uni-saarland.de/) [32] provide more accurate and reliable miRNA annotations, miRNAs from porcine species are not included in the current MiRgeneDB.…”

Differential MicroRNA Expression in Porcine Endometrium Related to Spontaneous Embryo Loss during Early Pregnancy

“…Studies have shown that miR-365-5p can target RNA-binding protein with serine-rich domain 1 ( RNPS1) , Keratin 14 ( KRT14) , and DnaJ heat shock protein family (Hsp40) member B6 ( DNAJB6) in porcine Alveolar Macrophages, thereby affecting interferon-mediated immune response [ 42 ]. Previous studies have shown that the differentially expressed miR-671-5p in the endometrium of Meishan and Duroc sows affects maternal placental development by targeting the Estrogen Receptor 1 ( ESR1) gene [ 5 , 43 ]. Among the genes targeted by the above miRNAs.…”

“…The failure of adjustment and coordination all contribute to spontaneous embryo loss. Insufficient blood supply to the uterus has been demonstrated to cause spontaneous embryo loss [ 3 , 4 , 5 , 6 , 7 ]. Previous studies found that vascular endothelium growth factors, hypoxia-inducible factor 1-α, IFN-γ, etc., all affect the angiogenesis between mother and fetus, ultimately leading to healthy and arresting embryos [ 8 , 9 ].…”

Screening of Potential Key Genes Related to Tubal Factor Infertility Based on Competitive Endogenous RNA Network

“…However, the molecular biological mechanism of TFI is still unclear (Malogajski et al, 2019). Meanwhile, embryo implantation requires a precise synchronism between the receptive uterus (during the implantation window) and activated blastocyst (Abbas et al, 2020;Yang et al, 2020). Therefore, an in-depth study of the key genes and mechanisms of endometrium during the implantation window period in patients with TFI is of great significance for the pregnancy of TFI.…”