The GAL4(DBD) entry in FlyBase represents sequence from the Saccharomyces cerevisiae GAL4 gene ( SGDID:S000006169 ) that includes the DNA-binding domain but does not include the transcriptional activation domain. GAL4(DBD) binds specifically to the UAS sequence (reviewed in FBrf0233764). If a protein of interest is tagged with GAL4(DBD), then that protein can be 'tethered' to copies of UAS that have been inserted into the genome. This property can be used to study the effect of the tagged protein of interest on chromosome organization and/or gene expression. The exact sequence of GAL4(DBD) may differ depending on the particular transgene or modified endogenous locus being used, for example, the coding sequence may have been codon optimized for use in different species.