气候变化领域集成服务门户(CCPortal): Synaptotagmin-1–, Munc18-1–, and Munc13-1–dependent liposome fusion with a few neuronal SNAREs

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DOI	10.1073/pnas.2019314118
	Synaptotagmin-1–, Munc18-1–, and Munc13-1–dependent liposome fusion with a few neuronal SNAREs
	Stepien K.P.; Rizo J.
发表日期	2021
ISSN	00278424
卷号	118 期号:4
英文摘要	Neurotransmitter release is governed by eight central proteins among other factors: the neuronal SNAREs syntaxin-1, synaptobrevin, and SNAP-25, which form a tight SNARE complex that brings the synaptic vesicle and plasma membranes together; NSF and SNAPs, which disassemble SNARE complexes; Munc18-1 and Munc13-1, which organize SNARE complex assembly; and the Ca2+ sensor synaptotagmin-1. Reconstitution experiments revealed that Munc18-1, Munc13-1, NSF, and α-SNAP can mediate Ca2+-dependent liposome fusion between synaptobrevin liposomes and syntaxin-1–SNAP-25 liposomes, but high fusion efficiency due to uncontrolled SNARE complex assembly did not allow investigation of the role of synaptotagmin-1 on fusion. Here, we show that decreasing the synaptobrevin-to-lipid ratio in the corresponding liposomes to very low levels leads to inefficient fusion and that synaptotagmin-1 strongly stimulates fusion under these conditions. Such stimulation depends on Ca2+ binding to the two C2 domains of synaptotagmin-1. We also show that anchoring SNAP-25 on the syntaxin-1 liposomes dramatically enhances fusion. Moreover, we uncover a synergy between synaptotagmin-1 and membrane anchoring of SNAP-25, which allows efficient Ca2+dependent fusion between liposomes bearing very low synaptobrevin densities and liposomes containing very low syntaxin-1 densities. Thus, liposome fusion in our assays is achieved with a few SNARE complexes in a manner that requires Munc18-1 and Munc13-1 and that depends on Ca2+ binding to synaptotagmin-1, all of which are fundamental features of neurotransmitter release in neurons. © 2021 National Academy of Sciences. All rights reserved.
英文关键词	Membrane fusion; Neurotransmitter release; Reconstitution; Synaptic vesicle fusion; Synaptotagmin-1
语种	英语
来源期刊	Proceedings of the National Academy of Sciences of the United States of America
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/180856
作者单位	Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, TX 75390, United States; Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, TX 75390, United States; Department of Pharmacology, University of Texas Southwestern Medical Center, Dallas, TX 75390, United States
推荐引用方式 GB/T 7714	Stepien K.P.,Rizo J.. Synaptotagmin-1–, Munc18-1–, and Munc13-1–dependent liposome fusion with a few neuronal SNAREs[J],2021,118(4).
APA	Stepien K.P.,&Rizo J..(2021).Synaptotagmin-1–, Munc18-1–, and Munc13-1–dependent liposome fusion with a few neuronal SNAREs.Proceedings of the National Academy of Sciences of the United States of America,118(4).
MLA	Stepien K.P.,et al."Synaptotagmin-1–, Munc18-1–, and Munc13-1–dependent liposome fusion with a few neuronal SNAREs".Proceedings of the National Academy of Sciences of the United States of America 118.4(2021).