Publication Date:
2007-05-05
Description:
Synaptic vesicles loaded with neurotransmitters are exocytosed in a soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE)-dependent manner after presynaptic depolarization induces calcium ion (Ca2+) influx. The Ca2+ sensor required for fast fusion is synaptotagmin-1. The activation energy of bilayer-bilayer fusion is very high (approximately 40 k(B)T). We found that, in response to Ca2+ binding, synaptotagmin-1 could promote SNARE-mediated fusion by lowering this activation barrier by inducing high positive curvature in target membranes on C2-domain membrane insertion. Thus, synaptotagmin-1 triggers the fusion of docked vesicles by local Ca2+-dependent buckling of the plasma membrane together with the zippering of SNAREs. This mechanism may be widely used in membrane fusion.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Martens, Sascha -- Kozlov, Michael M -- McMahon, Harvey T -- MC_U105178795/Medical Research Council/United Kingdom -- New York, N.Y. -- Science. 2007 May 25;316(5828):1205-8. Epub 2007 May 3.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Medical Research Council-Laboratory of Molecular Biology, Hills Road, CB2 0QH Cambridge, UK.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/17478680" target="_blank"〉PubMed〈/a〉
Keywords:
Animals
;
Calcium/*physiology
;
Cell Membrane/*physiology/ultrastructure
;
Exocytosis/physiology
;
Humans
;
Liposomes
;
Membrane Fusion
;
Models, Biological
;
Rats
;
SNARE Proteins/*physiology
;
Synaptic Vesicles/*physiology/ultrastructure
;
Synaptotagmin I/*physiology
Print ISSN:
0036-8075
Electronic ISSN:
1095-9203
Topics:
Biology
,
Chemistry and Pharmacology
,
Computer Science
,
Medicine
,
Natural Sciences in General
,
Physics
