MicroRNAs(miRNAs)have been demonstrated to control chicken skeletal muscle growth,however,the potential function of the miR-181-5p family in chicken myogenesis remains largely unknown.Here,our study identified the two...MicroRNAs(miRNAs)have been demonstrated to control chicken skeletal muscle growth,however,the potential function of the miR-181-5p family in chicken myogenesis remains largely unknown.Here,our study identified the two chicken(Gallus gallus;Gga)miR-181-5p family members widely expressed in various tissues,specifically miR-181a-5p and miR-181b-5p.Besides,the breast muscles of fast-growing broilers expressed higher levels of miR-181a-5p and miR-181b-5p than those of slow-growing layers.Functionally,miR-181a-5p and miR-181b-5p both promote the expression level of myogenic factors including myogenin(MyoG),myogenic differentiation 1(MyoD1),and myosin heavy chain(MyHC),meanwhile accelerating the myotube formation of skeletal muscle satellite cells(SMSCs).Mechanistically,miR-181a-5p and miR-181b-5p directly bind to the 3′untranslated region(UTR)of the transforming growth factor beta receptor 1(TGFBR1)mRNA,further reducing the expression of TGFBR1.TGFBR1 is a key Transforming growth factor beta(TGF-β)signaling transduction receptor and had a negative function in muscle cell differentiation.Furthermore,knockdown of TGFBR1 facilitated the expression of chicken myogenic factors,boosted myotube formation,and decreased the SMAD family member 2/3(SMAD2/3)phosphorylation in chicken SMSCs.SMAD2/3 are downstream of TGF-βsignaling,and miR-181a-5p and miR-181b-5p could reduce the expression of TGFBR1 to further diminish the SMAD2/3 phosphorylation.Our findings revealed that the miR-181-5p family targets TGFBR1 to break the TGF-βsignaling transduction,which resulted in promoting chicken skeletal muscle development.展开更多
Objective: To explore the mechanism by which ghrelin regulates insulin sensitivity through modulation of miR-455-5p in hepatic cells. Methods: HepG2 cells were treated with or without DAG (1 μM). Glucose consumption,...Objective: To explore the mechanism by which ghrelin regulates insulin sensitivity through modulation of miR-455-5p in hepatic cells. Methods: HepG2 cells were treated with or without DAG (1 μM). Glucose consumption, intracellular glycogen content, phosphorylation of PI3K and Akt stimulated by insulin, expression of miR-455-5p, as well as IGF-1R protein level were analyzed. In addition, bioinformatic analysis, dual luciferase reporter assay, miR- 455-5p mimic or inhibitor treatment was conducted to investigate the molecular mechanisms. Results: High glucose treatment upregulated miR-455-5p expression but reduced glucose consumption and glycogen content. DAG reversed the effect of high glucose on glucose metabolism, increased protein level of IGF-1R and phosphorylation of PI3K/Akt stimulated by insulin, as well as downregulated miR-455-5p expression. Bioinformatic analysis indicated IGF-1R was the target of miR-455-5p. Dual luciferase reporter assay, as well as transfection with miR-455-5p mimic/inhibitor confirmed that DAG activated IGF-1R/PI3K/Akt signaling via inhibiting miR-455-5p. Conclusion: DAG improves insulin resistance via miR-455-5p- mediated activation of IGF-1R/PI3K/Akt system, suggesting that suppression of miR-455-5p or activation of DAG may be potential targets for T2DM therapy.展开更多
基金supported by the National Key Research and Development Program of China(2022YFF10002020)Sichuan Science and Technology Program,China(2021YFYZ0007 and 2021YFYZ0031).
文摘MicroRNAs(miRNAs)have been demonstrated to control chicken skeletal muscle growth,however,the potential function of the miR-181-5p family in chicken myogenesis remains largely unknown.Here,our study identified the two chicken(Gallus gallus;Gga)miR-181-5p family members widely expressed in various tissues,specifically miR-181a-5p and miR-181b-5p.Besides,the breast muscles of fast-growing broilers expressed higher levels of miR-181a-5p and miR-181b-5p than those of slow-growing layers.Functionally,miR-181a-5p and miR-181b-5p both promote the expression level of myogenic factors including myogenin(MyoG),myogenic differentiation 1(MyoD1),and myosin heavy chain(MyHC),meanwhile accelerating the myotube formation of skeletal muscle satellite cells(SMSCs).Mechanistically,miR-181a-5p and miR-181b-5p directly bind to the 3′untranslated region(UTR)of the transforming growth factor beta receptor 1(TGFBR1)mRNA,further reducing the expression of TGFBR1.TGFBR1 is a key Transforming growth factor beta(TGF-β)signaling transduction receptor and had a negative function in muscle cell differentiation.Furthermore,knockdown of TGFBR1 facilitated the expression of chicken myogenic factors,boosted myotube formation,and decreased the SMAD family member 2/3(SMAD2/3)phosphorylation in chicken SMSCs.SMAD2/3 are downstream of TGF-βsignaling,and miR-181a-5p and miR-181b-5p could reduce the expression of TGFBR1 to further diminish the SMAD2/3 phosphorylation.Our findings revealed that the miR-181-5p family targets TGFBR1 to break the TGF-βsignaling transduction,which resulted in promoting chicken skeletal muscle development.
基金Changshu Science and Technology Plan(Social Development)Project(No.CS202130)Key Project of Changshu No.2 People’s Hospital(No.CSEY2021007)。
文摘Objective: To explore the mechanism by which ghrelin regulates insulin sensitivity through modulation of miR-455-5p in hepatic cells. Methods: HepG2 cells were treated with or without DAG (1 μM). Glucose consumption, intracellular glycogen content, phosphorylation of PI3K and Akt stimulated by insulin, expression of miR-455-5p, as well as IGF-1R protein level were analyzed. In addition, bioinformatic analysis, dual luciferase reporter assay, miR- 455-5p mimic or inhibitor treatment was conducted to investigate the molecular mechanisms. Results: High glucose treatment upregulated miR-455-5p expression but reduced glucose consumption and glycogen content. DAG reversed the effect of high glucose on glucose metabolism, increased protein level of IGF-1R and phosphorylation of PI3K/Akt stimulated by insulin, as well as downregulated miR-455-5p expression. Bioinformatic analysis indicated IGF-1R was the target of miR-455-5p. Dual luciferase reporter assay, as well as transfection with miR-455-5p mimic/inhibitor confirmed that DAG activated IGF-1R/PI3K/Akt signaling via inhibiting miR-455-5p. Conclusion: DAG improves insulin resistance via miR-455-5p- mediated activation of IGF-1R/PI3K/Akt system, suggesting that suppression of miR-455-5p or activation of DAG may be potential targets for T2DM therapy.
