Membrane Fusion Intermediates via Directional and Full Assembly of the SNARE Complex.

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Bibliographic Details
Title:	Membrane Fusion Intermediates via Directional and Full Assembly of the SNARE Complex.
Authors:	Hernandez, Javier M., Stein, Alexander, Behrmann, Elmar, Riedel, Dietmar, Cypionka, Anna, Farsi, Zohreh, Walla, Peter J., Raunser, Stefan, Jahn, Reinhard
Source:	Science (pre-March 2025). 6/22/2012, Vol. 336 Issue 6088, p1581-1584. 4p.
Subjects:	Cellular control mechanisms, Membrane fusion, SNARE proteins, Bilayer lipid membranes, Intermediates (Chemistry), N-ethylmaleimide sensitive factor, Biochemistry experiments
Abstract:	Cellular membrane fusion is thought to proceed through intermediates including docking of apposed lipid bilayers, merging of proximal leaflets to form a hemifusion diaphragm, and fusion pore opening. A membrane-bridging four-helix complex of soluble N-ethylmaleimide-sensitive factor attachment protein receptors (SNAREs) mediates fusion. However, how assembly of the SNARE complex generates docking and other fusion intermediates is unknown. Using a cell-free reaction, we identified intermediates visually and then arrested the SNARE fusion machinery when fusion was about to begin. Partial and directional assembly of SNAREs tightly docked bilayers, but efficient fusion and an extended form of hemifusion required assembly beyond the core complex to the membrane-connecting linkers. We propose that straining of lipids at the edges of an extended docking zone initiates fusion. [ABSTRACT FROM AUTHOR]
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Database:	Psychology and Behavioral Sciences Collection

Description
Abstract:	Cellular membrane fusion is thought to proceed through intermediates including docking of apposed lipid bilayers, merging of proximal leaflets to form a hemifusion diaphragm, and fusion pore opening. A membrane-bridging four-helix complex of soluble N-ethylmaleimide-sensitive factor attachment protein receptors (SNAREs) mediates fusion. However, how assembly of the SNARE complex generates docking and other fusion intermediates is unknown. Using a cell-free reaction, we identified intermediates visually and then arrested the SNARE fusion machinery when fusion was about to begin. Partial and directional assembly of SNAREs tightly docked bilayers, but efficient fusion and an extended form of hemifusion required assembly beyond the core complex to the membrane-connecting linkers. We propose that straining of lipids at the edges of an extended docking zone initiates fusion. [ABSTRACT FROM AUTHOR]
ISSN:	00368075
DOI:	10.1126/science.1221976