This family of proteins is found in eukaryotes. Proteins in this family are typically between 174 and 411 amino acids in length. The family is found in association with pfam00170. There is a conserved KVK sequence motif. There is a single completely conserved residue K that may be functionally important. Various bZIP proteins have been found and shown to play a role in seed-specific gene expression. bZIP binds to the alpha-globulin gene promoter, but not to promoters of other major storage genes such as glutelin, prolamin and albumin.