Fig. 1.

Oncogenic Notch synergizes with lgl-IR to induce tissue overgrowth. Fluorescent micrographs of eye imaginal discs and larval brains are shown. ey-GAL4/+ (control) eye imaginal disc shows expression of GFP (a) and MMP1 (a′). ey-GAL4 driven UAS-N^act results in enlarged disc size (b) and shows slight enhancement in MMP1 expression (b′). UAS-lgl-IR eye disc driven by ey-GAL4 (c) induces MMP1 expression (c′). UAS-N^act coexpressed with UAS-lgl-IR results in massively overgrown eye discs (d) and significant enhancement in MMP1 expression throughout the tissue (d′) compared to that of only lgl-IR (c′) or only Notch^act (b′) overexpressed eye discs. Images a″–d″ are merges of those in a–a′, b–b′, c–c′ and d–d′ with DAPI, respectively. Expression of GFP and MMP1 in brains of ey-GAL4 driven UAS-N^act (f, f′) and UAS-lgl-IR (g, g′) remain similar as of wild-type brain (e, e′). h UAS-N^act and UAS-lgl-IR coexpressed brain shows massive expression of GFP in the optic lobes and in ventral nerve cord (arrowhead marks the expression of GFP in VNC). h′ The optic lobes and VNC of N^act/lgl-IR brain shows extensive expression of MMP1 (arrow marks the expression of MMP1 in VNC). Images e″–h″ are merges of those in e–e′, f–f′, g–g′ and h–h′ with DAPI, respectively. All eye discs are oriented with dorsal to the left and anterior to the top position. Dorsal view of the brains is shown. Scale bars, 50 µm (a–d, a′–d′, a″–d″) and 100 µm (e–h, e′–h′, e″–h″)