Fast functional mapping of ligand-gated ion channels

Ligand-gated ion channels are formed by three to five subunits that control the opening of the pore in a cooperative fashion. We developed a microfluidic chip-based technique for studying ion currents and fluorescence signals in either excised membrane patches or whole cells to measure activation an...

Full description

Saved in:
Bibliographic Details
Published in:Communications biology 2023-10, Vol.6 (1), p.1003-1003, Article 1003
Main Authors: Schmauder, Ralf, Eick, Thomas, Schulz, Eckhard, Sammler, Günther, Voigt, Elmar, Mayer, Günter, Ginter, Holger, Ditze, Günter, Benndorf, Klaus
Format: Article
Language:English
Subjects:
13/62
14/19
631/1647/1453/1970
631/57/2270/1140
631/57/2272/1590
631/57/2272/2275
631/57/2272/951
9/74
Biology
Biomedical and Life Sciences
Cell activation
Channel gating
Dose-response effects
Fluorometry
Ion channels
Ion channels (ligand-gated)
Ion currents
Ions
Kinetics
Life Sciences
Ligands
Microfluidics
Citations: Items that this one cites
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Ligand-gated ion channels are formed by three to five subunits that control the opening of the pore in a cooperative fashion. We developed a microfluidic chip-based technique for studying ion currents and fluorescence signals in either excised membrane patches or whole cells to measure activation and deactivation kinetics of the channels as well as ligand binding and unbinding when using confocal patch-clamp fluorometry. We show how this approach produces in a few seconds either unidirectional concentration-activation relationships at or near equilibrium and, moreover, respective time courses of activation and deactivation for a large number of freely designed steps of the ligand concentration. The short measuring period strongly minimizes the contribution of disturbing superimposing effects such as run-down phenomena and desensitization effects. To validate gating mechanisms, complex kinetic schemes are quantified without the requirement to have data at equilibrium. The new method has potential for functionally analyzing any ligand-gated ion channel and, beyond, also for other receptors. A multi-channel solution exchange system supplies up to 30 different external solutions to ligand-gated ion channels in a membrane patch in rapid succession, allowing to determine detailed dose-response relationships and dynamics in seconds.
ISSN:2399-3642
2399-3642
DOI:10.1038/s42003-023-05340-w