MicroRNA-124 regulates neuronal differentiation of mesenchymal stem cells by targeting Sp1 mRNA

J Cell Biochem. 2015 Jun;116(6):943-53. doi: 10.1002/jcb.25045.

Abstract

MicroRNAs play an important role in neuronal development and function. miR-124 is the most abundantly expressed miRNA in the nervous system. Several different mRNA targets have been proposed for miR-124, but the precise function of endogenous miR-124 and its mRNA targets remain to be further elucidated. Specificity protein 1 (Sp1) is a transcription factor that plays key roles in many cell processes including cell cycle. However, this transcription factor is nearly absent in differentiated neurons and a remarkable suppression of Sp1 expression was shown after neurogenesis. Since miR-124 is expressed abundantly in neurons and because Sp1 levels decrease during neurogenesis, it is possible that miR-124 could regulate the expression of Sp1 during neuronal development. Therefore, the aim of the present study was to evaluate the putative targeting of Sp1 by miR-124. Overexpression of miR-124 using a plasmid coding for pri-miR-124 in HEK293 cells decreased the expression of Sp1 mRNA. The results of dual-luciferase reporter assay demonstrated that miR-124 directly targeted the 3'-untranslated regions of Sp1 mRNA. To evaluate whether Sp1 expression was regulated by miR-124 during the process of neuronal differentiation, Adipose-derived mesenchymal stem cells (A-MSCs) were differentiated into neuron-like cells. The results of qPCR analysis showed that with the gradual increase of miR-124 expression during neurogenesis, the expression of Sp1 mRNA decreased accordingly. In summary, this study demonstrated for the first time that miR-124 is able to suppress Sp1 expression, which in turn affected the neuronal differentiation of mesenchymal stem cells.

Keywords: CELL DIFFERENTIATION; MicroRNAs; NEUROGENESIS; SPECIFIC PROTEIN 1; miR-124.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cell Differentiation / genetics
  • Cell Differentiation / physiology
  • HEK293 Cells
  • Humans
  • Mesenchymal Stem Cells / metabolism*
  • MicroRNAs / genetics
  • MicroRNAs / metabolism*
  • RNA, Messenger / genetics*
  • Reverse Transcriptase Polymerase Chain Reaction
  • Sp1 Transcription Factor / genetics*

Substances

  • MIRN124 microRNA, human
  • MicroRNAs
  • RNA, Messenger
  • Sp1 Transcription Factor