Expression of sob^Scer\UAS.cGa under the control of Scer\GAL4^ptc-559.1 results in deep creases in the leg cuticle that extend along the anterior-posterior axis of the leg and resemble ectopic joint-like structures. Expression of sob^Scer\UAS.cGa under the control of Scer\GAL4^Dll-md23 results in fused tarsal segments and two sets of sex combs on the leg. Clones in the leg expressing sob^Scer\UAS.cGa under the control of Scer\GAL4^Act5C.PI never induce leg tissue outgrowths. Cells in the pretarsal epithelium at the tip of the late third instar leg disc that are expressing sob^Scer\UAS.cGa under the control of Scer\GAL4^ptc-559.1 appear to invaginate, resulting in an indentation in the epithelium. This is in contrast to control discs, where the pretarsal epithelium forms a flat sheet at the same stage.