Figure 4

JAK and Notch signaling can not be coordinately activated in scrib / dlg mutant FCs at the posterior. Wild type (A, D, F and I) and mosaic egg chambers with scrib² (B, E and G) or dlg^m52 (C, H and J) clones marked by the absence of nuclear GFP (green in B, E, G and J) or β-gal (green in C and H), stained for nuclei (DAPI, blue) and STAT92E (red in A-C), Hnt (red in D-E), Cut (red in F-H) or β-gal (red in I-J). (A-C) In the wild type egg chamber at stage 9, STAT92E accumulates to high levels in nuclei at the posterior pole, with gradual reduction toward the center of the chamber (A, A'). STAT92E nuclear accumulation was present only in the outer layer of the multilayered scrib² (B-B") and dlg^m52 (C-C") clones. Note that the wild type polar cells (arrows in B, B', C and C') are in close proximity to the single layer of outer cells of multilayered clones. (D, E) Hnt is expressed in all wild type FCs after stage 6 (D). In scrib² multilayered clones, Hnt expression can be detected in the inner cells, rather in outer layer (E-E"). (F-H) In the wild type, expression of Cut is present in FCs until stage 6 (F). In a stage 9 egg chamber with scrib² (G-G") or dlg^m52 (H-H") clone, Cut expression is evident in the outer layer of the multilayered clone. Note that Cut remains in a low level in the inner cells. (I, J) The Notch signaling reporter m7-lacZ can be activated in all FCs from stage 6-8 in the wild type (I). The m7-lacZ activity is localized to the inner cells of multilayered clones in dlg^m52 egg chamber at stage 7 (J-J").