Search

Litter size is a critical economic trait in livestock, but only a few studies have focused on associated indel mutations in BMPR1B, a key regulator of ovulation and litter size in sheep. We evaluated the effects of BMPR1B mutations on the reproductive performance of sheep. We used Hu, East Friesian, and East Friesian/Hu crossbred sheep as experimental subjects and identified a novel 90 bp deletion in BMPR1B, which coincides with the c.746A > G (FecB mutation) genotype. The correlation between the two loci and litter size was then evaluated. We identified three genotypes for the Del-90bp locus, namely, II, ID, and DD, and three genotypes for the c.746A > G locus, namely ++, B+, and BB. Both Del-90bp and c.746A > G significantly affected the litter size of Hu and East Friesian/Hu crossbred sheep. Linkage disequilibrium analysis revealed a strong linkage disequilibrium between these loci in Hu sheep and the F1 population (r2 > 0.33), which suggests that detecting this 90 bp deletion might be a simple method to identify the likely carriers of c.746A > G. However, the function of this 90-bp deletion still needs further exploration. We provide genetic data that can be used as a reference for the breeding of improved prolific traits in sheep. [ABSTRACT FROM AUTHOR]

microRNAs (miRNAs) and circular RNAs (circRNAs) are important for endometrial receptivity establishment and embryo implantation in mammals. miR‐34a and miR‐34c are highly expressed in caprine receptive endometrium (RE). Herein, the functions and mechanisms of miR‐34a/c in caprine endometrial epithelial cell (CEEC) apoptosis and RE establishment were investigated. miR‐34a/c downregulated the expression level of centrosomal protein 55 (CEP55) and were sponged by circRNA8073 (circ‐8073), thereby exhibiting a negative interaction in CEEC. miR‐34a/c induced CEEC apoptosis by targeting circ‐8073/CEP55 through the regulation of the RAS/RAF/MEK/ERK and phosphoitide 3‐kinase (PI3K)/protein kinase B (AKT)/mammalian target of rapamycin (mTOR) pathways. Positive and negative feedback loops and cross‐talk were documented between the RAS/RAF/MEK/ERK and PI3K/AKT/mTOR pathways. miR‐34a/c regulated the levels of RE marker genes, including forkhead box M1, vascular endothelial growth factor, and osteopontin (OPN). These results suggest that miR‐34a/c not only induce CEEC apoptosis by binding to circ‐8073 and CEP55 via the RAS/RAF/MEK/ERK and PI3K/AKT/mTOR pathways, but may also regulate RE establishment in dairy goats. [ABSTRACT FROM AUTHOR]

Transcriptomics is an established powerful tool to identify potential mRNAs and ncRNAs (non‐coding RNAs) for endometrial receptivity. In this study, the goat endometrium at estrus day 5 (ED5) and estrus day 15 (ED15) were selected to systematically analyse the differential expressed genes (DEGs) what were induced by the embryo. There were 1,847 genes which were significantly differential expressed in endometrium induced by the embryo at ED5, and 1,346 at ED15 (p‐value <.05). Secreted phosphoprotein 1 (SPP) was the responsive genes for embryo in the goat endometrium during estrus cycle, neurotensis (NTS) and pleiotrophin (PTN) were the responsive genes for embryo in the goat endometrium at ED5, Testin (TES) and Phosphate and Tension Homology Deleted on Chromsome ten (PTEN) at ED15. Furthermore, Gene Ontology (GO) and Kyoto Encyclopedia of Genes (KEGG) analysis revealed cytoplasm and Endocytosis were indispensable for the endometrium development in dairy goat. In a word, this resulting view of the transcriptome greatly uncovered the global trends in mRNAs expression induced by the embryo in the endometrium of dairy goats. [ABSTRACT FROM AUTHOR]

