Single-Channel Kinetic Analysis for Activation and Desensitization of Homomeric 5-HT3A Receptors
- Autores
- Corradi, Jeremias; Gumilar, Fernanda Andrea; Bouzat, Cecilia Beatriz
- Año de publicación
- 2009
- Idioma
- inglés
- Tipo de recurso
- documento de conferencia
- Estado
- versión publicada
- Descripción
- The 5-HT3A receptor is a member of the Cys-loop family of ligand-gated ion channels. Due to its low conductance, kinetic analysis of this receptor has been restricted to the macroscopic level. We introduced mutations in the 5- HT3A subunit to obtain a high-conductance form so that single-channel currents can be detected. At all 5-HT concentrations (>0.1 mM) channel activity appears as opening events in quick succession forming bursts, which, in turn, coalesce into clusters. By combining single-channel and macroscopic data we generated a detailed kinetic model that perfectly describes activation, deactivation and de- sensitization. The model shows that full activation arises from receptors with three molecules of agonist bound. It also reveals an earlier conformational change of the fully-liganded receptor (flipping) that occurs while the channel is still closed. From this pre-open state the receptor enters into an open-closed cycle involving three open states, which conforms the cluster whose duration parallels the time constant of desensitization. This suggests that at a synapse the lifetime of the elementary response of 5-HT3A receptors is determined mainly by desensitization. Since the desensitized state is a stable state, the in- ter-response latency is expected to be prolonged. The present kinetic model provides a foundation for studying molecular mechanisms of drug action. We show that mutations at valine 100 of M4 affect opening and closing rates within the open-closed cycle. This reveals that the outermost transmembrane domain is important for appropriate gating and shows a high conservation of M4 function among members of this superfamily.
Fil: Corradi, Jeremias. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Investigaciones Bioquímicas de Bahía Blanca. Universidad Nacional del Sur. Instituto de Investigaciones Bioquímicas de Bahía Blanca; Argentina
Fil: Gumilar, Fernanda Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Investigaciones Bioquímicas de Bahía Blanca. Universidad Nacional del Sur. Instituto de Investigaciones Bioquímicas de Bahía Blanca; Argentina
Fil: Bouzat, Cecilia Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Investigaciones Bioquímicas de Bahía Blanca. Universidad Nacional del Sur. Instituto de Investigaciones Bioquímicas de Bahía Blanca; Argentina
53th Annual Meeting Biophysical Society
Boston
Estados Unidos
Biophysical Society - Materia
-
ION CHANNEL
NICOTINIC ACETYLCHOLINE RECEPTOR - Nivel de accesibilidad
- acceso abierto
- Condiciones de uso
- https://creativecommons.org/licenses/by-nc-sa/2.5/ar/
- Repositorio
- Institución
- Consejo Nacional de Investigaciones Científicas y Técnicas
- OAI Identificador
- oai:ri.conicet.gov.ar:11336/252950
Ver los metadatos del registro completo
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CONICET Digital (CONICET) |
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Single-Channel Kinetic Analysis for Activation and Desensitization of Homomeric 5-HT3A ReceptorsCorradi, JeremiasGumilar, Fernanda AndreaBouzat, Cecilia BeatrizION CHANNELNICOTINIC ACETYLCHOLINE RECEPTORhttps://purl.org/becyt/ford/1.6https://purl.org/becyt/ford/1The 5-HT3A receptor is a member of the Cys-loop family of ligand-gated ion channels. Due to its low conductance, kinetic analysis of this receptor has been restricted to the macroscopic level. We introduced mutations in the 5- HT3A subunit to obtain a high-conductance form so that single-channel currents can be detected. At all 5-HT concentrations (>0.1 mM) channel activity appears as opening events in quick succession forming bursts, which, in turn, coalesce into clusters. By combining single-channel and macroscopic data we generated a detailed kinetic model that perfectly describes activation, deactivation and de- sensitization. The model shows that full activation arises from receptors with three molecules of agonist bound. It also reveals an earlier conformational change of the fully-liganded receptor (flipping) that occurs while the channel is still closed. From this pre-open state the receptor enters into an open-closed cycle involving three open states, which conforms the cluster whose duration parallels the time constant of desensitization. This suggests that at a synapse the lifetime of the elementary response of 5-HT3A receptors is determined mainly by desensitization. Since the desensitized state is a stable state, the in- ter-response latency is expected to be prolonged. The present kinetic model provides a foundation for studying molecular mechanisms of drug action. We show that mutations at valine 100 of M4 affect opening and closing rates within the open-closed cycle. This reveals that the outermost transmembrane domain is important for appropriate gating and shows a high conservation of M4 function among members of this superfamily.Fil: Corradi, Jeremias. