@article{0e4872d31cc24cc185ee37e07adca8f4,
title = "UNC-18 and tomosyn antagonistically control synaptic vesicle priming downstream of UNC-13 in Caenorhabditis elegans",
abstract = "Munc18-1/UNC-18 is believed to prime SNARE-mediated membrane fusion, yet the underlying mechanisms remain enigmatic. Here, we examine how potential gain-of-function mutations of Munc18-1/UNC-18 affect locomotory behavior and synaptic transmission, and how Munc18-1-mediated priming is related to Munc13-1/UNC-13 and Tomosyn/TOM-1, positive and negative SNARE regulators, respectively. We show that a Munc18-1(P335A)/UNC-18(P334A) mutation leads to significantly increased locomotory activity and acetylcholine release in Caenorhabditis elegans, as well as enhanced synaptic neurotransmission in cultured mammalian neurons. Importantly, similar to tom-1 null mutants, unc-18(P334A) mutants partially bypass the requirement of UNC-13. Moreover, unc-18(P334A) and tom-1 null mutations confer a strong synergy in suppressing the phenotypes of unc-13 mutants. Through biochemical experiments, we demonstrate that Munc18-1(P335A) exhibits enhanced activity in SNARE complex formation as well as in binding to the preformed SNARE complex, and partially bypasses the Munc13-1 requirement in liposome fusion assays. Our results indicate that Munc18-1/UNC-18 primes vesicle fusion downstream of Munc13-1/ UNC-13 by templating SNARE complex assembly and acts antagonistically with Tomosyn/TOM-1.",
keywords = "C.elegans, Exocytosis, Membrane fusion, Munc18, SNARE, Synapse",
author = "Seungmee Park and Bin, {Na Ryum} and Bin Yu and Raymond Wong and Ewa Sitarska and Kyoko Sugita and Ke Ma and Junjie Xu and Tien, {Chi Wei} and Arash Algouneh and Ekaterina Turlova and Siyan Wang and Pranay Siriya and Waleed Shahid and Lorraine Kalia and Feng, {Zhong Ping} and Monnier, {Philippe P.} and Sun, {Hong Shuo} and Mei Zhen and Shangbang Gao and Jose Rizo-Rey and Shuzo Sugita",
note = "Funding Information: This work was supported by Natural Sciences and Engineering Research Council of Canada Grants RGPIN-2015-06438 (S.S.), 2014-06471 (Z.P.F.), and RGPIN-2016-04574 (H.S.S.); Heart and Stroke Foundation of Ontario Grant 0171(S.S.),CanadianInstituteofHealthResearchGrantsMOP-93665and130573(S.S.)andMOP-93619and123250 (M.Z.);NIHResearchProjectAwardR35NS097333(J.R.),whichcontinuesresearchperformedpreviouslyunderNIH Funding Information: GrantsNS037200andNS049044(J.R.);andNationalNaturalScienceFoundationofChinaGrant31671052andJunior Thousand Talents Program of China and Wuhan Morning Light Plan of Youth Science and Technology Grant 2017050304010295 (S.G.). We thank Dr. Hitoshi Kitayama (Kyoto University, Kyoto, Japan) for providing us with punc-18andpMunc18-1plasmids.TheCB81strainwithagenotypeofunc-18(e81)andRM299withunc-18(md299)were provided by the Caenorhabditis Genetics Center at the University of Minnesota, which is funded by NIH Publisher Copyright: {\textcopyright} 2017 the authors.",
year = "2017",
month = sep,
day = "6",
doi = "10.1523/JNEUROSCI.0338-17.2017",
language = "English (US)",
volume = "37",
pages = "8797--8815",
journal = "Journal of Neuroscience",
issn = "0270-6474",
publisher = "Society for Neuroscience",
number = "36",
}