The synaptic vesicle protein synaptobrevin is an essential component of the vesicle release machinery along with its plasma membrane partners (syntaxin and SNAP-25), although in the absence of synaptobrevin release it is not completely eliminated. Deak et al. explored the structural requirements of synaptobrevin function by using engineered constructs to rescue release in hippocampal neurons cultured from synaptobrevin-deficient mice. Cellubrevin, which has divergent N- and C-terminal domains, but a nearly identical central SNARE motif with synaptobrevin, rescued transmission. An electrostatic interaction between arginine (R) and glutamine (Q) in the "zero layer" of each SNARE was not essential because an R-Q substitution in synaptobrevin rescued evoked and spontaneous release. However, spacing between the SNARE motif and C-terminal transmembrane domain was critical. Synaptobrevin with a 12-residue insertion between the SNARE motif and the transmembrane region provided only partial rescue, and synaptobrevin with a 24-residue insertion failed to rescue any function.

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News tips from the Journal of Neuroscience
Ferenc Deak, Ok-Ho Shin, Ege T. Kavalali, and Thomas C. S黡hof

Contact: Sara Harris

Society for Neuroscience