Transcriptional activator. Binds to fat body-specific enhancers of alcohol dehydrogenase (ADH) and yolk protein genes. BBF-2 may play a role in fat body gene expression. It binds the consensus sequence 5'-T[AC]NACGTAN[TG]C-3'. May bind DNA as heterodimers with other bZIP proteins. In all cell types examined, including developing salivary gland in embryos and in adults, brain and optic lobe cell bodies, salivary gland, midgut epithelial cells of the cardia, female ovarian columnar follicle cells and male seminal vesicle, ejaculatory duct, and ejaculatory bulb. Present throughout development. Belongs to the bZIP family. Intron retention.