Involved in ABA and stress responses and acts as a positive component of glucose signal transduction. Functions as transcriptional activator in the ABA-inducible expression of rd29B. Binds specifically to the ABA-responsive element (ABRE) of the rd29B gene promoter. DNA-binding heterodimer (By similarity). Interacts with ARIA. A number of isoforms are produced. According to EST sequences. Expressed in roots, leaves, flowers and siliques but not in seeds. Up-regulated by drought, salt, abscisic acid (ABA), cold and glucose. The activation by phosphorylation is induced by abscisic acid (ABA). Phosphorylated by SRK2C, SRK2D, SRK2E, SRK2F and SRK2I in vitro. Defective in glucose response and grows faster. Exhibits abscisic acid (ABA) insensitivity. Belongs to the bZIP family. ABI5 subfamily.