Oncogene cooperation in Drosophila
Upper row: Confocal micrographs of Drosophila eye imaginal disc epithelium (left and middle: xy sections, right: xz cross-section) carrying GFP-marked clonal tumors (green). Cell outlines are visualized with antibodies against Fasciclin III (blue) and DE-cadherin (red). Clonal activation of the Jun-N-terminal kinase (JNK) signaling pathway induces apoptosis and extrusion of dying cells from the epithelial surface. Surviving cells lose polarity and become motile.
Bottom row: Bright-field images of adult Drosophila eyes in which wild-type (left) or mutant clones were induced using the MARCM technique. JNK activation causes either tissue overgrowth (middle) or apoptosis (right) depending on the context of cooperating oncogenic mutations.