Function
Transcription activator that binds DNA to the C-box-like motif (5'-TGCTGACGTCA-3'), ABRE elements, G-box-like motif (5'-CCACGTGGCC-3'), DOF (5'-AAAG-3'), I-box (5'-GATAA-3'), BS1 (5'-AGCGGG-3'), MY3 (5'-CGACG-3'), 5'-CAGTGCGC-3' and 5'-ACTCAT-3' sequence in target gene promoters (PubMed:15047879, PubMed:16810321, PubMed:19531597, PubMed:21278122, PubMed:25108460). DNA-binding and subsequent transcription activation is triggered by heterodimerization with other bZIP proteins (e.g. BZIP1, BZIP10 and BZIP25) (PubMed:16810321, PubMed:19531597, PubMed:21278122). Promotes POX1/PRODH1 expression in response to hypoosmolarity stress (PubMed:15047879, PubMed:16810321). Transcriptional activator of seed maturation (MAT) genes (e.g. AT2S2), including seed storage protein (SSP) and late embryogenesis abundant (LEA) genes (PubMed:19531597). Activated by low energy stress both by transcriptional and post-transcriptional mechanisms. Promotes dark-induced senescence and participates in the transcriptional reprogramming of amino acid metabolism during the dark-induced starvation response, especially when heterodimerized with BZIP1, by triggering accumulation of sepcific proteins including ASN1 and POX1/PRODH1 (PubMed:21278122).