title: Dual-labeling method for electron microscopy to characterize synaptic connectivity using genetically encoded fluorescent reporters in Drosophila.
abstract: Light and electron microscopy (LM and EM) both offer important advantages for characterizing neuronal circuitry in intact brains: LM can reveal the general patterns neurons trace between brain areas, and EM can confirm synaptic connections between identified neurons within a small area. In a few species, genetic labeling with fluorescent proteins has been used with LM to visualize many kinds of neurons and to analyze their morphologies and projection patterns. However, combining these large-scale patterns with the fine detail available in EM analysis has been a technical challenge. To analyze the synaptic connectivity of neurons expressing fluorescent markers with EM, we developed a dual-labeling method for use with pre-embedded brains. In Drosophila expressing genetic labels and also injected with markers we visualized synaptic connections among two populations of neurons in the AL, one of which has been shown to mediate a specific function, odor evoked neural oscillation.
authors.affiliation: National Institutes of Health, National Institute of Child Health and Human Development, 35 Lincoln Drive, msc 3715, Bethesda, MD 20892, USA. nktanaka@cp.kyoto-u.ac.jp
authors.forename: Nobuaki K
authors.initials: NK
authors.lastname: Tanaka
authors.forename: Louis
authors.initials: L
authors.lastname: Dye
authors.forename: Mark
authors.initials: M
authors.lastname: Stopfer
mesh_terms: D000818:Animals; D030801:Animals, Genetically Modified; D001710:Biotin / Q000378:metabolism; D003911:Dextrans / Q000378:metabolism; D004330:Drosophila / Q000033:anatomy & histology* / Q000235:genetics; D029721:Drosophila Proteins / Q000235:genetics; D055032:Electron Microscope Tomography; D051717:Fushi Tarazu Transcription Factors; D049452:Green Fluorescent Proteins / Q000235:genetics*; D009833:Olfactory Pathways / Q000166:cytology*; D018034:Olfactory Receptor Neurons / Q000166:cytology* / Q000648:ultrastructure; D011993:Recombinant Fusion Proteins; D012235:Rhodamines / Q000378:metabolism; D013569:Synapses / Q000502:physiology* / Q000648:ultrastructure
chemical_list: D003911:Dextrans; D029721:Drosophila Proteins; D051717:Fushi Tarazu Transcription Factors; C080545:GAL4-ftzQ protein, Drosophila; D011993:Recombinant Fusion Proteins; D012235:Rhodamines; D049452:Green Fluorescent Proteins; C005358:tetramethylrhodamine; D001710:Biotin