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The long non-coding RNAs (lncRNAs) are emerging as essential regulators of the growth and development of skeletal muscles. However, little is known about the expression profiles of lncRNAs during the proliferation and differentiation of skeletal muscle satellite cells (MuSCs) in goats. In this study, we investigate potential regulatory lncRNAs that govern muscle development by performing lncRNA expression profiling analysis during the proliferation (cultured in the growth medium, GM) and differentiation (cultured in the differentiation medium, DM1/DM5) of MuSCs. In total, 1001 lncRNAs were identified in MuSC samples, and 314 differentially expressed (DE) (FDR < 0.05, |log2FC| > 1) lncRNAs were screened by pairwise comparisons from three comparison groups (GM-vs-DM1, GM-vs-DM5, DM1-vs-DM5). Moreover, we identified the cis-, trans-, and antisense-regulatory target genes of DE lncRNAs. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses showed that these target genes were significantly enriched in muscle development-related GO terms and KEGG pathways. In addition, the network of interactions between DE lncRNAs and their target genes was identified, which included well-known myogenesis regulators such as Myogenic differentiation 1 (MyoD), Myogenin (MyoG), and Myosin heavy chain (MyHC). Meanwhile, competing endogenous RNA (ceRNA) network analysis showed that 237 DE lncRNAs could bind to 329 microRNAs (miRNAs), while miRNAs could target 564 mRNAs. Together, our results provide a genome-wide resource of lncRNAs that may contribute to myogenic differentiation in goats and lay the groundwork for future investigation into their functions during skeletal muscle development. [ABSTRACT FROM AUTHOR]

Brown adipose tissue (BAT) plays a critical role in maintaining the body temperature in newborn lamb due to its unique non-shivering thermogenesis. Previous studies have found that BAT thermogenesis is regulated by several long non-coding RNAs (lncRNAs). Here, we identified a novel lncRNA, MSTRG.310246.1, which was enriched in BAT. MSTRG.310246.1 was localized in both the nuclear and cytoplasmic compartments. In addition, MSTRG.310246.1 expression was upregulated during brown adipocyte differentiation. Overexpression of MSTRG.310246.1 increased the differentiation and thermogenesis of goat brown adipocytes. On the contrary, the knockdown of MSTRG.310246.1 inhibited the differentiation and thermogenesis of goat brown adipocytes. However, MSTRG.310246.1 had no effect on goat white adipocyte differentiation and thermogenesis. Our results show that MSTRG.310246.1 is a BAT-enriched LncRNA that improves the differentiation and thermogenesis of goat brown adipocytes. [ABSTRACT FROM AUTHOR]

Long noncoding RNAs (lncRNAs) are involved in a variety of biological processes and illnesses. While a considerable number of lncRNAs have been discovered in skeletal muscle to far, their role and underlying processes during myogenesis remain mostly unclear. In this study, we described a new functional lncRNA named lncR-133a. Gene overexpression and interference studies in goat skeletal muscle satellite cells (MuSCs) were used to establish its function. The molecular mechanism by which lncR-133a governs muscle differentiation was elucidated primarily using quantitative real-time PCR (qRT-PCR), Western blotting, dual-luciferase activity assays, RNA immunoprecipitation, biotin-labeled probe, and RNA fluorescence in situ hybridization analyses. LncR-133a was found to be substantially expressed in longissimus thoracis et lumborum muscle, and its expression levels changed during MuSC differentiation in goats. We validated that lncR-133a suppresses MuSC differentiation in vitro. Dual-luciferase reporter screening, Argonaute 2 (AGO2) RNA immunoprecipitation assays, biotin-labeled lncR-133a capture, and fluorescence in situ hybridization showed that lncR-133a interacted with miR-133a-3p. Additionally, miR-133a-3p facilitated MuSC differentiation, but lncR-133a reversed this effect. The luciferase reporter assay and functional analyses established that miR-133a-3p directly targets fibroblast growth factor receptor 1 (FGFR1). Moreover, lncR-133a directly reduced miR-133a-3p's capacity to suppress FGFR1 expression, and positively regulated the phosphorylation of extracellular signal-regulated kinase 1/2 (ERK1/2). In summary, our results suggested that lncR-133a suppresses goat muscle differentiation by targeting miR-133a-3p and activating FGFR1/ERK1/2 signaling pathway. [ABSTRACT FROM AUTHOR]

