In vivo detection of regulatory factor binding sites in the 5' flanking region of maize Adh1.

In vivo dimethyl sulfate footprinting experiments have been used to locate the binding sites of regulatory molecules in the TATA proximal portion of the maize alcohol dehydrogenase-1 gene. In several tissues and organs, Adh1 is transcriptionally induced by anaerobic stress, and the various alleles of Adh1 can show a quantitative differential response to induction. Two regulatory molecules were found to be bound to the promoter only when the gene was induced. The binding sites for these factors mapped to regions located at -100 to -108 and -186 to -190 relative to the site of transcript initiation. Two additional regulatory molecules were bound to sites located at positions -117 to -120 and -138 to -145 regardless of the state of transcription. However, the factor bound at the -138 to -145 region was found to alter its binding characteristics when the gene was induced.