Skeletal muscle satellite cells (MuSCs) can proliferate, differentiate, and self-renew, and can also participate in muscle formation and muscle injury repair. Long noncoding RNAs (lncRNAs) can play an important role with the RNA binding protein and microRNAs (miRNAs) to regulate the myogenesis of bovine MuSCs, however, its molecular mechanism is still being explored. In this study, differentially expressed 301 lncRNAs were identified during the myogenic differentiation of cells based on an in vitro model of induced differentiation of bovine MuSCs using RNA sequencing (RNA-seq). Based on the ability of miR-206 to regulate myogenic cell differentiation, a new kind of lncRNA-lncA2B1 without protein-coding ability was found, which is expressed in the nucleus and cytoplasm. Subsequently, lncA2B1 inhibited cell proliferation by downregulating the expression of the proliferation marker Pax7 and promoted myogenic differentiation by upregulating the expression of the differentiation marker MyHC, whose regulatory function is closely related to miR-206. By RNA pulldown/LC-MS experiments, heterogeneous ribonucleoprotein A2/B1 (HNRNPA2B1), and DExH-Box Helicase 9 (DHX9) were identified as common binding proteins of lncA2B1 and miR-206. Overexpression of lncA2B1 and miR-206 significantly upregulated the expression level of HNRNPA2B1. Downregulation of HNRNPA2B1 expression significantly decreased the expression level of the differentiation marker MyHC, which indicates that miR-206 and lncA2B1 regulate myogenic differentiation of bovine MuSCs by acting on HNRNPA2B1. This study screened and identified a novel lncRNA-lncA2B1, which functions with miR-206 to regulate myogenesis via the common binding proteins HNRNPA2B1. The results of this study provide a new way to explore the molecular mechanisms by which lncRNAs and miRNAs regulate muscle growth and development.

MicroRNAs (miRNAs) are essential regulators of numerous biological processes in animals, including adipogenesis. Despite the abundance of miRNAs associated with adipogenesis, their exact mechanisms of action remain largely unknown. Our study highlights the role of bta-miR-484 as a major regulator of adipocyte proliferation, apoptosis, and differentiation. Here, we demonstrated that the expression of bta-miR-484 initially increased during adipogenesis before decreasing. Overexpression of bta-miR-484 in adipocytes ultimately inhibited cell proliferation and differentiation, reduced the number of EdU fluorescence-stained cells, increased the number of G1 phase cells, reduced the number of G2 and S phase cells, and downregulated the expression of proliferation markers (CDK2 and PCNA) and differentiation markers (CEBPA, FABP4, and LPL). Additionally, overexpression of bta-miR-484 promoted the expression of apoptosis-related genes (Caspase 3, Caspase 9, and BAX), and increased the number of apoptotic cells observed via flow cytometry. In contrast, bta-miR-484 inhibition in adipocytes yielded opposite effects to those observed during bta-miR-484 overexpression. Moreover, luciferase reporter assays confirmed SFRP1 as a target gene of bta-miR-484, and revealed that bta-miR-484 downregulates SFRP1 mRNA expression. These findings offer compelling evidence that bta-miR-484 targets SFRP1, inhibits proliferation and differentiation, and promotes apoptosis. Therefore, these results offer novel insights into the bta-miR-484 regulation of adipocyte growth and development.

The success of assisted reproductive technology is contingent upon the growth potential of embryos post-vitrification process. When compared to in vivo embryos, it has been found that the high intracellular lipid accumulation inside the in vitro-derived embryos results in poor survival during vitrification. Based on this finding, the present study assessed the impact of incorporating forskolin and linoleic acid (FL) entering in vitro culture (IVC) on the embryos’ cryo-survival, lipid content, and viability throughout vitrification. Lipid metabolomics and single-cell RNA sequencing (scRNA-seq) techniques were used to determine the underlying mechanism that the therapies were mimicking. It was observed that out of 726 identified lipids, 26 were expressed differentially between the control and FL groups, with 12 lipids upregulated and 14 lipids downregulated. These lipids were classified as Triacylglycerol (TG), Diacylglycerol (DG), Phosphatidylcholine (PC), and so on. A total of 1079 DEGs were detected between the FL and control groups, consisting of 644 upregulated genes and 435 downregulated genes. These DEGs were significantly enhanced in the arachidonic acid metabolism, lipolysis, fatty acid metabolism, cAMP signaling pathway, and other critical developmental pathways. Based on the observation, it was concluded that forskolin and linoleic acid decreased the droplet content of embryos by modulating lipid metabolism, thus enhancing the vitrified bovine embryos’ cryo-survival.

A healthy uterine environment is essential for establishing and maintaining pregnancy and normal embryo development after insemination. In this context, the primary objectives of this study were to assess the genetic background of vaginal discharge score (VDS) traits during the voluntary waiting period in Holstein cows and to identify genomic regions and candidate genes influencing postpartum uterine health based on the integration of phenotypic, genomic, and transcriptomic data sets. Genetic parameters of 5 VDS traits defined according to lactation stage (VDS1, VDS2, VDS3, VDS4, and VDS5) were estimated based on VDS records from 64,241 Holstein cows that calved between 2019 and 2023 and genomic information from 2,489 cows. Genome-wide association studies (GWAS) were performed aiming to identify genomic regions associated with VDS traits. Differentially expressed genes and modular genes were obtained through RNA-seq data of uterine secretion from 6 healthy and 6 diseased cows. The VDS traits had low heritability estimates ranging from 0.006 ± 0.002 to 0.081 ± 0.011. Among the VDS traits, there were relatively strong genetic correlations between VDS1 (0-14 DIM) and metritis (0.678-0.763) as well as VDS3 (29-55 DIM) and endometritis (0.579-0.628). A total of 190 genes harboring 32 significant SNPs were identified as candidate genes regulating VDS in primiparous cows. The candidate genes identified were significantly enriched for pathways involved in cytokine-cytokine receptor interaction, MAPK signaling, and oxytocin signaling. Based on RNA-seq data of uterine secretions, 2,803 differentially expressed genes and 3,570 modular genes were identified. Furthermore, 7 genes were identified based on GWAS, differential gene expression, and weighted gene co-expression network analysis. The genes VSTM1, IL10RA, FXYD5, C2CD5, CETN4, ALS2CL, and PBX1 were considered to be the most promising candidate genes influencing postpartum uterine health in Holstein cows. This study provides novel insights on the genetic background of postpartum uterine health in Holstein cows. The results obtained can contribute to further refinements of selection indexes for improving uterine health and fertility in dairy cattle.