Role of FOXA in mitochondrial citrate carrier gene expression and insulin secretion

Biochem Biophys Res Commun. 2009 Jul 24;385(2):220-4. doi: 10.1016/j.bbrc.2009.05.030. Epub 2009 May 13.

Abstract

In this study, we have investigated the transcriptional role of the FOXA site present in the promoter of the mitochondrial citrate carrier (CIC) gene. We have shown that wild-type (but not mutated) CIC FOXA site cloned in front of the luciferase promoter confers transcriptional activation of the gene reporter, particularly in cells overexpressing FOXA1. We have also demonstrated that overexpression and silencing of FOXA increases and reduces CIC transcript and protein levels, respectively. In addition, FOXA1 silencing in INS-1 cells decreases not only CIC mRNA and protein but also the amount of citrate in the cytosol and glucose-stimulated insulin secretion. These results show that FOXA plays a role in the transcriptional regulation of CIC and in insulin secretion.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Anion Transport Proteins / genetics*
  • Base Sequence
  • Binding Sites
  • Cell Line
  • Gene Expression Regulation*
  • Hepatocyte Nuclear Factor 3-alpha / metabolism*
  • Humans
  • Insulin / metabolism*
  • Insulin Secretion
  • Insulin-Secreting Cells / metabolism*
  • Mitochondrial Proteins / genetics*
  • Organic Anion Transporters
  • Transcription, Genetic

Substances

  • Anion Transport Proteins
  • FOXA1 protein, human
  • Hepatocyte Nuclear Factor 3-alpha
  • Insulin
  • Mitochondrial Proteins
  • Organic Anion Transporters
  • Slc25a1 protein, human