Background: MicroRNAs (miRNAs) are a family of short non-coding RNA molecules and play important roles in various biological processes. However, knowledge of the expression profiles and function of miRNAs on the regulation of brown adipose tissue (BAT) thermogenesis remains largely unknown. Results: In this study, we found that brown adipose tissue (BAT) existed within the perirenal fat at 1 day after birth (D1) and transferred into white adipose tissue (WAT) at 30 days after birth (D30) by UCP1 protein expression and immunohistochemistry analysis. After that, we performed RNA sequencing on six libraries of goat BAT and WAT. A total of 238 known miRNAs and 1834 goat novel miRNAs were identified. Moreover, 395 differentially expressed miRNAs including 167 up-regulated and 228 down-regulated miRNAs were obtained in BAT. For the known BAT enriched miRNA, 30 miRNAs were enriched in goat BAT but not in mouse BAT. In addition, miR-433 was enriched in goat BAT but not in mouse BAT. Gain- and loss-of-function experiments reveal that miR-433 reduced the lipid accumulation of brown adipocytes and decreased the expression of BAT marker and mitochondrial related genes. However, miR-433 had no effect on lipid accumulation and thermogenesis in white adipocytes. In addition, miR-433 inhibited the expression of MAPK8 by targeting to the 3'UTR of MAPK8 gene. These data demonstrate that miR-433 acts as a negative regulator in controlling brown adipocytes differentiation and thermogenesis. Conclusion: The present study provides a detailed miRNAs expression landscape in BAT and WAT. Furthermore, we found that miR-433, which was highly expressed on BAT had a negative regulatory function on the thermogenesis and adipogenesis in goat brown adipocytes. This study provides evidence for understanding the role of miRNAs in regulating BAT thermogenesis and energy expenditure in goats. [ABSTRACT FROM AUTHOR]

Long noncoding RNAs (lncRNAs) have emerged as essential regulators of skeletal myogenesis, but few myogenesis-associated lncRNAs have been identified and our understanding of their regulatory mechanisms remains limited, particularly in goat. Here, we identified a novel lncRNA, TCONS_00006810 (named lncR-125b), from our previous lncRNA sequencing data on fetal (45, 60, and 105 days of gestation, three biological replicates for each point) and postnatal (3 days after birth, n = 3) goat skeletal muscle, and found that it is highly expressed in skeletal muscle and gradually upregulated during skeletal muscle satellite cell (SMSC) differentiation in goat. Notably, overexpression of lncR-125b accelerated the expression of myogenic differentiation 1 (MyoD 1) and myogenin (MyoG), and the formation of myotubes, and knockdown of lncR-125b showed opposite effects in SMSCs. Results of dual-luciferase assay and quantitative real-time polymerase chain reaction revealed that lncR-125b acts as a molecular sponge for miR-125b and that insulin-like growth factor 2 (IGF2), a critical regulator of skeletal myogenesis, is a direct target gene of miR-125b. Further analyses showed that lncR-125b negatively regulates miR-125b expression and positively regulates IGF2 expression in SMSCs. Mechanistically, lncR-125b promotes SMSC differentiation by functioning as a competing endogenous RNA (ceRNA) for miR-125b to control IGF2 expression. These findings identify lncR-125b as a novel noncoding regulator of muscle cell differentiation and skeletal muscle development in goat. [ABSTRACT FROM AUTHOR]

