Home LiteratureArticle Details
PMID: 22000513 Published · ppublish English Journal Article Research Support, N.I.H., Extramural Research Support, Non-U.S. Gov't

The crystal structure of a Munc13 C-terminal module exhibits a remarkable similarity to vesicle tethering factors.

Structure (London, England : 1993) ·Vol. 19 ·No. 10 ·2011-10-12 ·Pages 1443-55

Li W, Ma C, Guan R, Xu Y, Tomchick DR, Rizo J

Abstract

Unc13/Munc13s play a crucial function in neurotransmitter release through their MUN domain, which mediates the transition from the Syntaxin-1/Munc18-1 complex to the SNARE complex. The MUN domain was suggested to be related to tethering factors, but no MUN-domain structure is available to experimentally validate this notion and address key unresolved questions about the interactions and minimal structural unit required for Unc13/Munc13 function. Here we identify an autonomously folded module within the MUN domain (MUN-CD) and show that its crystal structure is remarkably similar to several tethering factors. We also show that the activity in promoting the Syntaxin-1/Munc18-1 to SNARE complex transition is strongly impaired in MUN-CD. These results show that MUN domains and tethering factors indeed belong to the same family and may have a common role in membrane trafficking. We propose a model whereby the MUN-CD module is central for Munc13 function but full activity requires adjacent sequences.

