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rdf:type |
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lifeskim:mentions |
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pubmed:issue |
1-3
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pubmed:dateCreated |
2002-4-17
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pubmed:abstractText |
The off rate from the first calcium-binding site of the C2A domain of synaptotagmin I, a putative calcium receptor in neurotransmitter release, has been determined by 15N-nuclear magnetic resonance relaxation dispersion measurements. The exchange rate was obtained by fitting the dependence of the transverse relaxation rates on the interval between 180 degrees pulses in relaxation-compensated CPMG experiments at 3.2 microM calcium concentration. The measured k(ex) is 2.0x10(3) x s(-1). The calcium on rate of 3.5+/-1x10(7) x s(-1), determined from the measured off rate and the dissociation constant (5.3x10(-5) M), is close to the diffusion limit. These results are consistent with the proposed role of synaptotagmin I as a calcium sensor in release, but suggest that additional factors may help to accelerate the diffusion of Ca2+ to the sensor.
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pubmed:grant |
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pubmed:language |
eng
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pubmed:journal |
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pubmed:citationSubset |
IM
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pubmed:chemical |
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pubmed:status |
MEDLINE
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pubmed:month |
Apr
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pubmed:issn |
0014-5793
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pubmed:author |
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pubmed:issnType |
Print
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pubmed:day |
10
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pubmed:volume |
516
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pubmed:owner |
NLM
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pubmed:authorsComplete |
Y
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pubmed:pagination |
93-6
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pubmed:dateRevised |
2007-11-14
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pubmed:meshHeading |
pubmed-meshheading:11959110-Binding Sites,
pubmed-meshheading:11959110-Calcium,
pubmed-meshheading:11959110-Calcium Signaling,
pubmed-meshheading:11959110-Calcium-Binding Proteins,
pubmed-meshheading:11959110-Kinetics,
pubmed-meshheading:11959110-Magnetic Resonance Spectroscopy,
pubmed-meshheading:11959110-Membrane Glycoproteins,
pubmed-meshheading:11959110-Models, Neurological,
pubmed-meshheading:11959110-Nerve Tissue Proteins,
pubmed-meshheading:11959110-Neurotransmitter Agents,
pubmed-meshheading:11959110-Protein Structure, Tertiary,
pubmed-meshheading:11959110-Synaptotagmin I,
pubmed-meshheading:11959110-Synaptotagmins
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pubmed:year |
2002
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pubmed:articleTitle |
NMR measurement of the off rate from the first calcium-binding site of the synaptotagmin I C2A domain.
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pubmed:affiliation |
Departament de Química Orgànica, Universitat de Barcelona, Martí i Franquès 1-11, 08028, Barcelona, Spain.
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pubmed:publicationType |
Journal Article,
In Vitro,
Research Support, U.S. Gov't, P.H.S.,
Research Support, Non-U.S. Gov't
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