miR-434-3p and DNA hypomethylation co-regulate eIF5A1 to increase AChRs and to improve plasticity in SCT rat skeletal muscle

Sci Rep. 2016 Mar 11:6:22884. doi: 10.1038/srep22884.

Abstract

Acetylcholine receptors (AChRs) serve as connections between motor neurons and skeletal muscle and are essential for recovery from spinal cord transection (SCT). Recently, microRNAs have emerged as important potential biotherapeutics for several diseases; however, whether miRNAs operate in the modulation of AChRs remains unknown. We found increased AChRs numbers and function scores in rats with SCT; these increases were reduced following the injection of a eukaryotic translation initiation factor 5A1 (eIF5A1) shRNA lentivirus into the hindlimb muscle. Then, high-throughput screening for microRNAs targeting eIF5A1 was performed, and miR-434-3p was found to be robustly depleted in SCT rat skeletal muscle. Furthermore, a highly conserved miR-434-3p binding site was identified within the mRNA encoding eIF5A1 through bioinformatics analysis and dual-luciferase assay. Overexpression or knockdown of miR-434-3p in vivo demonstrated it was a negative post-transcriptional regulator of eIF5A1 expression and influenced AChRs expression. The microarray-enriched Gene Ontology (GO) terms regulated by miR-434-3p were muscle development terms. Using a lentivirus, one functional gene (map2k6) was confirmed to have a similar function to that of miR-434-3p in GO terms. Finally, HRM and MeDIP-PCR analyses revealed that DNA demethylation also up-regulated eIF5A1 after SCT. Consequently, miR-434-3p/eIF5A1 in muscle is a promising potential biotherapy for SCI repair.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • 3' Untranslated Regions
  • Animals
  • Binding Sites
  • Computational Biology
  • DNA Methylation*
  • Disease Models, Animal
  • Eukaryotic Translation Initiation Factor 5A
  • Gene Expression Profiling
  • Gene Expression Regulation*
  • Gene Ontology
  • MicroRNAs / genetics*
  • Molecular Sequence Annotation
  • Motor Activity
  • Muscle, Skeletal / metabolism*
  • Peptide Initiation Factors / genetics*
  • RNA Interference
  • RNA-Binding Proteins / genetics*
  • Rats
  • Receptors, Nicotinic / genetics*
  • Spinal Cord Injuries / genetics*
  • Spinal Cord Injuries / rehabilitation
  • Transcriptome

Substances

  • 3' Untranslated Regions
  • MicroRNAs
  • Peptide Initiation Factors
  • RNA-Binding Proteins
  • Receptors, Nicotinic