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Insights into the molecular mechanisms underlying the inhibition of acid-sensing ion channel 3 gating by stomatin
Stomatin (STOM) is a monotopic integral membrane protein found in all classes of life that has been shown to regulate members of the acid-sensing ion channel (ASIC) family. However, the mechanism by which STOM alters ASIC function is not known. Using chimeric channels, we combined patch-clamp electr...
Autores principales: | , , |
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Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
Rockefeller University Press
2020
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Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7054857/ https://www.ncbi.nlm.nih.gov/pubmed/32012213 http://dx.doi.org/10.1085/jgp.201912471 |
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author | Klipp, Robert C. Cullinan, Megan M. Bankston, John R. |
author_facet | Klipp, Robert C. Cullinan, Megan M. Bankston, John R. |
author_sort | Klipp, Robert C. |
collection | PubMed |
description | Stomatin (STOM) is a monotopic integral membrane protein found in all classes of life that has been shown to regulate members of the acid-sensing ion channel (ASIC) family. However, the mechanism by which STOM alters ASIC function is not known. Using chimeric channels, we combined patch-clamp electrophysiology and FRET to search for regions of ASIC3 critical for binding to and regulation by STOM. With this approach, we found that regulation requires two distinct sites on ASIC3: the distal C-terminus and the first transmembrane domain (TM1). The C-terminal site is critical for formation of the STOM–ASIC3 complex, while TM1 is required only for the regulatory effect. We then looked at the mechanism of STOM-dependent regulation of ASIC3 and found that STOM does not alter surface expression of ASIC3 or shift the pH dependence of channel activation. However, a point mutation (Q269G) that prevents channel desensitization also prevents STOM regulation, suggesting that STOM may alter ASIC3 currents by stabilizing the desensitized state of the channel. Based on these findings, we propose a model whereby STOM is anchored to the channel via a site on the distal C-terminus and stabilizes the desensitized state of the channel via an interaction with TM1. |
format | Online Article Text |
id | pubmed-7054857 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2020 |
publisher | Rockefeller University Press |
record_format | MEDLINE/PubMed |
spelling | pubmed-70548572020-09-02 Insights into the molecular mechanisms underlying the inhibition of acid-sensing ion channel 3 gating by stomatin Klipp, Robert C. Cullinan, Megan M. Bankston, John R. J Gen Physiol Article Stomatin (STOM) is a monotopic integral membrane protein found in all classes of life that has been shown to regulate members of the acid-sensing ion channel (ASIC) family. However, the mechanism by which STOM alters ASIC function is not known. Using chimeric channels, we combined patch-clamp electrophysiology and FRET to search for regions of ASIC3 critical for binding to and regulation by STOM. With this approach, we found that regulation requires two distinct sites on ASIC3: the distal C-terminus and the first transmembrane domain (TM1). The C-terminal site is critical for formation of the STOM–ASIC3 complex, while TM1 is required only for the regulatory effect. We then looked at the mechanism of STOM-dependent regulation of ASIC3 and found that STOM does not alter surface expression of ASIC3 or shift the pH dependence of channel activation. However, a point mutation (Q269G) that prevents channel desensitization also prevents STOM regulation, suggesting that STOM may alter ASIC3 currents by stabilizing the desensitized state of the channel. Based on these findings, we propose a model whereby STOM is anchored to the channel via a site on the distal C-terminus and stabilizes the desensitized state of the channel via an interaction with TM1. Rockefeller University Press 2020-02-03 /pmc/articles/PMC7054857/ /pubmed/32012213 http://dx.doi.org/10.1085/jgp.201912471 Text en © 2020 Klipp et al. http://www.rupress.org/terms/https://creativecommons.org/licenses/by-nc-sa/4.0/This article is distributed under the terms of an Attribution–Noncommercial–Share Alike–No Mirror Sites license for the first six months after the publication date (see http://www.rupress.org/terms/). After six months it is available under a Creative Commons License (Attribution–Noncommercial–Share Alike 4.0 International license, as described at https://creativecommons.org/licenses/by-nc-sa/4.0/). |
spellingShingle | Article Klipp, Robert C. Cullinan, Megan M. Bankston, John R. Insights into the molecular mechanisms underlying the inhibition of acid-sensing ion channel 3 gating by stomatin |
title | Insights into the molecular mechanisms underlying the inhibition of acid-sensing ion channel 3 gating by stomatin |
title_full | Insights into the molecular mechanisms underlying the inhibition of acid-sensing ion channel 3 gating by stomatin |
title_fullStr | Insights into the molecular mechanisms underlying the inhibition of acid-sensing ion channel 3 gating by stomatin |
title_full_unstemmed | Insights into the molecular mechanisms underlying the inhibition of acid-sensing ion channel 3 gating by stomatin |
title_short | Insights into the molecular mechanisms underlying the inhibition of acid-sensing ion channel 3 gating by stomatin |
title_sort | insights into the molecular mechanisms underlying the inhibition of acid-sensing ion channel 3 gating by stomatin |
topic | Article |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7054857/ https://www.ncbi.nlm.nih.gov/pubmed/32012213 http://dx.doi.org/10.1085/jgp.201912471 |
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