Journal
EMBO JOURNAL
Volume 25, Issue 5, Pages 955-966Publisher
WILEY
DOI: 10.1038/sj.emboj.7601003
Keywords
capacitance measurements; chromaffin cells; exocytosis; SNAP-25; SNARE proteins
Categories
Ask authors/readers for more resources
During exocytosis a four-helical coiled coil is formed between the three SNARE proteins syntaxin, synaptobrevin and SNAP-25, bridging vesicle and plasma membrane. We have investigated the assembly pathway of this complex by interfering with the stability of the hydrophobic interaction layers holding the complex together. Mutations in the C-terminal end affected fusion triggering in vivo and led to two-step unfolding of the SNARE complex in vitro, indicating that the C-terminal end can assemble/disassemble independently. Free energy perturbation calculations showed that assembly of the C-terminal end could liberate substantial amounts of energy that may drive fusion. In contrast, similar N-terminal mutations were without effects on exocytosis, and mutations in the middle of the complex selectively interfered with upstream maturation steps (vesicle priming), but not with fusion triggering. We conclude that the SNARE complex forms in the N- to C-terminal direction, and that a partly assembled intermediate corresponds to the primed vesicle state.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available