MeSH Terms
Animals Humans Intracellular Membranes/chemistry Magnetic Resonance Spectroscopy Membrane Fusion Models, Molecular Multiprotein Complexes/chemistry Nerve Tissue Proteins/chemistry Protein Binding Protein Structure, Secondary Rats Recombinant Proteins/chemistry Static Electricity Structure-Activity Relationship Synaptic Vesicles/chemistry Synaptosomal-Associated Protein 25/chemistry Syntaxin 1/chemistry Vesicle-Associated Membrane Protein 2/chemistry X-Ray Diffraction
Chemicals
Multiprotein Complexes Nerve Tissue Proteins Recombinant Proteins SNAP25 protein, human Stx1a protein, rat Synaptosomal-Associated Protein 25 Syntaxin 1 Unc13a protein, rat Vamp2 protein, rat Vesicle-Associated Membrane Protein 2
Authors & Affiliations
6 authors, click to expand affiliations / ORCID
Li Wei
Department of Biochemistry, University of Texas Southwestern Medical Center, 6000 Harry Hines Boulevard, Dallas, TX 75390, USA.
Ma Cong
Guan Rong
Xu Yibin
Tomchick Diana R
Rizo Josep
References (73)
73 references, click to expand
  1. Binding of the Munc13-1 MUN domain to membrane-anchored SNARE complexes.
    Biochemistry. 2008 Feb 12;47(6):1474-81 PMID: 18201107
  2. UNC-13 and UNC-10/rim localize synaptic vesicles to specific membrane domains.
    J Neurosci. 2006 Aug 2;26(31):8040-7 PMID: 16885217
  3. Protein folding and association: insights from the interfacial and thermodynamic properties of hydrocarbons.
    Proteins. 1991;11(4):281-96 PMID: 1758883
  4. Identification of the minimal protein domain required for priming activity of Munc13-1.
    Curr Biol. 2005 Dec 20;15(24):2243-8 PMID: 16271475
  5. The structures of exocyst subunit Exo70p and the Exo84p C-terminal domains reveal a common motif.
    Nat Struct Mol Biol. 2005 Dec;12(12):1094-100 PMID: 16249794
  6. Membrane fusion.
    Nat Struct Mol Biol. 2008 Jul;15(7):658-64 PMID: 18618939
  7. The Buccaneer software for automated model building. 1. Tracing protein chains.
    Acta Crystallogr D Biol Crystallogr. 2006 Sep;62(Pt 9):1002-11 PMID: 16929101
  8. Protein structure comparison by alignment of distance matrices.
    J Mol Biol. 1993 Sep 5;233(1):123-38 PMID: 8377180
  9. Munc13-4 is essential for cytolytic granules fusion and is mutated in a form of familial hemophagocytic lymphohistiocytosis (FHL3).
    Cell. 2003 Nov 14;115(4):461-73 PMID: 14622600
  10. Line narrowing in methyl-TROSY using zero-quantum 1H-13C NMR spectroscopy.
    J Am Chem Soc. 2004 Apr 21;126(15):4921-5 PMID: 15080697
  11. SNAREs--engines for membrane fusion.
    Nat Rev Mol Cell Biol. 2006 Sep;7(9):631-43 PMID: 16912714
  12. DaliLite workbench for protein structure comparison.
    Bioinformatics. 2000 Jun;16(6):566-7 PMID: 10980157
  13. A Munc13/RIM/Rab3 tripartite complex: from priming to plasticity?
    EMBO J. 2005 Aug 17;24(16):2839-50 PMID: 16052212
  14. Definition of Munc13-homology-domains and characterization of a novel ubiquitously expressed Munc13 isoform.
    Biochem J. 2000 Jul 1;349(Pt 1):247-53 PMID: 10861235
  15. Synaptic vesicle fusion.
    Nat Struct Mol Biol. 2008 Jul;15(7):665-74 PMID: 18618940
  16. Combining constraints for electron-density modification.
    Methods Enzymol. 1997;277:53-64 PMID: 18488305
  17. Dimerization of the exocyst protein Sec6p and its interaction with the t-SNARE Sec9p.
    Biochemistry. 2005 Apr 26;44(16):6302-11 PMID: 15835919
  18. How Tlg2p/syntaxin 16 'snares' Vps45.
    EMBO J. 2002 Jul 15;21(14):3620-31 PMID: 12110575
  19. Direct interaction of the rat unc-13 homologue Munc13-1 with the N terminus of syntaxin.
    J Biol Chem. 1997 Jan 24;272(4):2520-6 PMID: 8999968
  20. CAPS drives trans-SNARE complex formation and membrane fusion through syntaxin interactions.
    Proc Natl Acad Sci U S A. 2009 Oct 13;106(41):17308-13 PMID: 19805029
  21. A conformational switch in syntaxin during exocytosis: role of munc18.
    EMBO J. 1999 Aug 16;18(16):4372-82 PMID: 10449403
  22. MolProbity: all-atom contacts and structure validation for proteins and nucleic acids.
    Nucleic Acids Res. 2007 Jul;35(Web Server issue):W375-83 PMID: 17452350
  23. Substructure solution with SHELXD.
    Acta Crystallogr D Biol Crystallogr. 2002 Oct;58(Pt 10 Pt 2):1772-9 PMID: 12351820
