Fig. 5. Regulation of msh by ara/caup and ap. (A) iro^DFM3 clone (absence of red; induced at 36-60 hours AEL). msh is autonomously upregulated (arrowhead). (B) Small, late-induced (60-84 hours AEL) iro^DFM3 clones (absence of red) near the hinge border (arrowhead) similarly derepress msh. (C) Clones overexpressing UAS-ara (induced at 36-60 hours AEL) autonomously repress msh in the hinge territory (arrowheads). (D) iro^DFM3 clones (absence of green) do not survive in the notum region of discs deficient for Msh (UAS-mshi was driven with ap-Gal4). Clones are found only in the dorsal hinge and in the wing pouch regions (arrows). The wild-type twin spots (bright green, arrowhead) indicate that mitotic recombination events took place in the notum territory. (E) Late third instar wing disc from a homozygous ap^UGO35 larva. msh expression (red) is absent in essentially all the dorsal compartment of the disc (arrowhead), but it is present in the ventral hinge (arrow). ara/caup expression is shown in green. n, notum territory; vh, ventral hinge. (F) Chip^e55 clones (absence of green; induced 24-48 hours AEL) failed to activate msh at the dorsal hinge (arrowhead) and dorsal wing pouch (blue arrowhead), but were without effect at the ventral hinge (arrow), consistent with the independence of msh expression in this territory from ap.