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Authordc.contributor.authorMoczydlowski, Edward 
Authordc.contributor.authorLatorre, Ramón 
Admission datedc.date.accessioned2019-01-29T14:20:46Z
Available datedc.date.available2019-01-29T14:20:46Z
Publication datedc.date.issued1983
Cita de ítemdc.identifier.citationJournal of General Physiology, Volume 82 October 1983 511-542
Identifierdc.identifier.issn15407748
Identifierdc.identifier.issn00221295
Identifierdc.identifier.other10.1085/jgp.82.4.511
Identifierdc.identifier.urihttp://repositorio.uchile.cl/handle/2250/160503
Abstractdc.description.abstractThe gating kinetics of a Ca2+-activated K+ channel from adult rat muscle plasma membrane are studied in artificial planar bilayers. Analysis of single-channel fluctuations distinguishes two Ca2+- and voltage-dependent processes: (a) short-lived channel closure (<1 ms) events appearing in a bursting pattern; (b) opening and closing events ranging from one to several hundred milliseconds in duration. The latter process is studied independently of the first and is denoted as the primary gating mode. At constant voltage, the mean open time of the primary gating mode is a linear function of the [Ca2+, whereas the mean closed time is a linear function of the reciprocal [Ca2+]. In the limits of zero and infinite [Ca2+], the mean open and the mean closed times are, respectively, independent of voltage. These results are predicted by a kinetic scheme consisting of the following reaction steps: (a) binding of Ca2+ to a closed state; (b) channel opening; (c) binding of a second Ca2+ ion. In this scheme, the two Ca2+ binding reactions are voltage dependent, whereas the open-closed transition is voltage independent. The kinetic constant derived for this scheme gives an accurate theoretical fit to the observed equilibrium open-state probability . The results provide evidence for a novel regulatory mechanism for the activity of an ion channel : modulation by voltage of the binding of an agonist molecule, in this case, Ca2+ ion .
Lenguagedc.language.isoen
Type of licensedc.rightsAttribution-NonCommercial-NoDerivs 3.0 Chile
Link to Licensedc.rights.urihttp://creativecommons.org/licenses/by-nc-nd/3.0/cl/
Sourcedc.sourceJournal of General Physiology
Keywordsdc.subjectPhysiology
Títulodc.titleGating kinetics of Ca++-activated K+ channels from rat muscle incorporated into planar lipid bilayers: Evidence for two voltage-dependent Ca2+ binding reactions
Document typedc.typeArtículo de revista
Catalogueruchile.catalogadorlaj
Indexationuchile.indexArtículo de publicación SCOPUS
uchile.cosechauchile.cosechaSI


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Attribution-NonCommercial-NoDerivs 3.0 Chile
Except where otherwise noted, this item's license is described as Attribution-NonCommercial-NoDerivs 3.0 Chile