Project description:Biotin labelled miR-206 mimics ('06") and miR-Control mimics ("NC") were used to indentify putative miRNA transcript targets in FAPs form skeletal muscle
Project description:FAPs isolated by FACS from miR-206 KO mice and WT mice were grown in culure and then placed in basal medium (BM) for 48 hours to assess the transcriptomic changes
Project description:To identify putative novel specific targets of miR-34a, miR-122, miR-206 and miR-210, we overexpressed these miRNAs in human Hela cells by transfecting them with synthetic pre-miRNAs or a synthetic “negative” pre-miRNA as control (miR-Neg1). RNA samples were harvested at 48 hours post-transfection and 2 independent experiments were carried out.
Project description:Fibro-adipogenic progenitors (FAPs) are emerging cellular components of the skeletal muscle regenerative environment. The alternative functional phenotype of FAPs - either supportive of muscle regeneration or promoting fibro-adipogenic degeneration - is a key determinant in the pathogenesis of muscular diseases, including Duchenne Muscular Dystrophy (DMD). However, the molecular regulation of FAPs is still unknown. We show here that an "HDAC-myomiR-BAF60 variant network" regulates the functional phenotype of FAPs in dystrophic muscles of mdx mice. Combinatorial analysis of gene expression microarray and genome-wide chromatin remodeling by Nuclease accessibility (NA)-seq revealed that HDAC inhibitors de-repress a "latent" myogenic program in FAPs from dystrophic muscles at early stages of disease progression. In these cells HDAC inhibition promoted the expression of two core components of the myogenic transcriptional machinery, MyoD and BAF60C, and upregulated the myomiRs (miRs) miR-1.2, miR-133 and miR-206, which target two alternative BAF60 variants (BAF60A and B) ultimately leading to the activation of a pro-myogenic program at the expense of the fibro-adipogenic phenotype. By contrast, FAPs from dystrophic muscles at late stages of disease progression displayed resistance to HDACi-induced chromatin remodeling at myogenic loci and fail to activate the pro-myogenic phenotype. These results reveal a previously unappreciated disease stage-specific bipotency of mesenchimal cells within the regenerative environment of dystrophic muscles. Resolution of such bi-potency by epigenetic interventions, such as HDACi, provides the molecular rationale for the in situ reprogramming of target cells to promote therapeutic regeneration of dystrophic muscles. miRNA modulation upon Histone Deacetylase inhibition in Fibro-Adipogenic Progenitors (FAPs) derived from young mdx mice was evaluated by small RNA-sequencing in 2 controls and 2 treated samples
Project description:In response to skeletal muscle injury, adult myogenic stem cells, known as satellite cells, are activated and undergo proliferation and differentiation to regenerate new muscle fibers. The skeletal muscle-specific microRNA, miR-206, is up-regulated in satellite cells following muscle injury, but its role in muscle regeneration has not been defined. Here we show that skeletal muscle regeneration in response to cardiotoxin injury is impaired in mice lacking miR-206. Loss of miR-206 also accelerates and exacerbates the dystrophic phenotype of mdx mice, a model for Duchenne muscular dystrophy. MiR-206 promotes satellite cell differentiation and fusion to form multinucleated myofibers by suppressing a collection of negative regulators of myogenesis. Our findings reveal an essential role for miR-206 in satellite cell differentiation during skeletal muscle regeneration and as a modulator of Duchenne muscular dystrophy.
Project description:In response to skeletal muscle injury, adult myogenic stem cells, known as satellite cells, are activated and undergo proliferation and differentiation to regenerate new muscle fibers. The skeletal muscle-specific microRNA, miR-206, is up-regulated in satellite cells following muscle injury, but its role in muscle regeneration has not been defined. Here we show that skeletal muscle regeneration in response to cardiotoxin injury is impaired in mice lacking miR-206. Loss of miR-206 also accelerates and exacerbates the dystrophic phenotype of mdx mice, a model for Duchenne muscular dystrophy. MiR-206 promotes satellite cell differentiation and fusion to form multinucleated myofibers by suppressing a collection of negative regulators of myogenesis. Our findings reveal an essential role for miR-206 in satellite cell differentiation during skeletal muscle regeneration and as a modulator of Duchenne muscular dystrophy. total RNA obtained from TA muscle of mdx and 3 miR-206 KO; mdx mice at 3 months of age.
Project description:Mongrel dogs of either sex were randomly divided into 2 groups: 1) infection with control lentiviruses group (lenti-control, n = 6), in which control lentiviruses were injected into left superior fat pads;2) only infection with miR-206 overexpressed lentiviruses group (lenti-miR-206, n = 6), in which miR-206 lentiviruses were injected into left superior fat pads. We used microarrays to detail the global programme of mRNA expression underlying miR-206 overexpression and identified distinct classes of up-regulated and down-regulated genes during this process.