Mutation of a single residue promotes gating of vertebrate and invertebrate two-pore domain potassium channels

• Published in: Nature communications Vol. 10; no. 1; p. 787
• Main Authors: Ben Soussia, Ismail, El Mouridi, Sonia, Kang, Dawon, Leclercq-Blondel, Alice, Khoubza, Lamyaa, Tardy, Philippe, Zariohi, Nora, Gendrel, Marie, Lesage, Florian, Kim, Eun-Jin, Bichet, Delphine, Andrini, Olga, Boulin, Thomas
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 15.02.2019; Nature Publishing Group; Nature Portfolio
• Subjects: 42/41; 42/70; 631/1647/1453; 631/1647/1511; 631/1647/334; 631/378/2586; 64; 64/11; 9/97; Acids; Amino acids; Animals; Asparagine; Caenorhabditis elegans; Caenorhabditis elegans Proteins - genetics; Caenorhabditis elegans Proteins - metabolism; Channel gating; Channel opening; CRISPR; CRISPR-Cas Systems - genetics; CRISPR-Cas Systems - physiology; Drosophila; Evolution, Molecular; Genetic modification; Genome editing; Human health and pathology; Humanities and Social Sciences; Humans; Invertebrates; Ion channels; Life Sciences; Membrane Potentials - genetics; Membrane Potentials - physiology; multidisciplinary; Mutation; Mutation - genetics; Neurobiology; Neurons and Cognition; Potassium; Potassium channels; Potassium Channels, Tandem Pore Domain - genetics; Potassium Channels, Tandem Pore Domain - metabolism; Recording; Science; Science (multidisciplinary); Selectivity; Tissues and Organs; Vertebrates
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/s41467-019-08710-3

Mutations that modulate the activity of ion channels are essential tools to understand the biophysical determinants that control their gating. Here, we reveal the conserved role played by a single amino acid position (TM2.6) located in the second transmembrane domain of two-pore domain potassium (K2P) channels. Mutations of TM2.6 to aspartate or asparagine increase channel activity for all vertebrate K2P channels. Using two-electrode voltage-clamp and single-channel recording techniques, we find that mutation of TM2.6 promotes channel gating via the selectivity filter gate and increases single channel open probability. Furthermore, channel gating can be progressively tuned by using different amino acid substitutions. Finally, we show that the role of TM2.6 was conserved during evolution by rationally designing gain-of-function mutations in four Caenorhabditis elegans K2P channels using CRISPR/ Cas9 gene editing. This study thus describes a simple and powerful strategy to systematically manipulate the activity of an entire family of potassium channels. Mutations that modulate the activity of ion channels are essential tools to understand the biophysical determinants that control their gating. Here authors reveal the role played by a single residue in the second transmembrane domain of vertebrate and invertebrate two-pore domain potassium channels.