共 50 条
The carboxy-terminal domain of complexin I stimulates liposome fusion
被引:51
作者:
Malsam, Joerg
[1
]
Seiler, Florian
[1
]
Schollmeier, Yvette
[1
]
Rusu, Patricia
[1
]
Krause, Jean Michel
[1
]
Soellner, Thomas H.
[1
]
机构:
[1] Univ Heidelberg, Biochem Ctr, D-69120 Heidelberg, Germany
来源:
基金:
美国国家卫生研究院;
关键词:
exocytosis;
SNARE;
SYNAPTIC VESICLE EXOCYTOSIS;
NEUROTRANSMITTER RELEASE;
SNARE COMPLEX;
MEMBRANE-FUSION;
PHOSPHOLIPID-VESICLES;
DISTINCT DOMAINS;
SYNAPTOTAGMIN;
BINDING;
PROTEIN;
CA2+;
D O I:
10.1073/pnas.0812813106
中图分类号:
O [数理科学和化学];
P [天文学、地球科学];
Q [生物科学];
N [自然科学总论];
学科分类号:
07 ;
0710 ;
09 ;
摘要:
Regulated exocytosis requires tight coupling of the membrane fusion machinery to a triggering signal and a fast response time. Complexins are part of this regulation and, together with synaptotagmins, control calcium-dependent exocytosis. Stimulatory and inhibitory functions have been reported for complexins. To test if complexins directly affect membrane fusion, we analyzed the 4 known mammalian complexin isoforms in a reconstituted fusion assay. In contrast to complexin III (CpxIII) and CpxIV, CpxI and CpxII stimulated soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE)-pin assembly and membrane fusion. This stimulatory effect required a preincubation at low temperature and was specific for neuronal t-SNAREs. Stimulation of membrane fusion was lost when the carboxy-terminal domain of CpxI was deleted or serine 115, a putative phosphorylation site, was mutated. Transfer of the carboxy-terminal domain of CpxI to CpxIII resulted in a stimulatory CpxIII-I chimera. Thus, the carboxyterminal domains of CpxI and CpxII promote the fusion of high-curvature liposomes.
引用
收藏
页码:2001 / 2006
页数:6
相关论文
共 50 条