ASAP1 and ASAP2: Fluorescent voltage sensor with fast kinetics for imaging high-frequency neuronal electrical activity

Researchers in Dr. Michael Lin's lab have developed a fluorescent voltage sensor for non-invasive optical monitoring of electrical events in living cells in vitro and in vivo. A longstanding goal of neuroscience has been the accurate optical reporting of electrical activity in genetically defined neuronal populations. Fluorescent voltage sensors offer a promising approach to this as they allow a set of neurons in a region to be genetically defined and simultaneously visualized without the need for chemical access. However, existing sensors have limitations such as slow kinetics and suboptimal fluorescence responses that hinder their ability to accurately sense the range of neuronal activity. To overcome these limitations, the inventors have developed a voltage sensor named Allosteric Sensor for Action Potentials 1 (ASAP1). ASAP1 has sufficient brightness, dynamic range and kinetics to detect neuronal activity ranging from subthreshold potentials to rapid trains of action potentials.

Stage of Research

The inventors have shown that ASAP1 is able to discriminate between subthreshold voltage changes, single action potentials, and closely spaced action potentials in neurons in culture and in brain slices.

Ongoing Research

Sensor development and optimization are ongoing.