Enhancer trap expression is observedin developing mechanosensory bristles. In microchaetae, the SOP, it'sprogeny and all four final progeny are stained. In macrochaetae, all fourprogeny are also stained. At later stages of macrochaetae development, theneuron and glial cell show the highest level of staining. In embryos,staining is observed in very early embryos indicating maternal expression.When the nervous system forms, expression is restricted to neurons in boththe CNS and the PNS. Larval staining is also predominantly in neurons. Inthe adult head, the highest levels of expression are in the laminalportion of the optic lobe, in the brain, and in the antenna.