title: In Vivo Functional Brain Imaging Approach Based on Bioluminescent Calcium Indicator GFP-aequorin.
abstract: Functional in vivo imaging has become a powerful approach to study the function and physiology of brain cells and structures of interest. Recently a new method of Ca(2+)-imaging using the bioluminescent reporter GFP-aequorin (GA) has been developed. This new technique relies on the fusion of the GFP and aequorin genes, producing a molecule capable of binding calcium and - with the addition of its cofactor coelenterazine - emitting bright light that can be monitored through a photon collector. Transgenic lines carrying the GFP-aequorin gene have been generated for both mice and Drosophila. In Drosophila, the GFP-aequorin gene has been placed under the control of the GAL4/UAS binary expression system allowing for targeted expression and imaging within the brain. This method has subsequently been shown to be capable of detecting both inward Ca(2+)-transients and Ca(2+)-released from inner stores. Most importantly it allows for a greater duration in continuous recording, imaging at greater depths within the brain, and recording at high temporal resolutions (up to 8.3 msec). Here we present the basic method for using bioluminescent imaging to record and analyze Ca(2+)-activity within the mushroom bodies, a structure central to learning and memory in the fly brain.
authors.affiliation: Equipe: Imagerie Cérébrale Fonctionnelle et Comportements (ICFC), Institut des Neurosciences Paris-Saclay (Nero-PSI), UMR-9197, CNRS/Université Paris Sud; Interdisciplinary Program in Neuroscience, Graduate College, University of Iowa.
authors.forename: Arianna R
authors.initials: AR
authors.lastname: Lark
authors.affiliation: Interdisciplinary Program in Neuroscience, Graduate College, University of Iowa; Department of Anesthesia, Carver College of Medicine, University of Iowa.
authors.forename: Toshihiro
authors.initials: T
authors.lastname: Kitamoto
authors.affiliation: Equipe: Imagerie Cérébrale Fonctionnelle et Comportements (ICFC), Institut des Neurosciences Paris-Saclay (Nero-PSI), UMR-9197, CNRS/Université Paris Sud; jean-rene.martin@inaf.cnrs-gif.fr.
authors.forename: Jean-René
authors.initials: JR
authors.lastname: Martin
mesh_terms: D000331:Aequorin / Q000737:chemistry*; D000818:Animals; D030801:Animals, Genetically Modified; D001921:Brain / Q000166:cytology / Q000378:metabolism / Q000502:physiology*; D002118:Calcium / Q000032:analysis* / Q000378:metabolism; D020013:Calcium Signaling; D004331:Drosophila melanogaster; D005260:Female; D059907:Functional Neuroimaging / Q000379:methods*; D049452:Green Fluorescent Proteins / Q000737:chemistry*; D008027:Light; D008163:Luminescent Measurements / Q000379:methods*; D008297:Male; D051379:Mice
chemical_list: D049452:Green Fluorescent Proteins; D000331:Aequorin; D002118:Calcium