  24. Selective activation of cognate SNAREpins by Sec1/Munc18 proteins.
    Cell. 2007 Jan 12;128(1):183-95 PMID: 17218264
  25. Three-dimensional structure of the complexin/SNARE complex.
    Neuron. 2002 Jan 31;33(3):397-409 PMID: 11832227
  26. Accessory proteins stabilize the acceptor complex for synaptobrevin, the 1:1 syntaxin/SNAP-25 complex.
    Structure. 2008 Feb;16(2):308-20 PMID: 18275821
  27. Synaptobrevin N-terminally bound to syntaxin-SNAP-25 defines the primed vesicle state in regulated exocytosis.
    J Cell Biol. 2010 Feb 8;188(3):401-13 PMID: 20142423
  28. Two distinct secretory vesicle-priming steps in adrenal chromaffin cells.
    J Cell Biol. 2010 Sep 20;190(6):1067-77 PMID: 20855507
  29. Structural basis for a Munc13-1 homodimer to Munc13-1/RIM heterodimer switch.
    PLoS Biol. 2006 Jul;4(7):e192 PMID: 16732694
  30. Munc18-1 binds directly to the neuronal SNARE complex.
    Proc Natl Acad Sci U S A. 2007 Feb 20;104(8):2697-702 PMID: 17301226
  31. Munc13-1 is a presynaptic phorbol ester receptor that enhances neurotransmitter release.
    Neuron. 1998 Jul;21(1):123-36 PMID: 9697857
  32. Total arrest of spontaneous and evoked synaptic transmission but normal synaptogenesis in the absence of Munc13-mediated vesicle priming.
    Proc Natl Acad Sci U S A. 2002 Jun 25;99(13):9037-42 PMID: 12070347
  33. Binding of Munc18-1 to synaptobrevin and to the SNARE four-helix bundle.
    Biochemistry. 2010 Mar 2;49(8):1568-76 PMID: 20102228
  34. Open syntaxin docks synaptic vesicles.
    PLoS Biol. 2007 Aug;5(8):e198 PMID: 17645391
  35. A protein assembly-disassembly pathway in vitro that may correspond to sequential steps of synaptic vesicle docking, activation, and fusion.
    Cell. 1993 Nov 5;75(3):409-18 PMID: 8221884
  36. A structure-based mechanism for vesicle capture by the multisubunit tethering complex Dsl1.
    Cell. 2009 Dec 11;139(6):1119-29 PMID: 20005805
  37. Sec1p binds to SNARE complexes and concentrates at sites of secretion.
    J Cell Biol. 1999 Jul 26;146(2):333-44 PMID: 10427089
  38. The structure of the exocyst subunit Sec6p defines a conserved architecture with diverse roles.
    Nat Struct Mol Biol. 2006 Jun;13(6):555-6 PMID: 16699513
  39. Three-dimensional structure of an evolutionarily conserved N-terminal domain of syntaxin 1A.
    Cell. 1998 Sep 18;94(6):841-9 PMID: 9753330
  40. Munc13 mediates the transition from the closed syntaxin-Munc18 complex to the SNARE complex.
    Nat Struct Mol Biol. 2011 May;18(5):542-9 PMID: 21499244
  41. Regulation of transmitter release by Unc-13 and its homologues.
    Curr Opin Neurobiol. 2000 Jun;10(3):303-11 PMID: 10851170
  42. Functional interaction of the active zone proteins Munc13-1 and RIM1 in synaptic vesicle priming.
    Neuron. 2001 Apr;30(1):183-96 PMID: 11343654
  43. The N-terminal peptide of the syntaxin Tlg2p modulates binding of its closed conformation to Vps45p.
    Proc Natl Acad Sci U S A. 2009 Aug 25;106(34):14303-8 PMID: 19667197
  44. Membrane fusion: grappling with SNARE and SM proteins.
    Science. 2009 Jan 23;323(5913):474-7 PMID: 19164740
  45. C2-domains, structure and function of a universal Ca2+-binding domain.
    J Biol Chem. 1998 Jun 26;273(26):15879-82 PMID: 9632630
  46. HKL-3000: the integration of data reduction and structure solution--from diffraction images to an initial model in minutes.
    Acta Crystallogr D Biol Crystallogr. 2006 Aug;62(Pt 8):859-66 PMID: 16855301
  47. Coot: model-building tools for molecular graphics.
    Acta Crystallogr D Biol Crystallogr. 2004 Dec;60(Pt 12 Pt 1):2126-32 PMID: 15572765
  48. Crystal structure of a SNARE complex involved in synaptic exocytosis at 2.4 A resolution.
    Nature. 1998 Sep 24;395(6700):347-53 PMID: 9759724
  49. Facile detection of protein-protein interactions by one-dimensional NMR spectroscopy.
    Biochemistry. 2003 Mar 18;42(10):2774-80 PMID: 12627942
  50. PHENIX: building new software for automated crystallographic structure determination.
    Acta Crystallogr D Biol Crystallogr. 2002 Nov;58(Pt 11):1948-54 PMID: 12393927
  51. Mammalian homologues of Caenorhabditis elegans unc-13 gene define novel family of C2-domain proteins.
    J Biol Chem. 1995 Oct 20;270(42):25273-80 PMID: 7559667
