Two enhancer fragments drive GAL4 expression. One is an 8.5 kb BamHI-EcoRI fragment encompassing the first exon and intron of Scr. The second is a 0.8 kb XbaI-HindIII fragment originating in the region between Scr and ftz. These positive regulatory elements are depicted in Figure 7 of Gindhart et al (FBrf0080052). The order of elements in the construct is 0.8 kb-8.5 kb-GAL4.
ScerGAL4Scr.1 drives expression in the embryonic labial and T1 segments, and in the anterior midgut.