title: Monitoring brain activity with protein voltage and calcium sensors.
abstract: Understanding the roles of different cell types in the behaviors generated by neural circuits requires protein indicators that report neural activity with high spatio-temporal resolution. Genetically encoded fluorescent protein (FP) voltage sensors, which optically report the electrical activity in distinct cell populations, are, in principle, ideal candidates. Here we demonstrate that the FP voltage sensor ArcLight reports odor-evoked electrical activity in the in vivo mammalian olfactory bulb in single trials using both wide-field and 2-photon imaging. ArcLight resolved fast odorant-responses in individual glomeruli, and distributed odorant responses across a population of glomeruli. Comparisons between ArcLight and the protein calcium sensors GCaMP3 and GCaMP6f revealed that ArcLight had faster temporal kinetics that more clearly distinguished activity elicited by individual odorant inspirations. In contrast, the signals from both GCaMPs were a saturating integral of activity that returned relatively slowly to the baseline. ArcLight enables optical electrophysiology of mammalian neuronal population activity in vivo.
authors.affiliation: 1] Department of Cellular and Molecular Physiology, Yale University School of Medicine, 333 Cedar Street, New Haven CT 06520 [2] NeuroImaging Cluster, Marine Biological Laboratory, Woods Hole, MA 02543.
authors.forename: Douglas A
authors.initials: DA
authors.lastname: Storace
authors.affiliation: 1] Center for Functional Connectomics, Korea Institute of Science and Technology, Seoul 136-791, Republic of Korea [2] NeuroImaging Cluster, Marine Biological Laboratory, Woods Hole, MA 02543.
authors.forename: Oliver R
authors.initials: OR
authors.lastname: Braubach
authors.affiliation: Department of Cellular and Molecular Physiology, Yale University School of Medicine, 333 Cedar Street, New Haven CT 06520.
authors.forename: Lei
authors.initials: L
authors.lastname: Jin
authors.affiliation: 1] Department of Cellular and Molecular Physiology, Yale University School of Medicine, 333 Cedar Street, New Haven CT 06520 [2] Center for Functional Connectomics, Korea Institute of Science and Technology, Seoul 136-791, Republic of Korea [3] NeuroImaging Cluster, Marine Biological Laboratory, Woods Hole, MA 02543.
authors.forename: Lawrence B
authors.initials: LB
authors.lastname: Cohen
authors.affiliation: Center for Functional Connectomics, Korea Institute of Science and Technology, Seoul 136-791, Republic of Korea.
authors.forename: Uhna
authors.initials: U
authors.lastname: Sung
mesh_terms: D000200:Action Potentials; D000818:Animals; D015374:Biosensing Techniques; D001921:Brain / Q000502:physiology*; D002118:Calcium / Q000378:metabolism*; D000229:Dependovirus / Q000235:genetics; D005260:Female; D015870:Gene Expression; D005822:Genetic Vectors / Q000008:administration & dosage / Q000235:genetics; D051379:Mice; D008856:Microscopy, Fluorescence; D057054:Molecular Imaging; D009812:Odorants; D009830:Olfactory Bulb / Q000502:physiology; D019076:Transgenes
chemical_list: D002118:Calcium