Octopamine signaling regulates the intracellular pattern of the presynaptic active zone scaffold within Drosophila mushroom body neurons
Fig 1
Cell-type-specific dissection of the endogenous active zone scaffold.
(A) Schematic of split-GFP tagging system. GFP11 was inserted prior to the stop codon of brp, while GFP1–10 was expressed in specific cell types using the GAL4-UAS system. GFP11 and GFP1–10 reconstitute to emit fluorescence. (B) Visualization of Brp::rGFP in a cell-type-specific manner. Maximum intensity projections are shown. Immunostaining using antibody nc82 which labels all Brp in the brain, as a comparison to Brp::rGFP. Diagrams in each panel show the innervation pattern of neurons in the MB. GAL4 lines used: γ KCs (MB009B-GAL4), α/β KCs (MB008B-GAL4), α′/β′ KCs (MB370B-GAL4), PPL-1 (TH-GAL4), PAM (R58E02-GAL4), DPM (VT64246-GAL4), APL (GH146-GAL4). Scale bar, 20 μm. (C) Long-term live imaging of Brp::rGFP (green) in a growing motor neuron (magenta, CD4::tdTomato) from 48 to 96 h APF. OK371-GAL4 was used to express GFP1–10 and CD4::tdTomato. White boxes indicate zoomed-in areas shown in the lower panels. Scale bars: upper panels, 10 μm; lower panels, 5 μm. (D) Ex vivo live-imaging of Brp::rGFP in 3rd instar larval KCs. GFP1–10 was expressed using R13F02-GAL4. The left panel shows the MB calyx region. White boxes indicate zoomed-in areas shown on the right panels. Boxes 1 and 2 demonstrate Brp::rGFP fission and fusion event. White arrows indicate Brp::rGFP clusters undergoing fission or fusion. Scale bars: left panel, 10 μm; right panels, 200 nm.