let-7-C expression inversely correlates with Br-Z3 and Chinmo expression in the CNS during the larval-to-pupal transition. (A-E). Dissected CNS from (A) pre-wandering larva (pWL), (B) wandering larva (WL), (C) white prepupa (P0), (D)12 hr-old pupa (12hr), and (E) 24 hr-old pupa (P24) stained for let-7-Cp12.5kb::lacZ transcriptional reporter (green in A-E, white in A’-E’), Br-Z3 (red in A-E, white in A’’-E’’) and Chinmo (blue in A-E, white in A’’’-E’’’). Insets: single confocal sections of the VNC at each timepoint. (F-J) Dissected CNS from (F) pre-wandering larva (pWL), (G) wandering larva (WL), (H) white prepupa (P0), (I)12 hr-old pupa (12hr), and (J) 24 hr-old pupa (P24) stained for let-7-CΔ3miR::optGal4 > mcherry (red), Br-Z3 (green) and Chinmo (blue). Scale bars: A-J, 150µm.