Depleting Mtor in the CySC lineage (c587ts>MtorRNAi) caused defects in GSC differentiation (S1B and S1F and S1H Fig) similar to those seen in cyst cells defective in the epidermal growth factor receptor (EGFR) signaling pathway [32–36; S1C and S1D Fig]. This evidence concerns the gene EGFR and cyst.