NFATc4 is negatively regulated in miR-133a-mediated cardiomyocyte hypertrophic repression

Am J Physiol Heart Circ Physiol. 2010 May;298(5):H1340-7. doi: 10.1152/ajpheart.00592.2009. Epub 2010 Feb 19.


Activation of NFAT (nuclear factor of activated T cells)-mediated hypertrophic signaling is a major regulatory response to hypertrophic stimuli. A recent study unveiled potential regulatory roles for microRNA-133a (miR-133a) in cardiac hypertrophy. To date, however, no connection has been made between miR-133a and NFAT signaling. In this study, we determined that NFATc4, a hypertrophy-associated mediator, is negatively regulated by miR-133a. Two conserved base-pairing sites between the NFATc4 3'-untranslated region (UTR) and miR-133a were verified. Mutation of these sites in the NFATc4 3'-UTR completely blocked the negative effect of miR-133a on NFATc4, suggesting that NFATc4 is a direct target for miR-133a regulation. Using a gain-of-function approach, we demonstrate that miR-133 significantly reduces the endogenous level of, as well as the hypertrophic stimulus-mediated increase in, NFATc4 gene expression. This latter effect of miR-133a on NFATc4 gene expression was coincided with an attenuated cardiomyocyte hypertrophy induced by an alpha-adrenergic receptor agonist. Conversely, cells treated with miR-133a inhibitor resulted in an increase in NFATc4 expression level. Application of miR-133a had no apparent effect on NFATc4 nuclear localization. We conclude that the negative regulation of NFATc4 expression contributes to miR-133a-mediated hypertrophic repression.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • 3' Untranslated Regions / genetics
  • Adenoviridae / genetics
  • Animals
  • Animals, Newborn
  • Base Sequence
  • Blotting, Western
  • Cardiomegaly / metabolism*
  • Cardiomegaly / pathology
  • Cell Size / drug effects
  • Cells, Cultured
  • Computational Biology
  • Genetic Vectors
  • Immunohistochemistry
  • Luciferases / metabolism
  • Male
  • MicroRNAs / physiology*
  • Myocytes, Cardiac / drug effects*
  • Myocytes, Cardiac / ultrastructure
  • NFATC Transcription Factors / biosynthesis*
  • NFATC Transcription Factors / genetics*
  • Nerve Tissue Proteins / biosynthesis*
  • Nerve Tissue Proteins / genetics*
  • Plasmids / genetics
  • RNA, Messenger / biosynthesis
  • RNA, Messenger / genetics
  • Rats
  • Rats, Sprague-Dawley
  • Reverse Transcriptase Polymerase Chain Reaction
  • Signal Transduction / drug effects


  • 3' Untranslated Regions
  • MIRN133 microRNA, rat
  • MicroRNAs
  • NFATC Transcription Factors
  • Nerve Tissue Proteins
  • Nfatc4 protein, rat
  • RNA, Messenger
  • Luciferases