The R9C11 enhancer is fused upstream of the Drosophila synthetic core promoter (DSCP), followed by a GAL4::VP16 driver composed of DNA-binding domain (amino acids 1-147) fused to the VP16 activation domain (amino acids 413-490). The entire coding region has been optimised for Drosophila codon usage. An Hsp70 transcriptional terminator is present.