Using FRET-Based Fluorescent Sensors to Monitor Cytosolic and Membrane-Proximal Extracellular ATP Levels
The assessment of local concentrations of extracellular ATP (eATP) at the site of receptor binding remains a challenge in the field of purinergic signaling. In many cases, biosensors exploiting the principle of Förster resonance energy transfer (FRET) have provided useful tools to visualize local concentrations of metabolites. A series of FRET-based biosensors based on the epsilon subunits of bacterial ATP synthases have been described for the visualisation of ATP. These sensors carry ATP-sensing units with different affinities for ATP, permitting imaging of ATP under the widely different concentration conditions found in subcellular locations such as the cytoplasm and the membrane-proximal extracellular space.
Key wordsFRET Microscopy FACS Live-cell imaging Biosensor Extracellular ATP
We thank G. Dubberke for technical assistance. This study was supported by the Deutsche Forschungsgemeinschaft (SFB1328 and grant Ha2569/5).
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