A genetically encoded ratiometric indicator for chloride: capturing chloride transients in cultured hippocampal neurons.


Journal Article

We constructed a novel optical indicator for chloride ions by fusing the chloride-sensitive yellow fluorescent protein with the chloride-insensitive cyan fluorescent protein. The ratio of FRET-dependent emission of these fluorophores varied in proportion to the concentration of Cl and was used to measure intracellular chloride concentration ([Cl-]i) in cultured hippocampal neurons. [Cl-]i decreased during neuronal development, consistent with the shift from excitation to inhibition during maturation of GABAergic synapses. Focal activation of GABAA receptors caused large changes in [Cl-]i that could underlie use-dependent depression of GABA-dependent synaptic transmission. GABA-induced changes in somatic [Cl-]i spread into dendrites, suggesting that [Cl-]i can signal the location of synaptic activity. This genetically encoded indicator will permit new approaches ranging from high-throughput drug screening to direct recordings of synaptic Cl- signals in vivo.

Full Text

Cited Authors

  • Kuner, T; Augustine, GJ

Published Date

  • September 2000

Published In

Volume / Issue

  • 27 / 3

Start / End Page

  • 447 - 459

PubMed ID

  • 11055428

Pubmed Central ID

  • 11055428

Electronic International Standard Serial Number (EISSN)

  • 1097-4199

International Standard Serial Number (ISSN)

  • 0896-6273

Digital Object Identifier (DOI)

  • 10.1016/s0896-6273(00)00056-8


  • eng