RT Journal Article SR Electronic T1 P2X-GCaMPs as Versatile Tools for Imaging Extracellular ATP Signaling JF eneuro JO eNeuro FD Society for Neuroscience SP ENEURO.0185-20.2020 DO 10.1523/ENEURO.0185-20.2020 VO 8 IS 1 A1 Ollivier, Matthias A1 Beudez, Juline A1 Linck, Nathalie A1 Grutter, Thomas A1 Compan, Vincent A1 Rassendren, Francois YR 2021 UL http://www.eneuro.org/content/8/1/ENEURO.0185-20.2020.abstract AB ATP is an extracellular signaling molecule involved in numerous physiological and pathologic processes. However, in situ characterization of the spatiotemporal dynamic of extracellular ATP is still challenging because of the lack of sensor with appropriate specificity, sensitivity, and kinetics. Here, we report the development of biosensors based on the fusion of cation permeable ATP receptors (P2X) to genetically encoded calcium sensors [genetically encoded calcium indicator (GECI)]. By combining the features of P2X receptors with the high signal-to-noise ratio of GECIs, we generated ultrasensitive green and red fluorescent sniffers that detect nanomolar ATP concentrations in situ and also enable the tracking of P2X receptor activity. We provide the proof of concept that these sensors can dynamically track ATP release evoked by depolarization in mouse neurons or by extracellular hypotonicity. Targeting these P2X-based biosensors to diverse cell types should advance our knowledge of extracellular ATP dynamics in vivo.