TY - JOUR TI - Complexin induces a conformational change at the membrane-proximal C-terminal end of the SNARE complex AU - Choi, Ucheor B AU - Zhao, Minglei AU - Zhang, Yunxiang AU - Lai, Ying AU - Brunger, Axel T A2 - van Oijen, Antoine M VL - 5 PY - 2016 DA - 2016/06/02 SP - e16886 C1 - eLife 2016;5:e16886 DO - 10.7554/eLife.16886 UR - https://doi.org/10.7554/eLife.16886 AB - Complexin regulates spontaneous and activates Ca2+-triggered neurotransmitter release, yet the molecular mechanisms are still unclear. Here we performed single molecule fluorescence resonance energy transfer experiments and uncovered two conformations of complexin-1 bound to the ternary SNARE complex. In the cis conformation, complexin-1 induces a conformational change at the membrane-proximal C-terminal end of the ternary SNARE complex that specifically depends on the N-terminal, accessory, and central domains of complexin-1. The complexin-1 induced conformation of the ternary SNARE complex may be related to a conformation that is juxtaposing the synaptic vesicle and plasma membranes. In the trans conformation, complexin-1 can simultaneously interact with a ternary SNARE complex via the central domain and a binary SNARE complex consisting of syntaxin-1A and SNAP-25A via the accessory domain. The cis conformation may be involved in activation of synchronous neurotransmitter release, whereas both conformations may be involved in regulating spontaneous release. KW - synaptic vesicle fusion KW - neurotransmitter release KW - calcium triggering JF - eLife SN - 2050-084X PB - eLife Sciences Publications, Ltd ER -