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Studying KcsA Channel Clustering Using Single Channel Voltage-Clamp Fluorescence Imaging*

Oligomerization and complex formation play a key role for many membrane proteins and has been described to influence ion channel function in both neurons and the heart. In this study, we observed clustering of single KcsA channels in planar lipid bilayer using single molecule fluorescence, while sim...

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Detalles Bibliográficos
Autores principales: McGuire, Hugo, Blunck, Rikard
Formato: Online Artículo Texto
Lenguaje:English
Publicado: Frontiers Media S.A. 2022
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9204084/
https://www.ncbi.nlm.nih.gov/pubmed/35721536
http://dx.doi.org/10.3389/fphys.2022.863375
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author McGuire, Hugo
Blunck, Rikard
author_facet McGuire, Hugo
Blunck, Rikard
author_sort McGuire, Hugo
collection PubMed
description Oligomerization and complex formation play a key role for many membrane proteins and has been described to influence ion channel function in both neurons and the heart. In this study, we observed clustering of single KcsA channels in planar lipid bilayer using single molecule fluorescence, while simultaneously measuring single channel currents. Clustering coincided with cooperative opening of KcsA. We demonstrate that clustering was not caused by direct protein-protein interactions or hydrophobic mismatch with the lipid environment, as suggested earlier, but was mediated via microdomains induced by the channel in the lipid matrix. We found that single channel activity of KcsA requires conically-shaped lipids in the lamellar liquid-crystalline (L(α)) phase, and the need for a negative spontaneous curvature seem to lead to the deformations in the membrane that cause the clustering. The method introduced here will be applicable to follow oligomerization of a wide range of membrane proteins.
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spelling pubmed-92040842022-06-18 Studying KcsA Channel Clustering Using Single Channel Voltage-Clamp Fluorescence Imaging* McGuire, Hugo Blunck, Rikard Front Physiol Physiology Oligomerization and complex formation play a key role for many membrane proteins and has been described to influence ion channel function in both neurons and the heart. In this study, we observed clustering of single KcsA channels in planar lipid bilayer using single molecule fluorescence, while simultaneously measuring single channel currents. Clustering coincided with cooperative opening of KcsA. We demonstrate that clustering was not caused by direct protein-protein interactions or hydrophobic mismatch with the lipid environment, as suggested earlier, but was mediated via microdomains induced by the channel in the lipid matrix. We found that single channel activity of KcsA requires conically-shaped lipids in the lamellar liquid-crystalline (L(α)) phase, and the need for a negative spontaneous curvature seem to lead to the deformations in the membrane that cause the clustering. The method introduced here will be applicable to follow oligomerization of a wide range of membrane proteins. Frontiers Media S.A. 2022-06-03 /pmc/articles/PMC9204084/ /pubmed/35721536 http://dx.doi.org/10.3389/fphys.2022.863375 Text en Copyright © 2022 McGuire and Blunck. https://creativecommons.org/licenses/by/4.0/This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
spellingShingle Physiology
McGuire, Hugo
Blunck, Rikard
Studying KcsA Channel Clustering Using Single Channel Voltage-Clamp Fluorescence Imaging*
title Studying KcsA Channel Clustering Using Single Channel Voltage-Clamp Fluorescence Imaging*
title_full Studying KcsA Channel Clustering Using Single Channel Voltage-Clamp Fluorescence Imaging*
title_fullStr Studying KcsA Channel Clustering Using Single Channel Voltage-Clamp Fluorescence Imaging*
title_full_unstemmed Studying KcsA Channel Clustering Using Single Channel Voltage-Clamp Fluorescence Imaging*
title_short Studying KcsA Channel Clustering Using Single Channel Voltage-Clamp Fluorescence Imaging*
title_sort studying kcsa channel clustering using single channel voltage-clamp fluorescence imaging*
topic Physiology
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9204084/
https://www.ncbi.nlm.nih.gov/pubmed/35721536
http://dx.doi.org/10.3389/fphys.2022.863375
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