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High-fidelity optical reporting of neuronal electrical activity with an ultrafast fluorescent voltage sensor.

ABSTRACT: Accurate optical reporting of electrical activity in genetically defined neuronal populations is a long-standing goal in neuroscience. We developed Accelerated Sensor of Action Potentials 1 (ASAP1), a voltage sensor design in which a circularly permuted green fluorescent protein is inserted in an extracellular loop of a voltage-sensing domain, rendering fluorescence responsive to membrane potential. ASAP1 demonstrated on and off kinetics of ? 2 ms, reliably detected single action potentials and subthreshold potential changes, and tracked trains of action potential waveforms up to 200 Hz in single trials. With a favorable combination of brightness, dynamic range and speed, ASAP1 enables continuous monitoring of membrane potential in neurons at kilohertz frame rates using standard epifluorescence microscopy.

SUBMITTER: St-Pierre F

PROVIDER: S-EPMC4494739 | biostudies-literature | 2014 Jun

REPOSITORIES: biostudies-literature

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High-fidelity optical reporting of neuronal electrical activity with an ultrafast fluorescent voltage sensor.

St-Pierre François F Marshall Jesse D JD Yang Ying Y Gong Yiyang Y Schnitzer Mark J MJ Lin Michael Z MZ

Nature neuroscience 20140422 6

Accurate optical reporting of electrical activity in genetically defined neuronal populations is a long-standing goal in neuroscience. We developed Accelerated Sensor of Action Potentials 1 (ASAP1), a voltage sensor design in which a circularly permuted green fluorescent protein is inserted in an extracellular loop of a voltage-sensing domain, rendering fluorescence responsive to membrane potential. ASAP1 demonstrated on and off kinetics of ∼ 2 ms, reliably detected single action potentials and ...[more]

PMID: 24755780

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