Evaluation of MafG interaction with Maf recognition element arrays by surface plasmon resonance imaging technique

Abstract

Specific interactions between transcription factors and cis -acting DNA sequence motifs are primary events for the transcriptional regulation. Many regulatory elements appear to diverge from the most optimal recognition sequences. To evaluate affinities of a transcription factor to various suboptimal sequences, we have developed a new detection method based on the surface plasmon resonance (SPR) imaging technique. Transcription factor MafG and its recognition sequence MARE ( Ma f r ecognition e lements) were adopted to evaluate the new method. We modified DNA immobilization procedure on to the gold chip, so that a double-stranded DNA array was successfully fabricated. We further found that a hydrophilic flexible spacer composed of the poly (ethylene glycol) moiety between DNA and alkanethiol self-assembled monolayers on the surface is effective for preventing nonspecific adsorption and facilitating specific binding of MafG. Multiple interaction profiles between MafG and six of MARE-related sequences were observed by the SPR imaging technique. The kinetic values obtained by SPR imaging showed very good correlation with those obtained from electrophoretic gel mobility shift assays, although absolute values were deviated from each other. These results demonstrate that the double-stranded DNA array fabricated with the modified multistep procedure can be applied for the comprehensive analysis of the transcription factor-DNA interaction.

Wearing Red for Signaling: The Heme-Bach Axis in Heme Metabolism, Oxidative Stress Response and Iron Immunology

“…6A), which allows for the binding of the heterodimers of Bach-small Maf, NF-E2 and Nrf-small Maf as well as Maf homodimers in addition to AP-1 (Mignotte 1989a; Ney et al 1990b; Kataoka et al 1994;Oyake et al 1996;Motohashi et al 2000;Kyo et al 2004). Within the heterodimers of small Maf proteins, small Maf recognizes the longer half of the sequence.…”

Discovery and verification of functional single nucleotide polymorphisms in regulatory genomic regions: Current and developing technologies

“…protein-protein interaction) [53], DNA: DNA or DNA:RNA oligomerization [54][55][56][57] and DNA-protein interactions [58][59][60][61]. DNA microarray technology has been combined with SPR imaging analysis to create a medium to high-throughput methodology for quantifying DNA-protein interactions [62] in which a recently modified DNA array generation process has enhanced detection of interactions with double-stranded sequences of similar makeup (i.e., SNPs in binding regions) [63]. Indeed, this technique demonstrated quantifiable differences in binding association and dissociation of competing MafG homodimer or MafG:Nrf2 heterodimer transcription factors to systematic mutations of a Maf recognition element (MARE) sequence using single or double base substitutions in its flanking and core binding regions [61].…”

Bach1 Deficiency Ameliorates Hepatic Injury in a Mouse Model

“…Furthermore, heme induces polyubiquitination and subsequent degradation of Bach1 (Zenke-Kawasaki et al 2007). MARE or MARE-like sequences are present in regulatory regions of various genes that are related to heme, oxidative stress response, and xenobiotics metabolism (Kyo et al 2004). One of the well characterized target genes of Bach1 is Hmox-1 that encodes heme oxygenase-1 (HO-1).…”