Transcription factor that binds to the 5'-ACGT-3' box, especially present in G-box-like motif (5'-CCACGTGGCC-3'), ABRE elements, of seed storage protein (SSP) encoding gene promoters (e.g. At2S and CRU3) and promotes their expression in seeds when in complex with ABI3 and BZIP53. Homodimer (Probable). Forms a heterodimer with BZIP1, BZIP1, BZIP2, BZIP9, BZIP11, BZIP44, BZIP53 and BZIP63. Interacts with ABI3 and forms a complex made of ABI3, BZIP53 and BZIP25. Expressed in roots, shoots, stems, leaves, stipulae, siliques, seeds, pollen, and flowers. First observed in seeds at early stages of development, mostly in embryo and, at lower extent, in the endosperm. Accumulates and peaks at maturation. Fade out during late seed development steps, restricted to the inner layer of the seed coat, and, at very low levels, in the mature embryo and the remaining endosperm. Also present in the lignified inner subepidermal layer of the valves. Belongs to the bZIP family.