Translational control of FOG-2 expression in cardiomyocytes by microRNA-130a

PLoS One. 2009 Jul 7;4(7):e6161. doi: 10.1371/journal.pone.0006161.

Abstract

MicroRNAs are increasingly being recognized as regulators of embryonic development; however, relatively few microRNAs have been identified to regulate cardiac development. FOG-2 (also known as zfpm2) is a transcriptional co-factor that we have previously shown is critical for cardiac development. In this report, we demonstrate that FOG-2 expression is controlled at the translational level by microRNA-130a. We identified a conserved region in the FOG-2 3' untranslated region predicted to be a target for miR-130a. To test the functional significance of this site, we generated an expression construct containing the luciferase coding region fused with the 3' untranslated region of FOG-2 or a mutant version lacking this microRNA binding site. When these constructs were transfected into NIH 3T3 fibroblasts (which are known to express miR-130a), we observed a 3.3-fold increase in translational efficiency when the microRNA target site was disrupted. Moreover, knockdown of miR-130a in fibroblasts resulted in a 3.6-fold increase in translational efficiency. We also demonstrate that cardiomyocytes express miR-130a and can attenuate translation of mRNAs with a FOG-2 3' untranslated region. Finally, we generated transgenic mice with cardiomyocyte over-expression of miR-130a. In the hearts of these mice, FOG-2 protein levels were reduced by as much as 80%. Histological analysis of transgenic embryos revealed ventricular wall hypoplasia and ventricular septal defects, similar to that seen in FOG-2 deficient hearts. These results demonstrate the importance of miR-130a for the regulation of FOG-2 protein expression and suggest that miR-130a may also play a role in the regulation of cardiac development.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • 3' Untranslated Regions
  • Animals
  • DNA-Binding Proteins / genetics*
  • Gene Expression Regulation / physiology*
  • Mice
  • Mice, Transgenic
  • MicroRNAs / physiology*
  • Myocardium / cytology
  • Myocardium / metabolism*
  • NIH 3T3 Cells
  • Protein Biosynthesis*
  • Transcription Factors / genetics*

Substances

  • 3' Untranslated Regions
  • DNA-Binding Proteins
  • MicroRNAs
  • Transcription Factors
  • Zfpm2 protein, mouse