library_construction_protocol: PolyA+ selected libraries were produced from individual whole Drosophila brains (4 heads per group). Specifically, total RNA was prepared using the RNAqueous-Micro kit (Ambion) followed by polyA+ mRNA isolation with the Dynabeads mRNA DIRECT Micro kit (Ambion) according to the manufacturer's protocols. Barcoded libraries (Ion XpressRNA) were made using the Ion Total RNA-Seq Kit v2, PCR-amplified, and quantified with Agilent Bioanalyzer (Agilent).