Expression of Hsap\MADH4^{100T.Scer\UAS} strongly throughout the wing blade (e.g. under the control of Scer\GAL4^Bx-MS1096, Scer\GAL4^C-765 or Scer\GAL4^T80) leads to ectopic mechanosensory bristles on the blade. These appear to be largely derived from the transformation of normally 'bristle-less' campaniform sensilla. The most frequent transformation observed is that of Twin Sensillum One into a mechanosensory bristle.

A mechanosensory bristle is sometimes observed on the ventral surface of the L3 wing vein in Hsap\MADH4^{100T.Scer\UAS}/Scer\GAL4^Bx-MS1096 mutant wings. The second most frequent transformation in Hsap\MADH4^{100T.Scer\UAS}/Scer\GAL4^Bx-MS1096 mutant wings is that of a thin mechanosensory bristle replacing either the proximal, middle, or distal sensillum, at roughly equal frequencies. The most posterior ectopic bristle is rare on a Hsap\MADH4^{100T.Scer\UAS}/Scer\GAL4^Bx-MS1096 mutant wing, and is located on the ventral surface of L5. Thus, five out of the six ectopic bristles on Hsap\MADH4^{100T.Scer\UAS}/Scer\GAL4^Bx-MS1096 wings are derived from the transformation of sensilla.

Hsap\MADH4^{100T.Scer\UAS}/Scer\GAL4^Bx-MS1096 mutants show dosage-dependent effects, with multiple copies of Hsap\MADH4^{100T.Scer\UAS} exhibiting more severe phenotypes than those flies with a single copy. Single copy mutant wings exhibit a normal wing margin and around two sensilla-to-bristle transformations. Two-copy mutants exhibit a normal margin, sensilla-to-bristle transformation, and vein defects. Three-copy mutant wings exhibit a reduced size, a normal margin, sensilla-to-bristle transformation, and vein defects.

Expression of Hsap\MADH4^{100T.Scer\UAS} under the control of Scer\GAL4^en-e16E results in the transformation of patches of cells within the first denticle row into naked cuticle on one or more segments of most embryos.

Hsap\SMAD4^100T.UAS, Scer\GAL4^Bx-MS1096 is a suppressor of lethal | male phenotype of Scer\GAL4^Bx-MS1096, pan^ΔN.UAS