MicroRNA-mRNA Profile of Skeletal Muscle Differentiation and Relevance to Congenital Myotonic Dystrophy.

Sarah U Morton,Michael D Uhler,David L Turner,Pankaj B Agrawal,Huanqing Zhang,Manhong Dai,Christopher R Sefton

doi:10.3390/ijms22052692

Abstract

microRNAs (miRNAs) regulate messenger RNA (mRNA) abundance and translation during key developmental processes including muscle differentiation. Assessment of miRNA targets can provide insight into muscle biology and gene expression profiles altered by disease. mRNA and miRNA libraries were generated from C2C12 myoblasts during differentiation, and predicted miRNA targets were identified based on presence of miRNA binding sites and reciprocal expression. Seventeen miRNAs were differentially expressed at all time intervals (comparing days 0, 2, and 5) of differentiation. mRNA targets of differentially expressed miRNAs were enriched for functions related to calcium signaling and sarcomere formation. To evaluate this relationship in a disease state, we evaluated the miRNAs differentially expressed in human congenital myotonic dystrophy (CMD) myoblasts and compared with normal control. Seventy-four miRNAs were differentially expressed during healthy human myocyte maturation, of which only 12 were also up- or downregulated in CMD patient cells. The 62 miRNAs that were only differentially expressed in healthy cells were compared with differentiating C2C12 cells. Eighteen of the 62 were conserved in mouse and up- or down-regulated during mouse myoblast differentiation, and their C2C12 targets were enriched for functions related to muscle differentiation and contraction.

Highlights

MicroRNAs are 21- to 22-nucleotide RNAs that function in post-transcriptional regulation of gene expression [1]. miRNAs modulate gene expression by binding to 30 untranslated regions (UTRs) of messenger RNA (mRNA) and recruiting protein complexes that modulate target mRNA abundance or translational efficiency [2]
Mice lacking miR-206 develop a muscular dystrophy phenotype with decreased bulk, muscle fibrosis, and fatty infiltrate [9]. miR-208a/b and miR-499 are necessary for muscle fiber type determination: overexpression of these miRNAs causes total conversion to slow twitch fibers while depletion leads to loss of slow twitch fibers [10]
We identified miRNAs and mRNAs that are up- or down-regulated during myoblast differentiation to myocytes

Summary

Introduction

MicroRNAs are 21- to 22-nucleotide RNAs that function in post-transcriptional regulation of gene expression [1]. miRNAs modulate gene expression by binding to 30 untranslated regions (UTRs) of mRNA and recruiting protein complexes that modulate target mRNA abundance or translational efficiency [2]. MiRNAs modulate gene expression by binding to 30 untranslated regions (UTRs) of mRNA and recruiting protein complexes that modulate target mRNA abundance or translational efficiency [2]. Their effects on protein expression have been implicated in the regulation of a wide range of biological functions and diseases [3,4,5]. MyomiRs, including, miR-1, miR-133a, miR-206, miR-208a/b, and miR-499, are important for muscle development [8]. Mice lacking miR-206 develop a muscular dystrophy phenotype with decreased bulk, muscle fibrosis, and fatty infiltrate [9].

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Conclusion