Predictive base substitution rules that determine the binding and transcriptional specificity of Maf recognition elements

• DOI: 10.1111/j.1365-2443.2006.00965.x
• Publication Date: 2006-04-27T14:10:59Z
• Authors: Tae Yamamoto; Motoki Kyo; Terue Kamiya; Toshiyuki Tanaka; James Douglas Engel; Hozumi Motohashi; Masayuki Yamamoto
• Keywords: Transcription

Small Maf transcription factors possess a basic region‐leucine zipper motif through which they form homodimers or heterodimers with CNC and Bach proteins. Different combinations of small CNC/Bach protein dimers bind to cis ‐acting DNA elements, collectively referred as Maf‐recognition elements (MAREs), either activate repress transcription. As MAREs defined by function are often divergent from the consensus sequence, we speculated that sequence variations in basis for selective Maf:Maf Maf:CNC dimer binding. To test this hypothesis, analyzed binding Maf‐containing variant sequences MARE using bacterially expressed MafG Nrf2 proteins surface plasmon resonance‐microarray imaging technique. We found base substitutions actually determined their preference different dimers. In fact, were able categorize into five groups: homodimer‐orientd (Groups I II), ambivalent (Group III), MafG:Nrf2 heterodimer‐orientd IV), silent V). This study thus manifests clear set rules pertaining element determine whether given preferentially associates homodimer heterodimer.