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Investigaciones Bioquímicas de Bahía Blanca. Universidad Nacional del Sur. Instituto de Investigaciones Bioquímicas de Bahía Blanca; ArgentinaFil: Gumilar, Fernanda Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Investigaciones Bioquímicas de Bahía Blanca. Universidad Nacional del Sur. Instituto de Investigaciones Bioquímicas de Bahía Blanca; ArgentinaFil: Bouzat, Cecilia Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Investigaciones Bioquímicas de Bahía Blanca. Universidad Nacional del Sur. Instituto de Investigaciones Bioquímicas de Bahía Blanca; Argentina53th Annual Meeting Biophysical SocietyBostonEstados UnidosBiophysical SocietyCell Press2009info:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/conferenceObjectReuniónJournalhttp://purl.org/coar/resource_type/c_5794info:ar-repo/semantics/documentoDeConferenciaapplication/pdfapplication/pdfapplication/pdfhttp://hdl.handle.net/11336/252950Single-Channel Kinetic Analysis for Activation and Desensitization of Homomeric 5-HT3A Receptors; 53th Annual Meeting Biophysical Society; Boston; Estados Unidos; 2009; 486a-487a0006-34951542-0086CONICET DigitalCONICETenghttps://ri.conicet.gov.ar/handle/11336/66139info:eu-repo/semantics/altIdentifier/url/https://www.cell.com/biophysj/issue?pii=S0006-3495(09)X0003-2#closeFullCoverInternacionalinfo:eu-repo/semantics/openAccesshttps://creativecommons.org/licenses/by-nc-sa/2.5/ar/reponame:CONICET Digital (CONICET)instname:Consejo Nacional de Investigaciones Científicas y Técnicas2025-09-03T09:47:26Zoai:ri.conicet.gov.ar:11336/252950instacron:CONICETInstitucionalhttp://ri.conicet.gov.ar/Organismo científico-tecnológicoNo correspondehttp://ri.conicet.gov.ar/oai/requestdasensio@conicet.gov.ar; lcarlino@conicet.gov.arArgentinaNo correspondeNo correspondeNo correspondeopendoar:34982025-09-03 09:47:26.679CONICET Digital (CONICET) - Consejo Nacional de Investigaciones Científicas y Técnicasfalse |
dc.title.none.fl_str_mv |
Single-Channel Kinetic Analysis for Activation and Desensitization of Homomeric 5-HT3A Receptors |
title |
Single-Channel Kinetic Analysis for Activation and Desensitization of Homomeric 5-HT3A Receptors |
spellingShingle |
Single-Channel Kinetic Analysis for Activation and Desensitization of Homomeric 5-HT3A Receptors Corradi, Jeremias ION CHANNEL NICOTINIC ACETYLCHOLINE RECEPTOR |
title_short |
Single-Channel Kinetic Analysis for Activation and Desensitization of Homomeric 5-HT3A Receptors |
title_full |
Single-Channel Kinetic Analysis for Activation and Desensitization of Homomeric 5-HT3A Receptors |
title_fullStr |
Single-Channel Kinetic Analysis for Activation and Desensitization of Homomeric 5-HT3A Receptors |
title_full_unstemmed |
Single-Channel Kinetic Analysis for Activation and Desensitization of Homomeric 5-HT3A Receptors |
title_sort |
Single-Channel Kinetic Analysis for Activation and Desensitization of Homomeric 5-HT3A Receptors |
dc.creator.none.fl_str_mv |
Corradi, Jeremias Gumilar, Fernanda Andrea Bouzat, Cecilia Beatriz |
author |
Corradi, Jeremias |
author_facet |
Corradi, Jeremias Gumilar, Fernanda Andrea Bouzat, Cecilia Beatriz |
author_role |
author |
author2 |
Gumilar, Fernanda Andrea Bouzat, Cecilia Beatriz |
author2_role |
author author |
dc.subject.none.fl_str_mv |
ION CHANNEL NICOTINIC ACETYLCHOLINE RECEPTOR |
topic |
ION CHANNEL NICOTINIC ACETYLCHOLINE RECEPTOR |
purl_subject.fl_str_mv |
https://purl.org/becyt/ford/1.6 https://purl.org/becyt/ford/1 |
dc.description.none.fl_txt_mv |
The 5-HT3A receptor is a member of the Cys-loop family of ligand-gated ion channels. Due to its low conductance, kinetic analysis of this receptor has been restricted to the macroscopic level. We introduced mutations in the 5- HT3A subunit to obtain a high-conductance form so that single-channel currents can be detected. At all 5-HT concentrations (>0.1 mM) channel activity appears as opening events in quick succession forming bursts, which, in turn, coalesce into clusters. By combining single-channel and macroscopic data we generated a detailed kinetic model that perfectly describes activation, deactivation and de- sensitization. The model shows that full activation arises from receptors with three molecules of agonist bound. It also reveals an earlier conformational change of the fully-liganded receptor (flipping) that occurs while the channel is still closed. From this pre-open state the receptor enters into an open-closed cycle involving three open states, which conforms the cluster whose duration parallels the time constant of desensitization. This suggests that at a synapse the lifetime of the elementary response of 5-HT3A receptors is determined mainly by desensitization. Since the desensitized state is a stable state, the in- ter-response latency is expected to be prolonged. The present kinetic model provides a foundation for studying molecular mechanisms of drug action. We show that mutations at valine 100 of M4 affect opening and closing rates within the open-closed cycle. This reveals that the outermost transmembrane domain is important for appropriate gating and shows a high conservation of M4 function among members of this superfamily. Fil: Corradi, Jeremias. