Salivary gland-specific binding assays reveal that CrebA, a bZIP transcription factor, directly binds the vast majority of genes encoding the secretory machinery, including proteins of the signal recognition particle and receptor, proteins involved in co-translational import of cargo into the ER, proteins involved in vesicular transport between the ER and Golgi, as well as the structural proteins and enzymes of these organelles. CrebA does not bind salivary gland-specific cargo genes. Instead, it binds and boosts expression of Sage, which encodes a bHLH transcription factor that upregulates cargo expression. CrebA also directly binds and upregulates Xbp1, which encodes a key factor in the unfolded protein response, and Tudor-SN, which encodes a protein that in other systems increases secretory cargo mRNA levels. Overall design: CrebA is expressed in multiple Drosophila embryonic tissues, including the salivary gland (SG), proventriculus, trachea, and epidermis. Thus, we employed the Gal4/UAS system to express C-terminal GFP-tagged CrebA (CrebA-GFP) for ChIP-Seq to identify SG-specific in vivo CrebA binding sites using a well-characterized GFP antibody that has been used extensively for ChIP-Seq studies of Drosophila TFs. Two Gal4 drivers were used, fkh-Gal4 and sage-Gal4; both drive UAS-transgene expression in multiple tissues, but have only SG expression in common. Whole embryo ChIP using CrebA antiserum was also performed on wild-type animals (Oregon R).