Increased FOG-2 in failing myocardium disrupts thyroid hormone-dependent SERCA2 gene transcription

Circ Res. 2008 Aug 29;103(5):493-501. doi: 10.1161/CIRCRESAHA.108.181487. Epub 2008 Jul 25.

Abstract

Reduced expression of sarcoplasmic reticulum calcium ATPase (SERCA)2 and other genes in the adult cardiac gene program has raised consideration of an impaired responsiveness to thyroid hormone (T3) that develops in the advanced failing heart. Here, we show that human and murine cardiomyopathy hearts have increased expression of friend of GATA (FOG)-2, a cardiac nuclear hormone receptor corepressor protein. Cardiac-specific overexpression of FOG-2 in transgenic mice led to depressed cardiac function, activation of the fetal gene program, congestive heart failure, and early death. SERCA2 transcript and protein levels were reduced in FOG-2 transgenic hearts, and FOG-2 overexpression impaired T3-mediated SERCA2 expression in cultured cardiomyocytes. FOG-2 physically interacts with thyroid hormone receptor-alpha1 and abrogated even high levels of T3-mediated SERCA2 promoter activity. These results demonstrate that SERCA2 is an important target of FOG-2 and that increased FOG-2 expression may contribute to a decline in cardiac function in end-stage heart failure by impaired T3 signaling.

Publication types

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

MeSH terms

  • Animals
  • Cardiomyopathies / diagnostic imaging
  • Cardiomyopathies / metabolism
  • Cardiomyopathies / physiopathology
  • Cell Line
  • DNA-Binding Proteins / genetics*
  • DNA-Binding Proteins / metabolism*
  • Echocardiography
  • Heart Failure / diagnostic imaging
  • Heart Failure / metabolism
  • Heart Failure / physiopathology*
  • Humans
  • Kidney / cytology
  • Mice
  • Mice, Inbred ICR
  • Mice, Transgenic
  • Myocytes, Cardiac / cytology
  • Oligonucleotide Array Sequence Analysis
  • Phenotype
  • Promoter Regions, Genetic / physiology
  • Rats
  • Sarcoplasmic Reticulum Calcium-Transporting ATPases / genetics*
  • Sarcoplasmic Reticulum Calcium-Transporting ATPases / metabolism
  • Signal Transduction / physiology
  • Thyroid Hormone Receptors alpha / metabolism
  • Transcription Factors / genetics*
  • Transcription Factors / metabolism*
  • Transcription, Genetic / physiology
  • Transfection
  • Triiodothyronine / metabolism*

Substances

  • DNA-Binding Proteins
  • Thyroid Hormone Receptors alpha
  • Transcription Factors
  • Zfpm2 protein, mouse
  • Triiodothyronine
  • Sarcoplasmic Reticulum Calcium-Transporting ATPases
  • ATP2A2 protein, human
  • Atp2a2 protein, mouse