Transcriptional activator that binds specifically to the DNA sequence 5'-TGACG-3'. Recognizes ocs elements like the as-1 motif of the cauliflower mosaic virus 35S promoter. Binding to the as-1-like cis elements mediate auxin- and salicylic acid-inducible transcription. May be involved in the induction of the systemic acquired resistance (SAR) via its interaction with NPR1. Could also bind to the Hex-motif (5'-TGACGTGG-3') another cis-acting element found in plant histone promoters. Binds DNA as a dimer. The reduced form interacts with NPR1. A number of isoforms are produced. According to EST sequences. Predominantly expressed in roots. Belongs to the bZIP family.