Co-expression of ase^Scer\UAS.cBa and nvy^Scer\UAS.cWa, both under the control of Scer\GAL4^pnr-MD237, leads to a phenotype that is an intermediate of the two phenotypes seen when each is expressed separately. Resulting larvae have few sensory organ precursors in the wing disc, and adults have some bristles on the thorax. Co-expression of nvy^Scer\UAS.cWa with sc^Scer\UAS.cPa, both under the control of Scer\GAL4^pnr-MD237, results in the same phenotype caused by nvy^Scer\UAS.cWa single expression, in which dorsal thoracic macrochaetae are missing. The extra macrochaetae phenotype caused by sc^Scer\UAS.cPa single expression is completely suppressed. The bristle phenotype of flies co-expressing sens^Scer\UAS.cNa and nvy^Scer\UAS.cWa, both under the control of Scer\GAL4^sca-537.4, is exactly the same as that of flies that only express sens^Scer\UAS.cNa; there are extra bristles present on the thorax. Co-expression of da^Scer\UAS.cGa and nvy^Scer\UAS.cWa, both under the control of Scer\GAL4^pnr-MD237, causes a bristle phenotype that is intermediate to the two phenotypes produced by single expression of either; flies have fewer macrochaetae on the thorax than wild type.