eprintid: 10049829
rev_number: 19
eprint_status: archive
userid: 608
dir: disk0/10/04/98/29
datestamp: 2018-06-11 15:24:40
lastmod: 2021-10-05 00:34:58
status_changed: 2018-06-11 15:24:40
type: article
metadata_visibility: show
creators_name: Rebane, AA
creators_name: Wang, B
creators_name: Ma, L
creators_name: Qu, H
creators_name: Coleman, J
creators_name: Krishnakumar, S
creators_name: Rothman, JE
creators_name: Zhang, Y
title: Two Disease-Causing SNAP-25B Mutations Selectively Impair SNARE C-terminal Assembly
ispublished: pub
divisions: UCL
divisions: B02
divisions: C07
divisions: D07
divisions: F81
keywords: Optical tweezers, SNARE assembly, membrane fusion, protein folding, neuropathy
note: This version is the author accepted manuscript. For information on re-use, please refer to the publisher’s terms and conditions.
abstract: Synaptic exocytosis relies on assembly of three soluble N-ethylmaleimide-sensitive factor attachment receptor (SNARE) proteins into a parallel four-helix bundle to drive membrane fusion. SNARE assembly occurs by stepwise zippering of the vesicle-associated SNARE (v-SNARE) onto a binary SNARE complex on the target plasma membrane (t-SNARE). Zippering begins with slow N-terminal association followed by rapid C-terminal zippering, which serves as a power stroke to drive membrane fusion. SNARE mutations have been associated with numerous diseases, especially neurological disorders. It remains unclear how these mutations affect SNARE zippering, partly due to difficulties to quantify the energetics and kinetics of SNARE assembly. Here, we used single-molecule optical tweezers to measure the assembly energy and kinetics of SNARE complexes containing single mutations I67T/N in neuronal SNARE synaptosomal-associated protein of 25 kDa (SNAP-25B), which disrupt neurotransmitter release and have been implicated in neurological disorders. We found that both mutations significantly reduced the energy of C-terminal zippering by ~ 10 kBT, but did not affect N-terminal assembly. In addition, we observed that both mutations lead to unfolding of the C-terminal region in the t-SNARE complex. Our findings suggest that both SNAP-25B mutations impair synaptic exocytosis by destabilizing SNARE assembly, rather than stabilizing SNARE assembly as previously proposed. Therefore, our measurements provide insights into the molecular mechanism of the disease caused by SNARE mutations.
date: 2018-02-16
date_type: published
publisher: ACADEMIC PRESS LTD- ELSEVIER SCIENCE LTD
official_url: https://doi.org/10.1016/j.jmb.2017.10.012
oa_status: green
full_text_type: other
language: eng
primo: open
primo_central: open_green
article_type_text: Article
verified: verified_manual
elements_id: 1504236
doi: 10.1016/j.jmb.2017.10.012
lyricists_name: Krishnakumar, Shyam
lyricists_name: Rothman, James
lyricists_id: SKRIS94
lyricists_id: JROTH20
actors_name: Krishnakumar, Shyam
actors_id: SKRIS94
actors_role: owner
full_text_status: public
publication: Journal of Molecular Biology
volume: 430
number: 4
pagerange: 479-490
pages: 12
issn: 1089-8638
citation:        Rebane, AA;    Wang, B;    Ma, L;    Qu, H;    Coleman, J;    Krishnakumar, S;    Rothman, JE;           Rebane, AA;  Wang, B;  Ma, L;  Qu, H;  Coleman, J;  Krishnakumar, S;  Rothman, JE;  Zhang, Y;   - view fewer <#>    (2018)    Two Disease-Causing SNAP-25B Mutations Selectively Impair SNARE C-terminal Assembly.                   Journal of Molecular Biology , 430  (4)   pp. 479-490.    10.1016/j.jmb.2017.10.012 <https://doi.org/10.1016/j.jmb.2017.10.012>.       Green open access   
 
document_url: https://discovery.ucl.ac.uk/id/eprint/10049829/1/Rebane%20et%20al_JMB%202018.pdf