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Investigaciones Bioquímicas de Bahía Blanca. Universidad Nacional del Sur. Instituto de Investigaciones Bioquímicas de Bahía Blanca; Argentina Fil: Gumilar, Fernanda Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Investigaciones Bioquímicas de Bahía Blanca. Universidad Nacional del Sur. Instituto de Investigaciones Bioquímicas de Bahía Blanca; Argentina Fil: Bouzat, Cecilia Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Investigaciones Bioquímicas de Bahía Blanca. Universidad Nacional del Sur. Instituto de Investigaciones Bioquímicas de Bahía Blanca; Argentina 53th Annual Meeting Biophysical Society Boston Estados Unidos Biophysical Society |
description |
The 5-HT3A receptor is a member of the Cys-loop family of ligand-gated ion channels. Due to its low conductance, kinetic analysis of this receptor has been restricted to the macroscopic level. We introduced mutations in the 5- HT3A subunit to obtain a high-conductance form so that single-channel currents can be detected. At all 5-HT concentrations (>0.1 mM) channel activity appears as opening events in quick succession forming bursts, which, in turn, coalesce into clusters. By combining single-channel and macroscopic data we generated a detailed kinetic model that perfectly describes activation, deactivation and de- sensitization. The model shows that full activation arises from receptors with three molecules of agonist bound. It also reveals an earlier conformational change of the fully-liganded receptor (flipping) that occurs while the channel is still closed. From this pre-open state the receptor enters into an open-closed cycle involving three open states, which conforms the cluster whose duration parallels the time constant of desensitization. This suggests that at a synapse the lifetime of the elementary response of 5-HT3A receptors is determined mainly by desensitization. Since the desensitized state is a stable state, the in- ter-response latency is expected to be prolonged. The present kinetic model provides a foundation for studying molecular mechanisms of drug action. We show that mutations at valine 100 of M4 affect opening and closing rates within the open-closed cycle. This reveals that the outermost transmembrane domain is important for appropriate gating and shows a high conservation of M4 function among members of this superfamily. |
publishDate |
2009 |
dc.date.none.fl_str_mv |
2009 |
dc.type.none.fl_str_mv |
info:eu-repo/semantics/publishedVersion info:eu-repo/semantics/conferenceObject Reunión Journal http://purl.org/coar/resource_type/c_5794 info:ar-repo/semantics/documentoDeConferencia |
status_str |
publishedVersion |
format |
conferenceObject |
dc.identifier.none.fl_str_mv |
http://hdl.handle.net/11336/252950 Single-Channel Kinetic Analysis for Activation and Desensitization of Homomeric 5-HT3A Receptors; 53th Annual Meeting Biophysical Society; Boston; Estados Unidos; 2009; 486a-487a 0006-3495 1542-0086 CONICET Digital CONICET |
url |
http://hdl.handle.net/11336/252950 |
identifier_str_mv |
Single-Channel Kinetic Analysis for Activation and Desensitization of Homomeric 5-HT3A Receptors; 53th Annual Meeting Biophysical Society; Boston; Estados Unidos; 2009; 486a-487a 0006-3495 1542-0086 CONICET Digital CONICET |
dc.language.none.fl_str_mv |
eng |
language |
eng |
dc.relation.none.fl_str_mv |
https://ri.conicet.gov.ar/handle/11336/66139 info:eu-repo/semantics/altIdentifier/url/https://www.cell.com/biophysj/issue?pii=S0006-3495(09)X0003-2#closeFullCover |
dc.rights.none.fl_str_mv |
info:eu-repo/semantics/openAccess https://creativecommons.org/licenses/by-nc-sa/2.5/ar/ |
eu_rights_str_mv |
openAccess |
rights_invalid_str_mv |
https://creativecommons.org/licenses/by-nc-sa/2.5/ar/ |
dc.format.none.fl_str_mv |
application/pdf application/pdf application/pdf |
dc.coverage.none.fl_str_mv |
Internacional |
dc.publisher.none.fl_str_mv |
Cell Press |
publisher.none.fl_str_mv |
Cell Press |
dc.source.none.fl_str_mv |
reponame:CONICET Digital (CONICET) instname:Consejo Nacional de Investigaciones Científicas y Técnicas |
reponame_str |
CONICET Digital (CONICET) |
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CONICET Digital (CONICET) |
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Consejo Nacional de Investigaciones Científicas y Técnicas |
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CONICET Digital (CONICET) - Consejo Nacional de Investigaciones Científicas y Técnicas |
repository.mail.fl_str_mv |
dasensio@conicet.gov.ar; lcarlino@conicet.gov.ar |
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13.13397 |