Optimization of Ace2N based voltage indicators

Genetically encoded voltage indicators (GEVIs) are routinely used to image neuronal activity and they underlie many recent advances in cellular functional imaging. However, many sensors still have major limitations when used in vivo. Ace2N based voltage indicators, developed at different labs including Janelia, represents a class of GEVIs that’s sensitive (from spike detection to subthreshold membrane potential reporting), fast (submillisecond level for recently published ASAP2f variant) and other advantages depending on the fluorophore used. GENIE project engineers and optimizes a series of GEVIs including Ace2N based voltage indicators. With our high-throughput neuronal culture screening and patch clamp assay platform, we identified multiple single and combo mutations that dramatically improve the sensitivity to voltage change.