V-Maf Musculoaponeurotic Fibrosarcoma Oncogene Homolog G (MAFG)

Globin gene expression is regulated through nuclear factor erythroid-2 (NFE2) elements located in enhancer-like locus control regions positioned many kb upstream of alpha- and beta-gene clusters . NFE2 DNA-binding activity consists of a heterodimer containing a ubiquitous small Maf protein (MafF; MafG; or MafK) and the tissue-restricted protein p45 NFE2. Both subunits are members of the activator protein-1-like superfamily of basic leucine zipper (bZIP) proteins. MAFG forms heterodimers not only with p45, but also with NFE2-related factor 1 (NRF1) and NFE2-related factor 2; these heterodimers bound to NFE2 sites in vitro. In vivo, MAFG/p45 and MAFG/NRF1 heterodimers stimulated transcription from NFE2 sites. Similar results were found with MAFK.