Chimeric genes with the WT and mutant Ha hsp17.6 G1 HSE sequences. Top, Chimeric gene promoter context for the β-glucuronidase (GUS; −533::GUS, Carranco et al., 1999) and LacZ fusions used in this work. The arrows indicate the Ha hsp17.6 G1 and the Cyc1 promoters. The sequences of the Ha hsp17.6 G1 HSE complex are indicated with a black box. The corresponding, unmodified nucleotide sequences for this HSE (WT) are shown (from −110 to −81 from the transcription initiation site of Ha hsp17.6 G1). The core sequences for the HSE pentanucleotide repeats are marked in bold face with crucial DNA contact positions (G or C) underlined. These core repeats are numbered, below the sequence, from 1 to 5. Nucleotide substitutions in the different mutant HSEs are indicated with lowercase letters. The different mutant sequences were substituted for the WT HSE in each chimeric gene promoter context as described in “Materials and Methods.”