Publication Date:
2001-11-03
Description:
In the exocytosis of neurotransmitter, fusion pore opening represents the first instant of fluid contact between the vesicle lumen and extracellular space. The existence of the fusion pore has been established by electrical measurements, but its molecular composition is unknown. The possibility that synaptotagmin regulates fusion pores was investigated with amperometry to monitor exocytosis of single dense-core vesicles. Overexpression of synaptotagmin I prolonged the time from fusion pore opening to dilation, whereas synaptotagmin IV shortened this time. Both synaptotagmin isoforms reduced norepinephrine flux through open fusion pores. Thus, synaptotagmin interacts with fusion pores, possibly by associating with a core complex of membrane proteins and/or lipid.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Wang, C T -- Grishanin, R -- Earles, C A -- Chang, P Y -- Martin, T F -- Chapman, E R -- Jackson, M B -- New York, N.Y. -- Science. 2001 Nov 2;294(5544):1111-5.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Physiology, University of Wisconsin Medical School, University of Wisconsin, Madison, WI 53706, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/11691996" target="_blank"〉PubMed〈/a〉
Keywords:
Animals
;
Calcium/metabolism
;
Calcium Channels, P-Type/metabolism
;
Calcium Channels, Q-Type/metabolism
;
*Calcium-Binding Proteins
;
Cell Membrane Structures/*metabolism
;
Chromogranins/metabolism
;
Electrophysiology
;
*Exocytosis
;
Kinetics
;
*Membrane Fusion
;
Membrane Glycoproteins/*metabolism
;
Membrane Potentials
;
Nerve Tissue Proteins/*metabolism
;
Neurotransmitter Agents/*metabolism
;
Norepinephrine/metabolism
;
PC12 Cells
;
Protein Isoforms
;
Rats
;
Recombinant Fusion Proteins/metabolism
;
Secretory Vesicles/*metabolism
;
Synaptic Transmission
;
Synaptic Vesicles/metabolism
;
Synaptotagmin I
;
Synaptotagmins
Print ISSN:
0036-8075
Electronic ISSN:
1095-9203
Topics:
Biology
,
Chemistry and Pharmacology
,
Computer Science
,
Medicine
,
Natural Sciences in General
,
Physics
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