Absolute Membrane Potential Recording with ASAP-Type Genetically Encoded Voltage Indicators Using Fluorescence Lifetime Imaging.

ABSTRACT: The electrical membrane voltage (V_m) characterizes the functional state of biological cells, thus requiring precise, noninvasive V_m-sensing techniques. While voltage-dependent fluorescence intensity changes from genetically encoded voltage indicators (GEVIs) indicate V_m changes, variability in sensor expression confounds the determination of absolute V_m. Fluorescence lifetime imaging microscopy (FLIM) promises a solution to this problem, as fluorescence lifetime is expected to be unaffected by sensor expression and excitation intensity. By examining ASAP1, ASAP3, JEDI-1P, rEstus, and rEstus-NI (G138N:T141I) with one-photon-excited FLIM measurements, we demonstrate that all sensors display a voltage-dependent lifetime.

SUBMITTER: Nair AG 

PROVIDER: S-EPMC12715753 | biostudies-literature | 2025 Dec

REPOSITORIES: biostudies-literature