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dc.contributor.authorBlank, Paul S.
dc.contributor.authorVogel, Steven S.
dc.contributor.authorMalley, James D.
dc.contributor.authorZimmerberg, Joshua
dc.date.accessioned2012-10-26T16:26:41Z
dc.date.available2012-10-26T16:26:41Z
dc.date.issued2001-08-1en_US
dc.identifier.citationJ Gen Physiol. 2001 Aug 1; 118(2):145-156en_US
dc.identifier.issn1540-7748en_US
dc.identifier.pmid11479342en_US
dc.identifier.urihttp://hdl.handle.net/10675.2/562
dc.description.abstractAlthough the relationship between exocytosis and calcium is fundamental both to synaptic and nonneuronal secretory function, analysis is problematic because of the temporal and spatial properties of calcium, and the fact that vesicle transport, priming, retrieval, and recycling are coupled. By analyzing the kinetics of sea urchin egg secretory vesicle exocytosis in vitro , the final steps of exocytosis are resolved. These steps are modeled as a three-state system: activated, committed, and fused, where interstate transitions are given by the probabilities that an active fusion complex commits (a ) and that a committed fusion complex results in fusion, p . The number of committed complexes per vesicle docking site is Poisson distributed with mean n. Experimentally, p and n increase with increasing calcium, whereas a and the p/n ratio remain constant, reducing the kinetic description to only one calcium-dependent, controlling variable, . On average, the calcium dependence of the maximum rate (R max ) and the time to reach R max (T peak ) are described by the calcium dependence of n . Thus, the nonlinear relationship between the free calcium concentration and the rate of exocytosis can be explained solely by the calcium dependence of the distribution of fusion complexes at vesicle docking sites.
dc.rights© 2001 The Rockefeller University Pressen_US
dc.subjectOriginal Articleen_US
dc.titleA Kinetic Analysis of Calcium-Triggered Exocytosisen_US
dc.typeArticleen_US
dc.identifier.pmcidPMC2233829en_US
dc.contributor.corporatenameInstitute of Molecular Medicine and Genetics
refterms.dateFOA2019-04-09T21:08:55Z
html.description.abstractAlthough the relationship between exocytosis and calcium is fundamental both to synaptic and nonneuronal secretory function, analysis is problematic because of the temporal and spatial properties of calcium, and the fact that vesicle transport, priming, retrieval, and recycling are coupled. By analyzing the kinetics of sea urchin egg secretory vesicle exocytosis in vitro , the final steps of exocytosis are resolved. These steps are modeled as a three-state system: activated, committed, and fused, where interstate transitions are given by the probabilities that an active fusion complex commits (a ) and that a committed fusion complex results in fusion, p . The number of committed complexes per vesicle docking site is Poisson distributed with mean n. Experimentally, p and n increase with increasing calcium, whereas a and the p/n ratio remain constant, reducing the kinetic description to only one calcium-dependent, controlling variable, . On average, the calcium dependence of the maximum rate (R max ) and the time to reach R max (T peak ) are described by the calcium dependence of n . Thus, the nonlinear relationship between the free calcium concentration and the rate of exocytosis can be explained solely by the calcium dependence of the distribution of fusion complexes at vesicle docking sites.


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