The Yki targets Myc and Piwi are indispensable for reprogramming of the AM lineage. (A) org-1-RFP and phalloidin mark the VLM. (B) Induction of CRISPR in the AMs with org-1-GAL4 against Myc (org-1>>Cas9; t::gRNA-Myc4x) abolishes VLM differentiation and blocks AM dedifferentiation. (C and D) Expression of a GFP-tagged Myc (Myc::GFP) can be detected in the nuclei (arrowheads) of the AMDCs (arrows) shortly after AM fragmentation (C and C′), but is suppressed by forced expression of constitutive active Hpo with org-1-GAL4 (org-1>>hpo.ΔC) in pupae at stage P4 (D and D′). (E) Induction of RNAi in the AMs with org-1-GAL4 against piwi (org-1>>dsRNA-piwi) abolishes VLM differentiation. (F and G) Visualization of org-1-RFP and GFP tagged Piwi (Piwi::GFP) during AM lineage reprogramming. Whereas Piwi::GFP cannot be detected in the forming AMDCs during fragmentation of the AMs (F and F′), the VLM progenitor cells that arises from the AMDCs during reprogramming are clearly positive for cytoplasmic Piwi::GFP (G and G′). (H and H′) Forced expression of constitutive active Hpo with org-1-GAL4 (org-1>>hpo.ΔC) abolishes piwi::GFP expression in pupal stage P4. Scale bars in A, B, and E: 100 µm; C, D, and F–H: 10 µm. Actin is visualized with phalloidin; DNA is visualized with DAPI.
