Insertion 125bp upstream of the predicted rpr transcription start site.
32% of anterior dMP2 neurons survive in late stage rprNP0520/Df(3L)H99 embryos (in contrast to wild-type embryos, where these neurons are lost by the late embryonic stage). Some anterior MP1 neurons survive in late stage rprNP0520/Df(3L)H99 embryos (in contrast to wild-type embryos, where these neurons are lost by the late embryonic stage).