The miniGAL4(2) driver encodes a transcriptional activator that corresponds to a form of the Saccharomyces cerevisiae GAL4 gene ( SGDID:S000006169 ) with an internal deletion. It consists of GAL4 amino acid residues 1-209 (includes the DNA-binding domain) fused to GAL4 amino acids 717-881 (includes transcriptional activation sequence and the sequence targeted by the GAL80 suppressor) (PMID:9111323). The GAL4 DNA-binding domain binds specifically to the UAS regulatory sequence, and thus miniGAL4(2) and UAS form a binary expression system that can be used to control the spatial and temporal expression of a gene of interest: a transgene or modified endogenous locus carrying the target gene of interest downstream of UAS sequences is combined with a second transgene or modified endogenous locus encoding the miniGAL4(2) driver. miniGAL4(2) has reduced transcriptional activator activity (approximately 50%) compared to the full length GAL4 protein when assayed in Saccharomyces cerevisiae (PMID:9111323).