title: Archaerhodopsin Selectively and Reversibly Silences Synaptic Transmission through Altered pH.
abstract: Tools that allow acute and selective silencing of synaptic transmission in vivo would be invaluable for understanding the synaptic basis of specific behaviors. Here, we show that presynaptic expression of the proton pump archaerhodopsin enables robust, selective, and reversible optogenetic synaptic silencing with rapid onset and offset. Two-photon fluorescence imaging revealed that this effect is accompanied by a transient increase in pH restricted to archaerhodopsin-expressing boutons. Crucially, clamping intracellular pH abolished synaptic silencing without affecting the archaerhodopsin-mediated hyperpolarizing current, indicating that changes in pH mediate the synaptic silencing effect. To verify the utility of this technique, we used trial-limited, archaerhodopsin-mediated silencing to uncover a requirement for CA3-CA1 synapses whose afferents originate from the left CA3, but not those from the right CA3, for performance on a long-term memory task. These results highlight optogenetic, pH-mediated silencing of synaptic transmission as a spatiotemporally selective approach to dissecting synaptic function in behaving animals.
authors.affiliation: Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge CB2 3EG, UK.
authors.forename: Mohamady
authors.initials: M
authors.lastname: El-Gaby
authors.affiliation: Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge CB2 3EG, UK.
authors.forename: Yu
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge CB2 3EG, UK.
authors.forename: Konstantin
authors.initials: K
authors.lastname: Wolf
authors.affiliation: Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge CB2 3EG, UK.
authors.forename: Christof J
authors.initials: CJ
authors.lastname: Schwiening
authors.affiliation: Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge CB2 3EG, UK. Electronic address: op210@cam.ac.uk.
authors.forename: Ole
authors.initials: O
authors.lastname: Paulsen
authors.affiliation: Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge CB2 3EG, UK. Electronic address: olivia.shipton@gmail.com.
authors.forename: Olivia A
authors.initials: OA
authors.lastname: Shipton
mesh_terms: D000256:Adenoviridae / Q000235:genetics / Q000378:metabolism; D000818:Animals; D019843:Archaeal Proteins / Q000235:genetics* / Q000378:metabolism; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D056547:CA1 Region, Hippocampal / Q000502:physiology*; D056654:CA3 Region, Hippocampal / Q000502:physiology*; D015870:Gene Expression; D005822:Genetic Vectors / Q000737:chemistry / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D007276:Injections, Intraventricular; D008164:Luminescent Proteins / Q000235:genetics / Q000378:metabolism; D008297:Male; D057567:Memory, Long-Term / Q000502:physiology*; D051379:Mice; D008810:Mice, Inbred C57BL; D009473:Neuronal Plasticity / Q000502:physiology; D061848:Optical Imaging; D062308:Optogenetics / Q000379:methods; D017729:Presynaptic Terminals / Q000502:physiology*; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D013238:Stereotaxic Techniques; D009435:Synaptic Transmission / Q000502:physiology*; D017494:Proton Pumps
chemical_list: D019843:Archaeal Proteins; D001426:Bacterial Proteins; D008164:Luminescent Proteins; D011993:Recombinant Fusion Proteins; C055476:archaerhodopsin protein, Archaea; D017494:Proton Pumps; C054562:yellow fluorescent protein, Bacteria
keywords: archaerhodopsin; asymmetry; behavior; hippocampus; long-term memory; optogenetics; pH; reversible; synapses; synaptic silencing