Frontiers in Cellular Neuroscience (Nov 2013)

A genetically-encoded chloride and pH sensor for dissociating ion dynamics in the nervous system

  • Joseph Valentino Raimondo,
  • Joseph Valentino Raimondo,
  • Bradley eJoyce,
  • Louise eKay,
  • Theresa eSchlagheck,
  • Sarah Elizabeth Newey,
  • Shankar eSrinivas,
  • Colin Jon Akerman

DOI
https://doi.org/10.3389/fncel.2013.00202
Journal volume & issue
Vol. 7

Abstract

Read online

Within the nervous system, intracellular Cl- and pH regulate fundamental processes including cell proliferation, metabolism, synaptic transmission and network excitability. Cl- and pH are often co-regulated, and network activity results in the movement of both Cl- and H+. Tools to accurately measure these ions are crucial for understanding their role under physiological and pathological conditions. Although genetically-encoded Cl- and pH sensors have been described previously, these either lack ion specificity or are unsuitable for neuronal use. Here we present ClopHensorN - a new genetically-encoded ratiometric Cl- and pH sensor that is optimized for the nervous system. We demonstrate the ability of ClopHensorN to dissociate and simultaneously quantify Cl- and H+ concentrations under a variety of conditions. In addition, we establish the sensor’s utility by characterizing activity-dependent ion dynamics in hippocampal neurons.

Keywords