Expression of JNKDN, but not aPKCCAAXDN, in scrib1 + RasACT tumours restores differentiation. Larval eye/antennal imaginal discs, with brain lobes (bl) attached (G-J), containing eyFLP-induced MARCM clones (green) at day 5 (A-F), day 7 (G, H) and day 9 (I, J). Grey scale is Elav and Red is phalloidin to mark F-actin. A white bar indicates the location of the MF. (A, B) UAS-dRas1V12; FRT82B scrib1. Expression of RasACT in scrib mutant clones results in tumour overgrowth basally. In apical sections, some differentiation is still observed in mutant tissue, although more basal sections show tumour cells overgrowing without differentiation. (C, D) UAS-dRas1V12; FRT82B scrib1 UAS-bskDN. Co-expression of BskDN with RasACT in scrib mutant clones restores differentiation to the tumour cells in both apical and basal sections. (E-I) UAS-dRas1V12; FRT82B scrib1 UAS-DaPKCCAAXDN. Co-expression of aPKCCAAXDN with RasACT in scrib mutant clones fails to restore differentiation to the tumour cells (E, F) that continue to massively overgrow and invade between the brain lobes (G, H), resulting in neoplasias at day 9 (I) that are only marginally smaller than day 9 scrib1 + RasACT tumours (J).