TY - JOUR
T1 - Munc18-1-regulated stage-wise SNARE assembly underlying synaptic exocytosis
AU - Ma, Lu
AU - Rebane, Aleksander A.
AU - Yang, Guangcan
AU - Xi, Zhiqun
AU - Kang, Yuhao
AU - Gao, Ying
AU - Zhang, Yongli
N1 - Funding Information:
We thank James Rothman, Frederick Hughson, Thomas Söllner, Jingshi Shen, Erdem Karatekin, Shyam Krishnakumar, Frederic Pincet, Xinming Zhang, and Junyi Jiao for discussion and reading the manuscript, Hong Qu, Bowei Su, and Haijia Yu for help in experiments, and Mengze He for preparing the videos. This work was supported by the NIH grant RO1GM093341 to Y. Z. Research reported in this publication was also supported in part by the Brain Research Foundation and by the Raymond and Beverly Sackler Institute for Biological, Physical and Engineering Sciences at Yale.
Publisher Copyright:
© Ma et al.
PY - 2015/12/23
Y1 - 2015/12/23
N2 - Synaptic-soluble N-ethylmaleimide-sensitive factor attachment receptor (SNARE) proteins couple their stage-wise folding/assembly to rapid exocytosis of neurotransmitters in a Munc18-1-dependent manner. The functions of the different assembly stages in exocytosis and the role of Munc18-1 in SNARE assembly are not well understood. Using optical tweezers, we observed four distinct stages of assembly in SNARE N-terminal, middle, C-terminal, and linker domains (or NTD, MD, CTD, and LD, respectively). We found that SNARE layer mutations differentially affect SNARE assembly. Comparison of their effects on SNARE assembly and on exocytosis reveals that NTD and CTD are responsible for vesicle docking and fusion, respectively, whereas MD regulates SNARE assembly and fusion. Munc18-1 initiates SNARE assembly and structures t-SNARE C-terminus independent of syntaxin N-terminal regulatory domain (NRD) and stabilizes the half-zippered SNARE complex dependent upon the NRD. Our observations demonstrate distinct functions of SNARE domains whose assembly is intimately chaperoned by Munc18-1.
AB - Synaptic-soluble N-ethylmaleimide-sensitive factor attachment receptor (SNARE) proteins couple their stage-wise folding/assembly to rapid exocytosis of neurotransmitters in a Munc18-1-dependent manner. The functions of the different assembly stages in exocytosis and the role of Munc18-1 in SNARE assembly are not well understood. Using optical tweezers, we observed four distinct stages of assembly in SNARE N-terminal, middle, C-terminal, and linker domains (or NTD, MD, CTD, and LD, respectively). We found that SNARE layer mutations differentially affect SNARE assembly. Comparison of their effects on SNARE assembly and on exocytosis reveals that NTD and CTD are responsible for vesicle docking and fusion, respectively, whereas MD regulates SNARE assembly and fusion. Munc18-1 initiates SNARE assembly and structures t-SNARE C-terminus independent of syntaxin N-terminal regulatory domain (NRD) and stabilizes the half-zippered SNARE complex dependent upon the NRD. Our observations demonstrate distinct functions of SNARE domains whose assembly is intimately chaperoned by Munc18-1.
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U2 - 10.7554/eLife.09580.001
DO - 10.7554/eLife.09580.001
M3 - Article
C2 - 26701912
AN - SCOPUS:84956956392
SN - 2050-084X
VL - 4
JO - eLife
JF - eLife
IS - DECEMBER2015
M1 - e09580
ER -