SNARE complex formation is triggered by Ca2+ and drives membrane fusion

被引：358

作者：

Chen, YA ^{[1
]}

Scales, SJ ^{[1
]}

Patel, SM ^{[1
]}

Doung, YC ^{[1
]}

Scheller, RH ^{[1
]}

机构：

[1] Stanford Univ, Sch Med, Howard Hughes Med Inst, Dept Cellular & Mol Physiol, Stanford, CA 94305 USA

来源：

CELL | 1999年 / 97卷 / 02期

关键词：

D O I：

10.1016/S0092-8674(00)80727-8

中图分类号：

Q5 [生物化学]; Q7 [分子生物学];

学科分类号：

071010 ; 081704 ;

摘要：

Neurotransmitter exocytosis, a process mediated by a core complex of syntaxin, SNAP-25, and VAMP (SNAREs), is inhibited by SNARE-cleaving neurotoxins. Botulinum neurotoxin E inhibition of norepinephrine release in permeabilized PC12 cells can be rescued by adding a 65 aa C-terminal fragment of SNAP-25 (S25-C). Mutations along the hydrophobic face of the S25-C helix result in SNARE complexes with different thermostabilities, and these mutants rescue exocytosis to different extents. Rescue depends on the continued presence of both S25-C and Ca2+ and correlates with complex formation. The data suggest that Ca2+ triggers S25-C binding to a low-affinity site, initiating trans-complex formation. Pairing of SNARE proteins on apposing membranes leads to bilayer fusion and results in a high-affinity cis-SNARE complex.

引用

页码：165 / 174

页数：10

共 42 条

[1] N-ethylmaleimide-sensitive factor acts at a profusion ATP-dependent step in Ca2+-activated exocytosis [J].