a, Schematic of Drosophila hindgut. Both larval and adult hindgut include the pylorus, ileum and rectum. During pupal stage metamorphosis, the pylorus and ileum from larval stage degenerate; the anterior part of pylorus (ring) regenerates to produce adult pylorus and ileum. b, Detecting eGFP positive cells from mdg4 transposition reporter in midgut, salivary gland and proventriculus at different stages. c, The box plot shows the number of eGFP positive cells from mdg4 transposition reporter in midgut, salivary gland and proventriculus.