The Fab-8 boundary element (an AluI-MscI 659bp fragment 3R:12745503-12744844 ) has been inserted into the NsiI site of Abd-BFab7-2.tHa.
Abd-BFab7-2.Fab8 mutant flies (in a Abd-Bblt background) show a transformation of A6 towards A5. The sixth sternite exhibits an A5 shape and has bristles. This transformation is less severe when the construct is inserted in the wild type orientation relative to the Abd-B gene. In the wild type orientation the trichomes cover most of the transformed segment, whereas in the opposite orientation the trichomes primarily cover the ventral-anterior region of the transformed segment.