The P{Mae-UAS.E} element contains UAS regulatory sequences (with no promoter sequence) at its 3' end, oriented outwards. A set of GAGA binding sites are inserted upstream of the UAS sequences to prevent position effects. A w^+mC marker is present at the 5' end of the element. Of 76 insertions, none exhibited a mutant phenotype, implying that UAS activating elements without adjacent promoter sequences fail to elicit expression from proximate genes when inserted in the genome.