Nrf2-MafG heterodimers contribute globally to antioxidant and metabolic networks

Nucleic Acids Res. 2012 Nov 1;40(20):10228-39. doi: 10.1093/nar/gks827. Epub 2012 Sep 10.

Abstract

NF-E2-related factor 2 (Nrf2) is a key transcription factor that is critical for cellular defense against oxidative and xenobiotic insults. Nrf2 heterodimerizes with small Maf (sMaf) proteins and binds to antioxidant response elements (AREs) to activate a battery of cytoprotective genes. However, it remains unclear to what extent the Nrf2-sMaf heterodimers contribute to ARE-dependent gene regulation on a genome-wide scale. We performed chromatin immunoprecipitation coupled with high-throughput sequencing and identified the binding sites of Nrf2 and MafG throughout the genome. Compared to sites occupied by Nrf2 alone, many sites co-occupied by Nrf2 and MafG exhibit high enrichment and are located in species-conserved genomic regions. The ARE motifs were significantly enriched among the recovered Nrf2-MafG-binding sites but not among the Nrf2-binding sites that did not display MafG binding. The majority of the Nrf2-regulated cytoprotective genes were found in the vicinity of Nrf2-MafG-binding sites. Additionally, sequences that regulate glucose metabolism and several amino acid transporters were identified as Nrf2-MafG target genes, suggesting diverse roles for the Nrf2-MafG heterodimer in stress response. These data clearly support the notion that Nrf2-sMaf heterodimers are complexes that regulate batteries of genes involved in various aspects of cytoprotective and metabolic functions through associated AREs.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antioxidants / metabolism*
  • Binding Sites
  • Cell Line, Tumor
  • Gene Expression Regulation* / drug effects
  • Gene Expression Regulation, Enzymologic
  • Gene Regulatory Networks
  • Genome
  • MafG Transcription Factor / genetics
  • MafG Transcription Factor / metabolism*
  • Maleates / pharmacology
  • Mice
  • Mice, Knockout
  • NADP / metabolism
  • NF-E2-Related Factor 2 / metabolism*
  • Repressor Proteins / genetics
  • Repressor Proteins / metabolism*
  • Response Elements

Substances

  • Antioxidants
  • MafG Transcription Factor
  • Mafg protein, mouse
  • Maleates
  • NF-E2-Related Factor 2
  • Nfe2l2 protein, mouse
  • Repressor Proteins
  • NADP
  • diethyl maleate