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Imaging extracellular ATP with a genetically-encoded, ratiometric fluorescent sensor.

ABSTRACT: Extracellular adenosine triphosphate (ATP) is a key purinergic signal that mediates cell-to-cell communication both within and between organ systems. We address the need for a robust and minimally invasive approach to measuring extracellular ATP by re-engineering the ATeam ATP sensor to be expressed on the cell surface. Using this approach, we image real-time changes in extracellular ATP levels with a sensor that is fully genetically-encoded and does not require an exogenous substrate. In addition, the sensor is ratiometric to allow for reliable quantitation of extracellular ATP fluxes. Using live-cell microscopy, we characterize sensor performance when expressed on cultured Neuro2A cells, and we measure both stimulated release of ATP and its clearance by ectonucleotidases. Thus, this proof-of-principle demonstrates a first-generation sensor to report extracellular ATP dynamics that may be useful for studying purinergic signaling in living specimens.

SUBMITTER: Conley JM

PROVIDER: S-EPMC5679667 | biostudies-literature | 2017

REPOSITORIES: biostudies-literature

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Imaging extracellular ATP with a genetically-encoded, ratiometric fluorescent sensor.

Conley Jason M JM Radhakrishnan Saranya S Valentino Stephen A SA Tantama Mathew M

PloS one 20171109 11

Extracellular adenosine triphosphate (ATP) is a key purinergic signal that mediates cell-to-cell communication both within and between organ systems. We address the need for a robust and minimally invasive approach to measuring extracellular ATP by re-engineering the ATeam ATP sensor to be expressed on the cell surface. Using this approach, we image real-time changes in extracellular ATP levels with a sensor that is fully genetically-encoded and does not require an exogenous substrate. In additi ...[more]

PMID: 29121644

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