Interrogating Purinergic Signaling: From Extracellular ATP to Intracellular Second Messenger Dynamics

Abstract

Purinergic signals, such as extracellular adenosine triphosphate (ATP), mediate cell‐to‐cell communication during fundamental processes such as neural transmission, inflammation, and chemotaxis. Furthermore, the aberrant release of extracellular ATP can contribute to injury and disease, such as in epilepsy, cancer, and infections. Despite its importance in both physiological and pathophysiological conditions, it has remained a challenge to quantitatively measure the spatial and temporal dynamics of extracellular ATP because of the broad ranges of concentrations, distances, and timescales over which it acts. In order to address this challenge, we are developing genetically‐encoded biosensors that enable the visualization of the release and clearance of extracellular ATP. When extracellular ATP is released, it can activate P2 receptors, including P2X ligand‐gated ion channels and P2Y G‐protein coupled receptors, that lead to downstream intracellular signaling via second messengers such as calcium and cyclic adenosine monophosphate (cAMP). Thus, in order to interrogate purinergic signal transduction across the plasma membrane, we are also developing multiplex imaging methods that simultaneously monitor spectrally compatible sensors that correlate the dynamics of extracellular ATP release, purinergic receptor activation, and intracellular second messenger signaling. Using this integrative live‐cell imaging approach, we study both activity‐dependent and injury‐dependent purinergic signaling in neural systems.Support or Funding InformationWe gratefully acknowledge support from the Ralph W. and Grace M. Showalter Trust, the Purdue Research Foundation, and from National Institutes of Health grants R21 NS092010 and R21 EY026425.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.