miR-486 is an epigenetic modulator of Duchenne muscular dystrophy pathologies

Duchenne muscular dystrophy (DMD) is an X-linked progressive muscle disorder resulting in muscle weakness and cardiomyopathy. MicroRNAs have been shown to play essential roles in muscle development, metabolism, and disease pathologies. We demonstrated that miR-486 expression is reduced in DMD muscles and its expression levels correlate with dystrophic disease severity. MicroRNA-486 knockout mice developed disrupted myofiber architecture, decreased myofiber size, decreased locomotor activity, increased cardiac fibrosis, and metabolic defects that were exacerbated on the dystrophic mdx5cv background. We integrated RNA-sequencing and chimeric eCLIP-sequencing data to identify direct in vivo targets of miR-486 and associated dysregulated gene signatures in skeletal muscle. In comparison to our DMD mouse muscle transcriptomes, we identified several of these miR-486 muscle targets including known modulators of dystrophinopathy disease symptoms. Together, our studies identify miR-486 as a driver of muscle remodeling in DMD, a useful biomarker for dystrophic disease progression, and highlight chimeric eCLIP-sequencing as a useful tool to identify direct in vivo microRNA target transcripts. O_FIG O_LINKSMALLFIG WIDTH=122 HEIGHT=200 SRC="FIGDIR/small/448387v1_ufig1.gif" ALT="Figure 1"> View larger version (61K): org.highwire.dtl.DTLVardef@13eeaf5org.highwire.dtl.DTLVardef@1b3b2dborg.highwire.dtl.DTLVardef@a36782org.highwire.dtl.DTLVardef@1e0b95f_HPS_FORMAT_FIGEXP M_FIG C_FIG