Long noncoding RNAs (lncRNAs) play an important role in the thermogenesis and energy storage of brown adipose tissue (BAT). However, knowledge of the cellular transition from BAT to white adipose tissue (WAT) and the potential role of lncRNAs in goat adipose tissue remains largely unknown. In this study, we analyzed the transformation from BAT to WAT using histological and uncoupling protein 1 (UCP1) gene analyses. Brown adipose tissue mainly existed within the goat perirenal fat at 1 day and there was obviously a transition from BAT to WAT from 1 day to 1 year. The RNA libraries constructed from the perirenal adipose tissues of 1 day, 30 days, and 1 year goats were sequenced. A total number of 21,232 lncRNAs from perirenal fat were identified, including 5393 intronic-lncRNAs and 3546 antisense-lncRNAs. Furthermore, a total of 548 differentially expressed lncRNAs were detected across three stages (fold change ≥ 2.0, false discovery rate (FDR) < 0.05), and six lncRNAs were validated by qPCR. Furthermore, trans analysis found lncRNAs that were transcribed close to 890 protein-coding genes. Additionally, a coexpression network suggested that 4519 lncRNAs and 5212 mRNAs were potentially in trans-regulatory relationships (r > 0.95 or r < −0.95). In addition, Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses showed that the targeted genes were involved in the biosynthesis of unsaturated fatty acids, fatty acid elongation and metabolism, the citrate cycle, oxidative phosphorylation, the mitochondrial respiratory chain complex, and AMP-activated protein kinase (AMPK) signaling pathways. The present study provides a comprehensive catalog of lncRNAs involved in the transformation from BAT to WAT and provides insight into understanding the role of lncRNAs in goat brown adipogenesis. [ABSTRACT FROM AUTHOR]

The elaborate interplay of coding and noncoding factors governs muscle growth and development. Here, we reported a mutual activation between long noncoding RNA (lncRNA) H19 and MyoD (myogenic determination gene number 1) in the muscle process. We successfully cloned the two isoforms of goat H19, which were significantly enriched and positively correlated with MyoD transcripts in skeletal muscles or differentiating muscle satellite cells (MuSCs). To systematically screen genes altered by H19, we performed RNA-seq using cDNA libraries of differentiating H19-deficiency MuSCs and consequently anchored MyoD as the critical genes in mediating H19 function. Intriguingly, some transcripts of MyoD and H19 overlapped in the cytoplasm, which was dramatically damaged when the core complementary nucleotides were mutated. Meanwhile, MyoD RNA successfully pulled down H19 in MS2-RIP experiments. Furthermore, HuR could bind both H19 and MyoD transcripts, while H19 or its truncated mutants successfully stabilized MyoD mRNA, with or without HuR deficiency. In turn, novel functional MyoD protein-binding sites were identified in the promoter and exons of the H19 gene. Our results suggest that MyoD activates H19 transcriptionally, and RNA-RNA hybridization is critical for H19-promoted MyoD expression, which extends our knowledge of the hierarchy of regulatory networks in muscle growth. • H19 promotes differentiation of goat skeletal muscle satellite cells (MuSCs). • H19 partially colocalizes with MyoD transcripts. • H19 significantly stabilizes MyoD mRNA. • MyoD activates H19 by binding on its promoter and exons. [ABSTRACT FROM AUTHOR]

Brown and beige adipose thermogenesis are important for newborn mammals to maintain their body temperature. In addition, these thermogenic fats are regulated by multiple molecular interactions. How the long non-coding RNAs (lncRNAs) regulate adipose thermogenesis in newborn mammals upon cold exposure remains unexplored. Here, we identified lncRNAs induced by cold exposure in brown adipose tissue (BAT) of newborn goats and found that lncDGAT2 was enriched in BAT after cold exposure. Functional studies revealed that lncDGAT2 promoted brown and white adipocyte differentiation as well as thermogenic gene expression. Additionally, PRDM4 directly bound the lncDGAT2 promoter to activate the transcription of lncDGAT2 and the PRDM4-lncDGAT2 axis was essential for the brown adipocyte thermogenic gene program. These findings provide evidence for lncRNA and transcription factor regulatory functions in controlling adipose thermogenesis and energy metabolism of newborn goats. [ABSTRACT FROM AUTHOR]