Despite the fact that long noncoding RNAs (lncRNAs) play roles in almost all biological processes, little is known about their biological function in the endometrium during the formation of endometrial receptivity. In this study, a comprehensive analysis of lncRNAs in goat endometrial tissues on Day 5 (prereceptive endometrium, PE) and Day 15 (receptive endometrium, RE) of pregnancy was performed by using RNA‐Seq. As a result, 668 differentially expressed lncRNAs (DELs) were found between the PE and RE. Further study showed that lncRNA882, regulated by estrogen (E2) and progestin (P4), could act as competing endogenous RNAs (ceRNAs) for miR‐15b, which inhibited the expression of transforming growth factor‐b‐activated kinase 1 binding protein 3 (TAB3) and then indirectly regulated the level of leukemia inhibitory factor (LIF). This was helpful for the formation of endometrial receptivity in dairy goats. In conclusion, we elucidated the endometrium lncRNA profiles of PE and RE in dairy goats; lncRNA882 acted as a ceRNA for miR‐15b and then indirectly regulated the level of LIF in goat endometrial epithelium cells. Thus, this study helped us to better understand the molecular regulation of endometrial receptivity in dairy goats. This study provides the first comprehensive analysis of long noncoding RNAs (lncRNAs) in goat endometrium at two developmental stages, which could have functional roles in the formation of endometrial receptivity. Importantly, we combine RNA‐Seq with detailed mechanistic studies to describe that lncRNA882 acts as a competing competing endogenous RNA (ceRNA) for miR‐15b, directly regulates the transforming growth factor‐b‐activated kinase 1 binding protein 3 (TAB3), and then indirectly regulates the level of leukemia inhibitory factor (LIF), which is helpful for the formation of endometrial receptivity in dairy goats. As the roles of candidate lncRNAs in goat endometrium have not yet been fully identified and understood, this study should provide valuable resource for further studies [ABSTRACT FROM AUTHOR]

Circular RNAs (circRNAs) in various tissues and cell types from mammalian sources have been studied. However, present knowledge on circRNAs in the development of pre‐receptive endometrium (PE) in dairy goats is limited. In the pre‐receptive endometrium of dairy goats, higher circRNA3175 (ciR3175) levels, lower miR‐182 levels and higher Testin (TES) levels were detected. And ciR3175 could decreased the miR‐182 levels by acting as a miRNA sponge, and miR‐182 could down‐regulated the expression level of TES via the predicted target site in endometrial epithelial cells (EECs) in vitro. Via this way, ciR3175 functioned as a competing endogenous RNAs (ceRNA) that sequestered miR‐182, thereby protecting TES transcripts from miR‐182‐mediated suppression in EECs in vitro. Further, TES inhibited EECs apoptosis by decreasing the expression level of BCL‐2/BAX via the MAPK pathway. Thus, a ciR3175‐miR182‐TES pathway in the endometrium was identified in EECs, and the modulation of which could emerge as a potential target in regulating the pre‐receptive endometrium development in dairy goats. [ABSTRACT FROM AUTHOR]

The mammary gland, crucial for milk production in mammals, presents challenges for in vitro study due to its complex structure and limited cell lifespan. We addressed this by introducing the SV40 large T antigen into primary mammary epithelial cells (MECs) from sheep, creating an immortalized T‐tag MEC line. This line, stable for over 50 passages, maintained typical epithelial cell morphology during long‐term culture. Through transcriptome sequencing and validation, we discovered 3833 differentially expressed genes between MECs and T‐tag MEC line, encompassing key biological processes and signaling pathways like cell cycle, p53, and cancer. The cell line, expressing MEC markers (KRT8, KRT18, proliferating cell nuclear antigen, SV40, CSN2, and acetyl‐CoA carboxylase alpha), proved capable of synthesizing milk fat and protein. Despite its infinite proliferation potential, the T‐tag MEC line showed no tumor formation in mice or cell migration in vitro, indicating stability. This development offers a valuable resource for studying MECs in dairy sheep, facilitating the advancement of long‐term culture systems and in vitro lactation bioreactors. [ABSTRACT FROM AUTHOR]

Development of the receptive endometrium (RE) from the pre-receptive endometrium (PE) is essential for embryo implantation, but its molecular mechanisms have not been fully understood. In this study, lncRNA-miRNA-mRNA and circRNA-miRNA-mRNA networks were constructed to explore the functions of potential competing endogenous RNAs (ceRNA) during the development of RE in dairy goats. We observed that circRNA8073 (ciR8073) decreased the levels of miR-181a by acting as a miRNA sponge. This effect indirectly increased the expression of neurotensin in endometrial epithelial cells (EECs). Neurotensin then inhibited EEC apoptosis by increasing the expression of BCL-2/BAX in favor of BCL-2 via the MAPK pathway and also induced increased expression of leukemia-inhibitory factor, cyclo-oxygenase 2, vascular endothelial growth factor A, and homeobox A10. We have thus identified a ciR8073-miR181a-neurotensin pathway in the endometrium of dairy goats. Through this pathway, ciR8073 functions as a ceRNA that sequesters miR-181a, thereby protecting neurotensin transcripts from miR-181a-mediated suppression in EECs., (Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.)