Probable transcription factor that acts as a positive regulator of ABA-responsiveness, mediating the inhibitory effect of ABA on growth during seedling establishment. Binds to the DNA sequence 5'-CAATNATTG-3'. Interacts with DNA as homodimer. A number of isoforms are produced. According to EST sequences. Widely expressed. Localized primarily to the hypocotyl of germinating seedlings. Down-regulated by abscisic acid (ABA) and by salt stress. Belongs to the HD-ZIP homeobox family. Class I subfamily.