  52. UNC-13 interaction with syntaxin is required for synaptic transmission.
    Curr Biol. 2005 Dec 20;15(24):2236-42 PMID: 16271476
  53. A common molecular basis for membrane docking and functional priming of synaptic vesicles.
    Eur J Neurosci. 2009 Jul;30(1):49-56 PMID: 19558619
  54. Munc18-1 in secretion: lonely Munc joins SNARE team and takes control.
    Trends Neurosci. 2007 Nov;30(11):564-72 PMID: 17956762
  55. An open form of syntaxin bypasses the requirement for UNC-13 in vesicle priming.
    Nature. 2001 Jul 19;412(6844):338-41 PMID: 11460165
  56. Convergence and divergence in the mechanism of SNARE binding by Sec1/Munc18-like proteins.
    Proc Natl Acad Sci U S A. 2003 Jan 7;100(1):32-7 PMID: 12506202
  57. Unraveling the mechanisms of synaptotagmin and SNARE function in neurotransmitter release.
    Trends Cell Biol. 2006 Jul;16(7):339-50 PMID: 16698267
  58. Munc13-1 is essential for fusion competence of glutamatergic synaptic vesicles.
    Nature. 1999 Jul 29;400(6743):457-61 PMID: 10440375
  59. A protein interaction node at the neurotransmitter release site: domains of Aczonin/Piccolo, Bassoon, CAST, and rim converge on the N-terminal domain of Munc13-1.
    J Neurosci. 2009 Oct 7;29(40):12584-96 PMID: 19812333
  60. Drosophila UNC-13 is essential for synaptic transmission.
    Nat Neurosci. 1999 Nov;2(11):965-71 PMID: 10526334
  61. Structural characterization of Tip20p and Dsl1p, subunits of the Dsl1p vesicle tethering complex.
    Nat Struct Mol Biol. 2009 Feb;16(2):114-23 PMID: 19151722
  62. Phaser crystallographic software.
    J Appl Crystallogr. 2007 Aug 1;40(Pt 4):658-674 PMID: 19461840
  63. Remote homology between Munc13 MUN domain and vesicle tethering complexes.
    J Mol Biol. 2009 Aug 21;391(3):509-17 PMID: 19563813
  64. Structure and conformational changes in NSF and its membrane receptor complexes visualized by quick-freeze/deep-etch electron microscopy.
    Cell. 1997 Aug 8;90(3):523-35 PMID: 9267032
  65. Conformational switch of syntaxin-1 controls synaptic vesicle fusion.
    Science. 2008 Sep 12;321(5895):1507-10 PMID: 18703708
  66. Vam3p structure reveals conserved and divergent properties of syntaxins.
    Nat Struct Biol. 2001 Mar;8(3):258-64 PMID: 11224573
  67. UNC-13 is required for synaptic vesicle fusion in C. elegans.
    Nat Neurosci. 1999 Nov;2(11):959-64 PMID: 10526333
  68. The synaptic SNARE complex is a parallel four-stranded helical bundle.
    Nat Struct Biol. 1998 Sep;5(9):765-9 PMID: 9731768
  69. Sec15 interacts with Rab11 via a novel domain and affects Rab11 localization in vivo.
    Nat Struct Mol Biol. 2005 Oct;12(10):879-85 PMID: 16155582
  70. At the junction of SNARE and SM protein function.
    Curr Opin Cell Biol. 2010 Aug;22(4):488-95 PMID: 20471239
  71. Munc13 C2B domain is an activity-dependent Ca2+ regulator of synaptic exocytosis.
    Nat Struct Mol Biol. 2010 Mar;17(3):280-8 PMID: 20154707
  72. Munc13-1 C1 domain activation lowers the energy barrier for synaptic vesicle fusion.
    J Neurosci. 2007 Jan 31;27(5):1200-10 PMID: 17267576
  73. A minimal domain responsible for Munc13 activity.
    Nat Struct Mol Biol. 2005 Nov;12(11):1017-8 PMID: 16228007
Article Info
Journal
Structure (London, England : 1993)
Abbr.
Structure
ISSN
1878-4186
DOI
10.1016/j.str.2011.07.012
Published
2011-10-12
Pages
1443-55
Language
English
Region
United States
NLM ID
101087697
PMCID
PMC3197213
Subset
IM
Grants
NINDS NIH HHS · R01 NS037200 · United States
NINDS NIH HHS · R01 NS037200-14 · United States
NINDS NIH HHS · NS37200 · United States
Corrections
CommentIn
PMID: 22000505
External Links
PubMed source DOI: 10.1016/j.str.2011.07.012 PMC Full Text View journal details
Analysis Services
Analysis Services

Contact

No. 2 Wenbo Road, Zhangqiu District, Jinan, Shandong

Qilu Normal University · Genelibs Bioinformatics Lab

750 Shunhua Rd, Jinan

2F, Bldg F, University Science Park

Tel: 0531-88819269

WeChat Official Account

Follow our WeChat subscription account for real-time updates and the latest in medical and biological research.


Business Email

E-mail: [email protected]

Copyright © 2026.Genelibs Jinan Honghui Biotechnology Co., Ltd. 鲁ICP备20007159号-2