Towards reconstitution of membrane fusion mediated by SNAREs and other synaptic proteins

Abstract

Proteoliposomes have been widely used for in vitro studies of membrane fusion mediated by synaptic proteins. Initially, such studies were made with large unsynchronized ensembles of vesicles. Such ensemble assays limited the insights into the SNARE-mediated fusion mechanism that could be obtained from them. Single particle microscopy experiments can alleviate many of these limitations but they pose significant technical challenges. Here we summarize various approaches that have enabled studies of fusion mediated by SNAREs and other synaptic proteins at a single-particle level. Currently available methods are described and their advantages and limitations are discussed.

• Membrane fusion
• neuronal SNAREs
• neurotransmitter release
• single molecule FRET
• single particle microscopy
• synaptotagmin
• synaptic vesicle

Acknowledgments

We thank Steven Chu for a longstanding collaboration that led to the development of some of the assays discussed in this review, and Mark Bowen, Keith Weninger, and Jose Rizo for critical reading.

Declaration of interest

This work was supported by the Howard Hughes Medical Institute and the U.S. National Institutes of Health (grant R37-MH63105 to ATB).