Genomewide approaches for BACH1 target genes in mouse embryonic fibroblasts showed BACH1-Pparg pathway in adipogenesis

Genes Cells. 2016 Jun;21(6):553-67. doi: 10.1111/gtc.12365. Epub 2016 Mar 30.

Abstract

The transcription repressor BTB and CNC homology 1 (BACH1) represses genes involved in heme metabolism and oxidative stress response. BACH1 also suppresses the p53-dependent cellar senescence in primary mouse embryonic fibroblasts (MEFs). To investigate the role of BACH1 in MEF other than its known functions, we carried out a genomewide mapping of binding site for BACH1 and its heterodimer partner MAFK in immortalized MEFs (iMEFs) using chromatin immunoprecipitation and next-generation sequencing technology (ChIP-sequence). The comparative analysis of the ChIP-sequence data and DNA microarray data from Bach1-deficient and wild-type (WT) iMEF showed 35 novel candidate target genes of BACH1. Among these genes, five genes (Pparg, Nfia, Ptplad2, Adcy1 and Ror1) were related with lipid metabolism. Bach1-deficient iMEFs showed increased expression of mRNA and protein of PPARγ, which is the key factor of adipogenesis. These cells also showed a concomitant increase in ligand-dependent activation of PPARγ target genes compared with wild-type iMEFs. Moreover, Bach1-deficient iMEFs efficiently differentiated to adipocyte compared with wild-type cells in the presence of PPARγ ligands. Our results suggest that BACH1 regulates expression of adipocyte-related genes including Pparg and potentiates adipocyte differentiation capacity.

MeSH terms

  • Adipocytes / cytology
  • Adipogenesis*
  • Animals
  • Basic-Leucine Zipper Transcription Factors / genetics
  • Basic-Leucine Zipper Transcription Factors / metabolism*
  • Embryo, Mammalian / metabolism
  • Fibroblasts / metabolism
  • MafK Transcription Factor / metabolism
  • Mice
  • PPAR gamma / genetics
  • Signal Transduction*

Substances

  • Bach1 protein, mouse
  • Basic-Leucine Zipper Transcription Factors
  • MafK Transcription Factor
  • Mafk protein, mouse
  • PPAR gamma